What causes false pregnancy in sows?

False pregnancy refers to the phenomenon in which a sow does not actually conceive after mating, but her belly grows larger day by day, the udder gradually swells, and later some clear milk can even be squeezed out, yet she does not give birth, and the belly and udder gradually shrink back.

Causes of false pregnancy in sows: First, due to early death and absorption of the embryo, the corpus luteum of pregnancy does not disappear, causing progesterone to continue to be secreted, as if pregnancy were still continuing. Second, due to malnutrition, the sow's endocrine system is disrupted, and the estrous cycle is delayed or stops.