Wednesday, August 16, 2006

Tb Policy and the badger culling trials.

In a letter to the Veterinary Record, August 12th., eight leading bTb veterinary experts continue to pile the pressue on the RBCT, or to be more precise, the Krebs’ exercise in badger dispersal.
Responding to a letter from the Chairman, Lord High Executioner, Judge and Jury of the ISG and the trial, Professor John Bourne, Messrs. McDiamid, Daykin, Smith, Ashton, Davies, Turnbull, Muirhead and Gallagher write that:

"…the use of ‘robust statistical methods’ will not derive the correct assumptions from flawed basic data."

They point out that:
"A high trapping efficiency was fundamental to the proper conduct of the trial, yet Defra, whose staff carried out the actual trapping at the direction of the ISG, conceded a very low efficiency of 20 – 60 per cent". And they remind Professor Bourne of the evidence given to the EFRA committee by one of his own Wildlife Team, in which he describes the poor conduct of the trials.

Using answers to Parliamentary Questions archived on this site, they remind the good Professor that during his badger ‘culling’ trial, "…of 15, 666 traps set, 8981 had been interfered with (57 percent) and a further 1827 (12 percent ) were stolen up to October 2003. And in April 2004, the Minister revealed that the trapping efficiency had been as low as 30 percent" .

They point out that, in their opinion, "that the trials had been compromised as well as the trapping approach, seems difficult to refute, despite the ISG’s protestations".
"While the ISG claims its trials were ‘robust’, the grossly inefficient culling methodology caused social disruption and dispersal of infected badgers on a vast scale, unseen in previous trials" (This was our contributer’s experience too - from Staffordshire to Cornwall.)

The letter concludes by reminding readers of previous work all of which officially recognises the badger as a maintenance host of bTb in the UK, a fact which Bourne and his colleagues tend to skate over with a euphemistic note that "badgers contribute to Tb in cattle", while applying their collective concentration to more cattle based measures.

"It (the ISG) confines its recommendations to ‘more vigorously adopted and applied cattle based measures’. Yet we know from earlier work, not always appreciated by the ISG, that cattle have been acting as sentinels of localised disease in badger communities.
Detection and slaughter of sentinels with even greater vigour, yet not addressing the source they are signalling, must be one of the most irrational epidemiological concept yet. We reiterate our warning that the ISG’s advice based these flawed ‘trials’ must be treated with extreme caution. It is also noteworthy that since 1998, the bTb problem has deteriorated so seriously that herd breakdowns have returned to a level not seen since the 1950’s."

...and still we kill the 'canaries in the coalmine', without listening to the song they sing.

1 comment:

DJBD said...

Why a Krebs trial at all?

It is said that any trial to be accepted by the Scientific community must have 'controls'. But neither the efficient Thornbury nor the Steeple Leeze culls, which gave conclusive evidence that badgers were involved, had 'controls'.

Research Scientists work on the principle that 'the more you look, the more you find and the less you know'. If their knowledge was complete they would make themselves redundant. Obviously when Professor Krebs saw an opportunity for his colleague Professor Bourne, he applied for funding from his employer MAFF to conduct a 'scientific trial'. Had Ministers responsible for the funding, known about Thornbury and Steeple Leeze, it would have been fraudulent to have authorised this trial.

The Krebs trial was not only money squandered, but an opportunity lost.