BODY COMPOSITION AS A FUNCTION OF COAT COLOR, SEX AND AGE IN LOCAL KIDS FROM NORTHERN MEXICO

Abstract

The aim was to evaluate the effect of coat color, sex and age on body composition in local kids from northern Mexico. Eighty-three local kids between 1 and 30 days of age were selected. They were assigned to groups according to coat color (dark and light), sex (males and females) and age (1=1 to 10; 2=11 to 20 and 3=21 to 30 days). Pigmentation of skin, hooves, mucous membranes, morphostructural characteristics, live weight and 14 zoomometric measurements were evaluated. A predominant phenotype was found of animals without mammels, beards, without pigment in the skin and hooves, with horns, horizontal ears and pigmented mucous membranes. The highest values (p < 0.05) for live weight (PV), neck length and width (LCue, ACue), chest circumference (CPe) and flank depth (PFl) were found in dark kids. The highest value (p < 0.05) in ear length (LO) was observed in light-colored kids. When considering sex, the highest values (p < 0.05) were observed in males for all traits, except for length and width of face (LCa, ACa) and width of ears (AO), height at withers (ACruz), PFl and sacrolumbar height (ASL), which were not different (p > 0.05). When considering age, the highest values were found in all traits for group 3. All variables were positively and significantly correlated. The variables showing the greatest magnitude of change in the first 20 days of age are PV (+40 %), LCa, LCor, CPe (+15 %) and LCue, ACruz, PFl, leg length (+10 %), while between 20 and 30 days of age the magnitude of change generally decreases. It is concluded that coat color, sex and age significantly influence the body composition of local kids from northern Mexico, which may have implications in the selection and marketing thereof.