I have often referred to this 2007 article highlighting some of the problems farming a wild animal such as bison under UK laws at the time:
Farming News - Bison and Deer farming in Leicestershire
Would anyone happen to know if the legislation has changed since then? I think there is a real welfare issue with bringing wild animals to a slaughterhouse. I don't see as much of an issue with shooting an animal in the field, as this is, in effect, instant, and no different to culling, with the meat being utilised for human, rather than animal, consumption. It's pretty galling to me that the current policy at Yellowstone in the US is to load surplus animals for a journey to the slaughterhouse, rather than culling them in the field, and there is a great deal of protest around this currently. I feel the same way about venison, and will only eat wild game partly for this reason.
It is a very emotive issue, as clearly shown on this thread, but I would add that there is nothing AFAIK to stop farms, having received breeding stock from zoos some years previously, from 'culling' these animals when deemed to be at the end of their productive lives, just as can happen at some zoos. I know of nothing in BIAZA policy/ Zoo licensing regulations giving responsibility to the collection of origin for the ultimate fate of the 'breeding stock' it sent to a farm.
The only bison farm I know of in Scotland was forced to kill its entire herd of 50 animals last year after some tested positive for TB, so hopefully this wasn't where the Knowsley animals had been sent.
I used to be a vegan for many years, but now eat some meat, although very selectively in terms of how it was produced/how the animal died. There are many kinds of meat-eater, just as there are many kinds of vegetarian and vegan. I get tired of vegans who happily chomp their way through soya/palm oil products without questioning whether this came from cleared forest, just as it irritates me to hear meat-eaters trot out the 'if it wasn't for raising the animal for meat it would never have been born at all' argument (as if this would be a terrible thing), and those meat eaters who will eat steak or chicken breast but who recoil in horror at using more of the animal, such as making bone broth out of a chicken carcass.
To go back to the topic of the thread, wouldn't it be nice to see some real transparency and accountability in how UK zoos operate, to be able to go to Knowsley's website and find an article clearly documenting when, how and why the bison left, and where they went to? Some years ago, I worked in a well-regarded collection that benefited from 'zoo babies' during the summer, only to have no option but to send them to a farm (as founder stock). I won't name the collection or species, but this was done quietly.
I personally would love a cultural shift in this country towards more wild game, given we have numerous invasive and destructive species (rabbits, sika, fallow, muntjac, grey squirrel, some species of duck), readily available as a food source, but would also be very happy to see a system where healthier meat was as common as beef cattle, where field-slaughtered farmed bison could be both included as a serious percentage of our food production, and justified by the zoos who contribute founder stock both on welfare and conservation grounds.