Prediction of body weight from body volume of Savanna goats in Limpopo province, South Africa

Abstract

Savanna goats is one of the South African commercial meat breeds. This study was conducted to predict body weight from body volume (BV), heart girth (HG) and body length (BL). A total of 139 savanna goats of the age between 1 and 5 years old of different sex (male and female) were used in the study for collection of body weight, body length and heart girth. The animals were kept under semi-intensive production system, where they were supplemented in the afternoon. Body volume was derived using cylinder volume formula from body length and heart girth as the components of model. R-studio software was employed for Pearson correlation matrix to assess the association between body weight, body length, heart girth and body volume. Simple linear regression was used to establish model to predict body weight. Pearson correlation results indicated that BW had a highly statistical significant (p<0.01) correlation with HG (r = 0.90), BV (r = 0.84) and BL (r = 0.66), respectively. Regression model findings indicated that HG had highest coefficient of determination (R2 = 0.81) and lowest mean square error (MSE = 24.85), and BV indicated highest coefficient of determination (R2 = 0.76) and low mean square error of (MSE = 35.07) while BL indicated lowest coefficient determination of (R2 = 0.45) and high mean square error (MSE = 70.80). In conclusion, correlation result suggests that by improving HG, BV and BL will result in improving BW of Savanna goats. Simple linear regression suggest that HG and BV can be used to estimate BW of Savanna goats.