Evaluation <em>in situ</em> of <em>Brachiaria decumbens</em> Stapf cv. Basilisk hay submitted to treatment with anydhrous ammonia or urea

Abstract

Brachiaria decumbens Stapf cv. Basilisk hay ammoniation effects were evaluated at Unesp, Câmpus de Jaboticabal, state of São Paulo, Brazil, after harvesting at seed maturation stage and submitted to the following treatments: untreated and treated with NH₃ (2.0% and 3.0% DM) or with urea (3.6% and 5.4% DM), using in situ technique with incubation bags in the rumen of fistulated animals. The experiment was conducted in split-plot randomized blocks with 3 replications. Ammoniation increased (P < 0.05) DM, OM, CP and NDF consumption rates in 6, 24 and 96-hour incubation period, but it did not affect hay degradation rates. The treatment with NH₃ increased (P < 0.05) DM, OM and NDF degradation potential. The highest CP effective degradation was caused by 5.4% urea level, and the results of this investigation led to the conclusion that NH3 may be replaced by urea and that the inclusion of 5.4% of urea is the most appropriate to Brachiaria decumbens hay treatment in advanced maturation stages.