16 May 2007

6 minute read

Europe

Ms Coughlan said that the wildlife strategy implemented by her Department, which includes the targeted removal of badgers, is underpinned by peer reviewed research studies that demonstrate that the culling of infected badger leads to a significant reduction in the incidence of TB in cattle. The published results of the Four Area Project carried out in counties Cork, Monaghan, Donegal & Kilkenny demonstrated a significant reduction in TB levels in cattle in the removal areas over the five years (1997-2002) of the trial, compared with levels observed in the five years prior to the commencement of the trial. In particular, the total number of herd restrictions in the removal areas for the study period (222 cases) was almost 60% lower than the pre study period (537 cases). For the reference areas, there was little difference compared with the national trend in the incidence of the disease in the two periods.

Ms Coughlan said that, under the wildlife strategy, badgers are captured under licence issued by the Department of Environment, Heritage and Local Government where they are implicated in an outbreak of TB. Capturing is undertaken only in areas where serious outbreaks of Tuberculosis have been identified in cattle herds and where an epidemiological investigation carried out by the Department's Veterinary Inspectorate has found that badgers are the likely source of infection. Ms Coughlan said that the agreement with the DOE does not allow for total removal of badger populations and there is no question or possibility of badgers being exterminated as suggested in the Report.

With regard to welfare issues, Ms Coughlan said that the restraints used in the capture of badgers are approved under Section 34 of the 1976 Wildlife Act and, contrary to the allegations of Badger Trust, are designed with a stop specifically so as not to tighten beyond a predetermined point and certainly not to cause strangulation. A condition of the licence granted is that restraints are checked before noon the next day. Capturing of badgers is not permitted during the months of January, February and March in new capture areas. Returning to areas previously captured ensures a lower risk of capturing any badger, and an even lower risk of capturing a female badger and an even lower risk again of capturing a lactating female.

The Minister rejected the finding in the Report that the spread of bovine TB in Ireland is largely due to cattle to cattle transmission. Ms Coughlan said that research in Ireland has shown that cattle to cattle transmission is not a major factor in the spread of TB as evidenced by the fact that, on average, 38% herd breakdown episodes involve just one standard reactor and, even in larger breakdowns, epidemiological investigations do not frequently implicate infection spread via this route. In addition, in breakdowns triggered by a single lesion at slaughter, no reactors are identified in approximately 85% of herds during subsequent herd testing. Furthermore, investigations of disease episodes in Ireland have shown that a relatively small % of all outbreaks were purchased animals positively identified as being the source of the infection. Ms Coughlan also said that research shows that the proportion of badgers that are infected with TB in the vicinity of TB infected herds is at least 40% and that infection by badgers was the single most important source of infection of cattle. In addition, contrary to what is stated in the report, badgers and cattle do share the same strains of TB locally with different strains dominating in both species within the same geographic area when compared with different areas. In view of these findings, her Department had concluded that pre-movement testing of cattle on a widespread basis was not cost effective.

Commenting on the relative levels of bovine TB in Ireland and Great Britain, Ms Coughlan said that the number of cattle slaughtered as reactors did not accurately reflect the incidence of disease. The widely accepted measure of the incidence of a disease is the number of herds in which disease is detected as a proportion of the number of herds tested. On this basis, the incidence of TB in the UK in 2006 was 7% compared with 5.4% in Ireland. In addition, much of the disease in the UK is concentrated in the South West of England, which has a herd incidence in excess of 10%.

Ms Coughlan said that the incidence of TB in Ireland had fallen in recent years. The number of reactors has declined substantially since 1998 from 45,000 to just under 24,200 in 2006 (46% decrease). The number of reactors removed last year was the second lowest in the last twenty years. Ms Coughlan said that, while there were a number of factors involved, her Department was satisfied that the badger removal policy made a significant contribution to the improvement in the situation. Her Department is satisfied that its current badger removal programme is justified and has contributed to the decline in the number of TB reactors and the costs associated with bovine TB. Ms Coughlan said that her Department rejected the finding in the Report that the reduction in the incidence of TB was due to the introduction of new TB tests. Such tests would in fact increase rather than reduce the number of reactors in the short term.

Ms Coughlan said that the objective of the Department is to find a solution that will enable both badgers and bovines to co-exist while at the same time limiting the transmission of infection from one species to the other. In pursuit of this objective, her Department is committed to a research project with UCD on the development of a vaccine for use in badgers that would lead to a reduction in the current high levels of TB infection in that species. It is hoped that this strategy will in the longer term reduce the need to cull TB infected badgers as tuberculosis levels fall in both cattle and badgers. However, any vaccine will not be available for wider use in the immediate future and the existing strategy will remain in place for some time.

In conclusion, Ms Coughlan said that the wildlife strategy implemented by her Department is a pragmatic response, based on sound science, to a complex problem. One of the recognised requirements for the eradication of a disease is that there is a single host species with no external reservoir species at present. The wildlife reservoir is recognised as a major impediment to the eradication of tuberculosis in cattle in states such as New Zealand and Michigan State and to ignore this is tantamount to dismissing one of the basic tenets of eradication. The hope of developing an oral delivery system of BCG that will reduce the impact of tuberculosis in badgers is a realistic one. Confining capturing of badgers to areas where herds must first be identified with proven tuberculosis that was not caused by infected cattle is a further safeguard against unnecessary removal of badgers. Removing heavily infected badgers from localities where cattle breakdowns have been identified can only but benefit the surviving test negative cattle as well as the badgers in the wider area surrounding the removal zones.

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