NONGENETIC EFFECTS ON MILK-PRODUCTION OF LATXA EWES

Effects of parity, lambing season, lactation length and interval of la mbing to first recording of milk production of Latxa milking ewes were analyzed. One thousand records collected between 1983 and 1986 in the Basque Country (Spain) were studied. Milk yield averaged 138 (+/-47) kg (CV = 34%) with 5.77 (+/-0.80) % fat (CV = 14%) and 5.07 (+/-0.41 ) % protein (CV = 8%). Negative correlation coefficients between milk y ield and fat% (-0.27) and milk yield and protein% (-0.24) were found. Multiple correlations (R2) for the combined effects of parity, season, lactation length and record intervals on milk, fat and protein yields were 0.33, 0.39 and 0.44, respectively; while for fat% and protein% t hey were 0.19 and 0.33, respectively. Lambing season and lactation len gth were the most important effects (P less-than-or-equal-to 0.001 for all variables) on milk yield. Parity was highly significant (P less-t han-or-equal-to 0.01) for milk, fat yields and protein%, but not signi ficant for fat% and protein yield. The lambing to lst recording interv al was highly significant (P less-than-or-equal-to 0.01) only for prot ein%.