Effect of age on cloacal gland development, fertility and other measures in Japanese quail

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) of Japanese quail (Coturnix coturnix japonica). Fifty-eight pairs of Japanese quails heavy body weight strain were randomly selected from flock of the same hatch. The results indicated that cloacal foam appeared around 6^th week and by the end of 11^th week, all the male birds were producing the cloacal foam. From 8 to 10^th week, a rapid increase in the area of cloacal gland was recorded thereafter remained nearly constant between 11 to 43 weeks of age. In the second year (55 wks onwards), with the advancement of age, a fluctuation in the area of cloacal gland was noticed. The maximum regression of the cloacal gland was occurred at the end of both years (July-August: 55 to 60 weeks or June-July: 96 to 104 weeks of age) when summer days associated with humidity. The percent fertility also followed a similar course with a rapid increase between 8–10 weeks and a plateau between 11–43 weeks of age. Following this plateau, fertility reduced nearly 11% between 44–54 weeks of age. Thereafter, a progressive decline in fertility remained continued with the age and reached below 42 percent after 80 weeks. This study indicated that the area of cloacal gland was closely associated with the fertility up to 43 weeks of age. Thereafter, this relationship was broken. Similarly, egg production was found maximum between the ages of 11 to 43 weeks. Subsequently, a decline in egg production was recorded throughout the investigation. A progressive increase in body weight was recorded up to 10 weeks of age. It is of interest to note that during two years study, nearly two times more mortality was recorded in females than males. From this study it could be concluded that cloacal gland of male Japanese quail remain correlated with fertility up to 43 weeks of age and regressed drastically under heat stress.