Predicting Body Weight of Ethiopian Indigenous Chicken Populations from Morphometric Measurements

Abstract

The purpose of this study was to estimate the relationship between body weight (BW) and morphometric measurements of Ethiopian indigenous chicken populations and to develop prediction equations used to estimate BW from body measurements. A total of 621 chickens comprising 134 males and 487 females reared under smallholder management conditions were used for the study. Body weight and morphometric measurements including body length (BL), chest circumference (CC), shank length (SL), and shank circumference (SC) were taken using a hanging scale and a textile measuring tape, respectively. The relationship between BW and morphometric measurements was determined using Pearson’s correlation coefficients (r) and stepwise multiple regression analyses. Descriptive statistics indicated that male birds were heavier than female birds. Correlation results revealed that body weight was significantly and strongly correlated with SL (r = 0.76) in both sexes, and moderately correlated with SC (r = 0.69), BL (r = 0.67), and CC (r = 0.52) in male birds, BL (r=0.68) and SC (r = 0.59) in female birds. Compared to other measurements, SL best predicted BW in both male and female birds, with coefficients of determination (R2) = 0.58. Combining SL with other body measurements (BL, CC, and SC) generally improved the predictive power of the equation. Thus, multiple regression equations that included a combination of the four linear body measurements are more suitable for predicting BW of Ethiopian indigenous chicken populations.

Keywords

• linear body measurements
• linear regression
• model validation
• multicollinearity
• prediction equation