PRODUCTION AND MILK FATTY ACIDS PROFILE OF DAIRY GOATS FED WITH CANOLA SILAGE (Brassica napus) INSTEAD OF CORN SILAGE (Zea mays) IN TOTAL MIXED RATIONS

Abstract

Background. Canola silage (EC) is a viable alternative to replace corn silage (EM) in ruminants feed, due to its nutritional value and source of polyunsaturated fatty acids to improve the quality milk fat. Objective. To evaluate the inclusion of EC as substitute for of EM in total mixed rations (TMR) on milk production, composition and fatty acids profile of goats at the end lactation. Methodology. Ten Alpine goats (49 ± 2.5 kg LW, 194 ± 18 days in lactation) were fed with completely mixed diets containing 25% EC plus 25% EM (experimental diet) and 50% EM (control diet). Results. Milk production in goats fed with EC was 33.46% higher (P<0.05) than in goats eating only ME as forage. The content of rumenic and vaccenic acids in milk increased (P<0.05) 60 and 57%, respectively, with the inclusion of EC in the diet. There were not differences (P>0.05) in milk fat, protein and lactose content, nor in dry matter intake between treatments. Implications. EC as an alternative forage in combination with EM, it is a viable feeding strategy for small ruminants. Conclusions. The use of EC represents a feeding strategy to improve the fatty acid profile of milk without effecting the chemical composition of milk and the productive response of goats at the end of lactation.