United States

Department of

Agriculture

Animal and

Plant Health

Inspection

Service

Veterinary

Services

National

Animal Health

Monitoring

System

March 2007

Equine 2005

Part II: Changes in the U.S. Equine Industry,

1998-2005
Mention of companies or commercial products does

not imply recommendation or endorsement by the

USDA over others not mentioned. USDA neither

guarantees nor warrants the standard of any product

mentioned. Product names are mentioned solely to

report factually on available data and to provide

specific information.

USDA:APHIS:VS:CEAH

NRRC Building B, M.S. 2E7

2150 Centre Avenue

Fort Collins, CO 80526-8117

970.494.7000

E-mail: NAHMS@aphis.usda.gov

http://nahms.aphis.usda.gov

#N452.0307

The U.S. Department of Agriculture (USDA) prohibits

discrimination in all its programs and activities on the

basis of race, color, national origin, age, disability, and

where applicable, sex, marital status, familial status,

parental status, religion, sexual orientation, genetic

information, political beliefs, reprisal, or because all or

part of an individual’s income is derived from any public

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all programs.) Persons with disabilities who require

alternative means for communication of program

information (Braille, large print, audiotape, etc.) should

contact USDA’s TARGET Center at (202) 720–2600

(voice and TDD). To file a complaint of discrimination,

write to USDA, Director, Office of Civil Rights, 1400

Independence Avenue, S.W., Washington, D.C.

20250–9410, or call (800) 795–3272 (voice) or (202)

720–6382 (TDD). USDA is an equal opportunity

provider and employer.

Cover photo courtesy of

Judy Rodriguez
USDA APHIS VS / i

Acknowledgments

This report was a cooperative effort between two U.S. Department of Agriculture

(USDA) agencies: the National Agricultural Statistics Service (NASS) and the

Animal and Plant Health Inspection Service (APHIS).

We would like to thank the NASS enumerators who visited equine operations

and collected data for both the Equine ‘98 and Equine 2005 studies. Their hard

work and dedication were invaluable. Thanks also to the veterinary medical

officers who collected data for Equine ‘98. In addition, a note of appreciation

goes to the personnel at the USDA-APHIS-Veterinary Services’ Centers for

Epidemiology and Animal Health for their efforts in generating and distributing

this report, to Dr. Josie Traub-Dargatz for her guidance in study development and

implementation, and to our reviewers for providing valuable expertise and

guidance through their comments.

All participants are to be commended, particularly the equine owners whose

voluntary efforts made this report possible.

Dr. Larry Granger

Director

Centers for Epidemiology and Animal Health
ii / Equine 2005

Suggested bibliographic citation for this report:

USDA. 2006. Equine 2005, Part II: Changes in the U.S.

Equine Industry,1998-2005

USDA-APHIS-VS, CEAH. Fort Collins, CO #N452-0307

Contacts for further information:

Questions or comments on Equine 2005 study methods or requests for

additional data analysis: Ms. Anne Berry (970) 494-7000

Information on reprints or other reports: Ms. Anne Berry (970) 494-7000

E-mail NAHMS@aphis.usda.gov
USDA APHIS VS / iii

Table of Contents

Introduction 1

Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002 2

A. Historical Changes in the U.S. Equine Industry 2

1. Inventory on farms and number of farms—Census of Agriculture 2

2. Number of equids on farms and number of farms—Census of

Agriculture, 1997–2002 4

3. State-level inventory on farms and number of farms—Census of

Agriculture, 1997–2002 5

4. Changes in U.S. equine inventory on all places (farms and nonfarms),

1997–2002 7

5. Value of U.S. livestock live animal exports, 1996–2005 9

Section II: Specific Disease Surveillance in the U.S. Equine Industry 10

A. Equine Infectious Anemia (EIA) 10

1. Number of EIA tests, 1972–2005 10

2. Percentage of positive EIA tests 11

3. Number of EIA tests and percentage positive by State, 1999–2005 11

B. West Nile Virus (WNV) 13

1. Background 13

2. Chronological spread of equine WNV across the United States 14

C. Vesicular Stomatitis (VS) 16

1. Background 16

2. Summary statistics, 1995–2005 16

Section III: Management and Health Changes in the U.S. Equine Industry,

1998-2005 18

1. Background 18

2. Terms 20

A. General 22

1. Primary function of operations 22

2. Primary use of equids 24

3. Equid distribution 25

4. Type of equid 26

5. Age of resident equids 29

6. Identification method 30

B. Health and Health Management 33

1. Primary method of recording equine information 33

2. Testing 34

3. Familiarity with EIA 35

4. EIA testing 36

5. Vaccinations 38

6. Foal health 42

7. Equid health 46

8. Births 50
iv / Equine 2005

9. Foal deaths 51

10. Equid deaths 53

C. Biosecurity 55

1. Nonresident equids 55

2. Additions 57

3. Contact with other animals 60

D. Equid Movement 61

1. Distance traveled 61

2. Vehicle transportation 62

3. Destination 63

4. Direct contact with outside equids during trips 63

E. General Management 65

1. Feed source 65

2. Drinking water 66

3. Insect control 66

4. Manure management 68

Appendix: Study Objectives and Related Outputs 69
Introduction

USDA APHIS VS / 1

Introduction

In 1983, promoters of the concept that would become the USDA’s National

Animal Health Monitoring System (NAHMS) envisioned a program that would

monitor changes and trends in national animal health and management, thereby

providing periodic snapshots of the U.S. livestock industries. With these industry

overviews, stakeholders could identify opportunities for improvement, provide

changing priorities for research and special studies, and detect emerging

problems. Two NAHMS snapshots of the U.S. equine industry have been

performed via the Equine 1998 and Equine 2005 studies.

Section I of this report presents demographic changes of the U.S. equine

population from a historical perspective using data provided by the National

Agricultural Statistics Service (NASS), Census of Agriculture, and U.S. Bureau of

Census. Section II includes historical data regarding equine infectious anemia,

West Nile virus, and vesicular stomatitis. Results of the two NAHMS studies in

Section III provide an overview of changes in U.S. equine management and

health from 1998 through 2005. Results of the Equine 1998 and 2005 studies

and other NAHMS studies are available online at:

<http://nahms.aphis.usda.gov>.

For questions about this report or additional copies contact:

USDA-APHIS-VS-CEAH

2150 Centre Avenue, Bldg. B, MS 2E7

Fort Collins, CO 80526-8117

970.494.7000
Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

2 / Equine 2005

Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

A. Historical

Changes in the U.S.

Equine Industry

This section presents data from sources other than the NAHMS Equine ’98 and 2005 studies, so as to provide

comprehensive information on the U.S. equine population.

1. Inventory on farms and number of farms—Census of Agriculture

The Census of Agriculture has collected and reported equine inventory numbers

roughly at 5-year intervals since 1840. The table on p. 3 shows inventory

numbers from 1850-1920 at 10-year intervals and at 5-year intervals thereafter.

The Census of Agriculture aggregates and reports data from all places that

qualify as a farm. The current definition of a farm, first used in 1974, is a place

that could or did actually sell $1,000 of agricultural products annually. In addition,

as of 1987 any operation that has five or more equids (other than commercial

enterprises such as race tracks) qualifies as a farm, even if it has no other

agricultural activity.

The total number of equids on farms can be derived from Census reports by

combining the reported inventories for horses and ponies with the inventories for

mules, donkeys, and burros (some years donkeys and burros were excluded and

only mule numbers were collected). In 1954 and 1959 inventories were

combined and reported under the “Horses and Ponies” category. The total

number of farms with any equids cannot be similarly derived, as a given farm

could have had more than one type of equid. Therefore, the table on p. 3 does

not provide number of farms with equids.

Total equids increased rapidly from 4.9 million head in 1850 to a peak of 25.2

million head in 1920. Inventories thereafter mostly declined, except for the 20

years prior to the last Census. There were 3.7 million equids on farms in the

United States in 2002, about three-fourths of the 4.9 million reported in 1850.

Horse and pony numbers peaked in 1910 at 19.8 million head. It is likely that the

number of horses and ponies in the United States declined rapidly during the

1920s and 1930s because motorized vehicles replaced them as a means of

transportation. By 1950, the number of horses and ponies was only about onethird of what it was in 1925. The decline continued until the low of 1.6 million

head in 1974. As of 2002, there were 3.6 million horses and ponies in the United

States, the highest number on farms since 1954.

There have always been fewer mules, donkeys, and burros than horses and

ponies in the United States. The number of mules peaked in 1925 at 5.7 million

head, about one-third the number of horses and ponies. The number of mules,

donkeys, and burros declined rapidly in the late 1950s, 1960s and 1970s to

27,430 head in 1982. In 2002, there were 105,358 mules, donkeys, and burros.

Interestingly, in 2002 the number of horses and ponies per farm (6.7 head), and

the number of mules, donkeys, and burros (3.5 head) were at all-time highs.
USDA APHIS VS / 3

Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

Changes in U.S. equine inventory, 1850–2002:

Horses and Ponies Mules, Burros, and Donkeys 

Year/Month 

Total 

Inventory 

Number 

of Farms 

Avg. 

per 

Farm 

Total 

Inventory 

Number 

of Farms 

Avg. 

per 

Farm 

Total 

Equine 

Inventory 

Pct. 

of 

1850 

1850 (June 1) 4,336,719 N/A N/A 559,331 N/A N/A 4,896,050 100.0 

1860 (June 1) 6,249,174 N/A N/A 1,151,148 N/A N/A 7,400,322 151.1 

1870 (June 1) 7,145,370 N/A N/A 1,125,415 N/A N/A 8,270,785 168.9 

1880 (June 1) 10,357,488 N/A N/A 1,812,808 N/A N/A 12,170,296 248.6 

1890 (June 1) 15,266,244 N/A N/A 2,251,8762 N/A N/A 17,518,120 357.8 

1900 (June 1) 18,267,020 4,530,628 4.0 3,264,6152 1,480,6522 2.2 21,531,6352 439.8 

1910 (Apr. 15) 19,833,113 4,692,814 4.2 4,209,7692 1,869,0052 2.3 24,042,8822 491.1 

1920 (Jan. 1) 19,767,161 4,704,235 4.2 5,432,3912 2,259,7462 2.4 25,199,5522 514.7 

1925 (Jan. 1) 16,400,623 5,365,513 3.1 5,680,8972 N/A N/A 22,081,5202 451.0 

1930 (Apr. 1) 13,510,839 5,024,713 2.7 5,375,0172 N/A N/A 18,885,8562 385.7 

1935 (Jan. 1) 11,857,850 3,536,597 3.4 4,818,1602 2,255,8452 2.1 16,676,0102 340.6 

1940 (Apr. 1) 10,086,971 3,148,656 3.2 3,844,5602 1,845,5172 2.1 13,931,5312 284.5 

1945 (Jan. 1) 8,499,204 2,828,412 3.0 3,129,5902 1,486,2092 2.1 11,628,7942 237.5 

1950 (Apr. 1) 5,401,646 2,120,843 2.5 2,202,2642 1,101,7992 2.0 7,603,9102 155.3 

1954 (Oct.-Nov) 4,141,2881 1,799,8991 2.3 N/A N/A N/A 4,141,2881 84.6 

1959 (Oct.-Nov.) 2,955,2561 1,138,9861 2.6 N/A N/A N/A 2,955,2561 60.4 

1964 (Nov.-Dec.) N/A N/A N/A N/A N/A N/A N/A N/A 

1969 (Dec. 31) 2,237,981 547,246 4.1 66,128 34,309 1.9 2,304,109 47.1 

1974 (Dec. 31) 1,595,640 359,051 4.4 N/A N/A N/A N/A N/A 

1978 (Dec. 31) 1,957,028 399,335 4.9 56,703 27,631 2.1 2,013,731 41.1 

1982 (Dec. 31) 2,260,791 417,042 5.4 27,430 10,431 2.6 2,288,221 46.7 

1987 (Dec. 31) 2,456,951 415,565 5.9 56,520 23,311 2.4 2,513,471 51.3 

1992 (Dec. 31) 2,049,522 338,346 6.1 67,692 25,589 2.6 2,117,214 43.2 

1997* (Dec. 31) 3,020,117 490,517 6.2 123,211 44,096 2.8 3,143,328 64.2 

2002* (Dec. 31) 3,644,278 542,223 6.7 105,358 29,936 3.5 3,749,636 76.6 

Notes: 

1890-1954: Number of mules on farms. Donkeys and burros were excluded. 

1940: Horse and pony inventory includes only animals older than 3 months of age. 

1954 and 1959: Horse, pony, and mule inventories reported together. 

1964: No equine data. 

N/A = not available. 

*1997 and 2002 = Census of Agriculture adjusted for incompleteness. 

Source: USDA-NASS Census of Agriculture 1997 and 2002; 1850-1992 prepared by Commerce Department U.S. Bureau 

of Census. 

1

Farms reporting horses and/or mules in some States. 

2

Excludes burros and donkeys. 
Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

4 / Equine 2005

2. Number of equids on farms and number of farms—Census of

Agriculture, 1997–2002

The 2002 Census reported 3.7 million equids on farms in the United States, a

19.3 percent increase from the number reported in the 1997 Census. A total of

552,900 farms had equids in 2002, a 10.2 percent increase from 1997.

Interestingly, the roughly half-million farms with equids is nearly three-fourths the

number of farms with beef cows, six times the number of farms with milk cows,

and seven times the number of hog and sheep farms.

The table below provides comparisons between 1997 and 2002 for various levels

of farm size (number of equids on the farm). For example, for the smallest

farms—those with 1 to 4 equids—the number of equids for both Census periods

was about 657,000 head, while the number of the smallest farms actually

declined 3.8 percent from 285,000 farms in 1997 to 274,300 farms in 2002. Note

that this particular category is composed of places that sold at least $1,000 worth

of agricultural products and also had one to four equids. For the remaining size

categories, the operation may have qualified as a farm based upon the number

of equids (five or more) and/or sales of $1,000 or more. For farms with 5 to 9

equids, the total number of equids increased 27.6 percent between 1997 and

2002, while the number of equids on farms with 10 to 19 equids increased 40.3

percent. The number of equids on farms with 20 or more equids increased 7.8

percent between 1997 and 2000, while the number of farms increased 10.5

percent, indicating that the number of equids per farm decreased.

Changes in U.S. equine inventory and number of farms, by size of farm, 1997–

2002:

 Equids Farms 

Number 

of 

Equids 

1997 

Number 

(x1,000)

2002 

Number 

(x1,000)

2002 as 

% of 

1997 

1997 

Number 

(x1,000)

2002 

Number 

(x1,000)

2002 as 

% of 

1997 

1 to 4 656.9 656.6 100.0 285.0 274.3 96.2 

5 to 9 867.8 1,107.1 127.6 136.0 172.4 126.8 

10 to 19 740.3 1,038.8 140.3 58.0 81.0 139.7 

20 or 

more 

878.3 947.1 107.8 22.8 25.2 110.5 

All 3,143.3 3,749.6 119.3 501.8 552.9 110.2 

5 or 

more 2,486.4 3,093.0 124.4 216.7* 278.6 128.6 

*Sum may not add due to rounding. 

Source: USDA-NASS Census of Agriculture 
USDA APHIS VS / 5

Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

3. State-level inventory on farms and number of farms—Census of

Agriculture, 1997–2002

A comparison by State of the data from the two Census periods is presented in

the table on p. 6. Note that in 2002 Texas had 10.2 percent of the horses and

ponies in the United States, with 372,300 head reported on 62,800 farms. The

next States with the most horses and ponies (nearly 150,000 head) were

Kentucky, Oklahoma, and Tennessee. Texas had 21.5 percent of the U.S. mules,

burros, and donkeys. Note also that this table identifies the 28 States for which

in-depth health and management practice trends are discussed in Section III of

this report.

Photograph by Judy Rodriguez
Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

6 / Equine 2005

Changes in equine inventories and number of farms with equids, by State, 1997

and 2002:

 Inventory—Animals on Farms (x1,000) Number of Farms with Equids (x1,000)

Horses and 

Ponies 

Mules, Burros, 

and Donkeys All Equids1 Horses and 

Ponies 

Mules, Burros, 

and Donkeys All Equids 

State 1997 2002 1997 2002 1997 2002 1997 2002 1997 2002 1997 2002 

Alabama* 53.9 65.5 3.7 3.6 57.6 69.1 9.7 10.3 1.3 1.0 10.1 10.8 

Alaska 2.4 1.9 0.0 0.0 2.4 1.9 0.2 0.2 0.0 0.0 0.2 0.2 

Arizona 47.7 46.9 1.3 0.5 49.0 47.4 4.3 3.7 0.5 0.2 4.3 3.8 

Arkansas 46.5 72.3 3.0 2.9 49.5 75.2 9.6 12.0 1.1 0.8 9.8 12.3 

California* 149.3 132.0 4.0 2.5 153.3 134.4 19.3 16.4 1.5 0.7 19.5 16.6 

Colorado* 89.1 107.1 2.8 1.9 91.9 109.0 12.4 13.9 1.0 0.6 12.5 14.0 

Connecticut 9.9 9.5 0.2 0.1 10.1 9.6 1.2 1.2 0.1 0.1 1.3 1.2 

Delaware 3.7 3.5 0.0 0.0 3.7 3.5 0.5 0.5 0.0 0.0 0.5 0.5 

Florida* 70.1 99.9 2.7 1.6 72.8 101.5 9.8 12.8 0.7 0.6 10.0 12.9 

Georgia* 49.3 74.0 2.4 2.7 51.6 76.8 8.5 11.5 0.9 0.8 8.8 11.8 

Hawaii 4.9 4.6 0.1 0.1 5.0 4.6 0.6 0.5 0.0 0.0 0.6 0.5 

Idaho 69.5 83.2 2.3 1.2 71.9 84.4 10.5 11.6 0.8 0.4 10.6 11.6 

Illinois* 63.1 59.6 2.2 1.7 65.3 61.3 9.8 9.0 0.8 0.5 10.0 9.2 

Indiana* 76.8 98.4 2.6 2.1 79.4 100.5 12.5 14.5 0.8 0.6 12.8 14.7 

Iowa 68.6 77.1 2.5 2.1 71.1 79.2 11.2 11.5 0.8 0.4 11.4 11.6 

Kansas* 58.1 67.4 2.0 1.5 60.0 68.9 11.9 12.2 0.8 0.5 12.1 12.3 

Kentucky* 108.6 149.5 4.6 4.1 113.3 153.6 15.9 20.1 1.7 1.2 16.5 20.5 

Louisiana* 41.3 47.8 1.8 1.1 43.1 48.9 7.6 7.1 0.6 0.3 7.8 7.3 

Maine 8.8 12.7 0.2 0.2 9.0 12.9 1.6 2.2 0.1 0.1 1.6 2.2 

Maryland* 25.7 25.9 0.7 0.4 26.4 26.4 3.1 3.2 0.3 0.2 3.1 3.2 

Massachusetts 13.8 15.5 0.5 0.2 14.3 15.7 1.9 1.9 0.1 0.1 2.0 1.9 

Michigan* 82.7 104.9 1.7 1.7 84.4 106.6 11.9 15.0 0.6 0.5 12.0 15.1 

Minnesota* 69.7 92.8 1.5 1.3 71.2 94.0 11.5 14.3 0.6 0.4 11.6 14.4 

Mississippi 46.9 66.8 2.6 2.1 49.5 68.9 9.0 10.8 1.0 0.7 9.3 11.0 

Missouri* 104.1 141.4 5.3 4.7 109.4 146.0 19.7 23.6 1.9 1.4 20.2 24.1 

Montana* 80.9 94.4 2.8 3.2 83.8 97.6 12.0 12.5 0.9 0.7 12.1 12.6 

Nebraska 50.1 58.9 1.2 1.4 51.3 60.3 9.1 9.3 0.4 0.3 9.2 9.4 

Nevada 15.7 16.1 0.4 0.2 16.0 16.3 1.8 1.7 0.1 0.1 1.8 1.8 

New Hampshire 7.5 7.9 0.2 0.2 7.7 8.2 1.2 1.2 0.1 0.1 1.2 1.3 

New Jersey* 25.0 26.9 0.4 0.5 25.5 27.4 2.7 3.0 0.2 0.2 2.7 3.1 

New Mexico* 47.8 46.7 1.4 0.8 49.2 47.5 7.8 7.2 0.6 0.2 7.9 7.3 

New York* 67.3 75.3 1.3 1.4 68.6 76.7 9.6 10.9 0.6 0.5 9.8 11.0 

North Carolina 57.8 64.2 2.1 2.2 59.9 66.4 10.4 10.9 0.9 0.7 10.7 11.1 

North Dakota 38.3 43.4 0.5 0.2 38.8 43.6 5.4 5.0 0.2 0.1 5.4 5.0 

Ohio* 101.6 134.4 3.4 3.7 105.0 138.1 16.3 19.9 1.2 1.0 16.6 20.3 

Oklahoma* 111.8 150.1 4.4 4.3 116.3 154.4 22.6 25.7 1.9 1.4 23.1 26.2 

Oregon* 82.6 92.4 3.8 2.8 86.5 95.2 13.6 14.5 1.2 0.8 13.8 14.7 

Pennsylvania* 99.5 113.4 6.5 3.7 105.9 117.1 16.1 16.8 1.6 0.8 16.3 17.1 

Rhode Island 1.9 2.0 0.0 0.0 1.9 2.0 0.3 0.2 0.0 0.0 0.3 0.2 

South Carolina 32.5 40.7 1.1 1.2 33.6 41.9 5.6 6.3 0.5 0.3 5.7 6.4 

South Dakota 55.1 69.6 0.8 0.8 55.8 70.3 7.4 7.9 0.4 0.2 7.4 8.0 

Tennessee* 114.7 148.7 8.2 6.4 122.9 155.0 20.3 24.0 2.9 1.9 21.3 24.9 

Texas* 296.9 372.3 22.2 22.7 319.1 395.1 57.2 62.8 8.1 6.2 60.0 65.7 

Utah 54.5 61.4 1.0 0.6 55.5 61.9 8.1 8.5 0.4 0.2 8.1 8.5 

Vermont 11.9 11.2 0.3 0.4 12.2 11.7 1.7 1.8 0.1 0.1 1.8 1.9 

Virginia* 68.3 81.3 2.9 2.5 71.2 83.9 11.0 12.3 1.0 0.7 11.3 12.6 

Washington* 85.8 76.0 2.8 1.5 88.6 77.5 12.9 11.2 1.0 0.5 13.0 11.3 

West Virginia 22.5 31.9 1.2 1.1 23.8 32.9 5.0 6.2 0.5 0.4 5.2 6.4 

Wisconsin* 74.0 102.0 2.4 2.1 76.4 104.1 13.1 16.3 0.9 0.6 13.3 16.5 

Wyoming* 51.4 62.9 1.1 0.8 52.5 63.7 5.4 6.1 0.4 0.2 5.5 6.1 

 

Total1 (28 States*) 2,349.4 2,843.0 101.6 87.3 2,451.2 2,930.3 384.2 427.1 36.0 25.0 393.7 436.3 

Total2 (50 States) 3,020.1 3,644.3 123.2 105.4 3,143.3 3,749.6 490.5 542.2 44.1 29.9 501.8 552.9 1

Sum of horses and ponies, and mules, burros, and donkeys may not equal sum of all equids because of rounding. 

2

Sum may not equal total because of rounding. 

*States participating in NAHMS Equine 1998 and 2005 studies. 

Source: USDA-NASS Census of Agriculture. Values of 0.0 = fewer than 50 reported.
USDA APHIS VS / 7

Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

4. Changes in U.S. equine inventory on all places (farms and nonfarms),

1997–2002

There is no accurate estimate of the current total number of equids in the United

States because the number of equids on nonfarm operations does not exist. Onfarm equine estimates are conducted every 5 years as part of the Census of

Agriculture (for the definition of a “farm” see p. 2). The only nonfarm equine

estimates conducted by NASS occurred in 1998-99. USDA does not have an

equine estimation program like it does for other livestock, poultry, and

aquaculture. Speculation would suggest that now each Census of Agriculture

represents a smaller and smaller portion of the equine population—currently 50

to 60 percent of the total equine population—because it only counts equids on

places that meet the definition of a farm.

Today, statistics exist on nearly every phase of the economy. For example, in

animal agriculture we know how many goats there are—even the numbers of

mink and honeybee colonies are collected. During the early years of the Census,

farm and ranch work was definitely the primary use of equids. In addition, a high

percentage of the human population resided on farms and ranches and used

equids as their primary means of transportation. The development of the

automobile reduced the need for equids in the large farm sector as well as the

urban sector. Horse-drawn farm machinery was soon altered, as the tractor was

developed and fewer equids were needed on the farm.

One might speculate that the Census of Agriculture reports showing a large

increase of equids in the early 1900s and the subsequent drop to the low levels

in the 1950s still represented a high percentage of all equids in the United States.

During the last few decades, small communities and the outskirts of cities have

become popular destinations for people looking for a few acres in a “rural”

environment. These rural environments provide room for a horse, or several

horses, for riding and pleasure. The only measure we have in the United States

quantifying this phenomena is the baseline study conducted by NASS in 1998

and 1999 (see table p. 8). This study showed that 3.20 million equids were on

farms and 2.05 million were on nonfarms. Therefore, the conclusion is that the

1997 Census of Agriculture represents about 61 percent of the equids in the

United States. No estimates were provided from the study on the number of

places with equids.
Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

8 / Equine 2005

U.S. equine inventory, 1997–2002:

The American Horse Council Foundation published an estimate of U.S. horse

inventory for calendar year 2003. The estimate resulted from a survey of horse

owners and suppliers conducted by Deloitte Consulting, LLC, a large auditing

firm. The Deloitte estimate of 9.2 million horses in 2003 was nearly twice as

great as the USDA-NASS equine estimate for 1999 (5.3 million equids), the last

year for which NASS published such an inventory count. The large difference

between the USDA-NASS 1999 estimate and Deloitte’s 2003 estimate raises

questions as to the true number of horses in the United States. USDA-NASS

conducted a review of Deloitte’s methodology at the request of USDA-APHIS.

Based on this review, several distinct differences were identified between the two

approaches to measuring the U.S. inventory.

First, different list-development procedures were employed by Deloitte and

NASS, which leads to different adjustment procedures for missing data. Second,

NASS methodology employs a multiframe approach, supplementing list-building

activities with an area frame sample. The area frame is land-based and

inherently includes all possible equine operations. It provides the capability to

measure and adjust for list under-coverage and provides a measure of

associated sampling error. Third, differences in list construction, nonresponse

follow-up procedures, data adjustment procedures, and survey focus all

contribute to the wide disparity in final inventory estimated by both studies.

 Inventory (Million Head) 

Date Farm Nonfarm Total 

No. Farms 

(x1,000)

1997 Census 3.14 N/A N/A 501.8 

Jan. 1, 1998 3.20 2.05 5.25 N/A 

(percent of 

total) (61.0) (39.0) (100.0) 

Jan. 1, 1999 N/A N/A 5.32 N/A 

2002 Census 3.75 N/A N/A 552.9 
USDA APHIS VS / 9

Section I: Demographic Changes in the U.S. Equine Industry, 1850–2002

5. Value of U.S. livestock live animal exports, 1996–2005

Although the value of U.S. livestock exports fluctuates greatly, the value of U.S.

equine exports exceeded the value of U.S. swine, cattle, poultry, and sheep liveanimal exports each year from 1996 through 2005. In addition to the exports

recorded here, there are also seasonal, temporary export and return of U.S.

equids to other countries.

Changes in U.S. livestock export values, 1996–2005:

Cumulative-to-Date U.S. Export Values (x$1,000)—World Totals, Live 

Animals 

Year Equids Swine Cattle Poultry Sheep 

1996 248,445 8,816 113,141 95,071 14,204 

1997 270,926 11,651 177,262 102,026 59,135 

1998 316,537 23,414 162,363 98,673 25,274 

1999 293,089 18,803 174,008 96,512 18,964 

2000 422,648 11,901 271,607 84,454 17,750 

2001 447,626 11,560 270,134 91,495 18,682 

2002 302,039 37,967 131,433 94,417 19,930 

2003 329,671 33,086 63,223 90,852 10,273 

2004 343,872 32,804 3,230 63,900 6,449 

2005 461,541 25,936 7,216 95,522 6,507 

Source: USDA, Foreign Agricultural Service 
Section II: Specific Disease Surveillance in the U.S. Equine Industry

10 / Equine 2005

Section II: Specific Disease Surveillance in the U.S. Equine Industry

This section presents data from sources other than the NAHMS Equine ’98 and 2005 studies, so as to provide

comprehensive information on three equine diseases: equine infectious anemia, West Nile virus, and vesicular

stomatitis.

A. Equine Infectious

Anemia (EIA)

1. Number of EIA tests, 1972–2005

EIA testing in the United States utilizing the Coggins test began in 1972. Since

then, other tests for detecting EIA have been developed and approved. Data exist

from 1972 to 2005 on the number of tests performed by each State annually and

the percentage of those tests that were positive for EIA. The number of EIA tests

has generally increased, with over 2 million tests performed in 2005. This increase

could be due to multiple factors, e.g., more awareness of the disease, changes in

testing requirements, more animal movement requiring testing, or an increase in

the equine population. An interactive map of EIA in the United States is available at

<http://www.aphis.usda.gov/vs/nahps/equine/eia/web-mapping.html>.

0

500,000

1,000,000

1,500,000

2,000,000

2,500,000

1975 1980 1985 1990 1995 2000 2005

Year

Number

of tests

Number of EIA Tests Performed in the United States, 1972-2005

*Data not available for 1981 and 1982

*
USDA APHIS VS / 11

 Section II: Specific Disease Surveillance in the U.S. Equine Industry

2. Percentage of positive EIA tests

The percentage of positive EIA tests among those tested declined steadily from

nearly 4 percent in 1972 to less than 0.1 percent in 2005, with the most dramatic

decline occurring from 1972 to 1978.

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

1975 1980 1985 1990 1995 2000 2005

Year

Percent tests

positive

Percentage of Samples that Tested Positive for EIA in the United

States, 1972-2005

*Data not available for 1981 and 1982

*

3. Number of EIA tests and percentage positive by State, 1999–2005

The number of EIA tests increased from 1999 to 2005. The percentage of tests

positive for EIA among those tested declined in 2005 (0.01) compared to 1999

(0.06). States with the highest percentage of tests positive for EIA in 1999

(above 0.065) included Arizona, Arkansas, Louisiana, Michigan, Mississippi,

North Dakota, Oklahoma, and Texas; in 2005 States with the highest percentage

of positive tests (above 0.015) included Arkansas, Mississippi, Oklahoma, Texas,

and Utah. The number of EIA tests in a given State is affected by local as well as

intra- and interstate movement requirements and can vary over time based on

changes in regulations and movement patterns.
Section II: Specific Disease Surveillance in the U.S. Equine Industry

12 / Equine 2005

Number tested for EIA and percentage positive for EIA, 1999–2005:

 1999 2005 

Number Tested 

State 

Number 

Tested 

Number 

Positive 

of Those 

Tested 

Percent 

Positive 

of Those 

Tested 2000 2001 2002 2003 2004 

Number 

Tested 

Number 

Positive 

of Those 

Tested 

Percent 

Positive 

of Those 

Tested 

Alabama* 29,037 4 0.014 36,308 35,062 35,723 37,844 37,597 38,442 1 0.003 

Alaska 1,599 0 0.000 1,752 1,607 1,472 1,220 1,391 1,301 0 0.000 

Arizona 6,766 15 0.222 12,866 16,178 14,079 12,662 14,094 13,395 0 0.000 

Arkansas 67,318 148 0.220 66,786 66,368 71,058 71,058 38,030 79,354 35 0.044 

California* 24,580 1 0.004 25,677 30,666 32,834 34,468 34,777 40,499 1 0.002 

Colorado* 18,437 5 0.027 21,434 25,781 18,450 29,279 29,635 27,815 3 0.011 

Connecticut 2,330 0 0.000 2,373 2,447 2,277 2,376 4,933 1,298 0 0.000 

Delaware 4,105 0 0.000 3,488 5,902 6,225 7,028 36,227 6,211 0 0.000 

Florida* 111,776 21 0.019 125,205 130,173 131,598 130,751 129,960 141,140 2 0.001 

Georgia* 63,874 5 0.008 57,448 67,484 66,692 62,265 64,661 59,781 2 0.003 

Hawaii 571 0 0.000 503 318 212 511 689 720 0 0.000 

Idaho 6,122 4 0.065 6,727 13,928 14,485 7,394 13,895 14,739 1 0.007 

Illinois* 61,748 18 0.029 63,825 62,967 59,090 64,686 66,008 64,831 2 0.003 

Indiana* 24,033 13 0.054 19,460 28,744 29,511 33,219 32,622 33,623 1 0.003 

Iowa 12,880 1 0.008 25,392 16,012 18,697 19,215 22,002 22,721 1 0.004 

Kansas* 17,243 3 0.017 14,870 16,255 18,463 17,985 6,737 13,291 2 0.015 

Kentucky* 92,771 6 0.006 102,054 108,825 109,529 108,866 114,469 121,516 2 0.002 

Louisiana* 39,140 109 0.278 46,284 61,953 70,000 30,766 49,632 9,891 3 0.030 

Maine 5,426 0 0.000 5,607 5,325 6,544 6,454 6,087 6,896 1 0.015 

Maryland* 29,070 1 0.003 31,140 30,963 32,534 34,690 39,610 34,371 0 0.000 

Massachusetts 12,079 0 0.000 12,655 11,829 10,512 11,607 9,015 9,622 0 0.000 

Michigan* 19,795 38 0.192 17,666 80,535 72,628 41,010 42,299 64,055 2 0.003 

Minnesota* 38,952 9 0.023 47,700 46,029 48,326 47,354 47,543 47,118 5 0.011 

Mississippi 40,921 31 0.076 28,381 26,228 38,080 36,236 43,517 42,910 9 0.021 

Missouri* 84,910 18 0.021 97,795 75,205 110,224 110,354 115,129 69,750 2 0.003 

Montana* 12,059 2 0.017 15,576 16,872 15,742 16,753 16,752 15,458 1 0.006 

Nebraska 9,387 0 0.000 10,766 12,120 12,682 13,279 13,775 14,148 1 0.007 

Nevada 6,198 4 0.065 7,912 10,174 11,045 14,879 17,229 18,229 0 0.000 

New 

Hampshire 9,787 0 0.000 10,025 10,706 14,844 15,020 16,239 17,701 2 0.011 

New Jersey* 34,386 2 0.006 25,115 15,578 25,549 24,203 28,027 24,855 0 0.000 

New Mexico* 9,366 3 0.032 14,330 14,971 16,940 18,975 17,858 17,913 0 0.000 

New York* 45,411 4 0.009 53,087 50,522 56,242 57,254 58,100 55,784 1 0.002 

North Carolina 48,754 7 0.014 60,548 54,175 70,247 70,656 62,371 72,419 4 0.006 

North Dakota 11,239 22 0.196 10,168 9,798 10,298 11,644 10,352 11,502 1 0.009 

Ohio* 49,774 6 0.012 53,568 54,398 58,988 58,887 59,740 58,782 1 0.002 

Oklahoma* 69,588 141 0.203 61,017 84,325 93,653 103,704 102,475 84,733 23 0.027 

Oregon* 8,094 0 0.000 8,650 10,026 9,412 8,765 9,073 10,206 0 0.000 

Pennsylvania* 44,925 2 0.004 51,594 53,166 75,070 58,407 67,411 88,546 4 0.005 

Rhode Island 1,106 0 0.000 1,042 1,128 429 2,021 2,139 2,282 0 0.000 

South Carolina 29,055 0 0.000 32,760 33,730 35,575 35,016 36,648 37,360 0 0.000 

South Dakota 7,391 0 0.000 9,379 9,219 9,296 9,303 9,817 9,376 0 0.000 

Tennessee* 72,872 23 0.032 66,110 69,536 71,923 80,733 97,577 83,412 4 0.005 

Texas* 181,571 279 0.154 247,035 245,926 258,080 227,225 258,364 312,911 57 0.018 

Utah 12,630 1 0.008 15,573 14,165 13,280 17,012 13,219 14,320 4 0.028 

Vermont 209 0 0.000 208 227 7,263 9,020 9,737 4,866 0 0.000 

Virginia* 49,569 7 0.014 57,695 53,967 49,222 55,380 54,629 93,804 0 0.000 

Washington* 9,421 0 0.000 7,579 10,000 10,083 2,826 14,630 10,566 1 0.009 

West Virginia 9,421 0 0.000 11,599 12,018 13,199 13,902 16,115 17,396 1 0.006 

Wisconsin* 56,068 11 0.020 52,355 52,262 91,554 65,018 71,216 47,859 3 0.006 

Wyoming* 9,643 1 0.010 11,291 12,738 11,719 12,329 11,460 12,907 0 0.000 

 

Total 

(28 States*) 1,301,268 732 0.056 1,441,893 1,555,635 1,679,779 1,589,016 1,694,230 1,683,859 123 0.009 

Total 

(50 States) 1,613,407 965 0.060 1,768,378 1,878,531 2,061,578 1,961,509 2,074,513 2,102,625 183 0.010 

*States participating in NAHMS Equine ‘98 and 2005 studies. 
USDA APHIS VS / 13

 Section II: Specific Disease Surveillance in the U.S. Equine Industry

B. West Nile

Virus (WNV)

1. Background

WNV was first reported in the United States in 1999, with recognized illness due

to the infection in birds, humans, and horses in New York. In 2000, seven States

reported equine WNV cases, with the largest numbers of infection occurring in

New Jersey and New York. In 2001, WNV was reported in 20 States as the virus

moved south from the Northeast through the eastern coastal States. In 2001,

Florida reported the largest number of equine WNV infections with just under

500 cases, over 7 times as many as any other State that year.

From 1999 through 2001, WNV infections were considered an emerging disease

occurrence. Testing for the disease in horses was performed through the

National Veterinary Services Laboratories (NVSL). In 2002, WNV was redefined

by USDA-APHIS-Veterinary Services as an endemic disease to the United

States, and testing moved to regional veterinary diagnostic laboratories as well

as NVSL. The ability to track cases became more challenging as testing and

reporting became more dispersed. Staff at USDA-APHIS-Veterinary Services

have reported the number and State location of equine WNV cases from 1999

through 2005. Current information and surveillance data on WNV is available at:

<http://www.aphis.usda.gov/vs/nahss/equine/wnv>.

Number of U.S. equine WNV cases,1999–2005:

1999 2000 2001 2002 2003 2004 2005 

25 60 738 15,257 5,181 1,406 1,088 

In summer 2001, a conditionally licensed vaccine for prevention of WNV

infection in equids was released. By early 2003, this vaccine had a full license,

and early in 2004 a second equine WNV vaccine became fully licensed. In fall

2006, a third vaccine was licensed. Prior to release of these vaccines, protection

against WNV was limited to efforts that minimized animals’ exposure to insect

vectors.

In 2002, 15,257 equine WNV cases were reported from 41 States. Of these, 9

States had over 500 but less than 1,000 cases and 4 States had more than 1,000

cases in 2002. The highest intensity of reported equine WNV cases moved to the

Central United States.

In 2003, the number of equine WNV cases decreased to 5,181, approximately

one-third the number in 2002. Vaccination of equids, alteration in the ecology of

the virus, heightened vector control efforts, naturally acquired immunity by some

of the equine population, along with the potential for less rigorous diagnostic
Section II: Specific Disease Surveillance in the U.S. Equine Industry

14 / Equine 2005

testing may have contributed to the reduction in number of cases. In 2003, the

largest numbers of cases were reported from Texas, Pennsylvania, Colorado,

and New Mexico, each of which had over 400 cases. In some States, such as

Colorado, the number of equine WNV cases increased from the first year to the

second year. Other States, like Nebraska, reported a decline in the number of

reported cases in the second year. This could be due to an actual change in

number of cases or to increased or decreased recognition, testing, or reporting

of the infection. It is likely that immunization with the WNV vaccines had an

impact on reduction in equine WNV cases, as the number of human cases

actually increased in 2003 compared to 2002 on a national basis.

In 2004 and 2005, there were over 1,000 but fewer than 1,500 equine WNV

cases nationally. In 2004 and 2005, California had the largest number of cases

(more than 450 per year). In 2004, Arizona, Nevada, and Texas each had over

100 cases but fewer than 125 cases. In 2005, only Idaho and California had over

100 cases.

2. Chronological spread of equine WNV across the United States

The maps to the right illustrate the initial movement of WNV outside of New York

from 2000 to 2005. In 2001, the virus spread south and west, with equine WNV

cases reported in Florida and the Midwest. In 2002, WNV cases were reported in

the plains States and as far west as Washington State. In 2003, WNV equine

cases were reported for the first time in California. In 2004, although the total

number of equine WNV cases had declined to just under 1,400 nationally, 1 or

more cases were reported from all but 9 continental States. In 2005, there were

equine WNV cases reported from all but 12 continental States, with most

reporting fewer than 50 cases—if they reported any cases at all. To date, Hawaii

and Alaska have not reported any equine WNV cases.

Control of equine WNV relies on vaccination against the infection in advance of

the vector season, insect control on the premises, and the application of insect

repellants on horses.
USDA APHIS VS / 15

 Section II: Specific Disease Surveillance in the U.S. Equine Industry

Equine WNV Cases, 2000

1-19

20-30

Number of cases

Total U.S. equine WNV cases = 60

Equine WNV Cases, 2001

50-99

100-500

Number of cases

1-49

Total U.S. equine WNV cases = 738

Equine WNV Cases, 2002

500-999

1,000-2,000

Number of cases

100-499

1-99

Total U.S. equine WNV cases = 15,257

Equine WNV Cases, 2003

500-1,000

Number of cases

100-499

1-99

Total U.S. equine WNV cases = 5,181

Equine WNV Cases, 2004

100-499

500-1,000

Number of cases

1-99

Total U.S. equine WNV cases = 1,406

Equine WNV Cases, 2005

50-99

100-500

Number of cases

1-49

Total U.S. equine WNV cases = 1,088
Section II: Specific Disease Surveillance in the U.S. Equine Industry

16 / Equine 2005

C. Vesicular

Stomatitis (VS)

1. Background

VS is a rhabdovirus that causes vesicles and subsequently ulcers primarily on

the lips and in the mouths of infected livestock. In some animals, lesions also

occur on the coronary band and teats. The disease primarily affects horses and

cattle, but can occasionally affect swine and less frequently other animals such

as sheep and camelids. VS is spread by direct contact and by insect vectors. VS

is considered endemic in feral swine on Osabaw Island off the coast of Georgia,

and VS outbreaks occur periodically in the western United States.

Because VS is reportable to the World Organization for Animal Health, and

because the lesions of VS in ruminants or swine are clinically indistinguishable

from foot-and-mouth disease (FMD), USDA initiates foreign animal disease

investigations in response to outbreaks. Horses are not affected by FMD, so

FMD is not considered a potential cause of VS in horses. Premises with

confirmed VS are quarantined until 21 days after verification that lesions in

affected animals have healed.

2. Summary statistics, 1995–2005

Five VS outbreaks occurred in the United States from 1995 through 2005. New

Mexico and Colorado had VS cases in each of the five most recent outbreaks. In

2005, nine States had premises with livestock affected with VS. This was the

largest outbreak of VS in the past decade, based on both number of premises

affected and number of States with premises impacted. Wyoming had the largest

number of premises with VS in 2005, followed by Utah and Colorado. The

USDA’s National Surveillance Unit (NSU) provides a Web site with frequent

updates on the status of VS in the United States. The Web site at

<http://www.aphis.usda.gov/vs/nahss/equine/vsv/> is an excellent source of

current and background information on VS and methods of testing.
USDA APHIS VS / 17

 Section II: Specific Disease Surveillance in the U.S. Equine Industry

a. Number of premises positive for VS (all species) in the United States,

1995–2005:

State 19951 19972 19983 20044 20054

Arizona 1 2 15 0 27 

Colorado 165 273 102 199 100 

Idaho 0 0 0 0 2 

Montana 0 0 0 0 46 

Nebraska 0 0 0 0 3 

New 

Mexico 186 67 12 80 23 

Texas 1 0 1 15 1 

Utah 6 38 0 0 104 

Wyoming 8 0 0 0 139 

Total 367 380 130 294 445 

1

Bridges VE, et al., 1997. Review of the 1995 vesicular stomatitis outbreak in the western United 

States, Jour Am Vet Med Assoc 211(5):557. 2

McCluskey BJ, et al., 1999. Review of the 1997 outbreak of vesicular stomatitis in the western 

United States, Jour Am Vet Med Assoc 215(9):1260. 3

McCluskey BJ, 2003. Epidemiology of vesicular stomatits viruses in the southwestern United 

States. Ph.D. thesis, Colorado State University, p. 12. 4

USDA National Center for Animal Health Surveillance, National Surveillance Unit, 

http://www.aphis.usda.gov/vs/nahss/equine/vsv/

b. Number of VSV-positive equids in 2005, by State:*

State 

AZ CO ID MT NE NM TX UT WY Total 

30 89 6 112 1 27 2 122 195 584 

*USDA National Center for Animal Health Surveillance, National Surveillance Unit, 

http://www.aphis.usda.gov/vs/nahss/equine/vsv/ 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

18 / Equine 2005

Section III: Management and Health Changes in the U.S. Equine Industry,

1998-2005

1. Background

NAHMS’ first national study of the U.S. equine industry, Equine ’98, was based

on selection criteria to represent any equine operation with 1 or more equids in

28 States. The sample provided 2,904 participating operations. The 28-State

target population represented 78.2 percent of U.S. horses and ponies and 78.0

percent of farms with horses and ponies.

Equine 2005 focused on equine operations with 5 or more equids from the same

28 States. The sample provided 3,349 participating operations. The 28-State

target population represented 78.0 percent of equids and 78.6 percent of

operations with 5 or more equids in the United States.

Some estimates in this report are compared to Equine ‘98, NAHMS previous

equine study. Therefore, estimates comparing the 2 study periods are based on

3 points of commonality: same 28 States, data collection performed by NASS

enumerators, and same reference population of 5 or more equids. For the

evaluation of changes and trends, the data used to generate estimates based on

the Equine ’98 study were re-analyzed to represent operations with five or more

equids present on January 1, 1998.

The U.S. equine population is difficult to enumerate because of the diversity of

the equine industry, the geographic breadth of the equine population, and the

suburban areas not included in the traditional livestock enumeration. In addition,

interpretation of changes in estimates among two national studies conducted

between 1998 and 2005 is difficult and may be speculative in nature. Differences

may occur in the factors being measured, e.g., true secular time trends in the

equine industry, changes in question wording, and random variation. These

differences have been documented to aid in interpretation.

Most data are owner-reported and may vary according to recollection, quality of

health records, and consistency of the interpretation of questions. These

concerns are minimized by extensively training interviewers, pretesting all

questionnaires, and validating data.
USDA APHIS VS / 19

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

FL

NM

DE MD

TX OK

KS

NE

SD

ND

MT

WY

CO

UT

ID

AZ

NV

WA

CA

OR

KY

ME

NY

PA

MI

VT NH

MA

RI CT

VA

WV

OH IN

IL

NC

TN

SC

MS AL

AR

LA

MO

IA

MN

WI

NJ

GA

States Participating in Equine '98 and Equine 2005 

CA

WA

OR

NV

ID

UT

NM

AZ

WY

MT

CO

ND

SD

NE

KS

OK TX

MN

IA

MO

AR

LA

WI

IL

TN

KY

MS

IN

MI

OH

AL

FL

GA SC

NC

VA

WV

PA

MD DE

NY RI

VT

NH

ME

MA

CT

NJ

Shaded States = Participating States
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

20 / Equine 2005

Equid: Animal of the family Equidae. Only domestic horses, miniature horses,

ponies, mules, donkeys/burros, and zedonks (zebra-donkey cross) were

included.

Foal: Equid less than 6 months of age.

Horse: Domestic equid generally more than 14 hands (56 inches) high at the

shoulder (near the last hairs of the mane). An equid less than 14 hands high may

also be considered a horse if its breed registry defines it as such (other than

miniature horse). Horses include light breeds (e.g., Arabian, Quarter Horse,

Appaloosa, Morgan, Trakehner, etc.) and draft horses (e.g., Clydesdale, Belgian,

and Percheron).

N/A: Not applicable.

Operation: An area of land managed as a unit by an individual, partnership, or

hired manager.

Operator: The person responsible for the day-to-day decisions on the operation.

Operation average: A single value for each operation is summed over all

operations reporting and divided by the number of operations reporting.

Perceived cause (of illness or death): Causes of illnesses or deaths were

derived from observations of clinical signs reported by participants and not

necessarily confirmed by a veterinarian or laboratory testing.

Percent equids: The total number of equids with a certain attribute, divided by

the total number of equids.

Primary function of operation: The main purpose of the operation, i.e.,

boarding/training, breeding farm, farm/ranch, and residence with equids for

personal use.

Primary use of equids: What the majority of horses on the operation are used

for, i.e., pleasure, lessons/school, show/competition, breeding, racing, farm/

ranch work.

2. Terms
USDA APHIS VS / 21

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

Population estimates: Estimates in this report are provided with a measure of

precision called the standard error. A 95-percent confidence interval can be

created with bounds equal to the estimate, plus or minus two standard errors. If

the only error is sampling error, the confidence intervals created in this manner

will contain the true population mean 95 out of 100 times. In the example to the

left, an estimate of 7.5 with a standard error of 1.0 results in limits of 5.5 to 9.5

(two times the standard error above and below the estimate). The second

estimate of 3.4 shows a standard error of 0.3 and results in limits of 2.8 and 4.0.

Alternatively, the 90-percent confidence interval would be created by multiplying

the standard error by 1.65 instead of 2. Most estimates in this report are rounded

to the nearest tenth. If rounded to 0, the standard error was reported (0.0). If

there were no reports of the event, no standard error was reported (—).

Regions

• South: Alabama, Florida, Georgia, Kentucky, Louisiana, Maryland, Oklahoma,

Tennessee, Texas, and Virginia

• Northeast: New Jersey, New York, Ohio, and Pennsylvania

• West: California, Colorado, Montana, New Mexico, Oregon, Washington, and

Wyoming

• Central: Illinois, Indiana, Kansas, Michigan, Minnesota, Missouri, and

Wisconsin

Resident equid: An equid that spent or was expected to spend more time at the

operation than at any other operation, whether or not it was present at the time of

the interview. The operation was its home base.

Size of operation: Size groupings were based on number of equids present on

July 1, 1998, for the Equine ’98 study and July 1, 2005, for the Equine 2005

study. Size of operation was categorized as small (5-9 equids), medium (10-19

equids), and large (20 or more equids). For the purpose of this report, small

operations include operations that had five or more equids per the NASS list

frame (primarily comprised of equine information from the 2002 Census of

Agriculture) but had fewer than five equids on July 1, 2005; approximately 70

percent of these operations had three to four equids on July 1, 2005.

Standard Errors

(1.0)

10

9

8

7

6

5

4

3

2

1

0 (0.3)

Examples of a 95% Confidence Interval

95% Confidence 

Intervals
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

22 / Equine 2005

A. General 1. Primary function of operations

The percentage of operations with a primary function of equine boarding/training

stable was higher in 1998 compared to 2005 (10.0 percent and 5.9 percent,

respectively). The percentage of operations with a primary function of farm/ranch

was lower in 1998 compared to 2005. In 2005, the selection of operations was

based on operations that had five or more equids per the NASS list frame of

places that met the definition of a “farm” (primarily comprised of equine

information from the 2002 Census of Agriculture) which may explain the higher

percentage of operations in 2005 with a primary function farm/ranch (see p. 2 for

discussion on definition of a farm).

Percentage of operations by primary function of operation:

 Percent Operations 

1998 2005 

Primary Function Percent Std. Error Percent Std. Error 

Equine boarding stable/training* 10.0 (1.4) 5.9 (0.4) 

Equine breeding farm 15.1 (1.7) 14.4 (0.7) 

Farm/ranch 30.1 (2.3) 40.3 (1.0) 

Residence with equids for personal 

use (show, pleasure, etc.) 38.3 (2.7) 37.0 (1.0) 

Other 6.5 (1.2) 2.4 (0.3) 

Total 100.0 100.0 

*1998 choices: “Boarding stable only,” “Training facility only,” and “Boarding stable/training.” 
USDA APHIS VS / 23

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

APHIS photo by Charles Kerlee
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

24 / Equine 2005

2. Primary use of equids

In 1998 and 2005, nearly one of two operations used equids primarily for

pleasure (46.1 and 45.7 percent, respectively) and about one of five operations

used equids primarily for farm/ranch work (18.7 and 24.8 percent, respectively).

The percentage of operations where the primary use of equids was racing

decreased from 4.6 percent in 1998 to 1.4 percent in 2005. In 1998, lessons/

school was not offered as a choice for primary use of equids, which may account

for the lower percentage of operations in the “other” category in 2005 than in

1998.

Percentage of operations by primary use of equids:

Percent Operations 

1998 2005 

Primary Use Percent Std. Error Percent Std. Error 

Pleasure 46.1 (2.6) 45.7 (1.0) 

Lessons/school N/A 1.4 (0.2) 

Show/competition 

(not betting) 10.4 (1.5) 9.6 (0.6) 

Breeding 15.8 (1.8) 15.9 (0.7) 

Racing 4.6 (1.1) 1.4 (0.2) 

Farm/ranch work 18.7 (1.9) 24.8 (0.9) 

Other 4.4 (0.9) 1.2 (0.2) 

Total 100.0 100.0 
USDA APHIS VS / 25

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

3. Equid distribution

The percentage of large operations was higher in 1998 than in 2005. This

decrease in operation size is consistent with the Census of Agriculture data

reported on p. 4.

a. Percentage of operations by size of operation:

The percentage of equids on large operations decreased from 39.4 percent in

1998 to 29.7 percent in 2005.

b. Percentage of equids by size of operation:

 Percent Equids 

 1998 2005 

Size of Operation* 

(Number of Equids) Percent Std. Error Percent Std. Error 

Small (5 to 9 ) 34.1 (2.2) 36.1 (0.8) 

Medium (10 to 19) 26.5 (2.4) 34.2 (1.0) 

Large (20 or more) 39.4 (2.6) 29.7 (1.1) 

Total 100.0 100.0 

*See p. 21 for detailed description of size breakout for 1998 and 2005.

 Percent Operations 

 1998 2005 

Size of Operation* 

(Number of Equids) Percent Std. Error Percent Std. Error 

Small (5 to 9) 63.1 (2.4) 66.1 (0.8) 

Medium (10 to 19) 23.7 (2.2) 26.1 (0.8) 

Large (20 or more) 13.2 (1.4) 7.8 (0.3) 

Total 100.0 100.0 

*See p. 21 for detailed description of size breakout for 1998 and 2005. 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

26 / Equine 2005

4. Type of equid

In both 1998 and 2005, over 95 percent of operations had full-size horses. The

percentages of operations by type of equid were similar in 1998 and 2005.

a. Percentage of operations by type of equid:

 Percent Operations 

 1998 2005 

Type of Equid Percent Std. Error Percent Std. Error 

Donkeys or burros 7.4 (1.4) 12.2 (0.7) 

Mules 9.5 (1.4) 7.9 (0.5) 

Ponies 18.2 (1.8) 15.7 (0.7) 

Miniature horses 5.4 (1.0) 7.5 (0.5) 

Horses 

(excluding miniature horses) 98.4 (0.5) 95.6 (0.4) 

Other equids 0.2 (0.1) 0.3 (0.1) 

0

15

30

45

2005

1998

34.1

36.1

26.5

34.2

39.4

29.7

Small (5 to 9) Medium (10 to 19) Large (20 or more)

Size of Operation* (Number of Equids)

*Seem p. 21 for detailed description

of size breakouts for 1998 and 2005

Percentage of Equids by Size of Operation

Percent
USDA APHIS VS / 27

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

Overall, the percentages of equids by type were similar in 1998 and 2005 for

most equid types. The percentage of miniature horses increased slightly from 1.8

percent of equids in 1998 to 3.9 percent in 2005.

b. Percentage of equids by type of equid:

 Percent Equids 

1998 2005 

Type of Equid Percent Std. Error Percent Std. Error 

Donkeys or burros 2.0 (0.5) 3.7 (0.3) 

Mules 2.4 (0.4) 2.3 (0.2) 

Ponies 4.9 (0.7) 3.4 (0.2) 

Miniature horses 1.8 (0.3) 3.9 (0.4) 

Horses (excluding 

miniature horses) 88.9 (1.0) 86.6 (0.5) 

Other equids 0.0 (0.0) 0.1 (0.0) 

Total 100.0 100.0 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

28 / Equine 2005

The percentage of resident equids paralleled the percentage of overall equids by

type in 1998 and 2005. The percentage of miniature horses considered residents

increased slightly from 1.9 percent of equids in 1998 to 3.6 percent in 2005. For

this report, a resident equid was an equid that spent or was expected to spend

more time at the operation than at any other operation, whether or not it was

present at the time of the interview. The operation was its home base.

c. Percentage of resident equids by type of equid:

 Percent Resident Equids 

1998 2005 

Type of Equid Percent Std. Error Percent Std. Error 

Donkeys or burros 2.1 (0.5) 3.8 (0.3) 

Mules 2.2 (0.4) 2.4 (0.2) 

Ponies 4.8 (0.7) 3.4 (0.2) 

Miniature horses 1.9 (0.4) 3.6 (0.3) 

Horses (excluding 

miniature horses) 89.0 (1.0) 86.7 (0.5) 

Other equids 0.0 (0.0) 0.1 (0.0) 

Total 100.0 100.0 
USDA APHIS VS / 29

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

5. Age of resident equids

The percentage of the equine population 20 years of age or older increased from

5.6 percent in 1998 to 7.6 percent in 2005. The percentages of equids aged 5 to

less than 20 years were similar in 1998 and 2005.

Percentage of resident equids by age:

 Percent Resident Equids 

1998 2005 

Age Percent Std. Error Percent Std. Error 

Birth to 30 days 0.8 (0.1) 

31 days but less 

than 6 months 

6.8 (0.5) 

7.4 (0.3) 

6 months to less 

than 5 years 30.8 (1.2) 27.5 (0.5) 

5 years to less 

than 20 years 55.4 (1.2) 56.7 (0.5) 

20 years to less 

than 30 years 6.9 (0.3) 

30 years or older 

5.6* (0.5) 

0.7 (0.1) 

Unknown** 1.4 (0.6) -- (--) 

Total 100.0 100.0 

*

The age category in 1998 was 20 or more years for the oldest age option. 

**Unknown age was not offered as an option to respondents in 2005. 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

30 / Equine 2005

6. Identification method

The methods of unique identification (ID) for equids on a given operation were

not mutually exclusive, so that more than one form of ID could have been used

on an operation or on the same equid. An ID unique on the home operation may

not be unique off the home operation. The percentage of operations using no

unique ID for at least one equid was lower in 2005 (49.3 percent) than in 1998

(59.6 percent). However, these percentages may have been influenced by the

addition of “Coggins or other EIA test” and “passport” as methods of ID in the

2005 questionnaire, which were not options in the 1998 questionnaire. For the

most part, the percentages of operations using various methods of unique ID

were similar in 1998 and 2005, except that a smaller percentage of operations

used tattoo as a form of ID in 2005 than in 1998. This could be reflective of the

lower percentage of operations where racing was the primary use of equids in

2005 compared to 1998 (see table p. 24).

a. Percentage of operations that used the following unique ID methods for

resident equids (each equid has a different ID; no two equids have the same ID),

by ID method:

 Percent Operations 

 1998 2005 

ID Method Percent Std. Error Percent Std. Error 

Hot-iron brand 13.9 (1.4) 12.2 (0.6) 

Freeze brand 10.7 (1.3) 13.8 (0.7) 

Microchip 2.1 (0.8) 3.1 (0.3) 

Tattoo 20.8 (2.1) 11.7 (0.6) 

Permanent brand 

inspection (card with 

markings indicated 

or sketch) 6.9 (1.1) 7.5 (0.5) 

Registration papers* 57.0 (2.6) 61.7 (1.0) 

Coggins test 

papers (laboratory 

test results) N/A 40.0 (1.0) 

Halters or collars 

with name or number 3.9 (0.8) 4.1 (0.4) 

Passport N/A 1.1 (0.2) 

Other unique ID 4.8 (0.9) 3.9 (0.4) 

At least one equid 

with no unique ID 59.6 (2.5) 49.3 (1.0) 

No unique ID for 

any equids 28.3 (2.2) 19.2 (0.8) 

*In 1998, category was photograph, sketch, or registration papers instead of registration papers. 
USDA APHIS VS / 31

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

The percentage of equids with no unique ID was lower in 2005 (28.7 percent)

than in 1998 (37.1 percent). However, these percentages may have been

influenced by the addition of “Coggins or other EIA test” and “passport “as

methods of ID in the 2005 questionnaire—which were not options in the 1998

questionnaire—or they may reflect a true increase in the percentage of equids

with unique IDs. The percentage of equids with a freeze brand was slightly higher

in 2005 (5.2 percent) compared to 1998 (2.6 percent).

b. Percentage of resident equids that were uniquely identified with following ID

methods (each equid has a different ID; no two equids have the same ID):

 Percent Resident Equids 

 1998 2005 

ID Method Percent Std. Error Percent Std. Error 

Hot-iron brand 5.6 (0.9) 4.6 (0.4) 

Freeze brand 2.6 (0.4) 5.2 (0.5) 

Microchip 1.1 (0.4) 1.5 (0.2) 

Tattoo 7.5 (0.9) 4.0 (0.3) 

Permanent brand 

inspection (card with 

markings indicated or 

sketch) 5.7 (1.1) 4.0 (0.3) 

Registration papers* 47.4 (2.3) 47.8 (1.0) 

Coggins test 

papers (laboratory 

test results) N/A 27.2 (0.8) 

Halters or collars 

with name or number 3.0 (0.5) 3.6 (0.4) 

Passport N/A 0.3 (0.1) 

Other unique ID 3.9 (0.9) 2.3 (0.3) 

No unique ID 37.1 (2.1) 28.7 (0.8) 

*In 1998, category was photograph, sketch, or registration papers instead of registration papers. 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

32 / Equine 2005

0 10 20 30 40 50 60

2005

1998

Hot-iron brand

Freeze brand

Microchip

Tattoo

Permanent

brand inspection

Registration

papers

Coggins test

papers

Halters or collars

with name or number

Passport

Other

unique ID

Method

Percent

Percentage of Resident Equids that Were Uniquely Identified with the

Following ID Methods

5.6

4.6

2.6

5.2

1.1

1.5

7.5

4.0

5.7

4.0

47.4

47.8

27.2

N/A

3.0

3.6

N/A

0.3

3.9

2.3

No

unique ID

37.1

28.7
USDA APHIS VS / 33

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

B. Health and Health

Management

1. Primary method of recording equine information

The percentage of operations that used computerized records as the primary

method of recording equine health information increased from 4.9 percent of

operations in 1998 to 7.8 percent in 2005. Nearly half of operations in 2005 still

used hand-written notes either in a designated log or on a calendar or check

book as the primary method of record keeping. The percentage of operations

that relied on a veterinarian to maintain equine health records increased from

11.8 percent in 1998 to 20.2 percent in 2005. The percentages of operations with

no written or computerized records were similar in 1998 and 2005, with about

one of four operations reporting no form of written or computerized equine health

records.

Percentage of operations by primary method of recording equine health

information:

 Percent Operations 

 1998 2005 

Method Percent 

Std. 

Error Percent 

Std. 

Error 

Computerized health records 

maintained on the operation 4.9 (0.9) 7.8 (0.5) 

Hand-written in designated log 

(e.g., health card, logbook) 27.7 (2.2) 22.9 (0.9) 

Hand-written notes (e.g., 

calendar, checkbook) 30.3 (2.2) 25.6 (0.9) 

Operation records 

maintained by veterinarian 11.8 (1.6) 20.2 (0.9) 

No written or 

computerized records 25.3 (2.2) 23.5 (0.9) 

Total 100.0 100.0 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

34 / Equine 2005

0

10

20

30

40

2005

1998

Percent

Method

Percentage of Operations by Primary Method of Recording Equine Health

Information

Computerized

health records

maintained on

operation

Hand-written

in designated

log

Operation

records

maintained by

veterinarian

No written or

computerized

records

Hand-written

notes

4.9

7.8

27.7

22.9

30.3

25.6

11.8

20.2

25.3

23.5

2. Testing

The percentage of operations that performed fecal testing for parasites during

the previous 12 months decreased from 20.0 percent in 1998 to 13.5 percent in

2005. A lower percentage of operations performing fecal testing may reflect a

reliance on the effectiveness of parasite control methods or a lack of recognized

parasite problems. The percentages of operations that performed feed/pasture

analysis and water analysis were similar in 1998 and 2005.

Percentage of operations by testing performed during the previous 12 months:

 Percent Operations 

1998 2005 

Test Percent Std. Error Percent Std. Error 

Fecal test for parasites 20.0 (1.8) 13.5 (0.7) 

Feed or pasture analysis 7.9 (1.1) 8.1 (0.5) 

Water analysis 7.5 (1.4) 7.8 (0.5) 
USDA APHIS VS / 35

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

3. Familiarity with EIA

The percentage of operators that had at least heard of EIA increased from 1998

to 2005. However, the percentages of operators that indicated they were

knowledgeable about EIA were similar in 1998 and 2005. USDA-APHISVeterinary Services began an educational initiative regarding EIA in 1996, which

included an educational video and brochure. It is possible this initiative, along

with other EIA educational efforts, improved operators’ familiarity with EIA.

Percentage of operations by familiarity with EIA:

Percent Operations 

1998 2005 

Familiarity Percent Std. Error Percent Std. Error 

Had not heard of it before 16.7 (1.9) 9.8 (0.6) 

Recognized the 

name, not much else 14.5 (1.6) 18.7 (0.8) 

Knew some basics 23.9 (2.1) 25.9 (0.9) 

Knowledgeable 44.9 (2.7) 45.6 (1.0) 

Total 100.0 100.0 

0

10

20

30

40

50

60

2005

1998

Had not heard

of it before

Recognized the

name, not

much else

Knew some

basics

Knowledgeable

16.7

9.8

14.5

18.7

23.9

25.9

44.9 45.6

Percent

Familiarity

Percentage of Operations by Familiarity with EIA
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

36 / Equine 2005

4. EIA testing

The percentages of operations that tested at least one equid for EIA were similar

in 1998 and 2005, with 58.7 percent of operations testing at least one equid in

1998 and 54.1 percent doing so in 2005.

a. Percentage of operations that performed at least one Coggins or other test for

EIA during the previous 12 months:

Percent Operations 

1998 2005 

Percent Std. Error Percent Std. Error 

58.7 (2.6) 54.1 (1.0) 

In the following table, the overall percentage of all equids tested for EIA is

presented. The overall percentages of equids tested were similar in 1998 and

2005.

b. Percentage of resident equids tested for EIA on all operations during the

previous 12 months:

Percent Resident Equids 

1998 2005 

Percent Std. Error Percent Std. Error 

36.6 (2.0) 37.6 (0.8) 

In contrast to the previous table, this table presents the percentage of equids

tested on operations that tested at least one equid during the previous 12

months. The percentages were similar in 1998 and 2005.

c. For operations that tested for EIA, percentage of resident equids tested:

Percent Resident Equids 

1998 2005 

Percent Std. Error Percent Std. Error 

55.6 (2.5) 59.1 (1.0) 
USDA APHIS VS / 37

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

The average cost of an EIA test increased from $22.95 in 1998 to $27.33 in

2005, a $4.38 (19.1 percent) difference.

d. For operations that tested for EIA, average cost per test (including call fee or

cost of transportation):

The primary reasons for testing for EIA were similar in 1998 and 2005, with a

slightly lower percentage of operations testing primarily for change of ownership

in 2005 compared to 1998, and a slightly higher percentage of operations testing

for personal knowledge in 2005 compared to 1998.

e. For operations that tested for EIA, percentage of operations by primary reason

for testing:

Percent Operations 

1998 2005 

Primary Reason for Testing Percent 

Std. 

Error Percent 

Std. 

Error 

Change of ownership within State 14.5 (2.2) 8.2 (0.7) 

Show or event 

requirement within State 42.2 (3.0) 38.0 (1.3) 

Facility (e.g., boarding, 

breeding) requirement within State N/A* 11.1 (0.8) 

Interstate movement 

(between two or more States) 21.5 (2.5) 19.2 (1.1) 

International movement 1.3 (0.6) 0.3 (0.1) 

Personal knowledge 12.1 (1.8) 18.8 (1.1) 

Suspicion of equine illness 1.7 (0.8) 1.0 (0.3) 

Other 6.7 (1.4) 3.4 (0.5) 

Total 100.0 100.0 

*Facility not an option in 1998. 

Average Cost per Test 

1998 2005

Average Std. Error Average Std. Error 

$22.95 (0.67) $27.33 (0.59) 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

38 / Equine 2005

5. Vaccinations

The percentages of operations that vaccinated resident equids during the

previous 12 months were similar in 1998 and 2005: about three-fourths of

operations had given at least some type of vaccine to resident equids during the

previous 12 months.

a. Percentage of operations that administered any vaccine to resident equids

during the previous 12 months:

Percent Operations 

1998 2005 

Percent Std. Error Percent Std. Error 

75.1 (2.4) 75.9 (0.9) 

A veterinarian was the primary source of equine vaccines in both 1998 and 2005.

The percentage of operations that used a veterinarian as the primary source of

vaccines increased from 62.4 percent in 1998 to 76.0 percent in 2005. The

percentage of operations that used a feed store or veterinary supply store

decreased from 23.0 percent in 1998 to 15.6 percent in 2005.

b. For operations that administered any vaccine to resident equids during the

previous 12 months, percentage of operations by primary source of vaccines:

Percent Operations 

 1998 2005 

Primary Source Percent Std. Error Percent Std. Error 

Veterinarian 62.4 (2.7) 76.0 (1.0) 

Feed store or 

veterinary supply store 23.0 (2.2) 15.6 (0.9) 

Catalog/Internet* 13.9 (2.1) 7.4 (0.6) 

Other 0.7 (0.3) 1.0 (0.2) 

Total 100.0 100.0 

*In 1998, the catalog/Internet choice did not include Internet. 
USDA APHIS VS / 39

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

0

20

40

60

80

2005

1998

62.4

76.0

23.0

15.6 13.9

7.4

0.7 1.0

Veterinarian Feed store or

veterinary

supply store

Catalog/

Internet*

Other

Percent

Source

For Operations that Administered any Vaccine to Resident Equids During the

Previous 12 months, Percentage of Operations by Primary Source of Vaccines

*In 1998, the catalog/Internet

 choice did not include Internet.
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

40 / Equine 2005

The percentage of operations where a veterinarian administered the majority of

vaccines increased from 40.7 percent in 1998 to 50.3 percent in 2005. In

contrast, the percentage of operations where operation personnel (including

operator) administered the majority of vaccines decreased from 47.9 percent in

1998 to 33.3 percent in 2005.

c. For operations that administered any vaccine to resident equids during the

previous 12 months, percentage of operations by person who administered the

majority of vaccines:

The most commonly used vaccines based on the percentages of all operations

vaccinating any equids during the previous 12 months were similar in 1998 and

2005, with tetanus, eastern and western equine encephalitis (EEE/WEE), and flu

vaccines each being administered by over 50 percent of operations. A lower

percentage of operations administered flu, tetanus, and EEE/WEE vaccines in

2005 than in 1998. In order to determine the possible reason for this difference,

the data for 2005 were analyzed to determine the percentage of operations

giving just one type of vaccine and what vaccine was given. The majority of

operations that administered only one vaccine gave WNV vaccine. Thus,

operations that gave only WNV vaccine did not report giving other vaccines in

2005. WNV was first reported in the United States in 1999, and at the time there

was no available vaccine to prevent the disease in equids. Since 1999, WNV has

been responsible for the largest outbreak of an arboviral encephalomyelitis ever

reported. Much information on this disease and methods of prevention have

been provided to equine owners and the general public, which may account for

the common use of WNV vaccine.

A higher percentage of operations reported using vaccine for equine viral arteritis

(EVA) in 2005 than in 1998. Several States have a control program for EVA for

their Thoroughbred populations, and there has been educational material on EVA

provided from USDA-APHIS-Veterinary Services, which may account for the

Percent Operations 

1998 2005 

Person Percent Std. Error Percent Std. Error 

Veterinarian 40.7 (3.0) 50.3 (1.2) 

Operation personnel 

(including operator) 47.9 (3.2) 33.3 (1.1) 

Equine owner (not operator) 10.4 (1.7) 16.1 (0.9) 

Other 1.0 (0.5) 0.3 (0.1) 

Total 100.0 100.0 
USDA APHIS VS / 41

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

increased use of this vaccine. For more information on EVA, visit the NSU’s

Web site at <http://www.aphis.usda.gov/vs/nahss/equine/>. The vaccine for

equine protozoal myeloencephalopathy (EPM) was not available in 1998; 3.6

percent of operations reported vaccinating equids with EPM vaccine in 2005.

Anthrax was not listed as a choice on the 1998 questionnaire but was in the 2005

questionnaire, with 1.8 percent of operations reporting use of this vaccine for

their equids in 2005. A higher percentage of operations used vaccine for

strangles in 2005 than in 1998. Since 1998, an additional type of vaccine

(intranasal administration) for prevention of strangles was released. This new

vaccine, along with increased concern regarding this disease, may account for

increased reported use.

d. Percentage of operations that administered vaccines for the following

diseases to one or more equids during the previous 12 months:

Percent Operations 

1998 2005 

Disease Pct. Std. Error Pct. Std. Error 

Flu (influenza) 66.4 (3.7) 54.1 (1.0) 

Strangles (Strep. equi) 19.4 (2.8) 26.8 (0.9) 

Rhinopneumonitis (herpesvirus) 51.6 (3.9) 47.5 (1.0) 

Rabies 23.9 (3.0) 33.1 (1.0) 

West Nile virus* N/A 63.8 (1.0) 

Eastern and western equine 

encephalitis* 65.5 (3.6) 56.4 (1.0) 

Tetanus 76.5 (3.3) 60.7 (1.0) 

Equine viral arteritis (EVA) 2.9 (0.9) 11.7 (0.7) 

Venezuelan equine 

encephalitis* (VEE) N/A 17.9 (0.8) 

Clostridium perfringens (C&D) 0.6 (0.3) 2.5 (0.3) 

Potomac horse fever (PHF) 16.8 (2.8) 10.6 (0.6) 

Rotavirus 2.4 (0.9) 4.2 (0.4) 

Anthrax* N/A 1.8 (0.3) 

Equine protozoal 

myeloencephalopathy* (EPM) N/A 3.6 (0.4) 

Other 0.1 (0.0) 0.5 (0.1) 

*The 1998 question did not separate encephalitis by EEE/WEE and VEE, and did not include WNV, 

anthrax, or EPM. The 1998 question offered VSV and leptospirosis as options. The 1998 question 

did not offer “don’t know” as an option for vaccinations used.
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

42 / Equine 2005

6. Foal health

The percentages of operations with foals affected by the conditions listed in the

table to the right were similar in 1998 and 2005, with the exception of digestive

problems other than colic, which decreased from 13.1 percent of operations in

1998 to 5.7 percent in 2005. Additional categories for foal conditions were added

to the Equine 2005 questionnaire: failure to get milk, dystocia or birthing

problem, and fever of undetermined origin. Thus, no comparisons with 1998 can

be made for these categories. In addition, in 2005 participants were given the

option to list problems not specified on the list; “other” foal conditions included

mare sick/foal sick, did not know what the problem was, weak, albino,

complication of castration, and hernia.
USDA APHIS VS / 43

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

a. For operations that had any resident foals less than 6 months of age during

the previous 12 months, percentage of operations where foals became affected

with the following conditions:

 Percent Operations 

 1998 2005 

Condition Percent Std. Error Percent Std. Error 

Colic 2.7 (1.0) 2.8 (0.5) 

Other digestive 

problems (e.g., diarrhea) 13.1 (2.8) 5.7 (0.7) 

Respiratory problems 

(e.g., pneumonia, strangles, 

Rhodococcus equi, etc.) 4.8 (1.7) 5.2 (0.7) 

Eye problems 1.9 (0.7) 1.4 (0.3) 

Skin problems 0.7 (0.4) 1.2 (0.3) 

Reproductive tract 

problems (e.g., hermaphrodite, 

cryptorchid) 2.0 (1.2) 0.5 (0.2) 

Behavioral problems (e.g., 

unusual, affects use or safety) 0.1 (0.1) 0.3 (0.2) 

Injury/wounds/trauma 12.5 (2.1) 13.9 (1.1) 

Lameness, leg, or hoof 

problems (could not be 

used for intended purpose 

without treatment)* 3.2 (0.8) 3.6 (0.6) 

Neurologic problems 0.4 (0.2) 0.4 (0.2) 

Infectious disease unrelated 

to specific body system 

(septicemia, blood infection) 0.9 (0.5) 1.6 (0.4) 

Chronic weight loss 1.0 (0.5) 0.2 (0.1) 

Overweight/obese 0.3 (0.3) 0.2 (0.1) 

Failure to get milk or 

colostrum from mare/dam N/A 3.6 (0.6) 

Complications from 

birthing/dystocia N/A 1.2 (0.2) 

Fever of undetermined origin N/A 1.2 (0.3) 

Other N/A 1.3 (0.4) 

*Question from 1998 was worded as leg or hoof problems instead of lameness, leg, or hoof problems 

(2005). 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

44 / Equine 2005

The percentages of foals affected with the conditions listed in the table to the

right were similar in 1998 and 2005, with the exception of digestive problems

other than colic, which decreased from 21.5 percent of foals in 1998 to 6.3

percent in 2005. It is possible that operators reported serious problems or

problems that were more recent rather than those that occurred many months

prior to the interview or were not as serious or costly. Additional categories for

foal conditions were added to the Equine 2005 questionnaire: failure to get milk,

dystocia or birthing problem, and fever of undetermined origin. Thus, no

comparisons with 1998 can be made for these categories. Injury/wounds/trauma,

digestive problems other than colic, and respiratory problems each affected over

4 percent of foals in both 1998 and 2005.

APHIS photograph by Charles Kerlee
USDA APHIS VS / 45

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

 Percent Foals 

 1998 2005 

Condition Percent Std. Error Percent Std. Error 

Colic 2.1 (0.7) 4.2 (2.5) 

Other digestive problems 

(e.g., diarrhea) 21.5 (5.2) 6.3 (0.9) 

Respiratory problems 

(e.g., pneumonia, strangles, 

Rhodococcus equi, etc.) 9.3 (4.5) 

4.3 

(0.6) 

Eye problems 1.3 (0.4) 1.0 (0.2) 

Skin problems 0.8 (0.3) 0.8 (0.3) 

Reproductive tract 

problems (e.g., 

hermaphrodite, cryptorchid) 1.3 (0.7) 

0.3 

(0.1) 

Behavioral problems (e.g., 

unusual, affects use or safety) 0.1 (0.0) 0.2 (0.1) 

Injury, wounds, or trauma 12.2 (2.6) 9.2 (0.8) 

Lameness, leg, or hoof 

problems (could not be 

used for intended purpose 

without treatment)* 2.4 (0.5) 

2.6 

(0.4) 

Neurologic problems 0.4 (0.2) 5.7** (5.1) 

Infectious disease unrelated to 

specific body system 

(septicemia, blood infection) 0.8 (0.4) 

1.0 

(0.3) 

Chronic weight loss 0.7 (0.3) 0.1 (0.1) 

Overweight/obese 0.4 (0.4) 0.2 (0.1) 

Failure to get milk or 

colostrum from mare/dam N/A 2.0 (0.3) 

Complications from 

birthing/dystocia N/A 1.0 (0.2) 

Fever of undetermined origin N/A 0.8 (0.2) 

Other N/A 0.8 (0.2) 

*Question from 1998 was worded as leg or hoof problems instead of lameness, leg, or hoof problems 

(2005). 

**Because of the large standard error in 2005, it is difficult to determine if there was a difference in 

neurologic problems between 1998 and 2005. 

b. For operations that had any resident foals less than 6 months of age during

the previous 12 months, percentage of foals affected with the following

conditions:
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

46 / Equine 2005

7. Equid health

In general, the percentages of operations where equids 6 months of age or older

were affected with the conditions listed in the table to the right were higher in

1998 than in 2005. It is possible that there was a true decline in the percentage

of operations with one or more equids with these conditions, or it may be that

operations in 2005 were less likely to report the occurrence of some of these

problems. In the 2005 questionnaire, the question regarding the number of

equids with each of the listed conditions was preceded by a question about

antimicrobial use. Therefore, some respondents may have been more likely to

report conditions for which they gave treatment. Liver/kidney problem and cancer

were not choices in the 1998 questionnaire. Thus, no comparisons with 1998 and

2005 can be made for these categories. In addition, in 2005 participants were

given the option to list problems not specified on the list; “other” equid conditions

included envenomation (snake or insect bite) and endocrine disorders.
USDA APHIS VS / 47

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

a. For operations that had any resident equids 6 months of age or older during

the previous 12 months, percentage of operations where equids became

affected with the following conditions:

 Percent Operations 

 1998 2005 

Condition Percent Std. Error Percent Std. Error 

Colic 26.5 (2.2) 10.4 (0.6) 

Other digestive problems 

(e.g., diarrhea) 5.0 (1.0) 2.4 (0.3) 

Dental problems N/A 5.3 (0.5) 

Respiratory problems 12.3 (1.7) 9.1 (0.6) 

Eye problems 12.5 (1.5) 6.5 (0.5) 

Skin problems 11.2 (1.5) 5.4 (0.5) 

Reproductive problems 

(e.g., infertility, dystocia) 7.5 (1.2) 3.3 (0.4) 

Behavioral problems (e.g., 

unusual, affects use or 

safety) 2.9 (0.8) 1.0 (0.2) 

Injury, wounds, or trauma 29.1 (2.2) 25.7 (0.9) 

Lameness, leg, or hoof 

problems (could not be 

used for intended purpose 

without treatment)* 23.5 (2.1) 15.5 (0.8) 

Neurologic problems (e.g., 

spinal problem, wobblers, 

seizure, West Nile virus, 

EPM) 3.0 (0.8) 0.9 (0.2) 

Infectious disease 

unrelated to specific body 

system (septicemia, blood 

infections) 2.5 (0.7) 1.6 (0.3) 

Chronic weight loss 5.6 (1.1) 1.4 (0.2) 

Overweight/obese 5.5 (1.3) 3.4 (0.4) 

Liver or kidney disease N/A 0.5 (0.1) 

Cancer N/A 1.1 (0.2) 

Other N/A 1.8 (0.3) 

*Question from 1998 was worded as leg or hoof problems instead of lameness, leg, or hoof 

problems (2005). 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

48 / Equine 2005

The percentages of equids with the conditions listed in the table to the right were

similar in 1998 and 2005. One exception was the incidence of colic, which

decreased from 5.0 percent of resident equids affected in 1998 to 1.9 percent in

2005. It is possible that there was a true decline in the percentage of equids with

colic, or it may be that operations in 2005 were less likely to report the

occurrence of colic. In the 2005 questionnaire, the question regarding the

number of equids with each of the listed conditions was preceded by a question

about antimicrobial use. Therefore, some respondents may have been more

likely to report conditions for which they gave treatment. Liver/kidney problem

and cancer were not choices in the 1998 questionnaire. Thus, no comparisons

with 1998 and 2005 can be made for these categories.

APHIS photograph by Charles Kerlee
USDA APHIS VS / 49

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

 Percent Equids 

 1998 2005 

Condition Percent Std. Error Percent Std. Error 

Colic 5.0 (0.6) 1.9 (0.1) 

Other digestive problems 

(e.g., diarrhea) 0.8 (0.2) 0.5 (0.1) 

Dental problems N/A 1.6 (0.2) 

Respiratory problems 2.9 (0.5) 1.9 (0.1) 

Eye problems 1.4 (0.2) 1.0 (0.1) 

Skin problems 2.5 (0.5) 1.1 (0.1) 

Reproductive problems 

(e.g., infertility, dystocia) 1.1 (0.2) 0.6 (0.1) 

Behavioral problems (e.g., 

unusual, affects use or 

safety) 0.5 (0.1) 0.2 (0.0) 

Injury/wounds/trauma 6.2 (0.5) 4.7 (0.2) 

Lameness, leg, or hoof 

problems (could not be 

used for intended purpose 

without treatment)* 4.1 (0.4) 2.8 (0.2) 

Neurologic problems (e.g., 

spinal problem, wobblers, 

seizure, West Nile virus, 

EPM) 0.4 (0.1) 0.2 (0.0) 

Infectious disease 

unrelated to specific body 

system (septicemia, blood 

infections) 0.8 (0.2) 0.3 (0.1) 

Chronic weight loss 0.7 (0.2) 0.2 (0.0) 

Overweight/obese 0.9 (0.2) 0.9 (0.1) 

Liver or kidney disease N/A 0.1 (0.0) 

Cancer N/A 0.1 (0.0) 

Other N/A 0.3 (0.1) 

*Question from 1998 was worded as leg or hoof problems instead of lameness, leg, or hoof 

problems (2005). 

b. For operations that had any resident equids 6 months of age or older during

the previous 12 months, percentage of equids that became affected with the

following conditions:
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

50 / Equine 2005

8. Births

The percentage of operations that had any equine births on the operation during

the previous 12 months decreased from 42.2 percent in 1998 to 33.6 percent in

2005.

a. Percentage of operations that had any equine births on the operation during

the previous 12 months:

Percent Operations 

1998 2005 

Percent Std. Error Percent Std. Error 

42.2 (2.4) 33.6 (0.9) 

The percentages of foals born alive were similar in 1998 and 2005. Less than 8

percent of foals were born dead or aborted in 1998 and 2005.

b. Percentage of foals by birth outcome during the previous 12 months:

Percent Foals 

1998 2005 

Births Percent Std. Error Percent Std. Error 

Born alive 92.9 (1.0) 93.5 (0.5) 

Born dead or aborted* 7.1 (1.0) 6.5 (0.5) 

Total 100.0 100.0 

*Options in 1998 were born alive, born dead full term, and born dead premature. 
USDA APHIS VS / 51

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

9. Foal deaths

The overall percentages of foals aged 30 days or less that died were similar in

1998 and 2005, with between 4 and 5 percent of foals born alive dying in the first

30 days of life. The percentage of foals that died in the first 2 days was about the

same as the percentage of foals that died in the next 28 days.

a. For foals born alive, percentage of foals that died in the first 30 days of life

(including born on or moved onto the operation) during the previous 12 months,

by age at death (in days):

Percent Foals 

1998 2005 

Age at Death (Days) Percent Std. Error Percent Std. Error 

2 or less 2.0 (0.4) 2.6 (0.3) 

3 to 30 2.2 (0.6) 2.3 (0.3) 

Total 4.2 (0.8) 4.9 (0.4) 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

52 / Equine 2005

b. For foals born alive, percentage of foal deaths during the first 30 days of life,

by cause of death:

The percentages of foal deaths attributed to unknown and “other” causes

decreased from 1998 to 2005. Two potential causes of foal deaths were included

in the 2005 questionnaire but not the 1998 questionnaire: infectious disease

unrelated to specific body system/blood infection (septicemia), and failed to get

colostrum or milk from mare. Together, these two causes accounted for 18.2

percent of foal deaths in 2005. The percentage foal deaths from digestive

problems other than colic increased from 0.6 percent in 1998 to 6.4 percent in

2005. The leading causes of death in 2005—excluding unknown and “other”—

were injury/wounds/trauma, failed to get colostrum or milk from mare, dystocia,

and birth defects. In 1998, “other” reported known causes of foal death included

prematurity, lack of milk or colostrum production by mare, exposure, drowning,

and infection. In 2005 “other” known causes of foal death included predator

attacks and adverse environmental conditions.

Percent Foal Deaths 

1998 2005 

Cause of Death Percent Std. Error Percent Std. Error 

Colic 0.2 (0.1) 1.5 (1.2) 

Other digestive 

problems (e.g., 

diarrhea) 0.6 (0.3) 6.4 (1.9) 

Respiratory problems 

(e.g., pneumonia, 

strangles, Rhodococcus 

equi, etc.) 1.5 (0.7) 3.6 (1.3) 

Neurologic problems 

(e.g., spinal problem, 

wobblers, seizure, 

EPM, WNV, sleeping 

sickness, 

maladjustment 

syndrome) 3.1 (1.9) 0.5 (0.4) 

Dystocia, trauma, or 

complications at birth 5.1 (3.2) 10.7 (2.6) 

Birth defects 17.6 (6.4) 8.9 (2.1) 

Injury/wounds/trauma 

unrelated to birth 9.4 (7.7) 18.6 (3.3) 

Infectious disease 

unrelated to specific 

body system, blood 

infection (septicemia) N/A 3.3 (1.7) 

Failed to get colostrum 

or milk from mare N/A 14.9 (3.5) 

Other 29.3 (9.1) 13.7 (3.0) 

Unknown cause 33.2 (8.2) 17.9 (3.1) 

Total 100.0 100.0 
USDA APHIS VS / 53

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

10. Equid deaths

The overall mortality rates for resident equids more than 30 days of age were

similar in 1998 and 2005 (2.0 percent and 1.8 percent, respectively). The highest

mortality rates in both 1998 and 2005 occurred in equids 20 years of age or older

(approximately eight to nine times the rate for equids aged more than 30 days to

less than 20 years).

a. Percentage of resident equids more than 30 days of age that died or were

euthanized during the previous 12 months, by age:

Based on common “write-in” causes in 1998, several reasons for death were

added to the 2005 questionnaire, including cancer, liver/kidney problem, fire/

lightning or other storm, and poisoning/toxicity (suspected or confirmed). In 1998,

these causes were included in the “other” category. For equids aged more than

30 days to less than 6 months, the percentages of deaths were similar in 1998

and 2005 across all causes of death. About one in four deaths in resident equids

aged more than 30 days to less than 6 months were attributed to unknown

causes in 1998 and 2005. For equids aged 6 months or more, the percentages

of deaths were similar in 1998 and 2005 across all causes of death with the

exception of “other” causes of death, which was lower in 2005 than in 1998, likely

because of the additional choices added to the 2005 questionnaire. Commonly

reported causes of death in this age category in 1998 and 2005 were old age,

colic, and injury/wounds/trauma. “Other” known causes of death in 1998 included

cancer, heart disease, poisoning, lightning strike, liver disease, and birth defects.

In 2005, “other” known causes of death included heart attack, snake bite, stroke,

ruptured vessel, heat stroke, endocrine disease, and pigeon fever.

Percent Resident Equids* 

1998 2005 

Age at Death Percent Std. Error Percent Std. Error 

More than 30 days 

but less than 6 months 1.4 (0.5) 1.2 (0.2) 

6 months to less 

than 5 years 1.5 (0.5) 1.1 (0.1) 

5 years to less than 20 years 1.4 (0.3) 1.2 (0.1) 

20 years or older 11.9 (2.2) 10.2 (0.8) 

Total deaths of equids 

more than 30 days of age 2.0 (0.3) 1.8 (0.1) 

*(Number of resident equids that died or were euthanized) x 100/age class of resident equine 

inventory. 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

54 / Equine 2005

b. Percentage of equid deaths (including euthanasia), by cause of death and by

age:

Percent Equid Deaths 

Age Category 

More than 30 

Days to Less 

than 6 Months 

6 Months 

or Older 

1998 2005 1998 2005 

Cause Pct. 

Std. 

Error Pct. 

Std. 

Error Pct. 

Std. 

Error Pct. 

Std. 

Error 

Colic 7.5 (5.4) 3.4 (2.0) 22.2 (5.5) 15.2 (1.8) 

Other digestive 

problems (e.g., 

diarrhea) 9.3 (5.8) 8.3 (4.3) 1.3 (0.7) 3.0 (0.9) 

Respiratory

problems including 

strangles 2.8 (1.8) 7.3 (3.6) 3.1 (1.7) 2.7 (0.7) 

Neurologic 

problems (e.g., 

spinal problem, 

wobblers, seizure, 

WNV, EPM) 6.6 (5.0) 0.0 (--) 1.8 (1.5) 3.3 (0.8) 

Dystocia or birthing 

complications 0.1 (0.1) 0.0 (--) 1.3 (0.6) 2.3 (0.6) 

Reproductive 

problems other 

than dystocia 0.0 (--) 1.6 (1.6) 0.5 (0.3) 0.9 (0.4) 

Injury/wounds/ 

trauma 31.8 (14.3) 23.9 (7.9) 12.7 (5.8) 16.0 (1.7) 

Lameness, leg, or 

hoof problems 

(could not be used 

for intended 

purpose without 

treatment) 7.8 (7.6) 8.5 (3.5) 6.9 (3.5) 7.7 (1.3) 

Old age -- (--) N/A N/A 24.8 (5.8) 30.4 (2.4) 

Cancer N/A 0.0 (--) N/A 2.7 (0.7) 

Liver or 

kidney disease N/A 1.1 (1.1) N/A 1.9 (0.6) 

Fire, lightning 

strike, flood, or 

other storm N/A 7.9 (6.2) N/A 2.1 (0.9) 

Poisoning/toxicity 

(suspected or 

confirmed) N/A 0.0 (--) N/A 0.3 (0.2) 

Other known cause 5.8 (4.3) 14.6 (6.5) 18.0 (3.6) 5.8 (1.1) 

Unknown cause 28.3 (18.1) 23.4 (8.1) 7.4 (3.0) 5.7 (1.0) 

Total 100.0 100.0 100.0 100.0 
USDA APHIS VS / 55

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

C. Biosecurity 1. Nonresident equids

The percentages of operations with 0, 1 to 9, and 10 or more nonresident equids

that stayed fewer than 30 consecutive days were similar in 1998 and 2005.

Approximately 8 of 10 operations in 1998 and 2005 had no nonresident equid

visitors during the previous 12 months.

a. Percentage of operations by number of nonresident equids that stayed on the

operation for fewer than 30 consecutive days during the previous 12 months:

Percent Operations 

1998 2005 

Number 

Nonresident Equids Percent Std. Error Percent Std. Error 

0 79.1 (2.0) 81.0 (0.8) 

1 to 9 15.4 (1.7) 14.7 (0.7) 

10 or more 5.5 (1.3) 4.3 (0.4) 

Total 100.0 100.0 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

56 / Equine 2005

For operations that had nonresident equids that stayed for fewer than 30

consecutive days, the percentages of operations that implemented the following

health requirements for nonresident equids were similar in 1998 and 2005. In

2005, three choices were added to the health-requirement category: screening

test for strangles or history of no occurrence in past 6 months, other past

medical history, and quarantine prior to contact with resident equids. However, it

is unlikely that these additional choices altered the response to the other choices

because the choices for health requirements were not mutually exclusive (e.g.,

operations could have more than one of the requirements for nonresident

equids).

b. For operations with nonresident equids that stayed fewer than 30 consecutive

days during the previous 12 months, percentage of operations by frequency that

the following health requirements were always or sometimes implemented for the

majority of nonresident equids:

Percent Operations 

1998 2005 

Health Requirement Percent Std. Error Percent Std. Error 

Official health certificate, i.e., 

certified veterinary inspection (CVI) 31.9 (4.9) 24.8 (1.9) 

Veterinary examination 

other than CVI 30.7 (5.1) 18.4 (1.7) 

Coggins test 

(EIA test, swamp fever test) 50.2 (5.3) 45.3 (2.2) 

Vaccination within past year 43.5 (5.2) 36.3 (2.1) 

Deworming within past year 43.2 (5.2) 33.6 (2.1) 

Screening test for strangles 

or history of no occurrence 

in past 6 months N/A 9.7 (1.2) 

Other past medical 

history from owner N/A 21.8 (1.7) 

Quarantine prior to 

contact with resident equids N/A 17.2 (1.5) 

Other 10.6 (3.1) 3.8 (0.8) 
USDA APHIS VS / 57

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

2. Additions

The percentage of operations that added new resident equids and the

percentage of resident equids added both decreased from 1998 to 2005.

Operations with primary functions of farm/ranch and residences with equids for

personal use accounted for much of the difference, with a smaller percentage of

operations with these primary functions indicating addition of new residents in

2005 compared to 1998.

a. Percentage of operations that added new resident equids during the previous

12 months and percentage of equids added, including foals not born to a

resident mare (excluding births):

Percent 

1998 2005 

Measure Pct. Std. Error Pct. Std. Error 

Percent operations 40.5 (2.3) 21.5 (0.8) 

Percent resident equids* 11.3 (1.3) 6.3 (0.5) 

*Total number of equids added to resident equine population x 100/total resident equine inventory. 

The percentages of operations adding new resident equids from various

geographic sources were similar in 1998 and 2005. Less than 2 percent of

operations added equids from outside the United States in 1998 and 2005.

b. For operations that added new resident equids during the previous 12 months,

percentage of operations by source location of added equids:

 Percent Operations 

 1998 2005 

Source Percent Std. Error Percent Std. Error 

Within State 85.4 (2.4) 81.6 (1.6) 

Outside State, 

within United States 28.1 (3.3) 29.9 (1.9) 

Canada 1.2 (0.5) 1.1 (0.3) 

Mexico 0.0 (--) 0.2 (0.1) 

Outside North America 0.5 (0.3) 0.3 (0.1) 

Unknown location 0.2 (0.1) 1.0 (0.5) 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

58 / Equine 2005

The percentages of new additions by source location were similar in 1998 and

2005. The majority of new resident equids came from within the State in 1998

and 2005.

c. For operations that added new resident equids during the previous 12 months,

percentage of new additions by source location of added equids:

 Percent Additions* 

 1998 2005 

Source Percent Std. Error Percent Std. Error 

Within State 73.9 (4.0) 70.7 (3.2) 

Outside State, within 

United States 25.1 (3.9) 25.7 (3.0) 

Canada 0.5 (0.2) 2.2 (1.4) 

Mexico 0.0 (--) 0.5 (0.3) 

Outside North America 0.3 (0.1) 0.4 (0.3) 

Unknown location 0.2 (0.1) 0.5 (0.3) 

Total 100.0 100.0 

*Number of equids added to resident equine population from various sources x 100/total new 

additions from all sources. 
USDA APHIS VS / 59

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

Health requirements for newly added resident equids were not mutually

exclusive. For operations that added new resident equids during the previous 12

months, the percentage of operations that required an official health certificate

(CVI) for newly added resident equids decreased from 53.1 percent in 1998 to

34.6 percent in 2005. Likewise, the percentage of operations that required a

veterinary examination other than an official health certificate (CVI) for newly

added equids decreased from 45.1 percent in 1998 to 29.2 percent in 2005.

Three additional choices for health requirements were included in the 2005

questionnaire: screening test for strangles or history of no occurrence in past 6

months, other past medical history from owner, and quarantine prior to contact

with resident equids. However, since the health-requirement choices were not

mutually exclusive, it is unlikely that responses to the first five categories were

influenced by the new choices. The percentage of “other” requirements

decreased from 13.0 percent in 1998 to 5.0 percent in 2005, likely because of

the above-mentioned choices added to the 2005 questionnaire. The percentage

of operations with a primary function of equine boarding/training stable was

higher in 1998 compared to 2005 (10.0 percent and 5.9 percent, respectively).

The percentage of operations with a primary function of farm/ranch was lower in

1998 compared to 2005. Boarding/training facilities were more likely than farm/

ranch operations to require an official health certificate (CVI), EIA test, and

screening test for strangles or history of no occurrence in past 6 months.

d. For operations that added new resident equids during the previous12 months,

percentage of operations that always or sometimes implemented the following

health requirements for new additions:

 Percent Operations 

 1998 2005 

Health Requirement Percent 

Std. 

Error Percent 

Std. 

Error 

Official health certificate (CVI) 53.1 (3.5) 34.6 (2.0) 

Veterinary examination other than CVI 45.1 (3.7) 29.2 (1.9) 

Coggins test 

(EIA test, swamp fever test) 67.2 (3.7) 61.8 (2.0) 

Vaccination within past year 57.0 (3.6) 49.2 (2.1) 

Deworming within past year 65.8 (3.7) 48.9 (2.1) 

Screening test for strangles or history 

of no occurrence in past 6 months N/A 14.2 (1.4) 

Other past medical history from owner N/A 36.3 (2.0) 

Quarantine prior to contact 

with resident equids N/A 32.0 (2.0) 

Other 13.0 (2.5) 5.0 (0.9) 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

60 / Equine 2005

3. Contact with other animals

The percentage of operations where poultry had direct contact with resident

equids or their feed increased from 13.4 percent in 1998 to 18.6 percent in 2005.

The percentage of operations where cattle had direct contact with resident

equids or their feed increased from 34.1 percent in 1998 to 43.2 percent in 2005.

The increase in equid contact with cattle and poultry may be a result of the

higher percentage of operations with farm/ranch as a primary function in 2005

compared to 1998.

Percentage of operations where the following animals had physical contact with

resident equids or their feed:

Percent Operations 

1998 2005 

Animal Percent Std. Error Percent Std. Error 

Poultry 13.4 (1.5) 18.6 (0.8) 

Pigs 3.7 (0.8) 4.7 (0.4) 

Cattle 34.1 (2.3) 43.2 (1.0) 

Sheep/goats 11.4 (1.3) 13.9 (0.7) 

Llamas/alpacas 1.5 (0.5) 2.4 (0.3) 

Emus/ostriches 1.0 (0.3) 1.2 (0.2) 

Dogs 77.9 (1.9) 76.9 (0.9) 

Cats 67.7 (2.3) 66.4 (1.0) 
USDA APHIS VS / 61

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

D. Equid Movement 1. Distance traveled

The percentage of operations that did not move equids off the operation

increased from 19.3 percent in 1998 to 36.6 percent in 2005. Operations with a

primary function of farm/ranch and residences with equids for personal use

accounted for much of the difference, as these operations moved horses less

frequently in 2005 compared to 1998, and farm/ranch operations accounted for a

larger percentage of operations in 2005 than in 1998.

Percentage of operations by maximum one-way distance resident equids

traveled and returned during the previous 12 months (whether or not by vehicle,

farthest away animal got from home operation):

Percent Operations 

1998 2005 

Distance (Miles) Percent Std. Error Percent Std. Error 

0 19.3 (1.9) 36.6 (1.0) 

1 to 9 8.6 (1.7) 5.0 (0.5) 

10 to 49 20.5 (2.0) 19.0 (0.8) 

50 to 99 11.5 (1.4) 8.9 (0.6) 

100 to 499 27.4 (2.1) 22.2 (0.9) 

500 to 999 7.5 (1.4) 5.4 (0.4) 

1,000 or more 5.2 (0.9) 2.9 (0.3) 

Total 100.0 100.0 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

62 / Equine 2005

2. Vehicle transportation

The percentage of operations that transported any resident equids by vehicle off

the home operation and returned the equids during the previous 12 months

decreased from 73.5 percent in 1998 to 58.4 percent in 2005. Operations with a

primary function of farm/ranch and residences with equids for personal use

accounted for much of the difference, as these operations moved horses less

frequently in 2005 than in 1998, and farm/ranch operations accounted for a

larger percentage of operations in 2005 than in 1998.

Percentage of operations that transported any resident equids by vehicle off the

home operation for any purpose and returned the equids to the operation during

the previous 12 months:

Percent Operations 

1998 2005 

Percent Std. Error Percent Std. Error 

73.5 (2.3) 58.4 (1.0) 
USDA APHIS VS / 63

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

3. Destination

The destinations of transported equids were not mutually exclusive. For

example, an operation could have transported equids with a final destination

within the State for one trip and to Canada for another trip. Movement patterns

were similar in 1998 and 2005

For operations that transported resident equids by vehicle off the home operation

and returned during the previous 12 months, percentage of operations by

destination of equids:

4. Direct contact with outside equids during trips

The percentage of operations where resident equids left the home operation and

had direct contact with outside equids decreased from 87.3 percent in 1998 to

75.1 percent in 2005.

a. Percentage of operations that had resident equids that left the operation and

returned after direct contact with outside equids:

Percent Operations 

1998 2005 

Destination Percent Std. Error Percent Std. Error 

Within State 96.6 (1.2) 94.8 (0.6) 

Adjacent State 34.3 (1.2) 

Beyond adjacent States 

(including Alaska 

and Hawaii) 

30.8* (2.5) 

11.9 (0.8) 

Canada 1.3 (0.5) 0.7 (0.2) 

Mexico 0.0 (0.0) 0.3 (0.2) 

Outside North America 0.2 (0.1) 0.2 (0.1) 

*1998 questionnaire: outside State, within United States.

Percent Operations 

1998 2005 

Percent Std. Error Percent Std. Error 

87.3 (2.4) 75.1 (0.9) 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

64 / Equine 2005

For operations that had resident equids that left the home operation and returned

after direct contact with outside equids, the percentages of operations that

routinely isolated returning equids were similar in 1998 and 2005. The

percentage of operations that only isolated returning equids for a cause such as

disease or exposure to disease increased from 15.8 percent in 1998 to 26.0

percent in 2005. The percentage of operations that never isolated returning

equids decreased from 72.3 percent in 1998 to 60.6 percent in 2005.

b. For operations that had resident equids that left the home operation and

returned after direct contact with outside equids, percentage of operations by

infection-control practice used for returning equids:

Percent Operations 

1998* 2005 

Practice Percent Std. Error Percent Std. Error 

Routinely isolate 

returning equids 11.9 (2.5) 10.6 (0.7) 

Only isolate returning equids 

for a cause such as disease 

or exposure to disease 15.8 (2.4) 26.0 (1.0) 

Quarantine before arrival 

at home operation N/A 2.8 (0.4) 

Never isolate returning equids 72.3 (3.2) 60.6 (1.1) 

Total 100.0 100.0 

*Categories for 1998 were resident equine never leave premises, routinely isolated returning equine, 

isolated returning horses for a cause such as evidence of or exposure to disease, and never isolated 

returning horses. 
USDA APHIS VS / 65

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

E. General

Management

1. Feed source

The percentage of operations that fed grain concentrate/energy source beyond

hay or pasture during the previous 12 months was slightly higher in 1998 than in

2005 (95.9 percent and 90.1 percent, respectively).

a. Percentage of operations that fed grain concentrate/energy source (beyond

hay or pasture forage) during the previous 12 months:

Percent Operations 

1998 2005 

Percent Std. Error Percent Std. Error 

95.9 (1.1) 90.1 (0.6) 

For operations that fed grain concentrate/energy source during the previous 12

months, the reported percentage of grain/concentrate by source was averaged

over all operations. The highest percentage of grain/concentrate was purchased

in bags in both 1998 and 2005.

b. For operations that fed grain concentrate/energy source (beyond hay or

pasture forage) during the previous 12 months, operation average percentage of

grain/concentrate fed, by source:

Operation Average Percent of 

Grain/Concentrate 

1998 2005 

Source Percent Std. Error Percent Std. Error 

Purchased in 

bags (retail source) 82.5 (1.8) 79.1 (0.8) 

Bulk delivery 

from retail source 6.3 (1.1) 9.6 (0.6) 

Bulk delivery from 

nonretail source 3.4 (0.8) 3.0 (0.3) 

Home-grown 7.4 (1.2) 7.9 (0.5) 

Other 0.4 (0.2) 0.4 (0.1) 

Total 100.0 100.0 
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

66 / Equine 2005

The percentage of operations that stored grain/concentrate in a manner to

prevent fecal contamination by mice or rats increased from 77.6 percent in 1998

to 85.0 percent in 2005.

c. For operations that fed grain concentrate/energy source (beyond hay or

pasture forage) during the previous 12 months, percentage of operations that

stored grain/concentrate in a manner that prevents contamination by mice, rats,

or their feces:

Percent Operations 

1998* 2005 

Percent Std. Error Percent Std. Error 

77.6 (2.1) 85.0 (0.8) 

*Questionnaire in 1998 asked was feed stored in rodent-proof containers. 

2. Drinking water

The predominant sources of drinking water for equids were similar in 1998 and

2005, with well water being the predominant source of water for equids on over

half the operations in both 1998 and 2005.

Percentage of operations by predominant source of drinking water for resident

equids during the previous 12 months:

Percent Operations 

1998 2005 

Source Percent Std. Error Percent Std. Error 

Well 58.9 (2.5) 57.5 (0.9) 

Public/ 

municipal water supply 17.2 (2.3) 18.9 (0.8) 

Spring 5.2 (1.0) 5.4 (0.5) 

Surface water (pond, stream, 

river, or cistern) 18.2 (1.8) 18.1 (0.8) 

Other 0.5 (0.3) 0.1 (0.0) 

Total 100.0 100.0 

3. Insect control

The following methods of insect control were not mutually exclusive, as

operations could have used various combinations of insect control. The

percentage of operations that used repellant applied to equids decreased from

86.5 percent in 1998 to 73.1 percent in 2005. The percentages of operations that
USDA APHIS VS / 67

 Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

Percent Operations 

1998 2005 

Method Percent Std. Error Percent Std. Error 

Repellents applied to equids 86.5 (2.4) 73.1 (0.9) 

Insecticides applied in or 

near equine housing area 26.1 (3.2) 36.0 (1.0) 

Insecticides applied 

to pasture areas 1.2 (0.5) 5.5 (0.5) 

Regional control program, 

such as aerial spraying 2.5 (0.7) 4.1 (0.4) 

Sticky tape 26.7 (3.3) 20.9 (0.8) 

Bug zapper N/A 8.4 (0.6) 

Parasitic wasps specifically 

brought onto operation 2.4 (0.8) 3.1 (0.3) 

Face mask on equid 32.3 (3.7) 27.2 (0.9) 

Fly tags attached 

to equine halters 3.5 (1.4) 4.1 (0.4) 

Fly sheets on equid N/A 7.3 (0.5) 

Insect control product 

in feed, such as 

using Equitrol® 2.8 (1.0) 5.6 (0.5) 

Mosquito treatment 

in drinking water 

(mosquito dunks) N/A 6.3 (0.5) 

Water container emptied 

and refilled with fresh 

water at least weekly N/A 58.5 (1.0) 

Frequent removal of weeds 

and manure from premises N/A 51.3 (1.0) 

Screened-in stalls N/A 2.4 (0.3) 

Other 13.1 (2.4) 5.9 (0.5) 

Any method 91.3 (2.1) 88.9 (0.7) 

used insecticides applied in or near equine housing area and insecticide applied

on pastures increased from 1998 to 2005. Several methods of insect control

were added to the 2005 questionnaire: bug zapper, fly sheet on equids, mosquito

treatment in drinking water, water container emptied at least weekly, frequent

removal of manure and weeds from premises, and screened-in stalls, as they

were common “write-in” methods in the 1998 questionnaire. These additions

probably account for the decrease from 1998 to 2005 in the percentage of

operations that listed “other” as a method of insect control.

Percentage of operations where the following insect-control methods were used

during summer:
Section III: Management and Health Changes in the U.S. Equine Industry, 1998-2005

68 / Equine 2005

4. Manure management

Methods of disposing of manure and waste bedding were not mutually exclusive.

The percentage of operations that sold or gave away manure decreased from

24.9 percent in 1998 to 16.9 percent in 2005.

Percentage of operations by method of manure (including composted manure)

and/or waste bedding disposal used during the previous 12 months:

Percent Operations 

1998 2005 

Method Percent Std. Error Percent Std. Error 

Routine garbage pickup 1.7 (0.7) 2.6 (0.3) 

Hauled to landfill 

(not routine garbage pickup) 0.7 (0.3) 1.5 (0.2) 

Hauled away, 

other than to landfill 9.0 (1.2) 10.9 (0.6) 

Applied on fields on 

the operation where 

any livestock 

(including equids) graze 39.6 (2.6) 37.2 (1.0) 

Applied on fields on 

the operation where 

no livestock graze 40.9 (2.4) 42.0 (0.9) 

Manure/waste bedding 

allowed to accumulate 

or left to nature 31.6 (2.1) 32.4 (1.0) 

Sold or gave away 24.9 (2.1) 16.9 (0.7) 

Other 5.0 (1.1) 2.3 (0.3) 
USDA APHIS VS / 69

 Appendix I: Study Objectives and Related Outputs

1. Focus on health practices that could impact the occurrence of equine

infectious diseases.

• Part I: Baseline Reference of Equine Health and Management, 2005,

 November 2006

• Highlights of Equine 2005 Part I information sheet, November 2006

• Equine Identification and Familiarity with the National Identification System

 information sheet, November 2006

• Nonambulatory Equids in the United States information sheet, November

 2006

2. Determine health-management factors related to the control of equine

infectious diseases, as implemented on-farm in the 28 participating States.

• Equine Biosecurity and Biocontainment Practices on U.S. Equine Operations

information sheet, November 2006

3. Compare relevant data collected in 2005 to data collected during the NAHMS

Equine ’98 study.

• Part II: Changes in the U.S. Equine Industry, 1998-2005, February 2007

• Information sheets, expected winter 2007

4. Help identify trends in equine health management related to the control of

equine infectious diseases.

• Part II: Changes in the U.S. Equine Industry, 1998-2005, February 2007

• Information sheets, expected winter 2007

5. Gather data specific to equine vaccination.

• Part I: Baseline Reference of Equine Health and Management, 2005,

November 2006

• Vaccination Practices on U.S. Equine Operations information sheet, December

2006

Appendix: Study Objectives and Related Outputs