Badger cull in Wales

[Garden Witch]

Originally Posted by stripee

Readers be aware that this link has been tampered with to make it look as if it refers to badger experiments.
"http://mic.sgmjournals.org:80/cgi/content/full/148/10/3019"]Aminal testing on badgers to find a vaccine

The poster was unable to spell the word "animal" correctly.

The link is to a paper written in 2002 on the subject of the BCG vaccine as tested in guinea pigs. It does not refer to badgers in any context. The correct link for this paper is Production of avirulent mutants of Mycobacterium bovis with vaccine properties by the use of illegitimate recombination and screening of stationary-phase cultures -- Collins et al. 148 (10): 3019 -- Microbiology

It was obvious to me that you were not saying it was alright to experiment on Guinea Pigs, or indeed any other creature.

What is also obvious to me is that you have met with a wind up merchant.

Trouble is people like this spoil a decent discussion.

Ignore him he is not woth trying to have an intelligent and sincere communication with.

[The Woodman]

Wind up or not, the two main protagonists in the Eryri and stripee show have maintained a decent level of decorum throughout despite obvious polar views.

I cannot be the only one to have followed this thread from the start and have been educated as to the machinations of regional government and other organisations with regard to this issue.

I've enjoyed "listening" to the discussion - it's better than the Archers!

[Eryri]

I've managed to find details of the animal laboratory tests conducted on badgers in research to find an injectable vaccine. In this case, conducted for Fusion Antibodies Ltd, of Belfast. 200 badgers were captured and killed to do a post-mortem analysis to see the prevalence.
To test for prevalence, 133 were free of bTB, 67 infected.

Number of badgers killed = 200.

A further 19 badgers were captured to conduct animal testes in the laboratory. Of which 10 were infected and 8 went onto develop symptoms as a control group. 9 were infected and vaccinated showing that the vaccine was effective for 6 of these badgers over a 24 week period of captivity. All subjects were 'destroyed' for post mortem tests.

Number of badgers experimented on in the lab before being killed = 19.

bTB vaccination testing on badgers in the lab

Evidently, the 'Badger groups', who hail Hilary Benns proposal for continued research into a vaccination rather than a cull, appear to assume that holding badgers in cages and conduction animal tests on them is OK. Usually, the sample to conduct a deployable vaccine would involve a much larger sample than that in this experiment, and it would be necessary to consider the effects on other species, and consideration of natural mutation the organism may develop to overcome the antigens.

[stripee]

"Evidently, the 'Badger groups', who hail Hilary Benns proposal for continued research into a vaccination rather than a cull, appear to assume that holding badgers in cages and conduction animal tests on them is OK. Usually, the sample to conduct a deployable vaccine would involve a much larger sample than that in this experiment, and it would be necessary to consider the effects on other species, and consideration of natural mutation the organism may develop to overcome the antigens. "

If you post false links, Eryri, then it looks as if you are only interested in point scoring over other posters.
I am not in favour particularly of badger vaccine, and I don't think any of it is OK at all. Not the culling, not the experimenting - none of it. I think cattle vaccine would be far preferable as they are the cause of the spread of the disease. The only reason the badger groups have accepted the vaccination programme is in the hope that it will lessen the persecution of badgers by farmers and allow them to focus their attention on cattle measures.

The farming unions especially the NFU are powerful and wealthy, the badger is only a maligned and commercially valueless wildlife species (according to some) and badger charities are not wealthy. It is a David and Goliath situation.

I believe that landowners who do not support the cull in North Pembrokeshire should be allowed to refuse access to the killing contractors. I think it is a serious mistake by the WAG to force people who are ethically and morally opposed to this cull to be forced to comply.

There are many other points you have brought up - palm oil, farmers shooting rabbits, food production, animal experiments which could do with new threads for further discussion.

Some comments today from the Western Mail from Wales:
WalesOnline - News - Letters - Western Mail Letters - Tuesday, 16 March 2010

WalesOnline - Farming - Columnists - Some will break the law for badgers

[hatless]

I've read this thread, but am still confused about some things. Is a cull just a reduction in numbers, or is the intention to exterminate all badgers from the area?

If, as I assume, it's just a reduction, does anyone know the present population, and to what level will they reduce it? Will the cull be repeated annually? How quickly will the badger population recover if left?

How is a cull supposed to help? I'm still unclear how badgers spread bTB. Is it by direct contact with the cows, or by transfering soil or faeces to grass the cows might eat? In either case, won't a reduced population still spread the disease? If so, and if a cull reduces but doesn't eliminate bTB, isn't the logic that badgers should be completely exterminated throughout the country?

Someone said that badgers 'shed' the disease. This isn't a term I've come across before. Immunity, vector, reservoir, infection, resistance are all terms I know, but shed is a new one. What does it mean? Does it apply to individual badgers or to populations? For instance, if there were no cattle in an area, does that mean the badgers would soon be free of TB? Am I right in inferring from the term 'shed' that badgers do not represent a reservoir of bTB?

[Eryri]

A cull is a reduction in numbers, although there are some who have used words like 'exterminate', which is not correct. Over the five year culling period the number of badgers to be culled is about 900, which is 60-70% of the badger population currently in the cull zone.

Badgers excrete Mbovis directly into the environment from lesions in their liver and spleen, ie shedding. It in the form of faeces, urine, sputum and pus. It is possible for a badger to completely shed mBovis bacteria and the lesions to heal, however, they do not become immune. Re-infection can take place, and so the process continues. The idea of a vaccine is to introduce a less virulent form of the bacteria, which keeps the badger immune system active, thus allowing them to shed quicker, giving less opportunity to spread. A cull has the same effect in that as numbers decrease the spreading is reduced. As with any bacterial infection, once the rate of 'new' or 're-infected' animals becomes less than those already with the disease, the infection does out, or becomes incidental.

[hatless]

I think I'll just ask about the numbers in this post. If 900 is 60 - 70% then the population must be estimated at 1400 - 1500. A quick bit of research tells me that only about a third of females have young in any one year (though this may go up if there if plentiful food, or a low density of badgers). From one to six young are born, but two is the most common number. Assuming that males and females are roughly equal, and taking the more conservative figures I calculate:

1400 badgers, 700 of which are female. One third of these, 233, have an average of two cubs, 466 born each year.

So a cull of 900 over five years, 180 a year, is unlikely to have much impact on total numbers.

[Eryri]

Yes, based on your figures, I think that is correct. Obviously, those cubs born to females that do not have bTB will not be infected, and as long as the numbers with the infection are culled, the 'pool' of infection will reduce dramatically, without any long term damage to the species. The main finding of the Irish cull was that relaxation of cattle movement increased the cattle vector, and the main finding of the English cull was that migration of infected badgers into the cull zone increased the badger vector. A cull cannot work without strict cattle controls, and the zone of the cull does not have to be completely badger sealed, but the rate of re-colonisation from outside has to be reduced.

Logically, another factor on preventing infection migrating back into the cull zone from outside, is the rate at which the mainly bTB free population regenerates within the zone. Over the five years, all of the culled badgers will be given a post-mortem, which should indicate how the rate of infection in changing, something not possible with a vaccination programme. We already know the infection rates in cattle, and there should be a symbiotic and reducing relationship between infection in both species. It is evidently not the density of setts but the number of infected and moving badgers during the year. Cubs grow up and move, and male badgers go walkabout for lady badgers, so the timing of the cull in the summer months is important. Existing setts of culled badgers are likely to be re-colonised by a new generation of uninfected badgers the following year, and this is likely to be an increasing feature, for each year of the cull.

There may be moral arguments against culling, but it is most certainly not 'extermination'.

[hatless]

Originally Posted by Eryri

Yes, based on your figures, I think that is correct.

Your figures, actually.

Obviously, those cubs born to females that do not have bTB will not be infected,

This is interesting. If a cub born to a non-infected female will not have bTB, then I assume there is no badger to badger infection happening within setts. Is that correct? So badgers can be infected from their mother, or from cattle, but not from each other.

and as long as the numbers with the infection are culled, the 'pool' of infection will reduce dramatically, without any long term damage to the species.

But will badgers be caught and tested for infection before being killed? There's no other way to cull selectively, is there? I would have thought they would have been killed indiscriminately. As the numbers of badgers will remain steady, with reproductive growth easily resupplying those lost to the cull, is there any reason to think the amount of infection will reduce?

The main finding of the Irish cull was that relaxation of cattle movement increased the cattle vector, and the main finding of the English cull was that migration of infected badgers into the cull zone increased the badger vector. A cull cannot work without strict cattle controls, and the zone of the cull does not have to be completely badger sealed, but the rate of re-colonisation from outside has to be reduced.

When you speak of re-colonisation it sounds as if you do mean local extermination, rather than a reduction in numbers. You are envisaging some areas having all, or almost all, of their badgers killed. Are the 180 badgers to be killed each year to be taken in a sort of patchwork method across the area?

Logically, another factor on preventing infection migrating back into the cull zone from outside, is the rate at which the mainly bTB free population regenerates within the zone. Over the five years, all of the culled badgers will be given a post-mortem, which should indicate how the rate of infection in changing, something not possible with a vaccination programme. We already know the infection rates in cattle, and there should be a symbiotic and reducing relationship between infection in both species. It is evidently not the density of setts but the number of infected and moving badgers during the year. Cubs grow up and move, and male badgers go walkabout for lady badgers, so the timing of the cull in the summer months is important. Existing setts of culled badgers are likely to be re-colonised by a new generation of uninfected badgers the following year, and this is likely to be an increasing feature, for each year of the cull.

There may be moral arguments against culling, but it is most certainly not 'extermination'.

Now I'm very confused. If it's movement of badgers, surely killing them by the settfull is the worst possible thing you could do. A patchily culled population will move around much more than a stable one, as excess population from one area recolonises empty setts. Why do you think a sett would be recolonised by uninfected badgers? I don't see how a cull is going to reduce the infection rate amongst badgers.

[GavinWheeler]

Originally Posted by Eryri

A cull is a reduction in numbers, although there are some who have used words like 'exterminate', which is not correct

Cull(verb): To separate, select, or pick out; to choose and gather or collect; as, to cull flowers. So a 'cull' would normally be a selective reduction in numbers, and the idea of a non-selective cull such as the proposed badger 'cull' is a blatant bit of spin from the assembly - 'culling' sounds neater and more surgical than 'killing'. Since they will be killing every badger they can catch, 'exterminate' would be at least as appropriate a word to use as 'cull' but of course those who indulge in spin hate having their opponents do the same back to them!

Originally Posted by Eryri

A cull has the same effect in that as numbers decrease the spreading is reduced.

Except of course that the ISG report found the opposite. From the Final report of the ISG:
"Culling profoundly altered the prevalence and distribution of M. bovis infection in badgers. Statistical analyses adjusting for variables such as age, sex, triplet, and various measures relating to the probability of detecting infection, revealed that prevalence rose on successive proactive culls (Woodroffe et al., 2006b). Overall, by the fourth cull the prevalence of infection was approximately double that recorded on the initial cull (odds ratio 1.92, 95% confidence interval 1.51-2.45) after adjusting for other factors (Woodroffe et al., 2006b). Because of this rise in prevalence, the reduction in the density of badgers achieved by proactive culling was not associated with an equivalent reduction in the density of infected badgers (see Table 4.9)." (my emphasis added)