§ Lord Christopherasked Her Majesty's Government:
Given the increase in bovine tuberculosis in cattle, what research has been undertaken to establish whether (a) there are variations in incidence among organic, beef, dairy and suckling herds, or breeds generally; (b) incidence has been affected by the scale (compared with the past) of in-breeding of dairy stock, increased milk yield from cows, crossbreeding of beef cattle and greater stock movements; and whether combinations of such factors could have altered stamina and disease resistance. [HL4057]
§ The Parliamentary Under-Secretary of State, Department for Environment, Food and Rural Affairs (Lord Whitty)A research study funded by Defra which reported in 2000 suggested that beef herds were three times less likely to have a TB breakdown than mixed dairy/beef herds and five times less likely than dairy herds. It also indicated that between 1986 and 1996, annual TB incidence increased and this increase was particularly marked in dairy herds and larger herds.
Defra is not carrying out any research into the effect on TB incidence of factors such as in-breeding of dairy stock, increased milk yields and cross-breeding beef cattle might have.
Defra has only recently introduced a comprehensive cattle tracing database that allows the impact of cattle movements to be analysed accurately as a variable affecting the occurrence of TB. Analysis of data from the ongoing TB99 epidemiological survey has identified a number of factors which appear to put a farm at greater risk of suffering a TB breakdown and these include the movement of animals on to the farm. Further analyses of TB99 data are being undertaken, and these include the use of cattle movement data (given the early indications of cattle movement as an important factor in the spread of cattle TB, locally and nationally). The TB99 survey also attempts to identify, among other things, if organic farm status and, more generally, the herd type have any influence on TB risk.
An analysis of pre-foot and mouth disease outbreak TB99 data, covering factors that have emerged as having significance for TB in herds, is expected to be published soon in the Royal Society journal Biology Letters.
§ Lord Rotherwickasked Her Majesty's Government:
Why they have disclosed that deer and badger carcasses in the Furness Peninsula Road Traffic Accident Survey were negative for bovine tuberculosis but have not disclosed the results from Cornwall, Devon, Dorset, Gloucestershire, Herefordshire, Worcestershire and Shropshire; and whether the majority of the carcasses from those areas other than Furness tested positive for bovine tuberculosis. [HL4151]
§ Lord WhittyThe survey being conducted in the Furness Peninsual is not part of the road traffic40WA accident (RTA) survey being carried out in the seven counties. The purposes of the two separate RTA surveys differ—in Furness the objective was to check if TB was in the local wildlife populations, by using road-killed carcasses as a sample resource, since this would help to inform us of the appropriate TB testing frequency to apply. As the absence of TB in any carcasses checked was informative within the broad purpose of the survey, it was logical to disclose the information to the public.
The purpose of the much larger survey in the seven counties is to obtain region-specific estimates of infection prevalence in badgers. The independent scientific group has advised that before these prevalence estimates can be interpreted, the data must be compared with those from the randomised badger culling trial, matching the two datasets in time and location as far as possible. This comparison will, it is hoped, tell us how well such surveys reflect the level of TB in badgers, and whether such surveys could be used reliably to detect the spread or the increase of TB to, or within, an area and hence flag an increased risk for cattle. Release of data should await the time when they have been suitably analysed and conclusion reached. This work is in hand and results are expected to be published later this year.