Perfil de ácidos graxos no leite de vacas holandês em pastagens tropicais suplementadas com dois níveis de concentrado / Milk fatty acids profile of Holstein cows grazing tropical forages supplemented with two concentrate levels

ABSTRACT

Milk fatty acids profile was evaluated using 12 Holstein cows producing 15 kg/day of milk with 4.0% of fat. The animals were assigned to four treatments in a 2 x 2 factorial arrangement (two tropical grasses - Brachiaria brizantha cv. Xaraés and Panicum maximum cv. Tanzania, supplemented with two concentrate levels - 3 and 6 kg/cow/day) in a completely randomized block design. There was no effect of forage and concentrate level (P>0.05) on concentrations of rumenic, vaccenic, (C18 1 trans-11) and oleic acids in milk fat (mean values of 1.01, 1.79, and 22.55 g/100 g of total fatty acids, respectively). The concentrations of lauric (C120), myristic (C140), and palmitic (C160) acids were also unaffected by treatments (mean values of 2.63, 9.77, and 27.44g/100g of total fatty acids, respectively). Overall, the results illustrate the potential of tropical grasses in producing milk containing a more desirable fatty acids profile in terms of human health.