Fat addition in the diet of dairy ruminants and its effects on productive parameters

Abstract

This review analyzes the current knowledge on the effects of fat supplementation in dairy ruminant diets. Research conducted on dairy cows and goats shows that dry matter intake decreases when diets contain extra fat due to a negative effect on digestibility. In dairy cows dry matter intake can be also decreased by gut peptides released in response to extra fat. This effect has not been observed in ewes and goats. Milk yield increases in dairy cows, ewes, and goats in a curvilinear manner with increasing amounts of dietary fat. When fat supply is low, the increase in milk yield is probably caused by a higher energy intake. However, milk yield decreases when fat supply is high, which may be related to diminished energy availability for milk production due to negative effects on rumen digestion and/or dry matter intake. Unprotected lipids negatively impact milk fat content in dairy cows, but not in dairy ewes and goats; negative effects of supplemental lipids on milk protein content observed in dairy cows and ewes has not been observed in dairy goats.

Keywords

• consumo voluntario
• digestibilidad
• leche
• lípidos