Different proportions of starch and neutral detergent-soluble fiber in diets for feedlot lambs.

This study evaluated the replacement of starch (ST; cracked corn) by neutral detergent-soluble fiber (NDSF; citrus pulp) and its effects on feed intake, performance, digestibility, carcass traits, and nitrogen balance of lambs. In Experiment 1, male lambs (n = 24, 19.1 ± 1.9 kg body weight [BW]) received: Starch (ST) = 250 g starch/kg dry matter (DM); ST/NDSF = 180 g starch/kg DM + 180 g NDSF/kg DM; or NDSF = 250 g NDSF/kg DM. After 84 d, animals were slaughtered and carcasses were evaluated. In Experiment 2, male lambs (n = 15, 23.2 ± 2.3 kg BW) were used to assess digestibility and nitrogen balance. Final BW, average daily gain, gain to feed and feed intake decreased when animals were fed NDSF (P≤0.002), reflecting in lighter carcasses (P<0.0001). The NDSF decreased edible non-carcass components (P=0.0006), total usable products (P<0.0001), commercial cuts and intramuscular fat (P≤0.02). Except for NDSF and ST, the digestibility of nutrients was improved for NDSF diet (P≤0.04). The use of 250 g NDSF/kg DM as citrus pulp in finishing diets for lambs impairs performance, carcass, meat traits and nitrogen balance. However, the moderate replacement of corn by citrus pulp does not change productive variables.

Effect of adding crude glycerine to diets with feed additives on the feed intake, ruminal degradability, volatile fatty acid concentrations and in vitro gas production of feedlot Nellore cattle.

The effects of adding crude glycerine with sodium monensin or essential oils to beef cattle diets on the intake, degradability of DM and nutrients, rumen concentration of volatile fatty acids (VFA) and in vitro gas production were evaluated. Five ruminally cannulated Nellore steers were randomly assigned to a 5 × 5 Latin square design. The treatments were as follows: CONT, without crude glycerine and additives; EO, with essential oils and without crude glycerine; MON, with sodium monensin and without crude glycerine; EOG, with essential oils and crude glycerine; MONG, with sodium monensin and crude glycerine. Treatments with essential oil and sodium monensin increased the NDF and STC intake and the DM degradability. When crude glycerine was combined with either sodium monensin or essential oil, there was a reduction in DM, NDF and STC intake and an increase in DM and CP degradability of the diets. The adding crude glycerine to essential oil diets reduced the CH4 production. Sodium monensin treatments reduced DM and NDF intake and the production of total gas, CH4 , total VFA and acetic acid concentration. In conclusion, the adding crude glycerine (200 g/kg DM) with either sodium monensin (0.03 g/kg DM) or essential oil (0.5 g/kg DM) can be utilized in diets for Nellore cattle without causing detrimental effects on feed intake and improving the DM degradability.

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 ±â€…0.76 kg body weight [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 dry matter basis, allocated in individual pens. The diet consisted of 840 g/kg concentrate and 160 g/kg corn silage for 76 d, with the first 12 d as an adaptation period and the remaining 64 d 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). SM 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.

This study investigated the effects of incorporating soybean molasses (SM) into the diet of castrated lambs on various aspects of their performance and meat quality. Twenty lambs were divided into two groups: one was fed a control diet without SM whereas the other was fed a similar diet but containing 20% of SM. The feeding trial lasted for 76 d. Results showed that the SM inclusion in the diet led to increased blood urea levels and decreased glucose concentrations. SM inclusion also resulted in lambs with higher levels of subcutaneous fat and larger adipocytes, while reducing meat lipid oxidation. Moreover, SM altered fatty acid composition in the meat, decreasing branched-chain fatty acids and increasing saturated fatty acids. In agreement with these findings, transcriptomic analysis revealed a significant change in the expression of genes related to energy metabolism in the muscle of lambs fed SM. In conclusion, incorporating SM in lamb's diet increased fat deposition, improved meat quality, and induced a transcriptomic change in the muscle energy metabolism, supporting its potential use in ruminant nutrition.

Soybean molasses to replace corn for feedlot lambs on growth performance, carcass characteristics, and meat quality.

Soybean molasses (SBM) is a byproduct of the manufacture of soy protein concentrate and has high energy value. This byproduct has a high potential for use in the nutrition of ruminant animals, mainly in the replacement of other energy feeds such as corn grain. The objective of this study was to evaluate the inclusion of SBM to replace corn grain up to 30% dry matter (DM) in the total diet on growth performance, feeding behavior, carcass characteristics, and meat quality of feedlot lambs (½ Santa Inês × ½ Dorper). Forty intact male lambs with an initial average body weight of 20.6 ± 2.5 kg and approximate age of 120 d were used. The animals were distributed in four treatments (0%, 10%, 20%, and 30% SBM), divided into five randomized blocks according to the initial weight and adapted for 16 d, with diets containing increasing concentrations of concentrate and SBM. Feeding behavior was analyzed at the beginning, middle, and final of the finishing period, and when animals reached 42 d on the finishing diet they were slaughtered. Data were evaluated using SAS software (version 9.4), by polynomial orthogonal contrasts, where the growth performance, carcass characteristics, and meat quality values were analyzed as randomized blocks, and the feeding behavior data as randomized blocks with a repeated measure over time. Significant differences were detected for the contrast 0 vs. SBM treatments, which the inclusion of SBM caused an increase (P ≤ 0.05) in ash intake but decreased the ether extract intake. The intake of DM in % body weight was higher for SBM treatments than 0% treatment (P ≤ 0.05). Feeding behavior, ruminating while lying down and drinking water presented a decreasing linear effect (P ≤ 0.05), and for feeding, efficiency increased with the addition of SBM (P ≤ 0.05). Fatty acids C14:0, C17:0, C17:1, C18:2n6c, C20:2, and C20:3n6 showed lower values ​​with the inclusion of SBM (P ≤ 0.05), while fatty acids C22:0 and C22:6n3 increased. The values ​​of n6 polyunsaturated fatty acids and n-6/n-3 ratio were lower (P ≤ 0.05) for SBM treatments. The values ​​of total polyunsaturated fatty acids showed a decreasing linear effect (P ≤ 0.05) with the inclusion of SBM. The use of up to 30% SBM in DM did not impair animal growth performance and feeding behavior did not cause damages to carcass parameters and still made the meat healthier, improving the n-6/n-3 ratio, therefore can be used to feed finishing lambs.

Meta-analysis of the effect of glycerin inclusion in dairy cattle diet on milk fatty acid profile.

The use of glycerin in diets for dairy cows initially emerged as an alternative for the prevention and control of ketosis. However, despite some controversy, there are still several studies associating glycerin with increases in daily milk yield, with possible changes in its constituents. Therefore, the objective of this study was to evaluate, using a meta-analysis approach, the effect of glycerin inclusion in dairy cow diets on milk fatty acid. Twenty-two peer-reviewed publications with 66 treatment means were included in data set. The effect of glycerin inclusion in diet (treatment) were evaluated using random-effect models to examine the weighted mean differences (WMD) between a control diet (without glycerin in the diet) and the treatment diet. Heterogeneity was explored by meta-regression and subgroup analysis performed for: genetic type; days in milk; experimental period; glycerin in diet; glycerin type and concentrate in diet. Inclusion of glycerin in the diet increased the digestibility of dry matter and protein, as well as ruminal propionate. It did not affect dry matter intake (P = 0.351) and milk yield (P = 0.730). The effect of glycerin inclusion on the milk fat yield is dependent on the genetic group, in which Holstein (WMD = -0.04 kg/d; P = 0.010) and Holstein-crossbreed (WMD = -0.10 kg/d; P < 0.0001) cows produced less fat in milk compared to Jersey cows, when glycerin was included in the diets. Glycine inclusions of up to 100 g/kg in the diet of dairy cows did not negatively affect milk production and composition. However, inclusions above 150 g/kg of glycerin in the diet reduced the concentration of fat, and of unsaturated, monounsaturated, polyunsaturated fatty acids and conjugated linoleic acid (CLA C18: 2 cis-9 and trans-11) in milk. The results reported in our meta-analysis does not demonstrate the effectiveness of glycerin in improving the composition of milk and a group of fatty acids of importance for human health such as C18: 2 cis-9, trans-11 CLA.

Effects of dietary inclusion of high concentrations of crude glycerin on meat quality and fatty acid profile of feedlot fed Nellore bulls.

Crude glycerin, the main by-product of biodiesel production, can replace dietary energy sources, such as corn. The objective of this study was to evaluate the inclusion of up to 30% of crude glycerin in dry matter (DM) of the total diets, and its effects on meat quality parameters of feedlot Nellore bulls. Thirty animals (227.7 ± 23.8 kg body weight; 18 months old) were housed in individual pens and fed 5 experimental diets, containing 0, 7.5, 15, 22.5 or 30% crude glycerin (DM basis). After 103 d (21 d adaptation) animals were slaughtered and the Longissimus muscle was collected. The characteristics assessed were chemical composition, fatty acid profile, cholesterol, shear force, pH, color, water-holding capacity, cooking loss and sensory properties. The increasing inclusion of crude glycerin in the diets did not affect the chemical composition of the Longissimus muscle (P > 0.10). A quadratic effect was observed when levels of crude glycerin were increased, on the concentration of pentadecanoic, palmitoleic and eicosenoic fatty acids in meat (P < 0.05), and on the activity of the delta-9 desaturase 16 and delta-9 desaturase 18 enzymes (P < 0.05). The addition of crude glycerin increased the gamma linolenic fatty acid concentration (P < 0.01), and altered the monounsaturated fatty acids in Longissimus muscle of animals (Pquad. < 0.05). Crude glycerin decreased cholesterol content in meat (P < 0.05), and promoted higher flavor score and greasy intensity perception of the meat (P < 0.01). The inclusion of up to 30% crude glycerin in Nellore cattle bulls`diets (DM basis) improves meat cholesterol and sensory attributes, such as flavor, without affecting significantly the physical traits, the main fatty acid concentrations and the chemical composition.