To my surprise, I found that 3 of my adult sheep (2 female, 1 male) have 50% (!) of their starvation bar gone.
This is impossible.
They have had food in their troughs at all times. What's more, they are on (planted) grassland, and not a single patch of that has been eaten, which would have been the case if at anytime they had had no food in troughs.
They are penned together with cows, and pigs, FYI. The cows and pigs are fine, no starvation hits. (except for the cow who had to pull my wagon for a bit too long)
Did something go wrong with the recent food-quality-eaten-by-lambs update maybe?