I feel every vet and vet nurse should be given more adequate training to help wildlife until a wildlife centre can take over care of the patient. 

Imagine if we said we didn't have the resources, training or time to care for a dog or a cat or a rabbit and so, opted for euthanasia on those grounds? 

I’ve worked in several types of practices, some with highly qualified exotics vets and nurses where wildlife has been treated well and their natural habitats considered when treating them in practice. Other practices have been ill equipped to properly look after and care for wildlife taking into account their natural behaviours and needs. Thankfully in all cases wildlife rescue and rehabilitation centres have been locally on hand to help one treatment had taken place or was ongoing but could be managed in a non clinical environment. I personally sit on the fence when it comes to should we treat them or euthanasia. For lots of wildlife stress of being sick, in a totally foreign environment (even if we try our best to provide what they need the contact with humans, environment, scents, noise etc that comes in practice is inevitably going to add stress to the animal) treatment (medication or sometimes even meeting the animals nutritional needs) etc can be so much to undergo that I can see a reason on welfare grounds to euthanise. However, I think we as a profession feel we should give that animal a good chance at recovering and getting back to the wild. It goes without saying (in my opinion) that if the animal is obviously seriously injured that they should be saved from further stress, fear, pain and euthanised. I think if we could switch our feelings off and put ourselves in the animals position then more wildlife brought into practice when injured would be euthanised.