Poultry lacks vitamin A, which not only damages itself but also reduces the constitution of the offspring and affects the sustainable development of the poultry industry. Therefore, this must be given sufficient attention. 1 species of vitamin A deficiency in poultry 1.1 Vitamin A deficiency in breeders According to Zhang Zhinian, the breeder's vitamin A deficiency and its offspring are symptomatic. 1.1.1 breeder's own symptoms: 1 common symptoms of male and female breeder: As the rhodopsin in the eye is reduced, photoreceptor cell function of the retina is reduced, resulting in night vision loss (night blindness), and even no night. In addition, due to degeneration of the lacrimal gland epithelium, parotid secretion decreased, the eye lost smoothness and dry eyes appeared; nasal cavity mild inflammation, out of a large number of secretions; body weakness, weight loss, feathers messy, cocks pale. Two types of hens showed symptoms of diminished ovarian function, decreased egg production, and reduced fertilization rate and hatching rate. Three kinds of rooster symptoms: decreased libido, reduced sperm count, decreased sperm motility, and reduced fertility rate. 1.1.2 Offspring Symptoms: 1 Embryonic symptoms: Follicular hypoplasia in the hatching of eggs, delayed embryo development; Embryonic eye swelling, dead embryo rate increased. At the postmortem examination of the embryos, calcium phosphate uric acid crystals precipitated in the kidneys. 2 newborn symptoms: hatch late, eyes inflammation, tears, eyelids; ataxia, paralysis and calf yellow fade; growth stagnation, severe death. 1.2 Deficiency of vitamin A in ducks According to Liu Jiusheng, ducks lack vitamin A and both their own and their offspring have symptoms. 1.2.1 Kinds of ducks have their own symptoms: tears in the eyes, thick eyelids under the eyes, and cloudy cornea. The egg production of the female duck decreased, the color of the egg yolk became lighter, and the fertilization rate and hatching rate all decreased. The color of the ankle and the crotch fades. The male sexual function declines. 1.2.2 Embryos and Ducklings Symptoms: The rate of dead embryos in hatching eggs increases and the hatching rate decreases. The lack of vitamin A in ducklings is due to the lack of vitamin A in the breeding ducks. The diseased ducklings had tears in both eyes, accumulated eyelids, and corneal opacity; walking and walking, squatting, and yellowing of the calf; the nostrils flowing and slow growth; severe cases of eyeball subsidence, blindness in both eyes and eventually death. 1.3 Vitamin A deficiency in pheasants According to Lu Jinkui, a professional pheasant in Dafeng City, Jiangsu Province, purchased 3,000 pheasants and began to die at the age of 4 days, with 4 deaths per day. Symptoms: There are secretions in both eyes, vision loss, inconvenience for foraging, infirmity, thinning of the sputum and paw. Autopsy: There is a large number of pearl-like nodules in the intestinal mucosa of the mid-lower intestine. Diagnosed as vitamin A deficiency, the reporter pointed out that the pheasant suffers from vitamin A deficiency, which is caused by lack of vitamin A in the pheasant, which results in the lack of vitamin A and reserves in the breeding chickens and young chicks. 2 Control measures 2.1 To prevent the supply of carotenoid-rich feeds, such as alfalfa, carrots, squash, yellow sweet potato, and yellow corn, for a long period of time. 2.2 Treatment 2.2.1 Oral administration of vitamin A preparations: 1 Vitamin A capsules: Each capsule contains 25,000 units of vitamin A, and breeding birds and male birds add 4000 units per kilogram of feed. 2 Cod Liver Oil: Each milliliter contains vitamin A850 units, vitamin D85 units, and every day each species of birds is taken orally 1.0 to 1.5 ml, and the diseased chicks take 1 to 2 drops orally every day. 2.2.2 injection of vitamin A preparation: Vitamin AD3 injection, containing 5 million units of vitamin A per milliliter, vitamin D 305000 units, each bird 0.5ml per day, intramuscular injection. 2.2.3 other treatment measures: more than eye secretions, with normal saline or 1% to 2% boric acid solution rinse. Rushan Jinguo Food Co., Ltd , https://www.jinguofood.cn