RESUMO
Pornunça (Manihot sp.) is a potential forage to feed ruminants in drylands worldwide; however, evaluations of animal diets are necessary. This study assessed intake and digestibility of dry matter and nutrients, physiological responses, ingestive behavior, water intake, as well as hematological and biochemical responses of lambs fed diets containing increasing levels of Pornunça silage (PS) replacing Tifton-85 bermudagrass hay (Cynodon spp.). Treatments consisted of 0, 33, 66, and 100 % PS considering the roughage portion of the diet (% dry matter - DM). The experimental design was completely randomized with six replicates. Cyanide acid (HCN) levels in fresh Pornunça leaves were 207.7 mg kg-¹ DM and 76.78 mg kg-¹ DM in PS. Intake of DM and crude protein (CP), and neutral detergent fiber corrected for ash and protein (NDFap) increased linearly with increasing levels of PS in the diet. Digestibility of DM, NDF, and CP were higher with increasing levels of PS. Idle time decreased linearly, while water balance, water intake via food, and total water in feces increased with PS. Nitrogen balance, physiological, and hematological responses were not influenced by treatments, while the final alanine aminotransferase increased for lambs fed all diets evaluated. The PS up to 100 % of the roughage portion increased DM and nutrient intake and digestibility without altering physiological responses and the hematological and biochemical parameters, resulting in greater water intake via food.
Assuntos
Animais , Masculino , Ovinos/fisiologia , Ovinos/sangue , Manihot , Dieta/veterinária , Fenômenos Fisiológicos da Nutrição AnimalRESUMO
The objective of this study was to evaluate the potential of mesquite bean flour (Prosopis juliflora) as an energy ingredient in extruded diets for juvenile Nile tilapia (Oreochromis niloticus). Two experiments were carried out: the first consisted of a study to evaluate the chemical composition and digestibility of the energy and nutrients of MBF; the second consisted of a growth test, in which juveniles consumed diets containing different proportions of corn substitution by MBF, in which zootechnical, hematological, physiological, and metabolic variables were evaluated. It was observed that MBF has a chemical composition similar to corn, as well as the apparent digestibility of energy and nutrients. The higher sucrose/starch ratio of the ingredient stands out, as well as the difference in digestibility (p < 0.05) between the predominant carbohydrates 87.63 and 99.25% for starch and sucrose, respectively. In the growth assay, no difference was observed between zootechnical variables (p > 0.05), and sucrase and alkaline phosphatase activities were increased (p < 0.05), which was not observed for amylase and lipase (p > 0.05). The hematological variables did not change (p > 0.05). Metabolic variables indicate a reduction in gluconeogenesis from amino acids, as can be seen by the reduction in liver transaminase levels (ALT and AST) and glutamate dehydrogenase (GDH), as well as the greater availability of free amino acids in plasmas (p < 0.05). Thus, it can be said that MBF has a high nutritional value and can totally replace corn in diets for juvenile tilapia and the metabolic findings indicate a potential protein-sparing effect.