Reasons for female cats not in estrus:
1. Immature. Female cats usually come into heat for the first time early when they are four or five months old, but some cats may come into heat later.
2. Lack of exercise. Feeding cats too much protein, fat, and carbohydrates for a long time, coupled with lack of exercise, will make cats too obese, which will cause fat deposition in the ovaries, fatty degeneration of the follicular epithelium, and cats showing no estrus.
3. Lack of minerals or vitamins. Lack of vitamin A can cause degeneration of uterine epithelial cells, egg cells and follicle epithelial cells in cats, resulting in follicular atresia or cyst formation.
4. The cat was neutered. Cats that have been neutered will not secrete sex hormones and will not show symptoms of estrus.
5. The cat was bred successfully. Generally speaking, breeding a cat when it is in estrus can stop the cat's estrus. After successful breeding, the cat will be ready to raise a fetus and will not show symptoms of estrus.
