HISTAMINE AND SEROTONIN IN EGG-YOLK AND BRAIN-TISSUE OF CHICK-EMBRYO,AND OPAQUE REGION DEVELOPMENT

Histamine and serotonin in egg yolk and brain tissue of chick embryo, and development of opaque region (OPR) therein regarding possession of superior genome related to better growth and/or reproductive efficien cy were studied. Histamine and serotonin in egg yolks of broiler and l ayer strains, larger (58-62 g) and smaller egg (48-52 g) size of WL he ns and in brain tissue of chick embryo of pure WL laying strain and br oiler x layer cross were determined and compared. Along with this, OPR development in relation to egg size and above strain differences were also explored. Results indicate a significantly higher serotonin in b roiler egg yolk in comparison to layers, larger OPR at 18 hr of incuba tion in bigger eggs and that of broiler cross in comparison to smaller eggs and pure layer strain. Significantly higher level of serotonin i n brain tissue of broiler cross was noted as that of layer strain. The se observations point the role of this amine during embryogensis in ac quiring the superior growth oriented phenomena or lower levels may be providing useful orientation for better reproductive efficiency to be performed during postnatal life. However, histamine did not vary signi ficantly (P<0.01) under these situations but in general a short of rev erse trend as that of serotonin is observed.