One of the advances made when Franz Fischler was farm commissioner was to recognise farm animals as sentient beings rather than agricultural products. This provided a basis for treating animal welfare as one of the planks of multifunctionality. However, a vet who is an animal welfare expert suggested in a talk (under Chatham House rules) that I attended that this could face a challenge under WTO rules at some point in the future.
She noted that most intensive, behaviourally restrictive systems had been or were being phased out – battery chickens, veal crates, sow tethers (the latter only in the UK). Things like veal crates were very obvious system which coud readily be understood by the interested public. The animal welfare problems we were running into now are more complex to do with breeds and genotypes of animals and whether they are fit for the systems they are in. Things like stocking density, length of journey, consciousness after being stunned were easy to measure. Which genotype was going to fit into a production system was more complex.
Of course there can be important differences between member states. The ban on sow tethering in the UK resulted from private members' legislation and did not apply in Denmark. Consumers in the UK seemed to be generally unaware of this difference in production methods. The UK pig industry was on its knees and got little reward for its more animal welfare friendly systems.