Low feed intake syndrome in weanling pigs is the cascade that starts when a piglet fails to eat in the first days after weaning. Nutrient deprivation suppresses mitochondrial function and antioxidant capacity in the gut. The intestinal barrier loosens. Microbial and immune signals reach the brain, and the hypothalamus switches on immune and appetite-suppressing pathways. Hormones like PYY, insulin and leptin fall out of step. The pig stays small, stays off feed, and even when growth partially catches up weeks later, the physiology never fully resets. Somewhere between a quarter and half of all pigs entering the nursery go through some version of this. That is the short version. The…