"Brock" the badger (Meles meles) is a native wild mammal of Britain (amongst other places). Omnivorous & mainly nocturnal these wonderful woodland shadows should normally live their lives undisturbed in their woodland setts. Yet they have been persistently blamed (often with little evidence) for the occurrence of TB in farm cattle. Recently in a rather disturbing development another UK cull of Badgers has been announced. For now it is restricted to Pembrokeshire; but is there any justification at all?
I normally try to keep my blog posts positive, encouraging a love of nature, but I feel that I must at least make a brief post on this topic. I shall attempt to make this post brief, simple & factual.
TB or Tuberculosis is a bacterial disease affecting a variety of species. There are several different types of tuberculosis bacilli; the one that we are concerned with here is Bovine TB (Mycobacterium bovis). This is a disease whose main effect is to cause progressive lesions in the lungs, with a long and protracted downhill effect on the sufferers health. In the UK infected cattle are destroyed & the farmer paid compensation for this loss.
Whilst this is a complicated field there are some critical facts that need to be known:
- TB transmission is mainly via inhalation – research in sheep shows that 5 inhaled bacterium produce the same infection rates as 13million ingested bacterium
- Recent Research shows that at least 80% of cattle infections are caught from other cattle.
- Emerging evidence from Organic farms suggests that lower density stocking & reduced stress levels decreases the risks of TB outbreaks in cattle
- New outbreaks of Bovine TB in areas previously clear of the disease are evidenced as being due to large scale cattle movements, mainly due to restocking after foot & mouth disease.
- Badgers are a wild reserve of Bovine TB, typically between 2% & 12% are infected. However only a low proportion of infected badgers become infectious.
- Other wild species are also a reserve of Bovine TB including fox, mink, rat and deer. Little research has been done in to the infectivity of these species.
- The main evidence for badger to cow infection comes from an experiment where infected badgers were housed in a building with young calves. Despite these ideal transmission conditions it took months for any calves to become infected.
- Badgers often root their noses in cow pats looking for worms & beetles to eat; cows tend to avoid badger latrines. Thus its more likely that badgers catch TB from cows not vice versa.
- Badgers typically have a relatively small territory of ~200acres, they live in family groups & dispersal is low unless they are disturbed by activities such as culling.
- We have a vaccine for Badgers that is being trialled in England. Initial results show that it gives effective protection to badgers and would therefore negate any transmission, if such a thing happens.
- Vaccinating cattle causes problems for government vets testing cattle. An effective cattle vaccine / test combination is expected by 2014. This would be the most effective solution since it should stop cattle to cattle transmission.
- The last large scale cull in the UK was abandoned. It cost far more than any possible gains. The bill to the tax payer was in excess of £11 million.
- The only long term detailed study of Badger / Cattle TB relationship was carried out by the ISG & reported to government. Over 10 years it showed that cattle TB cases continued to rise despite Badger culling.
- The ISG concluded "badger culling cannot meaningfully contribute to the control of TB in Britain".
- Increased bio-security on farms has been shown to assist in control of disease spread. Keeping wild animals away from feed stores, mangers & watering points are all key to success.
These are the salient points of this issue.
Given the great distress that destroying infected cows causes, it is possible to understand why some farmers may cling misguidedly to the traditional views but if only they would open their minds they should see that a badger cull is not the way forward. As for government, it has access to all the research and to authorise a badger cull must surely be pure folly or worse.
To myself & many others, including eminent scientists, the action plan from these points might be:
- Do not increase wild animal dispersion. Avoid introducing culling.
- Do trial the badger vaccine with a view to large scale deployment if required.
- Do fund an increased rate of research in to a cattle vaccine / test combo. This will enable the EU to change its legislation against cattle vaccination.
- Do increase control on cattle movements from hot spot regions.
- Do encourage farmers to improve bio-security. My own informal observations show that a low level electric fence is very effective at discouraging badgers from grazing land.
I should state that I am not affiliated to any organisation that stands to gain in this debate. My parents were dairy farmers before their retirement and I grew up working on dairy farms. I do however also love our wildlife and try to keep up with current scientific thinking.
For me the conclusions are clear.
What do you think? Vote in my poll.