Soybean molasses increases subcutaneous fat deposition while reducing lipid oxidation in the meat of castrated lambs.

This study aimed to evaluate the effect of including soybean molasses (SM) on performance, blood parameters, carcass traits, meat quality, fatty acid and muscle (longissimus thoracis) transcriptomic profiles of castrated lambs. Twenty Dorper × Santa Inês lambs (20.06 ± 0.76 kg BW) were assigned to a randomized block design, stratified by BW, with the following treatments: CON - 0 g/kg of SM and SM20 - 200 g/kg of SM on DM basis, allocated in individual pens. The diet consisted of 840 g/kg concentrate and 160 g/kg corn silage for 76 days, with the first 12 days as an adaptation period and the remaining 64 days on the finishing diet. The SM20 diet increased blood urea concentration (P = 0.03) while reduced glucose concentration (P = 0.04). Lambs fed SM showed higher subcutaneous fat deposition (P = 0.04) and higher subcutaneous adipocyte diameter (P < 0.01), in addition to reduced meat lipid oxidation (P < 0.01). Soybean molasses reduced the quantity of branched-chain fatty acids in longissimus thoracis (P = 0.05) and increased the quantity of saturated fatty acids (P = 0.01). In the transcriptomic analysis, 294 genes were identified as differentially expressed, which belong to pathways such as oxidative phosphorylation, citric acid cycle, and monosaccharide metabolic process. In conclusion, diet with SM increased carcass fat deposition, reduced lipid oxidation, and changed the energy metabolism, supporting its use in ruminant nutrition.

Fatty acid profile and carcass traits of feedlot Nellore cattle fed crude glycerin and virginiamycin.

Forty-eight bulls with an initial body weight (BW) of 408.4 ±â€¯22.2 kg (age = 21 ±â€¯2 months) were used in a randomized complete block design arranged in a 2 × 2 factorial design. The treatments were diets without virginiamycin (VM-) or with virginiamycin, at 25 mg/kg of dry matter (DM, VM+), and diets without crude glycerin (CG-) or with crude glycerin, at 100 g/kg DM (CG+). The cold carcass weight and cold carcass dressing (P ≤ 0.05) was greater in bulls fed crude glycerin diets. Total unsaturated fatty acids (UFA) were 6.08% higher, and cooking weight loss was 10% lower in bulls fed CG+ diets, compared to bulls fed CG- diets (P = 0.0081). Crude glycerin at 100 g/kg DM could be a suitable replacement for VM, as it led to a slight increase in UFA deposition in meat. However, simultaneous administration of VM and CG did not positively affect performance and carcass traits of feedlot Nellore cattle.