Main symptoms of vitamin A deficiency in chickens

Newborn chicks developed ophthalmitis or blindness due to vitamin A deficiency; 2-3-week-old chicks showed symptoms; 4-5-week-old chicks died in large numbers. Its main manifestations are growth stagnation, emaciation, dyskinesia, yellow disappearance of beak and leg skin. Tears, cheese-like accumulation in the eyelids. Xerophthalmia is almost a fixed symptom of vitamin A deficiency. When the adult chicken was deficient, it appeared emaciation, weakness, loose feathers, yellow legs and beak, watery secretions in nostrils and eyes, and gradually thickened into milk, the upper and lower eyelids were adhered by secretions, the laying rate and hatching rate decreased, and the semen quality of rooster decreased.