[Federal Register Volume 69, Number 213 (Thursday, November 4, 2004)]
[Rules and Regulations]
[Pages 64245-64249]
From the Federal Register Online via the Government Publishing Office [www.gpo.gov]
[FR Doc No: 04-24646]



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Rules and Regulations
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Federal Register / Vol. 69, No. 213 / Thursday, November 4, 2004 / 
Rules and Regulations

[[Page 64245]]



DEPARTMENT OF AGRICULTURE

Animal and Plant Health Inspection Service

9 CFR Part 78

[Docket No. 02-070-3]


Official Brucellosis Tests

AGENCY: Animal and Plant Health Inspection Service, USDA.

ACTION: Final rule.

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SUMMARY: We are amending the regulations by adding the fluorescence 
polarization assay to the lists of confirmatory and official tests for 
determining the brucellosis disease status of test-eligible cattle, 
bison, and swine. This action is warranted because the fluorescence 
polarization assay has been shown to provide an efficient, accurate, 
automated, and cost-effective means of determining the brucellosis 
status of test eligible cattle, bison, and swine. Adding the 
fluorescence polarization assay to the lists of confirmatory and 
official tests for brucellosis in cattle, bison, and swine will help to 
prevent the spread of brucellosis by making available an additional 
tool for its diagnosis in those animals.

DATES: Effective December 6, 2004.

FOR FURTHER INFORMATION CONTACT: Dr. Arnold Gertonson, National Center 
for Animal Health Programs, VS, APHIS, 2150 Centre Avenue, Bldg. B. MSC 
3E20, Fort Collins, CO 80526-8117; (970) 494-7363.

SUPPLEMENTARY INFORMATION:

Background

    Brucellosis is a contagious disease affecting animals and humans, 
caused by bacteria of the genus Brucella. In its principal animal 
hosts--cattle, bison, and swine--brucellosis is characterized by 
abortion and impaired fertility. The regulations in 9 CFR part 78 
govern the interstate movement of cattle, bison, and swine in order to 
help prevent the spread of brucellosis.
    On May 6, 2004, we published in the Federal Register (69 FR 25338-
25340, Docket No. 02-070-1) a proposal to amend the regulations by 
adding the fluorescence polarization (FP) assay to the list of official 
tests for determining the brucellosis disease status of test-eligible 
cattle, bison, and swine. In our proposed rule, we made available a 
complete report of field trial and testing results for validation of 
the FP assay in cattle, bison, and swine; that information may be 
viewed on the Internet at http://www.aphis.usda.gov/vs/nahps/brucellosis/ or obtained from the person listed under FOR FURTHER 
INFORMATION CONTACT.
    We solicited comments concerning our proposal for 60 days ending 
June 21, 2004. We subsequently reopened the comment period until July 
21, 2004, in a document published in the Federal Register on July 6, 
2004 (69 FR 40556, Docket No. 02-070-2). We received nine comments by 
that date. The comments were from researchers, test equipment 
manufacturers, representatives of State governments, animal welfare 
organizations, and private citizens. They are discussed below by topic.
    Some commenters stated that the Animal and Plant Health Inspection 
Service's (APHIS's) intentions regarding testing on wild bison were 
unclear in the proposed rule and that a statement should be added in 
the final rule clarifying that we do not intend to use the FP assay on 
wild bison. The commenters requested that APHIS provide additional 
information, including an additional disclosure of all FP assay 
validation data for bison, an analysis of FP assay data from 
Yellowstone National Park bison sampled in the winter of 2002-2003, and 
a description of the specific FP assay procedures that would be used on 
Yellowstone bison. The commenters stated that even if APHIS were to 
provide this additional information to their satisfaction, APHIS would 
need to prove that it had legal authority over wild bison. The 
commenters admitted that while ``animal,'' as defined by the Animal 
Health Protection Act (AHPA), includes wild animals, the Act limits 
APHIS's authority to domestic livestock and other animals that are 
under human control. The commenters contended that the FP assay cannot 
be applied to wild animals because their movements are not associated 
with interstate trade or importation. The commenters added that the 
only circumstances in which APHIS would have control over wildlife is 
if the Secretary determines that an extraordinary emergency exists 
because of the presence in the United States of a pest or disease that 
threatens U.S. livestock. The commenters note that the Secretary has 
not done so for brucellosis to date.
    With respect to the commenters' request for additional information, 
we note that the data and analyses sought by the commenters are 
summarized in the report we made available with the proposed rule. As 
noted earlier in this document, the report may be viewed on the 
Internet at http://www.aphis.usda.gov/vs/nahps/brucellosis/ and may be 
obtained from the person listed under FOR FURTHER INFORMATION CONTACT. 
We believe the data provided is adequate to support our addition of the 
FP assay to the list of official and confirmatory tests for 
brucellosis. The commenters have been informed in the past that they 
may request the specific data they are seeking from its source (i.e., 
the Montana Veterinary Diagnostic Lab).
    We do not agree with the commenters' characterization of APHIS's 
authority under the AHPA. For example, the AHPA gives APHIS broad 
authority ``to carry out operations and measures to detect, control, or 
eradicate any pest or disease of livestock (including the drawing of 
blood and diagnostic testing of animals)'' (7 U.S.C. 8308). This 
provision clearly includes testing of wild animals if it is determined 
that such animals pose a threat of spreading disease to U.S. livestock. 
As the commenter noted, the term ``animal'' is defined to include any 
member of the animal kingdom. In the past wild bison and elk have been 
identified as the source of brucellosis infection in domestic 
livestock, and we will test such animals when we believe it is 
necessary to prevent the further spread of brucellosis in livestock.
    One commenter suggested that we amend our proposed changes to the 
definition of official test in Sec.  78.1 to describe the circumstances 
under which the FP assay would be approved as a stand alone test.

[[Page 64246]]

    We are approving the FP assay as an official test, meaning it can 
be carried out whenever it is considered necessary to test cattle, 
bison, and swine for brucellosis. We agree with this commenter that the 
FP assay is also recognized as a confirmatory test, but rather than 
amending paragraph (a)(13) of the definition of official test as the 
commenter suggested, we have amended the definition of confirmatory 
test in Sec.  78.1 in this final rule by adding the FP assay to the 
list of confirmatory tests. This change will allow for the FP assay to 
be used as a stand alone test or in combination with other serologic 
tests. In addition, because the FP assay's performance characteristics 
compare favorably to the complement-fixation test (CFT), and because 
the CFT is already recognized by APHIS as a confirmatory test, the FP 
assay is also considered a reliable confirmatory test for brucellosis. 
Nevertheless, the decision as to which diagnostic tests to use depends 
on the situation and the State where the testing is done. Ultimately, 
the standard serologic protocol used in each Federal/State cooperative 
brucellosis laboratory depends on the laboratory's cooperative 
agreement.
    Some commenters stated that APHIS and/or other agencies involved in 
Yellowstone bison management must first evaluate the potential impacts 
of the FP assay on bison in the Greater Yellowstone Area before using 
the test on wild bison. They requested an environmental assessment be 
conducted evaluating potential environmental effects on using the test 
on wild bison in the Yellowstone area.
    We have determined that an environmental assessment is not needed 
in connection with our addition of the FP assay to the lists of 
official and confirmatory tests. With respect to bison, by adding the 
FP assay to the lists of official and confirmatory tests, we are merely 
saying that it is a tool that can be used for test-eligible bison (with 
no distinction between domestic and wild bison) without requiring its 
use. The record of decision (ROD) for the environmental impact 
statement (EIS) prepared for the Bison Management Plan \1\ contemplates 
the use of more efficient and effective tests as they become available. 
It will result in a more effective means of identifying animals that 
are likely carriers of brucellosis. By using the FP assay, we will be 
making the program more effective.
---------------------------------------------------------------------------

    \1\ The ROD can be found at http://www.planning.nps.gov/document/yellbisonrod.pdf.
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    Some commenters requested proof that the test's validation process 
is consistent with Office of International Epizooties (OIE) standards. 
The commenters contended that APHIS did not follow the appropriate 
process, as set by OIE, in validating the FP assay, which includes 
conducting an estimate of the disease prevalence in the specific 
population and ensuring that diagnostic sensitivity and specificity 
estimates are as accurate as possible.
    We believe that the FP assay validation process was consistent with 
OIE standards. In fact, the FP assay is recognized by OIE as one of 
four serologic tests recommended for use in diagnosing bovine 
brucellosis. According to OIE's Manual of Diagnostic Tests and Vaccines 
for Terrestrial Animals, ``The diagnostic performance characteristics 
of some enzyme-linked immunosorbent assays (ELISAs) and the 
fluorescence polarisation assay (FPA) are comparable with or better 
than that of the CFT, and as they are technically simpler to perform 
and more robust, their use may be preferred.'' In addition, the manual 
recognizes the FP Assay as a screening and/or confirmatory test for 
brucellosis in swine.
    Evidence has previously been presented in the FP assay validation 
report regarding the performance of the FP assay among cattle, bison, 
and swine populations in several countries, including Canada and the 
United States. OIE's Manual of Diagnostic Tests and Vaccines for 
Terrestrial Animals states that B. abortus infection follows a similar 
course in buffaloes (Bubalus bubalus), bison (Bison bison), yak (Bos 
grunniens), elk (Cerves canadensis), camels (Camelus bactrianus and C. 
dromedarius), and cattle. The manual adds that the same serological 
procedures may be used for these species, but each test should be 
validated in the species under study. Given this criterion, the 
evidence presented in the report sufficiently establishes the validity 
of the FP assay for brucellosis in cattle, bison, and swine. 
Furthermore, the criterion does not suggest that a separate validation 
is necessary for wild populations of bison.
    Some commenters stated that the FP assay suffers from the same flaw 
that other brucellosis tests do in that it can only detect exposure, 
not infection. The commenters stated that no research was done 
regarding the potential for cross-reactive antibodies in wild bison 
that might result in false-positive results and contended that the use 
of this test on wild bison will lead to the additional slaughter of 
bison that were only exposed but not infected.
    Research shows the FP assay to be highly accurate, easily 
performed, and more effective than other brucellosis tests. We believe 
this will lead to animals being more accurately diagnosed and prevent 
the unnecessary slaughter of uninfected bison.
    The FP assay validation report contained data showing the FP assay, 
in one study, to have 100 percent sensitivity. Some commenters took 
issue with this conclusion. The commenters noted that some data in the 
report indicated that a large number of serologically positive animals 
were later found to have been slaughtered unnecessarily because they 
were culture-negative and therefore not infected.
    The commenters are incorrect in their calculations of sensitivity. 
Sensitivity is determined by calculating the proportion of infected 
animals that are positive to the test under consideration. One hundred 
percent of the animals that were culture-positive were positive to the 
FP assay, for a sensitivity of 100 percent. And 100 percent of the 
animals that were serologically positive to other tests were positive 
to the FP assay, again a sensitivity of 100 percent. Nevertheless, 
these results are from one study of the FP assay's performance. Another 
study cited in our technical report found the FP assay to have a 92 
percent sensitivity (Gall 2000). It is not expected that any serologic 
test is truly 100 percent sensitive, but in comparison with other 
serologic brucellosis assays, the studies show that the FP assay has 
consistently high sensitivity. As stated in our response to the 
previous comment, we believe the accuracy, ease of use, and 
effectiveness of the FP assay will lead to more accurate diagnoses of 
brucellosis and prevent the unnecessary slaughter of uninfected 
animals.
    Two commenters took issue with the description of the testing 
procedure we provided in the proposed rule's supplementary information 
section. The commenters stated that we described an indirect binding or 
competitive binding assay, but the FP assay is actually a direct 
binding assay. Both commenters recommended we describe the procedure as 
follows:

    The brucellosis FP diagnostic assay is a direct binding assay 
that uses fluorescence polarization technology to determine the 
presence of Brucella abortus antibody in serum indicating current or 
previous infection. The diagnostic test uses as its conjugate a 
fluorescent antigen that is composed of the O-polysaccharide (OPS) 
extracted from Brucella abortus cells and labeled with fluorescein. 
A fluorescence polarization instrument is used to measure the 
polarization state of the OPS conjugate.

[[Page 64247]]

A quantitative score indicates the presence of the antibody or no 
presence of the antibody.
    The technician performs the test as follows. A specific quantity 
of a sample of animal serum is added to a glass test tube or 
microtitre plate well containing a specified amount of buffer 
solution. The fluorescence polarization measurement instrument is 
used to determine the natural fluorescence of the sample in the 
buffer solution. Then, the technician adds a specific quantity of 
fluorescent conjugate antigen. And then the fluorescence 
polarization instrument measures the change in fluorescence 
polarization of the conjugate which indicates if the antibody is 
present in the sample.

    We agree that the text suggested by the commenters clarifies the FP 
assay's binding type. However, because the paragraphs pointed out by 
the commenters appeared only in the proposed rule's supplementary 
information section, it is not necessary to make any changes in the 
regulatory text of this final rule in response to the comments.
    One commenter suggested that we retain the provisions that were 
found in paragraph (a)(13) of the definition of official test in Sec.  
78.1 regarding the authority of the designated epidemiologist in each 
State to act on his/her best judgment when making diagnoses of 
brucellosis based on an assessment of all relevant information. In 
addition, the commenter recommended adding the same statement with 
respect to swine in the definition of official test be consistent with 
the provisions concerning cattle and bison.
    It appears that the commenter misunderstood; we did not propose to 
remove the text of paragraph (a)(13) in the definition of official test 
from the current regulations, but instead to redesignate the paragraph 
as (a)(14). With respect to the commenter's suggestion that we add a 
similar statement regarding the role of designated epidemiologists in 
making diagnoses of brucellosis in swine, we agree with the commenter 
and have added such a statement in this final rule as a new paragraph 
(b)(6) in the definition of official test.
    Some commenters stated that while the assay interpretation for 
swine is the same as that for bison and cattle, the FP assay for swine 
uses 40 microliters of sample instead of the 10 microliters of sample 
used for cattle and bison. For suspect swine samples, the test is 
repeated using a 40-microliter sample, whereas the sample size is 
doubled (to 20 microliters) when repeating the test for suspect cattle 
and bison samples.
    We agree with these commenters and have changed all references to 
sample amounts to 40 microliters in paragraph (b)(5) of the definition 
of official test. In addition, we have added sentences to paragraphs 
(a)(13) and (b)(5) of that definition to explain that 10 microliters 
and 40 microliters, respectively, of sample are used in the initial 
testing.
    The supplementary information of our proposal described a test tube 
being used to perform the FP assay. Two commenters noted that the FP 
assay can be conducted in either a test tube or a microtiter plate 
format.
    We agree with these commenters and acknowledge so in this final 
rule. However, this information appeared in the background information 
of the proposed rule and did not appear in the text of the proposed 
regulations.
    One commenter suggested adding a sentence to the background 
information stating that FP assay technology has been developed for 
numerous human applications.
    We believe it is unnecessary to describe human applications of FP 
assay technology in this rule concerning brucellosis in cattle, bison, 
and swine.
    One commenter stated that the concentration immunoassay technology 
(CITE<SUP>[reg]</SUP>) test is no longer being manufactured and 
references to it should be removed and the FP assay should be put in 
their place.
    We are not removing the CITE<SUP>[reg]</SUP> test at this time 
because while it may no longer be manufactured, it is possible that it 
will be available sometime in the future. Rather than undergo the 
process of adding it to the regulations again, we will leave it on the 
list of official tests.
    One commenter suggested adding the following sentence to the 
economic analysis's discussion of the price of the FP assay: ``A 
smaller test kit size is being planned. High volume purchases are 
expected to have pricing discounts.''
    We have added a statement to the economic analysis indicating the 
possibility of smaller kits in the future and the possible effects on 
test kit prices. The addition of this statement has no effect on the 
conclusions of our economic analysis, however.
    One commenter stated that cattle should be kept out of areas where 
bison live. The commenter added that we should perform brucellosis 
tests on all cattle within 20 miles of bison. The commenter also 
suggested that all cattle movement between States stop.
    We do not believe that such extreme steps are warranted or 
necessary to prevent the spread of brucellosis in the United States.
    Therefore, for the reasons given in the proposed rule and in this 
document, we are adopting the proposed rule as a final rule, with the 
changes discussed in this document.

Executive Order 12866 and Regulatory Flexibility Act

    This rule has been reviewed under Executive Order 12866. For this 
action, the Office of Management and Budget has waived its review under 
Executive Order 12866.
    We are amending the regulations by adding the FP assay to the lists 
of confirmatory and official tests for determining the brucellosis 
disease status of test-eligible cattle, bison, and swine. This action 
is warranted because the FP assay has been shown to provide an 
efficient, accurate, automated, and cost-effective means of determining 
the brucellosis status of test eligible cattle, bison, and swine. 
Adding the FP assay to the lists of confirmatory and official tests for 
brucellosis in cattle, bison, and swine will help to prevent the spread 
of brucellosis by making available an additional tool for its diagnosis 
in those animals.
    This new test will help to prevent the spread of brucellosis by 
identifying infected cattle, bison, and swine. Preventing the spread of 
brucellosis is critical because of its potentially costly consequences 
for U.S. herd owners and consumers. In 1952, when brucellosis was 
widespread throughout the United States, annual losses from lowered 
milk production, aborted calves and pigs, and reduced breeding 
efficiency were estimated to total more than $400 million. Since then, 
eradication efforts have reduced annual losses due to brucellosis to 
less than $1 million. However, studies have shown that if eradication 
efforts were stopped, the cost of producing beef and milk would 
increase by an estimated $80 million annually in less than 10 years.
    While the test will provide long-term benefits by identifying 
animals infected with brucellosis, herd owners with animals that are 
found to be positive as a result of the FP assay, or any other official 
test, may experience some negative consequences. Once an infected herd 
is identified, the infection is contained by quarantining all infected 
animals and limiting their movement to slaughter only, until the 
disease can be eliminated from the herd. Quarantines affect the current 
income of herd owners, and depopulation affects their future income. 
Depopulation costs are mitigated by the sale of affected animals for 
slaughter and indemnity payments, but, in many cases, indemnification 
provides only partial compensation.
    However, there is no basis to conclude that the addition of the FP 
assay as an official and confirmatory test for brucellosis will result 
in more positive finds in privately owned herds

[[Page 64248]]

than another official or confirmatory test might indicate. Although 
research indicates that the FP assay can be a more accurate test, 
improved accuracy does not necessarily mean more positive finds; 
instead, the FP assay may yield fewer false positives than other tests, 
simply because it is more accurate.
    We do not expect that adding the FP assay to the lists of official 
and confirmatory tests for brucellosis will affect the market price of 
animals tested. Although more rapid testing may allow faster marketing, 
the effect on herd owners is not expected to be significant.
    The Regulatory Flexibility Act requires that agencies consider the 
economic impact of rule changes on small businesses, organizations, and 
governmental jurisdictions. We expect that the entities that will be 
affected by the addition of the FP assay to the lists of official and 
confirmatory tests will be herd owners, test reagent and equipment 
producers, livestock markets, shows, and exhibitions, and livestock 
buyers and sellers. It is anticipated that affected entities will be 
positively affected because the use of this test should provide greater 
assurance of the brucellosis status of the animals tested.
    Affected herd owners are likely to be small in size (when judged by 
the U.S. Small Business Administration's (SBA) standards). This 
determination is based on composite data for providers of the same and 
similar services. The latest Census data show that, in 2002, there were 
736,968 farms in the United States primarily engaged in beef cattle 
ranching and farming and dairy cattle and milk production. In 2002, 98 
percent of those farms had sales of less than $500,000, which is well 
below the SBA's small entity threshold of $750,000 for farms in that 
category. Similarly, in 2002, there were 33,655 U.S. farms primarily 
engaged in raising hogs and pigs. Of those farms, 81 percent had sales 
that year of less than $500,000, which is well below the SBA's small 
entity threshold of $750,000 for farms in that category. Additionally, 
in 2002, there were 41,238 farms listed under North American Industry 
Classification System code 11299, the classification category that 
includes farms primarily engaged in bison farming. The per-farm average 
sales for those 41,238 farms in 2002 was $39,868, which is well below 
the SBA's small entity threshold of $750,000 for farms in that 
category. Accordingly, most herd owners potentially affected by this 
rule will be small entities.
    The test will be performed at Federal/State cooperative brucellosis 
laboratories. Depending upon the Federal/State brucellosis cooperative 
agreement, APHIS may supply the reagents and equipment for performing 
this test. If APHIS supplies the reagents and equipment, it is 
anticipated that the test cost to the livestock producer will be the 
same as for the other brucellosis test options.
    Currently, the reagents are sold in two kit sizes, a 1,000-test kit 
($1.00/test) and a 10,000-test kit ($0.50/test). The costs to the 
laboratory to perform the test will vary, depending upon the number of 
tests performed. The test kit manufacturer has indicated that a smaller 
test kit size is being planned and that high volume purchases are 
expected to have pricing discounts. However, we currently have no 
information indicating what those discounts may be.
    A consideration that may affect the livestock producer is whether 
the test is performed by a federally accredited veterinarian at a 
livestock market. If the market inspecting veterinarian uses the test, 
the cost may vary depending upon the agreement the veterinarian has 
with the State to perform brucellosis testing at the market.
    It is anticipated that the test reagent and equipment producers 
will benefit from increased sales due to increased usage of the test. 
With increased usage of the test, the cost of the reagents and 
equipment should decline over time.
    Under these circumstances, the Administrator of the Animal and 
Plant Health Inspection Service has determined that this action will 
not have a significant economic impact on a substantial number of small 
entities.

Executive Order 12372

    This program/activity is listed in the Catalog of Federal Domestic 
Assistance under No. 10.025 and is subject to Executive Order 12372, 
which requires intergovernmental consultation with State and local 
officials. (See 7 CFR part 3015, subpart V.)

Executive Order 12988

    This final rule has been reviewed under Executive Order 12988, 
Civil Justice Reform. This rule: (1) Preempts all State and local laws 
and regulations that are in conflict with this rule; (2) has no 
retroactive effect; and (3) does not require administrative proceedings 
before parties may file suit in court challenging this rule.

Paperwork Reduction Act

    This final rule contains no new information collection or 
recordkeeping requirements under the Paperwork Reduction Act of 1995 
(44 U.S.C. 3501 et seq.).

List of Subjects in 9 CFR Part 78

    Animal diseases, Bison, Cattle, Hogs, Quarantine, Reporting and 
recordkeeping requirements, Transportation.


0
Accordingly, we are amending 9 CFR part 78 as follows:

PART 78--BRUCELLOSIS

0
1. The authority citation for part 78 continues to read as follows:

    Authority: 7 U.S.C. 8301-8317; 7 CFR 2.22, 2.80, and 371.4.


0
2. Section 78.1 is amended as follows:
0
a. In the definition of confirmatory test, in the second sentence, by 
adding the words, ``the fluorescence polarization assay (FP assay),'' 
before the words ``the particle''.
0
b. In the definition of official test, by redesignating paragraph 
(a)(13) as paragraph (a)(14) and by adding new paragraphs (a)(13), 
(b)(5), and (b)(6) to read as set forth below.


Sec.  78.1  Definitions.

* * * * *
    Official test. (a) * * *
    (13) Fluorescence polarization assay (FP assay). An automated 
serologic test to determine the brucellosis status of test-eligible 
cattle and bison when conducted according to instructions approved by 
APHIS. FP assays are interpreted as either positive, negative, or 
suspect. A 10-microliter sample is used. If a sample reads <10 
millipolarization units (mP) above the mean negative control, the 
sample is considered negative. If a sample reads >20 mP above the mean 
negative control, the sample is considered positive. Samples that read 
between 10 and 20 mP above the negative control mean should be retested 
using 20 microliters of sample. If the 20-microliter sample is >20 mP 
above the mean negative control, the sample is considered positive. If 
the 20-microliter sample is still in the 10 to 20 mP range above the 
mean negative control, the sample is considered suspect. If the 20-
microliter sample is <10 mP above the mean negative control, the sample 
is considered negative. Cattle and bison negative to the FP assay are 
classified as brucellosis negative. Cattle and bison with positive FP 
assay results are classified as brucellosis reactors, while cattle and 
bison with suspect FP assay results are classified as brucellosis 
suspects.
* * * * *
    (b) * * *
    (5) Fluorescence polarization assay (FP assay). An automated 
serologic test to determine the brucellosis status of

[[Page 64249]]

test-eligible swine when conducted according to instructions approved 
by APHIS. FP assays are interpreted as either positive, negative, or 
suspect. A 40-microliter sample is used. If a sample reads <10 
millipolarization units (mP) above the mean negative control, the 
sample is considered negative. If a sample reads >20 mP above the mean 
negative control, the sample is considered positive. Samples that read 
between 10 and 20 mP above the negative control mean must be retested 
using 40 microliters of sample. If the 40-microliter sample is >20 mP 
above the mean negative control, the sample is considered positive. If 
the 40-microliter sample is still in the 10 to 20 mP range above the 
mean negative control, the sample is considered suspect. If the 40-
microliter sample is <10 mP above the mean negative control, the sample 
is considered negative. Swine with negative FP assay results are 
classified as brucellosis negative. Swine with positive FP assay 
results are classified as brucellosis reactors, while swine with 
suspect FP assay results are classified as brucellosis suspects.
    (6) The evaluation of test results for all swine shall be the 
responsibility of a designated epidemiologist in each State. The 
designated epidemiologist shall consider the animal and herd history 
and other epidemiologic factors when determining the brucellosis 
classification of swine. Deviations from the brucellosis classification 
criteria as provided in this definition of official test are acceptable 
when made by the designated epidemiologist.
* * * * *

    Done in Washington, DC, this 29th day of October 2004.
Peter Fernandez,
Acting Administrator, Animal and Plant Health Inspection Service.
[FR Doc. 04-24646 Filed 11-3-04; 8:45 am]
BILLING CODE 3410-34-P