Biology Reference
In-Depth Information
There were two ways to participate in the program. Information could
be collected through a Web-based interface or by paper format that could
be mailed or faxed to LPZ. The online database was secured with multiple
firewalls and data encryption; access required a username and password
acquired from LPZ. Confidentiality was an important part of the program as
the consequences of announcement of TB found in a zoo could significantly
affect gate receipts as well as the institution's ability to transfer animals to
other zoos, as is often called for by AZA's Special Survival Plans (SSP) in
order to maximize genetic diversity among zoo animals. Only two parties
had access to all the data within the system: the project manager at LPZ and
the system technical manager responsible for maintaining the Web site and
database.
The intradermal tuberculin test is the primary screening test for TB in
domestic hoofstock. However, no standard TB testing protocols were in place
for zoological institutions, even though AZA and AAZV recommend testing
for TB in zoo animals. The AZA Ungulate Tuberculosis Monitoring Program
was designed to collect information on all possible test types for TB, includ-
ing bacterial culture, PCR, histopathology, ELISA, and acid-fast testing. An
additional open-ended data collection sheet allowed for descriptions of any
other testing methods used.
5.2.4 results
In its 3 years of operation, 17 zoological institutions representing 14 states
participated in the monitoring system. These zoos submitted data on a total
of 326 TB testing events for 278 animals, which represented 56 different spe-
cies of ungulates.
The primary intradermal tuberculin test was by far the test of choice for
TB, accounting for 87% of the test data submitted to the system. That percent-
age rises to 99% if secondary confirmatory intradermal tuberculin tests are
included. The other test results submitted to the system were from histopa-
thology examination and acid-fast testing.
Of the 278 animals, 4 (1.4%) reacted to the primary intradermal test, and 23
(8.3%) were suspect positive. Secondary confirmatory test data were submit-
ted for 14 of the 23 suspect animals; 13 (93% of the confirmatory test results)
were negative on the second test and one (7.1%) remained suspect positive.
This suggests a low specificity for the tuberculin test in exotic ungulates,
but additional data supporting this relationship are required to make this
conclusion with certainty.
5.2.5 evaluation of the System
In order to assess the degree in which the AZA Ungulate TB Monitoring
Program met its objectives, a comprehensive evaluation was performed in
2008. As part of the evaluation, a survey was offered to all AZA institutions,
