Effect of Fishmeal Supplementation on Milk Yield of Holstein-Friesian Cows in Eritrea

Abstract

A feeding experiment was carried out to determine the effect of supplementing the existing diet for dairy cows on a semi-government owned farm in Eritrea (Elabered Estate), with varying amounts of fishmeal that was locally produced by sun-drying and grinding. The experiment consisted of a two-week pre-experimental period followed by 90 days of experimental period. Forty primiparous Holstein cows, which had been milking for an average of 77 days, were placed into four groups of 10 each Group I to IV). The basal diet consisted of fresh alfalfa, grass hay, fodder maize, wheat middlings, wheat bran and wet brewer's grains to make23.2,19.9,14.9,15.8,15.4 and 10.8% by weight on dry matter basis. This diet was offered throughout the experiment to cows in Group IVas the control diet and to all groups in the pre-experimental period. Cows in Groups I, II, and III received the same basal diet supplemented with 100, 200' and 300 g of fishmeal, respectively, in the experimental period. The cows were fed in a restricted manner. Crude protein (CP), crude fiber (CF), ether extract (EE), Ca, and P, given as % of dry matter, and ME (MJ/kg dry matter) of the control diet was 13.7, 23.1,2.7, 0.62, 0.47 and 9.72, respectively. With fishmeal supplementation, the CP content of the diets fed to cows in Groups I, II, and III increased to 14.0, 14.2 and 14.5%, respectively. Milk yield of cows after adjusting for the pre-experimental milk yield were 13.84, 13.32, 13.29 and 12.98 kg/day for cows in Groups I, II, III and IV, respectively. Supplementation with 100 g of fishmeal per cow per day resulted in the highest milk yield compared to the control (P=0.055). The 200 and 300 g of fishmeal supplementation did not increase the milk yield further, possibly due to the high protein content of the control diet.

Keywords: Dairy cows, fishmeal, supplementation, milk yield

Tanzania J. Agric.Sc. (2007) Vol. 8 No.1, 39 - 50