Determination of beta-adrenoceptors in myocard of different strains of chickens - A study for clarification of the frequent occurrence of sudden death syndrome and ascites in male broiler chickens

The present investigations should contribute to clarify the importance of b eta-adrenergic system in myocard for the triggering of sudden death syndrom e and ascites in male broiler chickens. Therefore it should be verified if differences in density of beta-adrenergic receptors in myocard exist in sev eral strains and sexes of chickens. We showed in both male and female broil ers that the receptor density was significantly higher as in chickens of th e laying strain. There were no significant differences in receptor density between sexes in both investigated strains as well as in K-D-values between all groups. The latter finding is referred to the absence of differences i n receptor affinity for H-3- dihydroalprenolol between the groups. Clarific ation of the question if chronic heart failure is in contrast to myocard hy pertrophy accompanied with reduction of beta-adrenergic receptor density or receptor affinity in broilers too, as could be shown in other species, has to carried out in further investigations.