Effect Of Supplemental Feeding Of Rumen Protected Conjugated Linoleic Acid On An Intermittent Basis To Dairy Cows PDF Download

Recently, there has been considerable interest in the potential health-promoting properties of conjugated linoleic acid (cis-9, trans-11 CLA), a fatty acid produced naturally in ruminant animals, and omega-3 fatty acids. The primary objective of this trail was to determine the effects of varying levels of linseed oil (LSO) on grazing dairy cows' diet on milk cis-9, trans-11 CLA and omega-3 fatty acids content. Twelve Holsteins cows in mid lactation (150 ± 19 Days in milk) were placed on alfalfa based pasture and assigned into four treatment diets using a 4X4 Latin square design with 3 wk period. Treatment diets were: (1) control grain supplement (CONT); (2) control grain supplement containing 170g LSO (LSO1); (3) control grain supplement containing 340g LSO (LSO2) and (4) control grain supplement containing 510g LSO (LSO3). Grain supplements were offered at 7 kg/d twice daily. Additional 100 g/d of algae, divided evenly between the two feeding times, were added to every treatment diet. Milk samples were collected during the last three days of each period and analyzed for chemical and fatty acids composition. Treatment diets had no effect on milk production (18.93, 18.50, 19.60 and 19.10 kg/d for treatment diets 1 to 4, respectively), milk fat percentages (3.23, 3.44, 3.35 and 3.27) and milk protein percentages (3.03, 3.19, 3.12 and 3.08). Milk cis-9, trans-11 CLA (1.12, 1.18, 1.39, and 1.65 g/100g fatty acids for treatment diets 1 to 4, respectively), vaccenic acid (VA, trans-11 C18:1; 3.39, 3.62, 4.25, and 4.89 g/100g fatty acids), and total omega-3 fatty acids (0.86, 1.09, 1.26, and 1.25 g/100g fatty acids) concentrations were linearly increased (P