Linear Body Measurements in Sheep and Goat as Predictors of Liveweight at Different Ages in South-South Nigeria

This study was conducted to establish the relationship between liveweight and linear body measurements in sheep and goats and to develop prediction models for estimating liveweight using these measurements. A total of 82 animals (47 goats and 35 sheep) aged between 2 and 36 months were randomly selected from different households and the University of Uyo Livestock Unit. The animals were subjected to the traditional grazing system, and linear body measurements such as body length, height at withers, heart girth, and neck circumference were taken. Linear regression models were estimated to predict liveweight using these measurements. The results showed a significant correlation between liveweight and various linear measurements, with heart girth, body length, and forelimb length being the most reliable predictors. Regression models developed for different age groups revealed high prediction accuracies, particularly in goats aged 16-22 months and sheep aged 2-8 months. the prediction model revealed that forelimb length, tail length and ear width were the variables responsible for 99.9% of the variation in body weight of sheep (R2=0.999). Significant positive correlations were found between body weight and neck length (r = 0.798, p < 0.05), neck circumference (r = 0.775, p < 0.05), body length (r = 0.823, p < 0.01), ear width (r = 0.759, p < 0.05), heart girth (r = 0.867, p < 0.01), and height at withers (r = 0.683, p < 0.05). The study concludes that in the absence of weighing scales, body measurements can serve as reliable alternatives for estimating liveweight in sheep and goats, particularly in rural areas where weighing scales are unavailable.