Nutritional strategies, performance, digestibility, and carcass traits of Santa Ines and Rabo Largo breeds in a tropical climate.

The aim of this study was to compare the performance, intake, digestibility, ruminal parameters, carcass traits, and the yield of commercial cuts of Santa Ines (SI) and Rabo Largo (RL) breeds fed diets with high or low roughage-to-concentrate ratio (R:C) under a tropical climate. Twenty lambs from each breed were individually housed in covered pens and fed the experimental diets for 58 days. The diets were formulated to meet the growth requirements of lambs with a roughage-to-concentrate ratio of 70:30 and 30:70. Significant interactions of breed × diet for nutrient intake were observed (P < 0.05), with SI lambs fed low R:C diet showing higher intake of dry matter, organic matter, crude protein, and total carbohydrates compared to RL lambs fed the same diet. SI lambs fed high R:C diet had higher intake of neutral detergent fiber than RL lambs (P < 0.05). SI lambs displayed better average daily gain and feed efficiency, regardless of diet (P < 0.05). Carcass traits and gastrointestinal components were influenced by breed and diet (P < 0.05). SI lambs fed low R:C diet showed higher subcutaneous fat thickness and better carcass finishing compared to RL lambs (P < 0.05). SI breed lambs exhibited better growth performance, carcass traits, and gastrointestinal characteristics, even when fed diets with a high roughage-to-concentrate ratio.

Nutritional effects and feeding behavior in ewes fed with biscuit bran and cashew nut bran, with different energy levels.

This research evaluated the effects of biscuit bran and cashew nut bran as energy source and additional energy level on intake, digestibility, feeding behavior, energy partitioning, N balance, and blood parameters on ewes. Twenty Morada Nova cull ewes breed (average age of 3 years old and initial body weight of 30.1 ± 3.56 kg) were distributed in a completely randomized design in a 2 × 2 factorial scheme of two energy sources (biscuit bran vs. cashew nut bran) and two levels of energy above 10% and 25% of the recommended energy requirements. The inclusion of cashew nut bran above 10% of the recommended energy promoted a lower crude protein (CP) and ethereal extract intake (P < 0.01) than cashew nut bran above 25% of the recommended energy. The interaction between energy source × energy level did not affect digestibility and energy partition on ewes (P > 0.05). The diet containing cashew nut bran above 10% of the recommended energy presented lower metabolizable energy intake and energy balance (P < 0.05). Regarding N balance, the cashew nut bran diet above 10% of the recommended energy decreased Nintake (P = 0.01), Nabsorbed (P < 0.01), and Nbalance (P = 0.04). Partial replacement of corn with the byproduct biscuit bran or cashew nut bran is a possible nutritional strategy. Ewes fed with 210 g/kg of biscuit bran presented greater CP intake and improvement of the protein use with the reduction of plasma levels of urea.

Fermentative profile, losses and chemical composition of silage soybean genotypes amended with sugarcane levels.

The experiment aimed to evaluate the fermentative and nutritional profile of the silage of four soybean plant genotypes (BRS 333 RR, Pampeanas: C50, C60, and C70) ensiled with levels of sugarcane (0, 25, 50, 75, and 100%). The experiments were conducted in a completely randomized design, in factorial scheme 4 × 5 (four soybean genotypes and five levels of sugarcane inclusion) with four replicates. Silages with 100% soybean plant presented the highest levels of butyric acid (P < 0.001) and ammoniacal nitrogen (P < 0.047); however, the intermediate addition of sugarcane contributed to lactic fermentation (P < 0.001). Besides, there was a quadratic effect (P < 0.05) for the recovery of dry matter, which ranged from 83.28 to 95.29%, with higher values observed for silage with the same proportions of soybean plant and sugarcane. It was verified that the crude protein content exhibited decreasing linear effects (P < 0.001), varying among 4.60 to 7.48% in the silages. It was concluded that the highest recovery of dry matter, the best fermentation profile, and the highest levels of crude protein and digestibility occurred in the inclusion between 25 and 50% of sugarcane in soybean silage, with the superiority of the C50 soybean genotype.