Many thanks for your patience. What you are faced with here is a potential negligence situation by the vet. Negligence occurs when a party owes another a duty of care and they have gone and breached that duty through their actions. When considering their actions, they will be judged by comparing them to those of a reasonably competent party in their position and whether the actions of the guilty party fell significantly below that standard.
To apply it to your situation: a court would look at what a reasonably competent vet would have done in these circumstances and if they would have been expected to provide a heat source for the pups. This would depend on whether this is a common practice in such situations and if it is, then there is an argument that any reasonable vet would have been expected to do the same.
If your vet failed to do this, the is an argument that their actions fell below the standard expected of a competent vet in their position and as such there is potential negligence. The next thing is to show that the results were reasonably foreseeable, i.e. Was it a reasonable expectation that the failure to provide a heat source would result in the pups' health being seriously affected by it,mor was it just a freak accident that it happened. If there was a clear expectation that there was a good chance they would be affected as a result, then reasonable foreseeability can likely be proven.
So all of this means that you can potentially consider a claim for negligence against the vets. You will not be able to claim for the stress or emotional distress and as the pups will simply be consider an inanimate object under law, you would be seeking compensation for their value.
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