Production and composition of milk from Bergamasca breed ewes supplemented with linseed oil (Linum usitatissimum L)

Abstract

The conjugated linoleic acid (CLA) is excellent to human health and according several researchers it presents a nutraceutical effect, acting as an anti-carcinogenic. This acid can be formed in the rumen through incomplete biohydrogenation of polyunsaturated fatty acids provided in animal feeding such as linseed. Most of oilseeds have the conjugated linoleic acid, but the linseed is an exception, because it presents a high content of fatty acid linoleic. However there are few researches on the addition of linolenic acid in the diet of milk ewes and on its effect on their milk, which becomes even more beneficial to humans. Therefore, the objective of this study is to asses the production responses of Bergamasca ewes in lactation. They are going to be given linseed oil on Panicum maximum cv. Tanzania pasture. The experiment will be carried at Ewe Milk Production and Research Unit, University of Veterinary Medicine and Animal, UNESP, Botucatu Campus, SP state, with 48 Bergamasca ewes, which are approximately 2.5 and 3.5 years old. These will be distributed into two types of treatments: A) ewe supply with concentrate, with 3% of linseed oil and B) ewe supply with concentrate, without linseed oil. Both treatments will be balanced according to NRC (1985) for lactating ewes. The following variables will be evaluated: body weight dynamics, total milk production and its proximate composition, milk and cheese fatty acid composition and cheese sensory aspects and lambs performance.