Assessment of Relationship Between Body Weight and Biometric Traits Using Path Analysis in Kenyan Domesticated Rabbits

Abstract

Rabbit raring in Kenya is a steadily growing industry which is contributing towards enhancing household food security and income of resource poor farmers. Relationship between body weight  and eight biometric traits (ear length, tail length, nose-to-shoulder length, chest circumference, thigh circumference, abdominal circumference, body length and rump width) was determined in 430 rabbits comprising 255 females and 175 males using path analysis. The animals were randomly sampled from thirteen counties in Kenya. Pair-wise correlations among body weights and linear body measurements were positive and highly significant (r = 0.250-0.703; P<0.01 for male rabbits and r = 0.193-0.671; P<0.01 for female rabbits). Path analysis revealed that the highest direct effect on body weight in male rabbits was realized through chest circumference followed by body length, ear length, thigh circumference and tail length in that order. The direct effects of abdominal circumference and rump width were statistically not significant (P>0.05) while nose-to-shoulder length had negative direct effect, hence these variables were excluded from the final regression model. The final regression equation of the male rabbits included ear length, tail length, chest circumference, thigh circumference and body length with a coefficient of determination (R²) of 0.636. Path analysis for the female rabbits showed highest direct effects was realized via chest circumference followed by body length then ear length in that order. The direct effect of tail length, abdominal circumference and rump width were not significant (P>0.05) while nose-to-shoulder length had a negative direct effect on body weight, hence all these variables were excluded from the final regression model. The final regression equation for the female rabbits included ear length, chest circumference and body length with a coefficient of determination (R²) of 0.567. The prediction coefficients obtained in this study could therefore be used in weight estimation and breeding programs to improve meat production in rabbits.

Keywords: Body weight, biometric traits, path analysis, rabbits, Kenya.