Effect of Atmospheric Ammonia and the Stress of Infectious Bronchitis Vaccination on Leghorn Males

Abstract

Ammonia at levels of 0, 25 or 50 parts per million (p.p.m.) was introduced into 12 controlled-environment chambers containing male Leghorn chicks. Ammonia was introduced continuously into the test chambers from the 4th to 8th week of the experiment. An infectious bronchitis vaccination was administered to all chickens at 5 weeks of age. Body weights and feed efficiencies were determined at 4, 6 and 8 weeks of age. At 4, 5, 6 and 8 weeks of age lung and bursae of Fabricius weights, hematocrits and air sac scores were determined.Body weights and feed efficiencies were significantly reduced in the ammonia chambers. The bursae of Fabricius of the ammonia-stressed chickens were significantly larger than those of controls at 5 weeks of age and significantly smaller at 8 weeks of age. Chickens grown in ammoniated environments had significantly larger lungs at 8 weeks. Hematocrits were not significantly different among the treatments. Total air sac scores were significantly higher in the ammonia-stressed chickens at 8 weeks. Results indicated that chickens are affected by the stress of ammonia at levels of 25 or 50 p.p.m. and infectious bronchitis vaccination.