Mare milk at drying-off: chimico-physical characteristics, nitrogen composition and mineral elements in Italian Saddle and Haflinger nursing mares

Nursing mares milk characteristics at drying-off (D) were investigated; comparison was made with milk taken during early lactation (3÷30 d post partum) (E). The survey was carried out in 17 Italian Saddle (IS) (193 DIM; 147 pregnancy days) and 12 Haflinger (H) (174 DIM; 146 pregnancy days) mares. N fractions were determined according to Aschaffenburg and Drewry; fat and lactose by IR; mineral elements were determined by AAS; P by colorimetry. Data referred to 58 individual milk samples were analysed by ANOVA. Significant variations, with similar trends in both breeds, were observed (E vs D) for density at 15°C (1.036 vs 1.034), pH (6.94 vs 7.24), titratable acidity (3.59 vs 1.71 °SH), fat (1.17 vs 0.77%), crude protein (2.32 vs 1.69%), ash (0.503 vs 0.306%), Ca (0.113 vs 0.055%), P (0.061 vs 0.033%); similarly (mg/100g) for noncasein N (170.8 vs 140.4), nonprotein N (34.4 vs 29.0), Mg (8.5 vs 4.5) and K (61.0 vs 41.5). Freezing point, lactose and Na showed no significant variations. At drying-off milk resulted poorer in all main organic components, except lactose, and in all mineral components, except Na. Only freezing point and Mg trends differed in IS from H. Breed affected significantly fat, ash, P and Ca mean contents.