a disease of the nervous system of young chickens caused by inadequate intake of vitamin E and marked by severe muscular incoordination, tremors, and encephalomalacia followed by paralysis and by renal congestion and failure.
Vitamin E deficiency in chickens affects the brain, causing degeneration, oedema and haemorrhage, especially in the small brain (cerebellum).
Affected young chicks appear unable to walk, they fall on their sides or stand with their heads between their legs. The cerebellum shows gross swelling, with yellow or brown discolouration and pinpoint haemorrhages may be observed. Encephalomalacia can also be found in mature chickens.
Treatment and control
Adequate levels of vitamin E and selenium in the diet of chickens and their parent breeders is of prime importance. Treatment of affected birds with vitamin E preparations (alpha-tocopherol) is effective if the condition is not too far advanced.