Thursday, October 26, 2006

PreM.testing - 6 months on.

Defra have just released the figures from the pre-movement testing of cattle to be moved within or out of, annual or two year testing regimes; this can be viewed:

http://www.defra.gov.uk/animalh/tb/premovement/monitoring-data.htm

As we have pointed out in previous postings, pre-movement testing is only of value as part of a package, and while the theory of 'preventing spread of bTb' from cattle movements is a heroic gesture, a line on a map - in this case an annual or 2 year testing parish boundary - is not respected by wildlife who have tendency not to read the 'Keep Out' notices.

Our Ben, the minister for Animal Health, carefully cherry picked two of the items in the Industry package earlier this year, while impaling himself firmly on the fence over the third.

So what are the results of the costly and time consuming effort, farmers have put in? Well not surprisingly, they bear little resemblence to the predicted figures, contained in the policy documents drawn up by the pre movement testing group. Bill Madders, its chairman admitted that the exercise had picked up less infection than it was originally anticipated by the group. Which just goes to show, you can do anything with figures. Mr. Madders accepted that data flow from this will no doubt show less than the 700 'new cases' (indicating confirmed infection) predicted in Defra's Regulatory Impact Assessment. In fact at 176 cases, a number of which are almost certainly to show NVL (no visible Lesions) in just 6 months, it has a way to go. But as it is farmers who are paying, there is no pressure on Defra to look at the system at all. Neither does it have a 'sunset clause'. That is to say, as with the post FMD 6 day shut down, pre movement testing has no 'end date'. It stays despite its inability to predict infection, industry costs v. benefit or the level of bTb in GB's cattle herds. More in Farmers Guardian;

http://www.farmersguardian.com/story.asp?storycode=5109

Meanwhile, information about the spread of bTb, as shown by the spoligotypes in slaughtered reactor cattle, compared with indigenous badgers has been undertaken, but rarely used.
We have pointed out before that if cattle to cattle transmission was a serious contender for bTb spread, then the cattle spoligotype map of GB would look like a child's kaleidoscope. Different colours all over the country. But this is not the case, and work done is available at;

http://www.mbovis.org/spoligodatabase/GBmetadata/11.html

The report (a SID 5 / Project code SE3020) which delved into the spoligotype map of GB, describes its results thus:
"In general the spoligotype and VNTR patterns obtained from badger isolates 1972 -1976 were the same as those observed in the same geographical areas toady. This suggests that the geographical clustering of strains has not changed since the first isolation of M.bovis from badgers over thirty years ago."

The authors describe this data "as in sharp contrast to the rapid movement of strains " observed in positive post movement tests on re-stocked herds after FMD. Exactly. These were found by the skin test and slaughtered out; end of story.

The eleven main spoligotypes which have remained "in their geographical areas" we summarise below, adding geographical areas i.e 'shared border' counties together.


Type 9 isolated in 44% Cornwall/Devon 20% Dyfed
Type 17 " 66% Here /Worcs / Glos.
Type 21 " 74% Somerset / Avon
Type 35 " 77% Here / Worcs /Shrops.
Type 10 " 79% Glos.
Type 25 " 79% Staffs / Derbys.
Type 22 " 84% Gwent / Here / Worcs
Type 15 " 89% Cornwall
Type 11 " 93% Devon / Somerset
Type 12 " 94% Cornwall
Type 20 " 95% Cornwall

Thus up to 95 percent of slaughtered reactor cattle were subsequently found to have contracted a strain of bTb of the spoligotype indigenous to its badgery home.

Well, well, well.

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