The research was conducted to evaluate two sources of ammonia (anhydrous ammonia-NH3 or urea) to preserve alfalfa (Medicago sativa L.) hay stored with high moisture. The following treatments were studied: A - Control: untreated hay (12 to 15% moisture); B - hay (24 to 27% moisture) treated with NH3 (1.0% of DM); C - hay (24 to 27% moisture) treated with urea (0.9% DM); D - hay (24 to 27% moisture) treated with urea (1.8% DM); E - hay (34 to 37% moisture) treated with urea (0.9% DM) and F - hay (34 to 37% moisture) treated with urea (1.8% DM). The hays remained under plastic sheet during 60 days. After this time the stack was opened and sampled to identified the fungus genus (0 and 60 days). Chemical composition was determined in relation to the crude protein (CP) and cell wall contents. The NH3 treatment was efficient to control the fungi, except Paecilomyces. The urea application controlled the Aspergillus and Penicillium incidence. The others fungi caused forage deterioration on the high moisture hay treated with urea. The NH3 treatment did not affect the chemical composition of the hay, except the CP content increased in the hay treated with NH3.
additive; anhydrous ammonia; chemical composition; fungi; urea
