Estimation of body weight using testicular traits of bucks: A systematic review

Abstract

Understanding how body weight relates to reproductive traits in goats is important for improving breeding practices and farm productivity. This review looks at existing research on the relationship between body weight and key reproductive traits, such as scrotal circumference, testicular length, and testicular diameter in goats. Databases such as Google Scholar, PubMed, ScienceDirect, and Web of Science were systematically evaluated, and a total of 650 articles were retrieved. After screening, a total of nineteen (n = 19) eligible articles were selected for an in-depth analysis. These studies were published between 1992 and 2024, with 26% (n = 5) originating from India. The systematic review highlights significant variations in methodologies employed, including predictive models and regression analyses. The result indicated that simple linear regression model was mostly used in predicting body weight with 21% (n = 4) of the articles included. The findings showed that the highest coefficient of determination (R2 = 0.88) was recorded on scrotal circumference using simple linear regression model on goats. These findings indicate a strong correlation between body weight and testicular traits, making these models highly reliable for estimating body weight. The findings of this systematic review suggest that scrotal circumference is a reliable indicator of body weight in goats. The findings of this study can be used to assist farmers with limited resources to select bucks for breeding purpose and improving their body weight.