RELATIONSHIP BETWEEN SELECTED BIOCHEMICAL COMPONENTS OF PLASMA AND EGGS IN THE NIGERIA INDIGENO~SH ENS AND BLACK RARCO LAYER.

Abstract

Thirty (30) each of the Nigeria Indigenous (NI) hens and Black Harsco (BH) layers were reared separately with cocks for a 12-week period of study the association between the plasma and egg concentrations of protein, cholesterol and calcium. Eggs were selected and blood samples collected at 2-weekly interatrial. Both the eggs and plasma were analyzed for protein, cholesterol and calcium concentrations. Three randomly picked hens from each group were slaughtered in the middle of the study for histological sectioning of the ovary, magnum, shell gland and liver. Egg yolk cholesterol concentration was lower while the plasma calcium concentration was significantly higher (PC 0.05) in the NI hens as compared to BH layers. Plasma calcium and cholesterol concentration were positively correlated in the Ni hens but negatively in the BH layers. However, there were generally no significant association between the plasma concentrations of protein, cholesterol and calcium and their corresponding levels in the eggs. Histological examination revealed that of the mucosal folds of the shell gland and magnal tissue were no longer in the layers as compared to that of the NI hens, which supported the higher laying performance of the BH layers. Eggs of the NP hens compared favorably with those of the commercial BH layers in terms of chemical qualities. There was also no association between the concentration of these chemical substances in the plasma and those of the eggs.