Abstract 18

Alhassan,WS; Aliyu,-SU

National Animal Production Research Institute, Ahmadu Bello University, Zaria, Nigeria.

Animal-Feed-Science-and-Technology. 1991, 33: 3-4, 289-295; 13 ref.

Chopped maize straw was treated with urea 0, 20, 40, 60 or 80 g dissolved in water 500 ml per kg straw and ensiled in laboratory silos for 1, 3, 5 or 7 weeks. DM disappearance of straw in the rumen was estimated by nylon bag incubation in vivo. The lowest urea concentration and shortest ensilage period which gave maximum DM disappearance was urea 40 g/kg straw (4% urea concentration) ensiled for 1 week. In a 2 X 2 factorial trial, 24 White Fulani zebu cattle, 145 kg, were fed for 90 days on diets containing untreated straw or straw treated with 4% urea and ensiled for 1 week without or with groundnut haulms 1.5 kg/day. Crude protein content of treated straw was 8.4% compared with 4.8% for untreated straw. Organic matter digestibility was 65.3% for treated and 51.0% for untreated straw. Urea treatment and supplementation with groundnut haulms increased straw intake, but did not prevent cattle weight loss. There was no significant treatment effect on cattle weight changes, although there were trends favouring such treatments.