Effects of molasses supplementation on animal performance and carcass parameters of beef cattle: a meta-analysis.

Molasses must be one of the most used foods in the diet of ruminant animals; however, there is no consensus on the effect of including molasses on carcass parameters. In this context, the objective was to evaluate the effect of including molasses in the diet of feedlot cattle on performance and carcass parameters. Thirteen peer-reviewed publications with 45 treatment means were included in the dataset. The effect of molasses in beef cattle diets was evaluated by examining the weighted mean differences (WMD) between molasses treatment (diet with molasses) and control diet (diet without molasses). Heterogeneity was explored by meta-regression and subgroup analysis using genetic type and experimental period, molasses in diet (g/kg dry matter (DM)), molasses type, concentrate in diet (g/kg DM), and forage type. The inclusion of molasses in the diet increased dry matter digestibility, but reduced NDF digestibility, carcass weight, subcutaneous, and visceral fat. The main sources of variation for the responses with molasses inclusion on intake, digestibility, performance, and carcass parameters were the level of molasses inclusion and the experimental period. In general context, the inclusion of molasses in the diet between 100 to 150 g/kg of DM did not affect performance and carcass parameters. However, the inclusion of molasses above 200 g/kg reduces the average daily gain and carcass weight.

The effect of dietary inclusion of crude glycerin on performance, ruminal fermentation, meat quality and fatty acid profile of beef cattle: Meta-analysis.

This meta-analysis was carried to evaluate the effect of the use of crude glycerin in diets for beef cattle on the ruminal fermentation, animal performance, physical and chemical characteristics, and fatty acid profile of meat through meta-analysis. Data from forty-eight peer-reviewed publications with 170 treatments means was included in the data set. The effect glycerin in diet were evaluated by examining the weighted mean differences (WMD) between glycerin treatment (diets with crude glycerin) and control diet (without crude glycerin). Heterogeneity was explored by meta-regression and subgroup analysis using genetic type, treatment period, crude glycerin in the diet (g/kg DM), feed systems (pasture or total mixed ration), and concentrate in the diet (g/kg DM). The inclusion of crude glycerin had no effect on the average daily gain, but increased feed efficiency by 3.15% while reducing subcutaneous fat thickness by 3.13%. Inclusion of crude glycerin reduced meat cholesterol by 9.13%, and total saturated fatty acids by 1.05%, and increased total unsaturated (2.02%), monounsaturated (3.17%) fatty acids. However, it did not affect the concentrations of conjugated linoleic acid and omega-3. Crude glycerin inclusions up to 200 g/kg DM did not promote a negative effect on animal performance, carcass and physical-chemical characteristics of meat, and supported an increase in total monounsaturated (1.73%), oleic acid (12.29 mg) and palmitoleic acid (1.24 mg), while reducing myristic acid (3.08 mg), stearic acid (12.00 mg) in beef cattle meat.