Animal feed resources information system

Anzola et al., 1990. Livest. Res. Rural Dev., 2 (3): 1-9

Document reference 
Anzola, H. J. ; Martinez, G. ; Gomez, F. ; Hernandez, Y. ; Huertas, H., 1990. Strategic supplementation of bypass protein and fat to dual purpose cattle in the Colombian tropics during the dry season. Livest. Res. Rural Dev., 2 (3): 1-9

The effect of strategic supplementation with bypass protein and fat to dual purpose cows (1/2 European; 1/2 Zebu) was studied from calving to 188 days of lactation, during the dry and beginning of the wet season in the Colombian tropics. Forty F1 cows of four breeding groups: Normandy x Zebu (N x Z = 14); Brown Swiss x Zebu (BS x Z = 10); Gyr x Holstein (G x H = 7) and Holstein x Zebu (H x Z = 9) grazing Brachiaria decumbens were supplemented with three levels of bypass protein (0, 0.5 and 1 kg dry matter per day) of Cotton Seed Meal (CSM) and a mixture of urea, sulphur and a combined source of protein, starch and oil (0.5 kg dry matter per day of rice polishing, RP); the control group grazed Brachiaria decumbens without supplements. A positive (P<0.05) effect was observed in total and daily milk production due to supplementation. Cows in all treatments lost weight but those given zero CSM had the highest weight losses (-299 g/day) (P<0.05). Calves out of supplemented cows gained faster (P<0.05) and had heavier weaning weights (P<0.05) than calves in the control group. Gyr x Holstein F1 cows had significantly (P<0.05) greater total and daily milk production. Reproductive performance was significantly (P<0.05) better in all supplemented groups compared with the control group (66.7 vs 30% pregnancy rates). Normandy x Zebu and Holstein x Zebu averaged 74.6% pregnancy rate against 34.3% for Brown Swiss x Zebu and Gyr x Holstein cows. In conclusion, supplemented cows showed better total productive performance due to lower weight losses, higher milk production, better pregnancy rate and heavier calves.

Citation key 
Anzola et al., 1990