Age dependent variation in cloacal gland and other measures of Japanese quail
J. MOHAN, K.V.H. SASTRY, J.S. TYAGI AND M. SIRAJUDEEN
Division of Physiology and Reproduction
Central Avian Research Institute
Izatnagar-243 122, Uttar Pradesh
The objective of this study was to investigate the age dependent development of cloacal gland and certain other measures (i.e. fertility, appearance of cloacal foam, body weight, egg production and mortality) in Japanese quail. Fifty-nine pairs of heavy body weight strain of Japanese quail were taken from same hatch. The results of this study indicated the appearance of cloacal foam started around 6th week (42 days) onwards in male Japanese quail By the end of 10th week, all the male birds were producing the cloacal foam. From 7 to 13th week, a rapid increase in the area of cloacal gland was recorded which remained nearly constant up to 41 weeks of age. Subsequently, with the advancement of age, a gradual increase in the area of this gland was noticed through out the period of this study except 53-58th week of age (July- mid August). During this period area of cloacal gland regressed significantly. The percent fertility was recorded below 50% at the age of 7 to 9 weeks. Subsequently, a progressive increase (83.10+3.59%) in fertility was recorded between 10 to 12 weeks of reproductive period followed by a plateau maintained from 13 to 41 weeks in which maximum fertility (92.85+ 0.44) was noticed. Following this plateau, fertility reduced nearly 11% (81.88+ 0.20 mm2) between 42-54 weeks of age. Thereafter, a progressive decline in fertility remained continued with the age and reached below 50 percent after 80 weeks. Further, area of cloacal gland was closely associated with the fertility up to 41 weeks of age. Thereafter, this relationship was broken. A progressive increase in body weight was recorded up to 13 weeks of age. Egg production was found maximum between the ages of 10 to 41 weeks. Subsequently, a decline in egg production was recorded between 42-60weeks, which enhanced again between 61-69 weeks of age and thereafter expressed the reduced pattern of egg production with the advancement of age. During the month of July to mid August a regression in the area of cloacal gland remain associated with the reduction of fertility and egg production. It is of interest to note that 2½ times more mortality was recorded in females than males. This observation needs further confirmation in future.