ABSTRACT Coconut meal can be an affordable low-cost alternative to noble ingredients such as corn and soybean meal in sheep diets. The objective of this study was to evaluate the effects of coconut meal inclusions, when used as a corn and soybean meal replacement, on the intake, digestibility, and nitrogen balance of sheep diets. Twenty-four male Santa Inês lambs with body weights (BW) of 26.6 ± 3.2 kg were used in the study. The animals were housed in metabolic cages and distributed in a completely randomized block design, with three treatments and eight replications. The animals received a total mixed ratio of 30% roughage (elephant grass) and 70% concentrate. The animals were fed on two experimental diets with 11% and 22% coconut meal inclusion and a control diet (without coconut meal). Dry matter (DM), crude protein (CP), neutral detergent fiber (NDF), acid detergent fiber (ADF), and non-fibrous carbohydrate (NFC) intake as a percentage of BW were negatively influenced by the inclusion of coconut meal. The ether extract (EE) intake increased but did not differ between the 11% and 22% coconut meal diets. Furthermore, the digestibility of DM, CP, EE, and ADF did not differ between the two evaluated diets. The inclusion of coconut meal reduced NDF digestibility and increased that of NFC. The level of inclusion of coconut meal in the diet must be based on the EE content in the meal; keeping the EE intake below 0.16% of the BW helped to avoid limited intake of feed.

RESUMO A torta de coco pode ser uma alternativa disponível e de baixo custo para substituir ingredientes nobres como o milho e o farelo de soja em dietas para ovinos. Objetivou-se com esse estudo, avaliar a inclusão de torta de coco em substituição ao milho e o farelo de soja em dietas para ovinos sobre o consumo, a digestibilidade aparente dos nutrientes e balanço de nitrogênio. Foram utilizados 24 cordeiros machos da raça Santa Inês, com peso corporal (PC) de 26,6 ± 3,2 kg, mantidos em gaiolas metabólicas, distribuídos em delineamento em blocos casualizados, com três tratamentos e oito repetições. Os animais receberam ração total com 30% de volumoso (capim elefante) e 70% de concentrado. Foram testadas uma dieta controle (sem torta) e outras duas, com 11 e 22% de inclusão da torta de coco. Os consumos de matéria seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA) e carboidratos não fibrosos (CNF) em % do PC foram influenciados negativamente pela adição da torta de coco. O consumo de extrato etéreo (EE) aumentou, sem diferença entre dietas com 11 e 22%. A digestibilidade da MS, PB, EE e FDA não diferiram entre as dietas avaliadas. A inclusão da torta reduziu a digestibilidade da FDN e aumentou a dos CNF. O nível de inclusão da torta de coco na dieta deve estar relacionado ao teor de extrato etéreo da torta, mantendo o consumo de EE abaixo de 0,16% do peso corporal para não limitar a ingestão.

ABSTRACT In this study, we aimed to determine the effects of cutting height (25 or 40 cm above ground) and bacterial inoculation (a combined inoculant of Lactobacillus plantarum and Propionibacterium acidipropionici) on the chemical and microbial compositions, fermentative profile, and aerobic stability of whole-plant corn silage and nitrogen balance, intake, and apparent nutrient digestibility by sheep. To evaluate silage characteristics and sheep metabolism, we performed analyses based on a completely randomized block design with a 2×2 factorial arrangement (two cutting heights, with or without bacterial inoculant). We evaluated the chemical and microbial compositions, pH, fermentation end-products, and aerobic stability of silage. To examine nutrient digestibility of silage, we used 24 male sheep over a 21-day period. We found that the aerobic stability did not differ among the silages. Sheep fed silages produced from corn harvested at 40 cm had increased intakes of crude protein, non-fiber carbohydrate, and total digestible nutrients, whereas the non-fiber carbohydrate intake of inoculated corn silages was found to be higher than that of uninoculated silage. Furthermore, the amounts of nitrogen retained by sheep fed silage produced from corn harvested at 40 cm were higher than those of sheep fed silage produced from corn harvested at 25 cm. Collectively, our findings indicate that, despite the observed effects, a difference of 15 cm in cutting height results in relatively small changes in the chemical composition of corn silage and a limited effect on the nutrient intake and nitrogen balance of animals fed this silage. Moreover, although bacterial inoculation promotes an efficient fermentation, it has no marked effects on the aerobic stability of silage.