Abstract:
The objective of this work was to use meta-analysis to study the productive results of ewe and goat fed oil and seed, rich in unsatured fat acid. Twenty-two experiments with ewes (63 treatments) and 21 experiments with goats (76 treatments) were used. Average extra fat intake was 83.6±33.6 g per day in ewes, and 73.4±38.7 g per day in goats. In ewes, extra fat intake did not affect dry matter intake, but increased milk fat yield (from 91.4 to 98.8 g per day) and reduced milk protein content (from 5.41 to 5.24%). There were no differences in the sum of fat and protein contents. In goats, extra fat included in the diet reduced dry matter intake (from 2.13 to 2.08 kg per day), and increased milk fat percentage (from 4.11 to 4.43%) and the sum of fat and protein contents (from 7.41 to 7.76%). The yield responses to the intake of diets enriched with unsaturated fatty acids differ between ewes and goats. However, milk commercial value is not affected because of the absence of negative effects on the sum of fat and protein contents in both species.
Index terms:
unsaturated fatty acids; fat; milk; animal production; protein
