Liz Buchanan BVSc MRCVS
Hello - and thankyou for your question and the video. Of course, this could always be behavioural (in that your cat just isn't as hungry as you think they should be), but why would this suddenly develop? - it could certainly prove worthwhile looking deeper. Bear in mind that I don't know what tests have already been done, I wonder whether pancreatitis has been ruled out, which can cause both sickness and nausea in cats, and doesn't show up on many common in-house blood-tests. Most vets have to send a sample off to a lab in order to diagnose pancreatitis and while older vets use pancreatic lipase as an indicator to check further, it has been shown that lipase isn't as reliable as it was once thought.