Four weaned female goats, with an initial body weight of 8 kg and 4-5 months of age, were assigned to 4 treatments in a 2*2 factorial design in a 4*4 Latin square. The treatments were: foliages of Gliricidia or Mimosa and potassium nitrate or urea as the source of NPN.
DM intake was higher for Mimosa than Gliricidia but was not affected by NPN source. Coefficients of apparent digestibility of OM and crude protein, and N retention were higher for Mimosa than Gliricidia but were not affected by NPN source. N retention as percent of N digested did not differ between the two foliages, implying that digestibility of the crude protein rather than its biological value, was the reason for the superiority of the Mimosa as a feed for goats. The ratios of concentrations of methane to carbon dioxide in the mixed eructed gas and air were decreased by replacing urea with potassium nitrate; the reduction in methane mission due to nitrate was 40 % compared with urea.
Key words: Digestibility , intake, NPN, N retention, potassium nitrate, urea