of bioeconomic models updated to reflect the current structure of the livestock industry, public attitudes toward animal welfare and the environment, and human population demographics that affect the transmission of disease.

In this context, the extent and kind of financial participation required of producers could be explored. For example, participation could be explicit through payment of premiums into an insurance scheme pooling the risks of disease or implicit through self-insurance when a producer absorbs the uncompensated costs of depopulation.

ENDEMIC BOVINE TUBERCULOSIS IN U.S. CATTLE

The committee believes a continuing program is necessary to clear infection from the large southwestern dairy herds and prevent their reinfection, and, when necessary, eliminate infection in other dairy and beef herds. Currently, endemic infection is limited to a few large dairy cattle herds in the El Paso, Texas, area where it has become established in approximately 10 dairy herds. To date these herds have not been depopulated nor has the infection been eliminated by a test and slaughter program. The herd owners are reluctant to absorb the costs of depopulation and have concerns about test performance, results, and interpretation that could affect the accuracy of identification of infected animals. There have also been problems tracking cattle movements, and it has not been possible to exclude all known, as well as unknown, risk factors, unidentified potential reservoirs, and unusual routes of transmission as important factors in the persistence of the infection. Consistent with its view that livestock producers are among the beneficiaries of disease eradication, the committee believes that dairy producers should contribute financially to the eradication program.

The Need for Combined Efforts

The committee is aware of the state-federal-industry meeting that has been held to develop a strategic plan for the eradication of bovine tuberculosis in the El Paso milkshed (U.S. Department of Agriculture, 1992). Successful implementation of that plan could be assured with broad participation of affected producers and livestock handlers and with focused management by USDA.

USDA should assemble and assign a field investigation/management team to the El Paso milkshed to perform and or oversee all testing and test interpretation in infected and exposed herds, to ensure accurate animal identification and tracking, as well as appropriate recordkeeping and data collection, to identify key risk factors, and to enforce quarantine as necessary.

The team should include the appropriate authorized state and federal officials as well as industry representatives. Ideally, the field team should have the discretion to design eradication measures on an individual farm basis. As part of its investigative function, the team should examine other potential reservoirs or vectors of disease (other species of animals on farms including companion animals and humans). Because of the potential threat to human health and potential to be a reservoir of infection, farm workers, including transient workers, should also be tested. The team would also be responsible for producer and community education regarding the problem.



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