Abstract:
Proc. Aust. Soc. Anim. Prod. Vol. 17 FATTY ACID CALCIUM SOAPS AS SUPPLEMENTS FOR GRAZING DAIRY COWS G.L. ROGERS and I.B. ROBINSON 459 The inclusion of Megalac* (a mixture of calcium acids) in the ration of grain-fed dairy cows has been yield (Robb abd Chalupa 1987). The high rumen pH of improve the resistance of fatty acid calcium salts to (Palmquist 1984). In this experiment we examined the supplement for grazing dairy cows. salts of Cl6 - Cl8 fatty reported to increase milk grazing dairy cows would rumen degradation use of Megalac as a Three groups of ten dairy cows in mid lactation grazing perennial ryegrass/white clover pasture were supplemented with either nil, 4 kg commercial pellets or 4 kg commercial pellet fortified with 144 g/kg of Megalac. Digestible dry matter (%), crude protein (%> and gross energy (MJ/kg) were 80, 18.1 and 18.3; 68, 16.9 and 17.5; 63, 16.9 and 20.5 for pasture, pellets and Megalac fortified pellets. Supplements were offered for one month and measurements made over the last 2 weeks are shown in Table 1. Table 1. Effects of addition of calcium salts of long chain fatty acids on milk yield and composition The poor response in milk yield of cows fed commercial pellets suggests that total food intake was not increased and less pasture was eaten. Cows fed Megalac pellets increased milk yield by 1.2 L/cow/day (P < 0.05). Assuming that the fatty acids were protected from rumen degradation and 95% absorbed in the lower gut, the significant increase in milk yield can be explained by the higher energy intake supplied by the Megalac pellets (82 mJ/cow/day vs 70 mJ/cow/day). PALMQUIST, D.L. (1984). Can. J. Anim. Sci. 64 Guppl.) : 240. ROBB E.J. and CHALUPA, W. (1987). J. Dairy Sci. 70 (Suppl. 1) : 219. Dairy Research Institute, Ellinbank, R.M.B. 2460, Karragul, Vic., 3820 * Megalac. A registered product of Volac Pty. Ltd., U.K.