Bovine TB testing under scrutiny

Gareth Enticott
Gareth Enticott

Planned changes to the way vets are allowed to conduct TB tests could have a dramatic impact on rural veterinary practices and fail to address quality control issues surrounding tests for bovine tuberculosis, University research has found.

The Animal Health and Veterinary Laboratories Agency (AHVLA) recently announced their intention to require veterinary practices in England to competitively tender for TB tests in specific geographical areas. Proposals from the AHVLA suggest their preferred solution is for a groups of veterinary practices to work together to bid for testing contracts.

Research by Gareth Enticott funded by the Economic Social Research Council (ESRC) suggests that these plans will have a considerable impact on the provision of rural veterinary services and may not deliver expected financial or quality benefits.

Enticott, of the Centre for Business Relationships, Accountability Sustainability and Society, said: "Rural practices in some parts of the country have become hugely reliant on TB testing: it underwrites their ability to provide veterinary services in rural areas. Practices that miss out on a contract are going to suffer".

The AHVLA’s preference is for a network of veterinary practices to work together. However, based on research in New Zealand, Enticott warns against this approach: "New Zealand contracted TB testing starting in 2003 but most of the contracts have gone to a state owned enterprise that had previously done all the testing. Veterinary practices have not had much of a look in, and business models that relied on a network of practices to deliver testing were judged too risky as they failed to deliver the required testing".

Enticott also suggests that the AHVLA will not deliver improvements in the quality of the testing because it ignores the reasons why poor quality testing exists. Enticott’s research suggests that the quality control issues that concern AHVLA are related to the conflicts of interest in the way testing is organised and the lack of enforcement by Animal Health.

"If you are really concerned with quality control," says Enticott, "the best thing is to have independent testers. Having technicians rather than vets would also help address these problems. In the system advocated by AHVLA, however, the cost of monitoring these quality issues may cost more money than is saved through a competitive system."

Enticott’s work also finds that male vets are statistically more likely to find cattle infected with bovine TB (bTB) than female vets. Enticott says: "There is no clear reason to explain these differences. One explanation may be that female vets are often younger, newer to bTB testing and less experienced than male vets. This might mean that they are less likely to classify borderline cases as positive. Similarly, older (male) vets may be more likely to classify borderline cases as reactors because of their bTB testing experience or close relationships with farmers."

Enticott says the results have implications for future quality control methods: "The government has been concerned about the quality of bTB testing for some time. Countries like Ireland already use a system of performance indicators to audit testers. But these results show that method to be too simplistic and could lead to false comparisons between vets. A better way of dealing with quality control would be to reduce the conflict of interest that exists when vets test farmers who are also their clients."