Saturday, November 29, 2008

More on Bambi

Early in 2004, we asked the Minister of State for Agriculture what assessment she had made of the influence of wild deer in the spread of TB to cattle.
The answer given on the minister's behalf by baby-Ben Bradshaw was as follows:
In Great Britain there is very limited evidence that deer have been responsible for transmitting tuberculosis to cattle. Wild deer in GB have generally been considered a sentinel or 'spill-over' host of infection in cattle and other wildlife, rather than the cause of it. (26th. Jan 2004: [148655] Column 2W)
The answer goes to say that Defra funded a survey of wildlife in the SW of England, to estimate the prevalence of m.bovis in deer.

This week, more of those results are published, with the overview similar to that expressed in the PQ above. Deer are not a cause of tuberculosis in GB, they are victim of a maintenance host, whose name Defra dare not speak.

Two reports are released from DEFRA "that build on the evidence base on bovine TB in deer". The first is the final report from the South West England and Cotswolds Survey of Tuberculosis in Deer. The second is a related quantitative risk assessment of the risk of tuberculous transmission posed to cattle by wild deer.
"The results of the deer survey show that on Forestry Commission land in the South West Peninsula, bovine TB is present at a very low level (less than 1 per cent, except in one area where it is present at 3.8 per cent in fallow deer). In the Cotswolds, high prevalences were found in two of the three areas sampled (15.9 per cent and 8.1 per cent) particularly in fallow deer. In all areas surveyed, fallow deer were the species most likely to have the highest level of infection with M. bovis.
The key results of the second report, the quantitative risk assessment, indicate that deer are likely to pose a lower TB risk to cattle than badgers throughout most of South West England and Wales."

Quote taken from DEFRA news release.

We note that Defra stated in 2004 that deer were a 'spill-over' host of tuberculosis. Defra reiterated this week that "deer are likely to pose a lower risk to cattle than badgers throughout most of the South West England and Wales".
Deer are subject to a management strategy described by Defra thus:
"In England, the government 'intervenes' in a number of ways, but most importantly through setting legal parameters for deer management. Forest Enterprise, the government agency responsible for managing the nation's forest estate, intervenes more directly [they mean a cull to control numbers and disease within populations - ed] and is actively involved in managing deer within its forests.(PQ [158002] )"

And badgers? That elephant-in-the-room, who Defra say pose more of a threat of tuberculosis transmission to cattle than deer?
22nd March 2004: Col 510W [158715] ....M. bovis is endemic in British badgers."

What about them?


Anonymous said...

Yep, deer and badgers get TB from cattle, as do numerous other species of mammals all over the world.

When TB prevalence in the host species (cattle) goes down, the prevalence in wildlife (badgers) goes down too.

Jim said...

Anon 11.30: ...and cattle get TB from badgers. Moreover, as previous comments on this blog have pointed out, cattle don't give it to other cattle very easily (or, I imagine, to deer). See Defra's own studies.

But the main point surely is this: Until we get on top of all sources of infection, we are never going to eradicate TB. Why should it be only our cattle that have to be killed? I still find it hard to comprehend the irresponsibility of the badger lobby in failing to face up to this simple fact. (Yes, we would all much rather have an effective vaccine, but that is still years away, and we're facing a record 40K cattle expected to be slaughtered this year.)

Matthew said...

On badger vaccination, the silence of the badger groups is deafening.

In an answer (of sorts) to Geoffrey Cox MP at the recent EFRAcom meeting, Gabrielle Edwards admitted that in an endemically infected population, vaccination efficacy would be compromised.

As in not work at all?
As in slower? How slow?
Or as in infection + vaccination = double dose of bacteria = death.

For injectable delivery, how are candidate animals receiving their jab to be marked?
Is the vaccine a one off, or to be administered annually?
How is oral bait to be delivered to all members of the group, and not just the alpha member(s)?
And how is such bait to be kept away from cattle either as virgin peanuts, scattered by birds etc., or recycled through badgers into field latrines?

As the minister is hanging his hat on vaccination, we are curious.

Anonymous said...

Dear Jim
Because it's NOT EFFECTIVE to kill wildlife.
I do wonder what is it about this simple fact (now proved over and over again at the cost of tens of thousands of badgers' lives) that the pro-cull lobby finds so hard to understand?