Phenotypic relationships between udder and milking characteristics, milk production and California mastitis test in goats

Abstract

Data of crossbreed goats (28 Alpine × criolla; 6 Granadina × criolla; 13 Nubian × criolla) kept on natural pasture at Irapuato, México, and hand-milked once a day, were studied for daily milk production (MP), milking time (MT), California mastitis test score (CMT), udder perimeter (UP), teat perimeter (TP), teat length (TL), udder cleft (UC), udder shape (US), teat shape (TS) and teat end shape (TE). UP, TP, TL and UC were measured before milking. Kids were separated from their mothers for a 24-h period prior to milking. Milking rate (MR) was MP/MT. MP ( r=−0.32) and UP ( r=−0.33) were correlated with CMT ( P<0.05). UP had r=0.81 ( P<0.01), and TP had r=0.45 ( P<0.05) with MP. Goats with globular udders had significantly lower values ( P<0.05) for CMT, and higher ( P<0.05) for MR and MP than goats with non-globular udders. Goats with non-balloon teat shape had significantly lower ( P<0.05) CMT values than those with balloon-shaped teats. Results suggest that goats with globular udders and non-balloon-shaped teats have greater resistance to mastitis. UP and TP had greater correlations with MP than other morphological variables.