Correlation and regression of traits associated with age and sex of Japanese quail (Coturnix coturnix, japonica)

Abstract

This study aimed to estimate the correlation and regression coefficients of traits in Japanese quail (Coturnix coturnix japonica) under litter management concerning age and sex. A total of 250 day-old quail chicks were raised for seven weeks, being fed locally available commercial feed. Live weight and weight of different body parts were measured periodically. Correlation and regression parameters for these traits were then estimated. The average body weight of male and female quail at three different weeks (3rd, 5th, and 7th) were recorded as 50.7, 103, 136.08 and 56.01, 108.8, 146.32, respectively. Female quail were observed to be heavier than male quail. The weight of various organs and the overall body weight of quail increased gradually with age. A slight difference in shank length and beak length was observed in both sexes due to increasing age. The correlations of body weight with abdominal fat, gastrointestinal tract, and liver weight in both male and female quail at three different weeks were high and positive. Regression model parameters, including intercept and slope, along with R² values for male and female quail, were positive. Although male quail exhibited lower values for body weight and liver weight compared to females, higher R² values indicated a close agreement between male and female quail in terms of different traits. Male quail had higher values than female quail for abdominal fat weight. However, the study's findings, emphasizing the correlation and regression parameters, can assist farmers and policymakers in making informed decisions for profitable quail farming in Bangladesh.