This study aimed at examining the effects of rumen inoculum of steers receiving different combinations of ionophore and probiotics in their diets on in vitro gas production of corn silage. The fitting of gas production was performed with five mathematical models and its kinetics was evaluated. Four crossbred steers (403.0 ± 75.5 kg body weight) with ruminal cannula were assigned to a 4 × 4 Latin square design. The additives used were Monensin sodium (Rumensin^® 100, 3 g/day), Bacillus toyonensis (Micro-Cell Platinum^® 10⁹, 1 g/day) and Saccharomyces cerevisiae boulardii (ProTernative^®20, 0.5 g/day). Additives were arranged into the following treatments, supplied daily into total mixed diet: (1) Monensin; (2) Monensin + B. toyonensis; (3) Monensin + S. boulardii; and (4) B. toyonensis + S. boulardii. The gas production data were fitted into the models of Gompertz, Groot, Ørskov, Brody, Richards, and Dual-pool Logistic. A perfect agreement between observed and predicted values in curves of accumulated in vitro gas production was observed in the Groot and Richards models, with higher coefficient of determination (R² = 0.770 and 0.771, respectively), concordance correlation coefficient (CCC = 0.871 and 0.870, respectively), and root mean square error of prediction (RMSEP = 1.14 and 1.15, respectively). Evaluating the feed additives throughout the Groot model, the B. toyonensis + S. boulardii treatment presented higher V_F (12.08 mL/100 mg of DM; p = 0.0022) than Monensin and Monensin + S. boulardii (9.16 and 9.22 mL/100 mg of DM, respectively). In addition, the fractional rate of gas production (k) was higher (p = 0.0193) in B. toyonensis + S. boulardii than in Monensin, not presenting a statistical difference (p > 0.05) from the other two treatments. Additionally, with the time of beginning to gas production, the lag time (λ), was greater (p < 0.001) with Monensin and Monensin + B. toyonensis than with Monensin + S. boulardii and B. toyonensis + S. boulardii. The combination of Monensin and probiotics (B. toyonensis + S. boulardii) resulted in better kinetics of degradation of corn silage, being that the Groot and Richards models had the best fit for estimates of the in vitro gas production data of corn silage tested with different feed additive combinations.

Inclusion of concentrate and growth promoters additives in sheep diets on intake, digestibility, degradability, ruminal variables and nitrogen balance

It was hypothesized that it is possible that inoculum from different ruminant species with different digestive abilities feeding from a certain forage may show different feed utilizations comparing to other ruminant species. Five Brachiaria grasses were evaluated: B. decumbens cv. Basilisk, B. decumbens access D70, B. humidicola cv. Tupi, B. humidicola cv. Common, and B. ruziziensis access R124, at two regrowth ages (21 and 42 d). Production, bromatological content, in vitro dry matter digestibility (ivDMD) and in vitro neutral detergent fiber digestibility (ivNDFD) were analyzed using bovine or ovine inoculums. The experiment used a 5 × 2 × 2 factorial design and found significant effects for grass variety and regrowth age. In addition, significant interactions from grass × age on dry matter, crude protein, neutral detergent fiber and acid detergent fiber of total sample and leaf blade were found. There were significant effect of grass variety and grass age on forage mass, leaf blade/stem ratio, leaf blade, stem, senescent material and growth. In vitro digestibility assays of inoculum source showed significant effect in some varieties. Due to differences in in vitro assays, it was recommended the use of species-specific inoculums for feed evaluations according to the animal it is intended for. Also, B. decumbens cv. Basilisk presented the best in vitro digestibility (ivDMD and ivNDFD) in bovine inoculum, whereas B. humidicola cv. Tupi had better in vitro digestibility (ivDMD and ivNDFD) in ovine inoculum.

The objective of this study was to evaluate the effects of injectable trace minerals (ITM) on growth, health, antioxidant enzyme activity, and immune system of newborn Boer kids. Newborn kids (n = 125) were assigned to one of two treatments: injection (0.1 mL 4.5 kg-1) of saline or ITM. Injectable trace minerals had 60, 10, 5, and 15 mg mL-1 of Zn, Mn, Se, and Cu, respectively. Kids were evaluated daily for the presence of diarrhea and weighted on [...] ABSTRACT The objective of this study was to evaluate the effects of injectable trace minerals (ITM) on growth, health, antioxidant enzyme activity, and immune system of newborn Boer kids. Newborn kids (n = 125) were assigned to one of two treatments: injection (0.1 mL 4.5 kg-1) of saline or ITM. Injectable trace minerals had 60, 10, 5, and 15 mg mL-1 of Zn, Mn, Se, and Cu, respectively. Kids were evaluated daily for the presence of diarrhea and weighted on