off (one's) feed
Uninterested in eating. That gory horror movie completely put me off my feed. She's been off her feed since coming down with a cold.
off one's feed
Have no desire to eat, have lost one's appetite, as in Even though Mom's gone only for a week, her absence puts Dad off his feed. Originating in the early 1800s and first used only for animals, this colloquial term later was applied to humans as well.