Nutrient intake, productive and metabolic parameters of Nellore bulls feed a forage free diet using cottonseed cake as a fiber source.

We hypothesized that cottonseed cake in confined Nellore young bulls' diet as fiber source, could maintain or improve the nutrient intake, and productive and metabolic parameters. It was evaluated the total replacement of whole plant corn silage (WPCS) by cottonseed cake (CSC) as a source of fiber in the diet. A completely randomized design with two treatments and 12 replications was used. The treatments were two experimental diets containing 300 g/kg of WPCS or CSC as roughage. All animals at 0, 15, 30, 60 and 112 days were weighed to monitor productive performance and nutrient intake. Dry matter intakes, organic matter, neutral detergent fiber, physically effective neutral detergent fiber, crude protein and non-fiber carbohydrates of the WPCS treatment cattle were higher (p < 0.05), and the ethereal extract intake of cattle fed CSC diet was higher. The BW of cattle fed WPCS was higher in the two initial periods of confinement (p < 0.05). Animals from both treatments showed linear growth during the confinement period. There was a fiber source × period interaction for total weight gain (TWG), average daily gain (ADG) and feed efficiency (FE) (p < 0.05), with the lowest in the first 15 days and the highest at 30 days, reflecting a compensatory gain in animals fed with CSC. Bulls fed with CSC showed negative TWG and ADG in the first period (p < 0.05), but recovered in the following periods, surpassing that of the SC treatment in the last two periods. There was negative EF of bulls fed with CSC in the first period (P < 0.05), but in the following periods the CSC diet did not differ from the WPCS diet. The animals fed CSC diet showed a higher concentration of cholesterol and glucose in the blood plasma (p < 0.05). The forage-free diet containing cottonseed cake as a source of fiber replacing corn silage promoted better animal performance.

Prediction models of intake and productive performance of non-castrated Nellore cattle finished in the feedlot system under tropical conditions.

The objective of this study was to understand and predict the intake and performance of Nellore cattle finished in the feedlot. Individual data from 144 non-castrated male Nellore steers finished in the feedlot between the years 2016 and 2020 were used. Descriptive statistical analyses and Pearson's correlation were performed. The outliers were tested by evaluating the studentized residuals in relation to the values predicted by the equations. Residues that were outside the range of - 2.5 to 2.5 were removed. The goodness of fit of the developed equations was evaluated by the coefficients of determination (r2) and root mean square error (RMSE). The mean dry matter intake (DMI) was 10.2 kg/day, neutral detergent fiber intake (NDFI) was 3.4 kg/day, corresponding to 33.3% of DMI, crude protein intake (CPI) was 1.6 kg/day, and total digestible nutrient intake (TDNI) was 7.1 kg/day. The CPI to ADG ratio was 1.3 kg CPI/kg ADG and the TDNI to CPI ratio was 4.5 kg TDNI/kg CPI. The averages of productive performance were 1.3 kg/day for average daily gain (ADG), 152.6 kg for total weight gain (TWG), and 497.8 kg for final body weight (FBW) in average days in the confinement of 115.7 days. The intake measures correlated significantly with the performance measures, except for carcass yield and days in the feedlot. TWG had a high positive correlation with ADG (r = 0.84), while FBW had a positive correlation (r = 0.86) with hot carcass weight (HCW). Measures of intake, performance, and days in the feedlot can be used as predictors of DMI, FBW, HCW, TWG, and ADG. The prediction equations had satisfactory precision and accuracy for non-castrated Nellore cattle finished in feedlot systems under tropical conditions.

Effect of physically effective neutral detergent fiber on nutrient intake and digestibility, ruminal and blood parameters, and ingestive behavior of confined beef cattle.

We aimed to evaluate the effect of levels of physically effective neutral detergent fiber from forage (NDFfor) on confined cattle's metabolism and ingestive behavior. Four crossbred steers (514.0 ± 4.54 kg BW) rumen-cannulated were used. The animals were randomly distributed in a 4×4 Latin square design, and the treatments were diets with 9.5%, 5.5%, 2.5%, and 0.0% NDF from whole plant corn silage. The trial was divided into 4 periods of 21 days. The dry matter, organic matter (OM), crude protein, neutral detergent fiber (NDF), physically effective NDF 8mm (peNDF8mm) and NDF1.18mm intakes, and the digestibility of OM and NDF showed a quadratic behavior. The rumen pH values showed a decreasing linear, and the time at pH below 5.8 increased linearly in the diets with lower NDFfor. The production of volatile fatty acids and the proportions of propionate and butyrate showed an increasing quadratic behavior. On the other hand, the proportion of acetate fitted a decreasing quadratic equation. With the lower participation of forage in the diets, the time spent on rumination activity decreased in a quadratic way, and the time spent in idleness increased in a quadratic way. The corn silage can be reduced to 135 g/kg DM in the diet to obtain a minimum of 5.5% of NDF from roughage.

Sequential use of nutritional additives in diets for finishing Nellore steers in confinement.

The objective was to evaluate the effect of using prebiotics (Saccharomyces cerevisiae boulardii) or Monensin in the confinement initial phase and replacing monensin with probiotics (Bacillus toyonensis) in the final phase. Forty-eight Nellore steers were used, with an initial mean body weight of 356.2 ± 17.98 kg, distributed in a completely randomized design. Two animals per pen were confined in 80 m2 pens. The experiment was divided into two stages. The first phase lasted from day 1 to the 30th day, during which the animals were divided into two groups of 24 animals each. The treatments were the nutritional additives added to the diet: monensin or prebiotics (Saccharomyces cerevisiae boulardii). In the second phase, each group was subdivided into 12 animals by treatment, which received monensin or probiotics (Bacillus toyonensis). Dry matter intake (DMI), animal performance, and economic evaluation of the use of additives were evaluated. There was no additive effect on DMI, average daily gain, and total weight gain of the animals in the first experimental stage (0-30th day). Likewise, in the second stage (31st-100th day), there was no treatment effect for the variables of intake and performance. There was no effect of the use of different nutritional additives on carcass characteristics. The use of prebiotics sequentially to probiotics promoted gross and net yield that was superior to that of the animals that consumed monensin. Yeasts and bacteria respectively in the first and second phases of confinement can replace monensin in confinement diets.

Prediction models of carcass characteristics from non­castrated Nellore cattle finished in the feedlot system under tropical conditions.

Our objective was to use measures of intake and productive performance to adjust prediction models for the carcass traits of non-castrated Nellore cattle finished in a feedlot. Individual data from 168 non-castrated male Nellore steers finished in feedlot between the years 2016-2021 were used. Descriptive statistical analyzes and Pearson correlation coefficients were performed. The outliers were tested by evaluating the studentized residuals in relation to the values predicted by the equations. Residues that were outside the range of -2.5 to 2.5 were removed. The goodness of fit of the developed equations was evaluated by the coefficients of determination (R2) and root mean square error (RMSE). Models for carcass yield, subcutaneous fat thickness, ribeye area, and shear force were adjusted. Means of 53.5% carcass yield, 4.8 mm subcutaneous fat thickness, 73 cm2 loin eye area, and 8.1 kg shear force were observed. The observed average intakes were 9.9 kg/day of dry matter, 3.3 kg/day of neutral detergent fiber content, 1.5 kg/day of crude protein, and 7.1 kg/day of total digestible nutrients. The average confinement time was 113 days, the average total weight gain was 152.2 kg and the average daily gain was 1.35 kg/day. Intake measures significantly correlated with shear force and subcutaneous fat thickness and ribeye area. Carcass yield was significantly correlated with total weight gain, feedlot time, and hot carcass weight. Measures of nutrient intake, performance, and confinement time can be used as predictors of carcass yield, ribeye area, fat thickness, and shear force of non-castrated Nellore cattle finished in a feedlot. The prediction equations for ribeye area, carcass yield, subcutaneous fat thickness, and shear force showed sufficient precision and accuracy for non-castrated Nellore cattle finished in confinement systems under tropical conditions. All equations can be used with caution to estimate carcass traits of cattle finished in a feedlot using measures of intake and productive performance.

Effects of extruded urea levels on the productive performance and carcass and meat characteristics of Nellore cattle.

Because the non-protein nitrogen sources can be an option for a ruminant diet to replace true-protein sources, we hypothesized that using extruded urea in increasing levels by reducing soybean meal in the diet can maintain or improve the productive performance of beef cattle in a feedlot. It was aimed to evaluate the effects of extruded urea levels on the productive performance and carcass and meat characteristics of Nellore steers in feedlot. Twenty-four Nellore steers, with an average age of 22 months and an average initial weight of 333.5 kg, were used. A completely randomized design was used with four treatments: 50, 60, 70, and 80 g/100 kg BW of extruded urea. There was no effect of extruded urea levels on nutrient intake. The final weight and average daily gain were adjusted by a quadratic equation, with maximum estimated values of 479.18 kg and 1.02 kg/day with the inclusion of 59.71, 54.14, and 54.16 g/100 kg BW of extruded urea, respectively. There was no effect (P > 0.05) of extruded urea levels on hot carcass weight (233.3 kg), carcass yield (53.2%), ribeye area (72.7 cm2), and subcutaneous fat thickness (5.3 mm). Likewise, there was no effect (P > 0.05) of extruded urea levels on meat chemical composition, shear force (8.9 KgF), cooking losses (28.2%), pH (5.6), and meat color parameters. We recommended the use of 70 g/100 kg BW of extruded urea in the diet for finishing Nellore steers in confinement.

Mathematical models to predict the lamb weight at birth and at weaning reared in the tropical warm-climate pasture.

Our objective was to evaluate the productive parameters of ewes and their lambs in relation to ewe age and to develop models for predicting lamb weight at birth and weaning in a tropical warm-climate pasture. Individual data were collected from 273 ewes and 273 lambs, between 2013 and 2021. During this period all animals were kept on pastures of Brachiaria brizantha cv. Marandu All lambs in the experiments were supplemented in creep-feeding. A descriptive statistical analysis was performed using the PROC SUMMARY procedure in SAS (SAS University Edition, SAS Institute Inc. Cary, CA, USA). Pearson correlation coefficients between variables were estimated using the PROC CORR procedure in SAS (SAS University Edition, SAS Institute Inc. Cary, CA, USA). Model adjustments and variable selection were performed using PROC REG in SAS (SAS University Edition, SAS Institute Inc. Cary, CA, USA). The STEPWISE option and Mallow's C(p) were used to select the variables included in the equations. Outliers were identified by evaluating the studentized residuals based on the predicted values from the equations. Residual analysis was predicted by regression minus observed values and those that fell outside the range of -2.5 to 2.5 were removed. Several statistics were used to assess the predictability of the equations, including the coefficients of determination (r2) and mean standard error (RMSE). The average ewe age at lambing was 3.4 ± 1.7 years, with an average weight of 56.9 ± 8,9 kg and average body condition score (BCS) of 2,4 ± 0.8 points. The average ewe age at weaning was 51.1 ± 7.9, with average BCS of 1.8 ± 0.8 points. The average lamb at birthing was 3.9 ± 0.9 kg. The average lamb at weaning was 21.0 ± 4.9, with daily gain of 0.2 ± 0.1 kg/day and total gain of 17.1 ± 4.7 kg birth to weaning. The lamb produced by ewe at lambing was 5.3 ± 1.7 kg/ewe. The lamb weaned by ewe at weaning was 28.7 ± 10.8 kg/ewe. The ratios of lamb produced per ewe at birth and at weaning were 0.1 ± 0.03 and 0.6 ± 0.2, respectively. The lamb's birth weight showed a positive linear relationship with the age of the ewe, increasing by 115 g per year of age. The regression equations adjusted for ewe age had maximum points ranging from 4.2 to 5.2, occurring at average age of 4,7 years. The other characteristics showed a quadratic tendency. The results suggest the culling of ewes at five years of age to generate lambs with ideal weight at birth and at weaning raised in warm tropical pastures.

Characterization and in vitro evaluations of Baru pulp from almond production waste ensiled with different additives.

The silage process is an efficient way of storing nutrients for animal nutrition. Our hypothesis was that the Baru pulp can be preserved in the form of silage, regardless of the use of additives to aid the process. Silages of Baru pulp containing different additives were evaluated through in vitro analysis, fermentation parameters, and composition and thermal analysis including differential scanning calorimetry and thermogravimetry. The treatments consisted of (1) silage with Baru pulp (BP) in natura without additive; (2) BP in natura with acetic acid; (3) BP in natura with formic acids; and (4) BP in natura added with microbial inoculums in a randomized experimental design with three replications per treatment and analyzed in duplicate. The ensiled material was kept in anaerobic conditions for a period of 30 days. BP before and after the silage process presented averages of 67.31 and 66.24% for in vitro digestibility of DM (IVDMD). Microbial inoculant additive was the most effective in reducing pH, followed by acetic acid and formic acid. There were effects of additives on silages for all degradation parameters in ruminal liquid in vitro. It was observed that BP before ensiling had the highest A fraction (7.9 mL gas/100 mg DM), without differing from the silage treated with formic acid (7.1 mL gas/100 mg DM). Similar effects were observed on mass loss (TG) and heat flux (DSC) between the silages. Our findings suggest that Baru pulp with formic acid is more efficient in the conservation and preservation of fermentable carbohydrates as well as in silage production.

Ruminal kinetics and nutritive value of Zuri grass silage harvested at different ages and added with powder molasses.

This study aimed to evaluate the effect of regrowth ages and the use of powdered molasses on nutritional characteristics of Zuri grass (Megathyrsus maximus) silages. A completely randomized design was used, in a 3 × 3 factorial scheme: three regrowth ages (65, 80, and 95 days) and three inclusion levels of powdered molasses of sugarcane (0, 20, and 40 g), with four replications. The chemical composition, fermentation parameters, in vitro digestibility, and in vitro degradation kinetics of the silages were evaluated. Greater dry matter (DM) contents were observed in silages with 95 days with 40 g of molasses. The 65 days of regrowth silages with 40 g of molasses had greater in vitro digestibility of dry matter compared to other treatments. However, lower pH values, N-NH3, DM losses, gas losses, and density were observed in silages with 95 days of regrowth with 40 g of molasses. It is recommended to cut the Zuri grass in the range of 80 to 95 days of regrowth with the addition of 40 g/kg of molasses in powders for the production of silages.

Cotton cake as an economically viable alternative fibre source of forage in a high-concentrate diet for finishing beef cattle in feedlots.

Cotton cake can be a sustainable and economically viable alternative to maize silage as an effective fibre source in the finishing diet of feedlot beef cattle. Thus, the objective was to evaluate the economic viability and the productive performance of Nellore steers finished in feedlots using cotton cake as a source of fibre, replacing maize silage in the diet. Twenty-four non-castrated Nellore steers, with an average weight of 377.8 kg and an age of approximately 24 months, kept in individual pens, were used. The diet was 30% roughage, in the form of maize silage, and a diet without forage containing 30% cotton cake as an effective fibre source, based on dry matter. The design used was completely randomised with two treatments and 12 replications. Effects (p < 0.05) of the dietary fibre source were observed for final body weight (BW), total weight gain, hot carcass weight (HCW) and carcass yield (CY). Revenue and net margin were higher for the treatment with cotton cake. The corn silage diet promoted higher total costs per animal (U$ 408.41 vs. U$ 336.06) and daily costs (U$ 3.65 vs. U$ 3.00). Greater differences were observed between fibre sources for the concentrate cost, and the maize silage diet had a cost U$ 98.29 higher than the treatment with cotton cake (U$ 314.04 vs. U$ 215.75). The cotton cake treatment had a higher cost of U$106.98/animal for the net margin. Cotton cake is a viable alternative and can be used as a source of fibre in forage-free diets without affecting production performance, promoting benefits in economic performance for finishing beef steers in feedlots.

Technologies used in ruminant grazing management: an integrative review.

The objective of this study was to identify the main technologies used in the management of ruminant grazing. We developed a review protocol in which the search terms were previously tested and based on the PVO strategy to determine the guiding question (population [P]: domestic ruminants; variables [V] of interest: grazing management technologies; and outcomes [O]: intake, performance, and productivity of animals raised exclusively on pasture). The guiding question was the following: What technologies are used in the grazing management of domestic ruminants on pasture? The databases used were SCOPUS (Elsevier), SciELO Citation Index, Science Direct, and Wiley Online Library, and the search was carried out until October 15, 2021. The search identified 2683 research articles; however, only 43 were considered eligible and included due to their methodological robustness for data extraction. The most commonly used species were Lolium multiflorum and Lolium perenne (20%), Panicum maximum (18%), and Brachiaria brizantha (14%). The most widely used grazing methods were continuous grazing (53.4%) and intermittent grazing (39.5%). Among the technologies, the most widely adopted were pasture height (55.8%) and herbage allowance (11.6%). The most frequent sampling methods were the use of a ruler (37.2%) and measuring stick (13.9%) to measure the height, and clipping with a frame (18.6%) to measure herbage allowance. The animals used in the included studies were cattle (n = 1335), sheep (n = 839), and goats (n = 41). Pasture height and herbage allowance were the most widely used grazing management technologies, with the data concentrated mainly in Brazil, in studies with continuous grazing by cattle.

Productive characteristics, chemical composition, in vitro digestibility, and degradation kinetics of two Brachiaria grasses at different regrowth ages.

The study aimed at the effect of different regrowth ages on chemical, productive, and morphological characteristics, in addition to the kinetics of gas production and in vitro digestibility of grasses of the genus Brachiaria. The treatments consisted of two regrowth ages (21 and 35 days) and two grass species (Brachiaria brizantha and B. ruziziensis), in plat with a dimension of 10 × 10 with four replications, totaling 16 plats in a completely randomized design. The regrowth age did not change the leaf:stem ratio of the grasses. Ruziziensis-grass had higher crude protein (CP) content in leaves than Marandu-grass (14.0% versus 10.9% respectively). Marandu-grass leaf had higher NDF content than Ruziziensis-grass (65.0 and 58.3%, respectively) and ADF content (39.6 and 33.2%, respectively). The accumulation rate is high in Marandu-grass regardless of the age of regrowth; however, the in vitro digestibility of dry matter of Ruziziensis-grass is better both in the leaf and in the stem. The regrowth age did not influence the dry matter (DM) and neutral detergent fiber (NDF) in vitro digestibility (ivD) of the leaves. The ivDNDF of leaves of both types of grass were similar. There was an increase in the ivDDM of stem when the regrowth age was 21 days. The DM degradation rate was higher in Marandu-grass at both regrowth ages, and the total gas production was higher at 21 days. The parameters evaluated in the dual-pool logistic model showed interaction for age and cultivar, except for fractions λ (lag time) and total gas production. Marandu-grass presented a greater volume of gas for the rapidly degradable fraction and a lower degradation rate. There was a significant interaction for the parameters evaluated in the models between ages and grasses. The exponential model showed interaction in all fractions. Grasses had reduced CP content and increased fibrous fraction as a function of age, with no reduction in leaf DM and NDF digestibility. The Ruziziensis-grass has higher digestibility at the regrowth ages evaluated, while Marandu-grass has higher yields. We recommend adjusting the in vitro degradation kinetics by the dual-pool logistic model.

The influence of protected fat in supplements on the performance and carcass characteristics of Nellore beef bulls in tropical pasture.

The finishing stages for uncastrated Nellore beef cattle on tropical pasture often produce high yielding carcasses with minimal fat cover. This study aimed to evaluate the performance and carcass characteristics of uncastrated Nellore beef bulls fed a diet containing rumen-protected fat during the rainy period for 210 days. Eighty Nellore beef bulls with 28 months of age, and an initial live weight of 416 kg ± 16 kg, were allocated into eight paddocks (7.0 ha), totaling 56 ha, at 10 animals/paddock, in a continuous-grazing system. The pasture characteristics, performance production, loin-eye area (cm2), subcutaneous fat thickness (mm), and rump fat thickness were evaluated. There was no effect (P > 0.05) on the average total weight gain (203.00 kg) and average daily gain (0.98 kg/day). On the other hand, the subcutaneous fat thickness and rump fat thickness were 42.8% and 49.5% greater, respectively, when the animals were fed a diet containing rumen-protected fat inclusion (P < 0.05). Supplementation with rumen-protected fat provided a thicker fat layer in the carcass of Nellore beef bulls grazing on tropical pasture during the rainy period.

Ruminal degradation kinetics of diets with different lipid sources and its influence on intake and milk yield of early lactation crossbred Holstein × Gir cows.

The hypothesized that the dietary inclusion of different lipid sources does not alter diet quality, feed intake, and, consequently, milk yield of cows. Thus, this study aimed to evaluate the effects of supplemental lipid sources for early lactation crossbred cows on milk yield, intake, and diet quality through in vitro digestibility and fermentation kinetics, and to demonstrate which variables have the most impact on each diet using principal component analysis (PCA). Five early lactating crossbred ¾ Holstein × » Gir cows (35 ± 8 days in milk), with a mean body weight of 410 ± 7.15 kg of body weight, were randomly allotted to a 5 × 5 Latin square. The treatments consisted of five experimental diets: a control diet with no additional lipid source and four diets with different lipid sources: cottonseed (242.6 g/kg of dry matter (DM)), sunflower seed (243.0 g/kg of DM), whole soybeans (234.0 g/kg of DM), and soybean oil (42.0 g/kg of DM), which were included at a rate to provide 70 g/kg of lipid. Diets with no additional lipid source and containing whole soybeans had higher DM, OM, and CP digestibility than other treatments. The diet containing soybean oil had the highest EE digestibility. Gas production was highest in the diet containing soybean oil. The dietary treatments did not affect DM intake. Milk yield was lower in cows receiving diets containing cottonseed. Whole soybeans can be included in diets for lactating cows to increase the energy intake without impairing the feed intake and milk yield.

Combinations of by-products from biodiesel production included in the supplement for finishing heifers on deferred pastures.

We hypothesized that by-products from biodiesel production like crambe meal (Crambe abyssinica) totally replace soybean meal (Glycine max) and crude glycerin could partially replace corn (Zea mays). Our aim was to evaluate different supplements with combinations of crambe meal and crude glycerin replacing soybean meal or corn on performance and carcass traits of finishing heifers. Sixty Nellore heifers 18 months old were used, and 298.96 ± 21.99 kg of body weight allotted in Brachiaria brizantha pastures. All heifers were distributed in a randomized complete block design, with four treatments being the following supplements: corn + soybean meal (CS), corn + crambe meal (CCr), corn + soybean meal + crude glycerin (CSG), corn + crambe meal + crude glycerin + (CCrG). The animals were distributed in four paddocks of 13 hectares each, in a continuous grazing system. We evaluated pasture characteristics, intake, performance, carcass traits, characteristics, and centesimal composition of Longissimus thoracis muscle. There was an effect (P < 0.05) of inclusion of crambe meal on the performance of the animals for slaughter weight and daily gain. The supplement containing corn + soybean meal (CS) presented better conversion rates and food efficiency. There was an effect of inclusion of crambe meal and crude glycerin on the centesimal composition of Longissimus thoracis muscle. The use of crambe meal and crude glycerin as alternative sources from the agro-industry of biodiesel in concentrate supplement for finishing heifers in pastures can promote positive effects related to productive performance and carcass characteristics.

Prediction of dry matter intake by meat sheep on tropical pastures.

This study was undertaken to determine whether equations for prediction of dry matter intake (DMI) by meat sheep are valid for animals raised solely on tropical pastures and to propose a new equation to predict the DMI of sheep raised on tropical pastures. The DMI prediction from published equations was evaluated by regressing the predicted and observed values, using the F test, for the identity of the parameters (ß0 = 0 and ß1 = 1) of the regression of predicted on observed data. If the null hypothesis is not rejected, the tested equation accurately estimates DMI. The proposed equation was evaluated in the same way as the published equations. The animal performance and pasture structure and chemical composition data used originated from an experiment conducted with 32 Santa Inês sheep raised on tropical pastures. In the analysis of model adequacy, the null hypothesis was rejected (P < 0.001) and the equations generated predictions that differ (ß0 = 0 and ß1 = 1) from the DMI observed under practical feeding conditions for grazing sheep. The proposed equation, DMI (%LW) = 7.16545 (± 0.76522) - 0.21799 (± 0.01812) * LW + 0.00273 (± 0.00034) * LW2-0.00688 (± 0.00299) * GT + 0.000007 (± 0.000002) * GT2 + 0.00271 (± 0.00108) * GHA, where LW is live weight (kg), GT is grazing time (min/day), and GHA is green herbage allowance (kg DM/100 kg LW), should be used to more accurately predict DMI by grazing sheep.

Biofuel by-product can replace partially corn in supplement for Angus × Nellore heifers: productive performance and meat characteristics.

The aim of this is study was to test the hypothesis that corn can be partially replaced by crude glycerin (at a level of 50%) without affecting performance, ingestive behavior, ruminal parameters, meat composition, and fatty acids profile on the meat of heifers. Sixty-four intact plus four rumen cannulated Angus × Nellore heifers (359.0 ± 12.15 kg BW) were used. The cannulated animals received the same diets as the intact ones to determine the ruminal N-NH3 concentration, pH, and chewing activity weekly. All heifers were maintained in Brachiaria brizantha pasture and supplemented with a concentrate containing corn, soybean meal, urea, premixed minerals, and glycerin partially replacing corn. A completely randomized experimental design was used, with two treatments (corn ground or glycerin + corn ground). The inclusion of crude glycerin (high fat) decreased nutrients intake and ruminal N-NH3 concentration in the rumen but increased lipid intake. Inclusion of glycerin had no effect (P > 0.05) on ruminal pH, daily gain, performance, time spent eating, rumination, idling, or water intake. The moisture, ash, and protein contents of meat were not affected (P > 0.05) by crude glycerin intake. Crude glycerin increased saturated fatty acids (C14:0, C16:0, and C18:0) and decreased unsaturated fatty acids (C18:2n6c and C20:1) in meat. Despite the reduction in nutrient intake, we recommend crude glycerin to replace corn in concentrate because glycerin did not impair the performance, meat composition, and ruminal pH. Therefore, crude glycerin is a by-product that can partially replace corn in diets efficiently.

Lipid rich diet from sunflower seeds can alter the proportion of fatty acids on hybrid Beefalo × Nellore cattle.

We evaluated the lipid level effects in the diet on performance, carcass, and meat characteristics of forty-eight steers and heifers, F1 Beefalo (Bostaurus taurus × Bison bison hybrid) × Nellore (Bos taurus indicus), 22 months old, being 24 steers (393.2 ± 15 kg) and 24 heifers (278.4 ± 8 kg). The animals were distributed in a completely randomized design in a 4 × 2 factorial scheme (lipid levels in diet 55-, 65-, 75-, and 85-g/kg dry matter obtained by whole sunflower grain Helianthus annuus and two sexes). Increased amounts of sunflower grain in diet linearly reduce the proportion of saturated fatty acids (FA) in longissimus thoracis. Diets containing up to 85 g/kg of lipid can be used without negative effects on intake, carcass, and meat quality of Beefalo-Nellore steers and heifers and can be an effective strategy to reduce the proportion of saturated FA and increase unsaturated FA on the meat, which can be beneficial for human consumption.

Crambe meal and crude glycerin from biodiesel production in diets for finishing of crossbred cattle in feedlot.

Our hypothesis is that crambe meal can totally substitute soybean meal and crude glycerin can partially replace the corn in the diet without leading to losses of nutrient intake and productive performance. Two assays were performed using heifers and steers. In the first assay, 24 Beefalo-Nellore heifers with 18 months old with 311.5 ± 5.5 kg, and in the second assay, 24 Beefalo-Nellore steers with 18 months old with 317.0 ± 6.4 kg were evaluated. The experiment was carried out in a randomized complete design, in a 2 × 2 factorial scheme, consisting of two energy sources (corn and crude glycerin) and two protein sources (soybean meal and crambe meal). Both assays had 104 experimental days of feedlot. There was no interaction between the variation sources. There was an effect of protein source on nutrient intake for heifers except to neutral detergent fiber intake, which presented effect of energy source. Heifers fed soybean meal showed higher results for total weight gain and daily weight gain. There was observed effect of energy source on rib eye area and subcutaneous fat thickness. Steers fed soybean meal showed higher neutral detergent fiber intake and non-fibrous carbohydrates. Steers fed corn + crude glycerin showed higher results for total weight gain and daily weight gain. The steers fed soybean meal showed higher averages for subcutaneous fat thickness. Crambe meal and crude glycerin can be used as alternative sources of energy and protein to replace 100% of soybean and 50% of corn, respectively, for finishing Beefalo-Nellore cattle in a feedlot.

Effects of supplementation on production and age anticipation at first mating of ewe lambs in tropical pastures.

Studies on the rearing of ewe lambs in the Cerrado are scarce, so the objective was to evaluate the effects of protein-energy supplementation with 1.6 and 2.4% BW on the productive and reproductive performance of ewe lambs raised on pastures of Brachiaria brizantha cv. Marandu. Twenty-four Texel ewe lambs, with a mean age of 5 months, were distributed in two treatments with provision of energy protein supplementation at levels of 1.6 and 2.4% BW, formulated for average daily gains of 150 and 200 g/day for ewe lambs weighing 20 kg, respectively. The experimental delineation adopted was the completely randomized design, with fifteen repetitions per treatment. The performance of the ewe lambs was evaluated by weight at the beginning and end of the breeding season (BS), average daily gain (ADG), and total weight gain (TWG). The count of fecal eggs was performed monthly. The evaluation of the ewe lambs reproductive organs took place at 8 months of age. The fertility of the ewe lambs was detected by transrectal ultrasonography at the end of the BS. The supplementation level of 2.4% BW was higher for ADG and TWG; however, it did not influence the other performance characteristics. There was no effect of supplementation on the reproductive characteristics, parasite load, and nutrients of the pasture. Pasture nutrients were influenced by the month of use. Supplementation levels were not effective to ensure the reproductive success of 8-month-old ewe lambs.