Thirty-three live 9-day-old broiler chicks were submitted for laboratory evaluation because of blindness. Blindness was observed in up to 1% of 25,000 birds from four different houses. All the chicks were from the same breeder source. Blindness was apparent when the chicks were 2–3 days old. Clinically, the blind chicks were smaller than their counterparts, were unable to find feed and water, and wandered aimlessly. Necropsy did not reveal any lesions. Two chicks examined clinically at 14 days of age lacked pupillary reflexes after light stimulation, and the anterior and posterior segments of the eye were normal. Microscopically, degeneration of photoreceptor cells characterized by vacuoles was evident at 9 days of age, and rosette formation of the retina, disorganization of retinal layers, synechia of the retina with mild inflammation in the choroid, and proliferation of the retinal pigment epithelial cells were evident by 15 days of age. Because the chicks came from the same breeder source and the incidence of blindness was low, a probable genetic etiology is suspected as the cause of blindness in this flock.
How to translate text using browser tools
1 July 2003
Blindness Due to Retinal Dysplasia in Broiler Chicks
H. L. Shivaprasad,
Ruediger Korbel
ACCESS THE FULL ARTICLE
Avian Diseases
Vol. 47 • No. 3
July 2003
Vol. 47 • No. 3
July 2003
birds
eye
genetic disease
pathology
poultry
special senses