This study aimed to evaluate the quality of leucaena, gliricidia, and pornunça silages with different levels of old man saltbush inclusion in their composition. A completely randomized design was used with five levels of old man saltbush (Atriplex nummularia) inclusion (0, 25, 50, 75, and 100%) in leucaena (Leucaena leucocephala), gliricidia (Gliricidia sepium), and pornunça (Manihot sp.) silages, with 5 replications per treatment, totaling 75 experimental mini-silos maintained in a covered shed and free of opportunistic animals. Silos were opened after 100 days of ensilage, and the silage of the first 15 cm of their ends was discarded. The remaining material was homogenized and sampled for determining the bromatological composition, in vitro digestibility, and fermentation profile. Old man saltbush inclusion levels in leucaena silages promoted a negative linear effect for dry matter, organic matter, crude protein, ethereal extract, pH, and ammoniacal nitrogen, while a positive linear effect was found for mineral matter, in vitro dry matter digestibility, total carbohydrates, non-fibrous carbohydrates, and propionic acid (P < 0.05). This silage also had a quadratic effect for lactic acid. Gliricidia silages showed a positive linear behavior for dry matter, mineral matter, and total carbohydrates, whereas organic matter, crude protein, and ethereal extract presented a negative linear behavior (P < 0.05). The contents of organic lactic, acetic, and propionic acids showed a quadratic effect for gliricidia silage as old man saltbush levels increased (P < 0.05). Regarding pornunça silage, dry matter, mineral matter, total carbohydrates, propionic acid, and butyric acid presented a linear increasing behavior, while organic matter, crude protein, ethereal extract, and non-fibrous carbohydrates presented a linear decreasing behavior (P < 0.05). Lactic acid and acetic acid concentrations for pornunça silage showed a quadratic behavior according to the increasing old man saltbush inclusion levels (P < 0.05). The highest contribution of old man saltbush in the silages promoted changes in the profile of organic acids, allowing an improvement in silage quality, favoring lactic fermentation rather than acetic fermentation. Butyric acid contents were low for all treatments and indicated the control of undesirable fermentation processes. These results indicate that old man saltbush inclusion in silage composition may contribute to bromatological composition and fermentation process of the studied silages.

Objetivou-se no presente estudo determinar o consumo, digestibilidade aparente da matéria seca e nutrientes, além dos balanços de nitrogênio (BN) e hídrico (BH), de ovinos alimentados com silagens de capim-búfel. As silagens das cultivares de capim-búfel avaliadas foram Tanzânia, Buchuma e Biloela. Utilizaram-se 21 ovinos, machos, castrados, mestiços Santa Inês x Sem Padrão de Raça Definido, com peso corporal médio inicial de 31,8±3,16kg, mantidos em gaiolas metabólicas. Foi utilizado um delineamento inteiramente casualizado com sete repetições. Não foram observadas diferenças nos consumos de MS em g/dia (919,2) e porcentagem do peso corporal (2,9). De modo geral, os coeficientes de digestibilidade da matéria seca variaram de 37,7% a 60,0%. Os BN e BH foram positivos, sendo observados maiores valores de BN para os ovinos alimentados com silagens de capim-búfel dos cultivares Tanzânia (5,1g/dia) e Biloela (3,9g/dia), e maiores BH para os animais alimentados com silagens de capim-búfel dos cultivares Buchuma (1,38kg/animal/dia) e Biloela (1,42kg/animal/dia). Os cultivares de capim-búfel Tanzânia, Buchuma e Biloela apresentaram bom valor nutritivo, sendo que o capim-búfel na forma de silagem promoveu 60% do consumo total de água diário do animal.