United States Department of Agriculture • Animal and Plant Health Inspection Service • Safeguarding American Agriculture 

Veterinary Services

Centers for Epidemiology and Animal Health May 2011 

_________________________________________________________________________________________________________________________ 

Clostridium difficile on U.S. Beef 

Cow-calf Operations 

Disease caused by Clostridium difficile is linked most 

commonly to nosocomial (hospital-acquired) infections in 

humans, especially after antibiotics are administered that 

alter normal gastrointestinal flora. Humans develop a 

spectrum of disease when infected with some strains of 

C. difficile. Symptoms range from mild diarrhea to lifethreatening toxic megacolon and pseudo-membranous 

colitis (Weese, 2010). Even though C. difficile is typically 

seen as a nosocomial infection, there are increasing 

reports of community acquired infections. 

C. difficile is a spore-forming organism which can survive 

in the environment for long periods and can be ingested 

by animals or humans through contaminated foodstuffs 

and water (Yaeger et al., 2002). C. difficile has also been 

associated with clinical disease in young pigs and dairy 

calves (Yaeger et al., 2002; Hammitt et al., 2008). 

Shedding of C. difficile bacteria in animal feces can 

occur in the absence of clinical signs (Weese, 2010). In 

addition, some strains of C. difficile have been isolated 

from ground beef, ground pork, and ground veal 

purchased from retail markets in Canada which could 

serve as a source of infection in humans (RodriguezPalacios et al., 2007; Weese et al., 2009). To date, there 

has been little information available on the distribution 

and characteristics of C. difficile on various types of 

livestock operations across the United States. 

Beef 2007–08 study 

The U.S. Department of Agriculture’s National 

Animal Health Monitoring System (NAHMS) conducted 

the Beef 2007–08 study, which focused on beef cow-calf 

health and management practices in 24 States.1

 These 

States represented 79.6 percent of U.S. operations with 

beef cows and 87.8 percent of U.S. beef cows. One 

objective of the Beef 2007–08 study was to determine if 

C. difficile could be found in the feces of beef cows on 

U.S. cow-calf operations in the United States and, if so, 

to determine the characteristics of the C. difficile

isolates. 

 

1 States/Regions: 

West: California, Colorado, Idaho, Montana, New Mexico, Oregon, 

Wyoming 

Central: Iowa, Kansas, Missouri, Nebraska, North Dakota, South 

Dakota 

Southeast: Alabama, Arkansas, Florida, Georgia, Kentucky, 

Louisiana, Mississippi, Oklahoma, Tennessee, Texas, Virginia 

C. difficile prevalence 

 During the Beef 2007–08 study, testing for C. difficile

was performed on 173 cow-calf operations across the 24 

participating States. 

Overall, 2,965 fecal samples from beef cows 

presumed to be healthy were cultured for the presence 

of C. difficile.2 Of the 2,965 fecal samples tested, 

C. difficile was isolated from 188 (6.3 percent) [table 1]. 

At least 1 positive sample was found on 76 of the 173 

operations tested for C. difficile (43.9 percent). 

Table 1. Number and percentage of samples and 

operations tested for C. difficile, by test result 

Samples 

Tested 

Operations 

Tested 

Test 

Result No. Pct. No. Pct. 

Positive 188 6.3 76 43.9 

Negative 2,777 93.7 97 56.1 

Total 2,965 100.0 173 100.0 

 

2

 Culture methods available in Thitaram et al. (2011). 

Technical Brief
United States Department of Agriculture • Animal and Plant Health Inspection Service • Safeguarding American Agriculture 

Sample-level results 

Herd size and region

 There was no difference by herd size in the 

percentage of samples positive for C. difficile (p=0.23) 

[table 2]. 

Table 2. Number of samples tested and number and 

percentage of samples positive for C. difficile, by 

herd size 

Herd Size (number of beef cows) 

1–49 50–99 

100–

199 

200 or 

More Total 

Number 

samples 

tested 

570 475 794 1,126 2,965 

Number 

samples 

positive 

44 32 65 47 188 

Percent 

samples 

positive 

7.7 6.7 8.2 4.2 6.3 

 There was a difference in the percentage of samples 

positive for C. difficile by region (p=0.009), with a higher 

percentage of positive samples observed from the 

Southeast region than from the West or Central regions 

(table 3). 

Table 3. Number of samples tested and number and 

percentage of samples positive for C. difficile, by 

region 

 Region 

 West Central Southeast 

Number 

samples 

tested 

669 990 1,306 

Number 

samples 

positive 

17 43 128 

Percent 

samples 

positive 

2.5 4.3 9.8 

Operation-level results

Herd size and region

 There was no significant difference by herd size 

(p=0.50) in the percentage of operations positive for 

C. difficile-positive [table 4]. 

Table 4. Number of operations tested and number 

and percentage of operations with at least one 

sample positive for C. difficile, by herd size 

Herd Size (number of beef cows) 

1–49 50–99 

100–

199 

200 or 

More Total 

Number 

operations 

tested 

49 26 42 56 173 

Number 

operations 

positive 

26 11 17 22 76 

Percent 

operations 

positive 

53.1 42.3 40.5 39.3 43.9 

While the highest percentage of operations positive 

for C. difficile was in the Southeast region, the 

differences between regions were not statistically 

significant (p=0.15) [table 5]. 

Table 5. Number of operations tested and number 

and percentage of operations with at least one 

sample positive for C. difficile, by region 

 Region 

 West Central Southeast 

Number 

operations 

tested 

39 54 80 

Number 

operations 

positive 

11 21 44 

Percent 

operations 

positive 

28.2 38.9 55.0 
United States Department of Agriculture • Animal and Plant Health Inspection Service • Safeguarding American Agriculture 

Summary

 Overall, the prevalence of C. difficile was relatively 

low (6.3 percent of samples positive) but the organism 

was widely distributed (43.9 percent of operations had at 

least one positive sample). 

The recovery of C. difficile from feces on livestock 

operations warrants further investigation. Not all strains 

of C. difficile appear to have the same propensity to 

cause disease. Therefore, isolates from this study will be 

further characterized to determine how related these 

isolates are to those causing human disease. Further 

characterization of C. difficile isolates, including 

molecular typing and additional epidemiological studies, 

is needed to ascertain if a relationship exists between 

food animal isolates and those from humans in order to 

determine the potential for foodborne disease. 

References

Hammitt MC, Bueschel DM, Keel MK, Glock RD, Cuneo 

P, DeYoung DW, Reggiardo C, Trinh HT, Songer 

JG. 2008. A possible role for Clostridium difficile in 

the etiology of calf enteritis. Vet Microbiol.127(3–

4):343–352. 

Rodriguez-Palacios A, Staempfli HR, Duffield T, Weese 

JS. 2007. Clostridium difficile in retail ground meat, 

Canada. Emerg Infect Dis.13(3):485–487. 

Thitaram SN, Frank JF, Lyon SA, Siragusa GR, Bailey 

JS, Lombard JE, Haley CA, Wagner BA, Dargatz 

DA, Fedorka-Cray PJ. 2011. Clostridium difficile

from healthy food animals: optimized isolation and 

prevalence. J Food Prot 74(1):130–133. 

Weese JS. 2010. Clostridium difficile in food—innocent 

bystander or serious treat? Clin Microbiol Infect 16: 

3–10. 

Weese JS, Avery BP, Rousseau J, Reid-Smith RJ. 2009. 

Detection and enumeration of Clostridium difficile

spores in retail beef and pork. Appl Environ 

Microbiol 75(15):5009–5011. 

Yaeger M, Funk N, Hoffman L. 2002. A survey of agents 

associated with neonatal diarrhea in Iowa swine 

including Clostridium difficile and porcine 

reproductive and respiratory syndrome virus. J Vet 

Diagn Invest 14(4):281–287. 

AHPIS acknowledges the contributions of the USDAARS Bacterial Epidemiology and Antimicrobial 

Resistance Research Unit for their participation in the 

Beef 2007-08 study. 

____________________ 

For more information, contact: 

USDA–APHIS–VS–CEAH 

NRRC Building B, M.S. 2E7 

2150 Centre Avenue 

Fort Collins, CO 80526-8117 

970.494.7000 

Email: NAHMS@aphis.usda.gov 

http://nahms.aphis.usda.gov 

#598.0511 

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