关键词: 樱桃谷鸭, 体质量, 体尺性状, 相关分析, 主成分分析

Abstract: In order to study the relationship between body weight and body size traits of Cherry valley ducks of different ages,principal component analysis was carried out on body weight and body size traits of 18- and 45-day-old Cherry valley ducks(60 each,half male and half female).The results showed that the largest variation coefficient was found in the body weight of 18- and 45-day-old Cherry valley ducks.There was a significant or a highly significant positive correlation between body weight and body oblique length,shank circumference,chest circumference,sternum length,chest width and back width(P<0.01 or0.05).The shank length of 18-day-old Cherry valley ducks was positively correlated with the semi-diving length(P<0.01) and negatively correlated with the chest circumference(P<0.05).There was a significant positive correlation between shank length and body oblique length of 45-day-old Cherry valley ducks(P<0.05).There were different degrees of association among other body size traits.The results of principal component analysis showed that the body weight and ten body size traits of 18- and 45-day-old Cherry valley ducks could be integrated into five principal component indexes,and the cumulative contribution rates were 85.147% and 87.277%,respectively. Among the five principal components of 18-day-old Cherry valley ducks,the back width,shank length,sternum length,neck length and shank circumference had the highest contribution to principal components. Moreover, the contribution of back width, body weight and body oblique length to principal component 1 was similar.Among the five principal components of 45-day-old Cherry valley ducks,the body weight,neck length,shank length,shank circumference and semi-diving length had the highest contribution to principal components,and the contribution of body weight,body oblique length and chest depth to principal component 1 was similar.In summary,the body weight,body oblique length,neck length,shank length and shank circumference can be the candidate traits for Cherry valley duck early selection and breeding.

Key words: Cherry valley duck, Body weight, Body size traits, Correlation analysis, Principal component analysis