Relationship between Distribution of Shell Gland Pigment and Deposition of Egg Shell Superficial Pigment in Japanese Quail, <i>Coturnix Coturnix Japonica</i>

Abstract

The present experiments were performed to clarify the relation between the distribution of stored pigment in the shell gland and pattern of egg shell superficial pigment in Japanese quail.Eighteen quail hens were used. They were maintained in individual cages and exposed to a 14h, photoperiod. The shell gland was excised shortly before onset of pigmentation. This shell gland and the shell of the egg laid on the preceding day by identical hen were cut into four parts symbolized a, b, c and d, in order from caudal to cephalic or from pointed end to blunt end, and each segment was extracted with HCl-methanol solution for porphyrin pigment.The measurements of shell gland pigment (w/w) revealed that it tended to be less accumulated in both end sides of the shell gland (a and d) as compared to its equatorial region (b and c). On the other hand, relatively low correlation was found between the corresponding symbols in four segments of the shell gland and shell in relation to the amount of pigment. However, when two adjacent segments were coupled, such as a+b, b+c and c+d in each of the shell gland and egg shell, appreciable correlation was found between the corresponding coupled segments. The correlation coefficients were 0.23, 0.38 and 0.54, respectively.From the present results, it is suggested that the characteristic pattern of superficial pigment on the egg shell surface in individual quail hen may have a relation to the uneven distribution of stored pigment in the shell gland.