THE BURSA OF FABRICIUS AS AN INDICATOR OF CHRONIC STRESS IN IMMATURE CHICKENS*

Abstract
Repeated injections of ACTH or repeated stress in the form of immobilization resulted in a statistically significant regression in weight of the bursa of Fabricius in young chickens. Repeated injections of plasma from immobilized birds into other birds resulted in a similar regression when compared with bursae from birds injected with plasma from non-stressed birds. Results indicate that bursal regression can be used as an indicator of chronic stress in young chickens.