Supplementation of corn stover in the feeding of cattle. 2. Ruminal ammonia concentration and ruminal pH

The experiment was conducted in a 4x4 Latin Square design with eight rumen fistulated Holteins-Zebu crossbred steers weighing 290 kg, to evaluate the effect of the supplementation of corn stover with urea, aerial part cassava hay and cottonseed meal on the ruminal ammonia concentration and pH. The treatments were: (A) corn stover plus urea (basal diet), (B) basal diet plus aerial part cassava hay, as a 20% basis of the dry matter fed (DMF), (C) basal diet plus cottonseed meal, as a 5% basis (DMF), and (D) basal diet plus aerial part cassava hay (20% DMF plus cottonseed meal (5% basis DMF) The ruminal ammonia concentration in the treatments B, C and D were greater than in the treatment A; the treatment B did not differ from treatments C and D; and the ruminal ammonia concentration in the treatments C and D were not different. The major average ruminal ammonia concentration value was observed in the treatment D, with 117.20 mg/L, followed by treatments B, C, A, with 99.17, 90.85, and 70.04 mg/L, respectively. There was no ruminal pH difference among treatments. The average ruminal pH, for all treatments, was 6.8.