THE TRUTH – FROM THE HORSE’S MOUTH (NOT MINE)
It’s funny, I am now being accused of spreading ‘myths’ about cattle vaccine. Well, we shall see.
The following piece is long – apologies – but it does give in simple terms the real picture of what is going on out there. And not in my words, but the words of someone who knows a lot better than I.
Recently there have been quotes from the Paterson, Cameron, and even a couple of farmers on the Internet, saying that the cull will be good for badgers … and we, the anti-cull people are being ‘cruel’, because we’re not killing off all those thousands of badgers that are staggering around coughing and spluttering. I realised gradually over the last couple of years, that many pro-cull people talk about this supposed throng of sick badgers, but nobody seems actually to have seen them.
Well, having read the RBCT report, (which I suspect most pro-cull Government officials haven’t) I asked Rosie Woodroffe for exact confirmation.
1) In the ISG experiment, what percentage of Badgers that were killed were tested positive for bTB in the post-mortems?
In the proactive culls (the most useful measure), we caught 1,199 badgers found to be infected, out of 8,863. So, that’s 13.5% of badgers found to be infected. But that average conceals a great deal of valuable information. The proportion of badgers found to be infected rose consistently on successive culls, and it also rose after the foot-and-mouth epidemic in 2001 (when cattle testing was suspended and presumably infected cattle were able to pass on infection to badgers). On initial culls the prevalence varied between 1.6% and 37.2% (the latter after FMD).
2) Of that number, how many badgers actually showed symptoms of the disease, enough to class them as ‘sick animals’?
Very few. Focusing on the adults, 39% of infected adults had any detectable lesions at all. We subjectively assessed about 10% of infected badgers as “severely lesioned” – this translates into about 1.6% of all adult badgers being really sick with TB.
3) Is there any reason to think that percentage would be different now?
No solid reason. We found that, even among infected badgers, the severity of pathology increased over the course of the trial – but we didn’t know why. It’s more likely to be linked to perturbation (as an increasing proportion of badgers were infected at all) than to any background increase over time… hence no particular reason to expect this percentage to have risen in the absence of culling.
It’s unlikely Ms Woodroffe would get this wrong (she did the experiment, and co-wrote the peer-reviewed report paper). And of course we are talking about the worst possible case here, in TB hotspots. Notice that the 39 per cent here is a percentage of 13.5 per cent of the total. So out of the whole number killed, only just over 5 per cent actually had symptoms. The really sick ones are at 1.6 per cent. How can anyone justify killing badgers when 98.4 per cent of them are functioning, parenting, socially participative animals? To achieve what, exactly?
4) Is the Government’s estimate of an improvement of ‘up to16 per cent’ in breakdowns based on any science that you would regard as valid? Was it published? Peer-reviewed?
Yes … this is based upon calculations from a published paper on which I was a co-author. However the method is quite idealised. It draws upon the reductions in cattle TB that we recorded in the RBCT inside, and up to 2km outside, proactively culled areas, These effects are then extrapolated to larger areas assuming an idealised perfect circle. This is optimistic because a circle has the smallest possible perimeter of any shape – so in the real world the detrimental edge effect is likely to be greater than in the idealised assumption. Also, the 16% figure assumes a lower background incidence of cattle TB on the “adjoining land” than inside the culling area, which reduced the net benefit – if baseline incidence is assumed the same inside and outside the culling area, then the estimated net benefit is reduced to 12%. Furthermore, both of these central estimates ignore the associated confidence intervals… these are a 3.1% to 21.8% reduction for the 12% scenario, and a 7.9% to 24.2% reduction for the 16% scenario.
It is also worth noting that the paper in which we published extrapolations of this sort made the following point:
It is important to note that the effects described here relate only to culling as conducted in the RBCT, ie deployment of cage traps by highly trained staff in coordinated, large-scale, simultaneous operations, repeated annually for five years and then halted. As described elsewhere, culling-induced changes in badger numbers and movement patterns mean that culling which is small-scale, patchy, short-term or asynchronous is very unlikely to provide comparable reductions in the incidence of cattle TB and could well prompt increases.
5) What can we say is the true likely effect of this series of culls, over 10 years ?
We really don’t know! The 12-16% figures are the best available estimates, but they assume the same type of culling as the RBCT. There are so many differences between what is planned and the RBCT culls (which were more or less military in their implementation) the outcome could be anywhere from a tiny bit better than the RBCT (but I frankly doubt that) to making things much much worse.
This is the truth about this cull which some farmers have been led to believe will make life better for them. It’s a tragedy. Nobody benefits. So why? Nobody benefits except some toffs who would hate to lose this battle, because it would mean that Britain actually recognised that wild animals have feelings, and rights. It would severely damage their chances of resuming their foul blood-sports. Think about that. Think about that if you hear tomorrow that they are already blasting away at defenceless black and white animals.
I need to wrench myself away soon, and make some music. This ‘political agricultural’ world has a very bad smell.
Cheers
Brian
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