Total Digestible Nutrients Intake Research Articles

Evaluation of coffee pulp as a feed ingredient for ruminants: A meta-analysis

Abstract This meta-analysis aimed to evaluate the potential of coffee pulp as ruminant feed. The database was developed from 22 related articles containing 94 studies, collected from Scopus and Google Scholar. The parameters integrated were ruminant intake, digestibility, ruminant performance, milk production, milk composition, carcass production, and rumen fermentation. The data were analyzed using a mixed model methodology. The level of coffee pulp was considered as a fixed factor and the different studies as random effects. The results revealed that coffee pulp addition had a significant quadratic effect on reducing the intake of dry matter, crude protein, and total digestible nutrients (P < 0.01), and had a linear response to enhance neutral detergent fiber and acid detergent fiber intake (P < 0.05). However, it should be noted that there were no significant differences in performance, nutrient digestibility, milk production and composition, carcass production, and rumen fermentation. by using coffee pulp as ruminant feed. In conclusion, coffee pulp can be used as an alternative feed ingredient for ruminants. However, it should be applied at the right amount to avoid negative effects on animal performance.

Predicting Microbial Protein Synthesis in Cattle: Evaluation of Extant Equations and Steps Needed to Improve Accuracy and Precision of Future Equations.

Predictions of microbial crude protein (MCP) synthesis for beef cattle generally rely on empirical regression equations, with intakes of energy and protein as key variables. Using a database from published literature, we developed new equations based on the intake of organic matter (OM) and intakes or concentrations of crude protein (CP) and neutral detergent fiber (NDF). We compared these new equations to several extant equations based on intakes of total digestible nutrients (TDN) and CP. Regression fit statistics were evaluated using both resampling and sampling from a simulated multivariate normal population. Newly developed equations yielded similar fit statistics to extant equations, but the root mean square error of prediction averaged 155 g (28.7% of the mean MCP of 540.7 g/d) across all equations, indicating considerable variation in predictions. A simple approach of calculating MCP as 10% of the TDN intake yielded MCP estimates and fit statistics that were similar to more complicated equations. Adding a classification code to account for unique dietary characteristics did not have significant effects. Because MCP synthesis is measured indirectly, most often using surgically altered animals, literature estimates are relatively few and highly variable. A random sample of individual studies from our literature database indicated a standard deviation for MCP synthesis that averaged 19.1% of the observed mean, likely contributing to imprecision in the MCP predictions. Research to develop additional MCP estimates across various diets and production situations is needed, with a focus on developing consistent and reliable methodologies for MCP measurements. The use of new meta-omics tools might improve the accuracy and precision of MCP predictions, but further research will be needed to assess the utility of such tools.

A Meta-Analysis to Determine Protein and Energy Requirements for Maintenance and Growth of Cattle in Indonesia

The meta-analysis in this study was conducted to determine the protein and energy requirements of various cattle breeds in Indonesia. A database was compiled from various research articles that involved cattle as the experimental animals, focusing on studies that reported energy and protein intake, initial body weight, and average daily gain (ADG). In total, 57 articles covering different cattle breeds in Indonesia, with 191 data points, were integrated into the database. The database specified different breeds (Aceh, Bali, Madura, Peranakan Ongole (PO), Sumba Ongole (SO), and Local) and sexes. Regressing ADG used to determine maintenance and gain requirements of dry matter, energy, and protein with dry matter intake (DMI), total digestible nutrient intake (TDNI), and crude protein intake (CPI), respectively. An intercept (where ADG= 0 kg/kg MBW/d) and a slope (required nutrient intake per unit ADG) were taken as maintenance and gain requirements, respectively. Results revealed that protein and energy requirement for maintenance (CPm and TDNm) of all cattle breeds varied in values, ranging from 0.0014 to 0.0102 kg/kg MBW/d (Madura and PO breeds) and 0.0232 to 0.0687 kg/kg MBW/d (Aceh and PO breeds), respectively. Each cattle breed in Indonesia has its particular CP and TDN requirements. Both energy and protein requirements for maintenance (CPm and TDNm) and gain (CPg and TDNg) varied in value for each breed.

Performance of grazing cows fed supplements from coproducts of biodiesel industry replacing soybean meal.

The objective of the present study was to evaluate the substitution of soybean meals by biodiesel co-products on the performance and nutrient balance of lactating cows on pasture. Twelve dairy cows (7/8 Holstein-Gir) in early lactation were included in this feeding trial. These animals had an average daily milk yield of 21.1kg and were distributed in a 4 × 4 triple Latin square experimental design. Protein supplements fed to these lactating cows contained peanut meal, cotton and sunflower as a complete replacement for soybean meal. Nutrient intake and digestibility, milk production, microbial protein synthesis, energy and protein balance were the parameters assessed in this study. Supplements containing different biodiesel co-products did not influence (P > 0.05) the level of forage intake, supplementation and nutrient by lactating cows, except for the total digestible nutrients (TDN) intake which was higher (P ≤ 0.05) in cows supplemented with cottonseed meal. The cotton meal also promoted higher digestibility of TDN (P = 0.001) and total carbohydrates (TCHO; P = 0.001) of the diet and, as a result, higher energy consumption (P = 0.01) and lower negative energy balance (P = 0.01). Cottonseed meal is a co-product of the biodiesel industry that has the ability to replace soybean meal as a source of protein in the supplement without affecting performance and promoting greater energy availability, demonstrating its ability to reduce the effects of negative energy balance in cows at the beginning of lactation kept on tropical pastures.

Effects of condensed tannin-enriched alternative energy feedstuff supplementation on performance, nitrogen utilization, and rumen microbial diversity in grazing beef cattle

This study aims to investigate the effects of alternative energy feedstuff supplementation containing condensed tannin (CT) on palisade grass pastures, focusing on intake, nutrient digestibility, animal performance, ruminal and blood parameters, nitrogen use efficiency (NUE), and its impacts on the ruminal bacterial community in backgrounding Nellore young bulls. Two experiments were conducted simultaneously. Animal performance was evaluated in Experiment 1. The experimental design was a completely randomized block; ninety Nellore bulls (Bos taurus indicus) with an average initial body weight (BW) of approximately 240 ± 5 kg were used (64 as testers and 26 as regulators). The feed intake, digestibility of dry matter and nutrients, ruminal parameters, NUE, and the impact on the ruminal bacterial community were evaluated in Experiment 2. The experimental design was a 4 × 4 double Latin square involving eight Nellore bulls with an average initial BW of 290 ± 8 kg, all of which were cannulated in the rumen. The treatments consisted of energy supplementation at 0.3 % of BW with peanut skin (PS), 0.3 % of BW with sorghum grain (SG), 0.3 % of BW with soybean hulls (SHs), and a control treatment with a supply of mineral salt ad libitum. The total digestible nutrient intake was lower in animals that received only mineral supplements (p < 0.005). The dry matter (DM) intake decreased with treatment PS, while the DM and nutrient digestibility increased (p < 0.005). There was a reduction in ruminal ammonia nitrogen and an improvement in NUE in the PS treatment (p < 0.005). However, the bacterial and Archaea populations were unaffected (p = 0.619). Individual animal performance and gain per kg were increased in the treatment with supplements containing or without CT compared to the mineral supplement (p < 0.001). The NUE improved in treatments PS, SG, and SH (p < 0.01). Feedstuff supplementation using no edible foods by products containing CTs is an effective alternative energy source for Nellore bulls grazing on palisade grass during the rainy season. Additionally, it can be used to mitigate the environmental impacts of N excretion.

Effect of feeding Bengal gram residual forage-based pelleted total mixed ration on growth performance, nutrient availability, carcass traits and composition in finisher Barbari kids.

The study aimed to assess the impact of feeding Bengal gram residual forage-based pelleted Total Mixed Ration (TMR) with varying concentrate (C) to roughage (R) ratios on feed intake, nutrient utilization, growth, and carcass characteristics in Barbari kids. Sixteen weaned male Barbari kids (av. age, 233 ± 11 days; weight, 13.86 ± 0.76kg) were divided into two groups (T1 and T2), each receiving different pelleted diets (TMR) with distinct concentrate to roughage ratios (T1 with 60:40; T2 with 40:60). The kids were fed for 133 days, and a digestion trial was conducted at the end of the study. After completion, all kids were slaughtered. Although, kids under T1 consumed higher (P < 0.001) amount of dry matter, and crude protein compared to T2, which was due to a higher concentrate to roughage ratio in T1. But, the average daily body weight gain (ADG) of finisher kids was 88.53, and 79.83g/d/kid in T1 and T2, respectively; however, the difference was non-significant. Digestibility of organic matter, crude protein, and total carbohydrate was also greater in T1 compared to T2. Total digestible nutrients intake was higher (P < 0.001) in T1; similarly intake of digestible energy, and metabolizable energy were significantly increased (P < 0.01) in T1 compared to T2. Concentrations of volatile fatty acids and NH3-nitrogen were also enhanced (P < 0.05) in T1 compared to T2. We observed similar carcass weight, and dressing percentage in both groups, and carcass composition remained unaffected. The pelleted diet containing greater ratio of concentrate: roughage (60:40) had no additional benefits in terms of ADG, and carcass traits in finisher kids. Therefore, it may be concluded that the Bengal gram residual forage-based pelleted TMR diet containing C40: R60 (TDN 57.13%, DCP 7.64%, ME 9.11MJ/kg feed) is suitable for optimizing growth performance with desirable carcass traits, and meat composition in finisher Barbari kids reared under the intensive system.

Full-fat corn germ improves the performance and milk fat yield of Girolando cows fed sugarcane bagasse and cactus cladodes as forage sources.

We investigated the effects of replacing ground corn with full-fat corn germ (FFCG) on milk production, milk composition, and nutrient use in cows fed sugarcane bagasse and cactus cladodes. Ten multiparous Girolando cows (average body weight 500 ± 66kg, 90 ± 15 days in milk) were distributed in a replicated 5 × 5 Latin Square and assigned to five dietary treatments containing 0%, 25%, 50%, 75%, or 100% of full-fat corn germ in substitution to ground corn. Full-fat corn germ increased fat-corrected milk yield by 2.2kg/day and the synthesis of fat, lactose, and total solids in milk by 94.4, 60.0, and 201.10g/day, respectively (p < 0.05). Cows fed corn germ quadratically increased (p < 0.05) dry matter intake by 1.01kg/day, with the intake of crude protein and total digestible nutrients following the same pattern. Conversely, the substitution of corn for full-fat corn germ linearly reduced (p < 0.05) the total non-fiber carbohydrate intake from 5.79 to 4.40kg/d. Except for ether extract and non-fiber carbohydrates, full-fat corn germ did not alter (p > 0.05) nutrient digestibility. Cows fed corn germ excreted less (p < 0.05) urea-N in milk and urine N. These results demonstrate that full-fat corn germ can partially replace ground corn to enhance the milk production efficiency of crossbred cows fed cactus cladodes and sugarcane bagasse. Furthermore, including sugarcane bagasse in FFCG-supplemented diets prevents milk fat depression in cows fed cactus cladodes.

Feeding behavior, intake pattern, and nutrient sufficiency of sheep fed sorghum straw silage and concentrate

This study aimed to determine the behavior, intake pattern, and nutritional sufficiency level of sheep fed sorghum straw silage and concentrate. Twelve male local sheep weighing 13.13 ± 2.39 kg were kept in individual pens with a size of 80 × 125 cm2. The concentrate comprised soybean meal, rice bran, ground corn, mineral premix, and urea. Forage and concentrate were given at the same time in different feed bunks and were available all the time. The data observed were related to behavior, feed intake, and growth. The behavioral activities observed were duration of eating, mineral block licking, drinking, rumination, laying, and other activities. The feed intakes observed were hourly intake and daily intake. Behavioral data and dry matter intake patterns were analyzed descriptively, while nutritional sufficiency was analyzed using a one-sample t test compared to the nutrient requirements of local sheep for an increase in body weight of 100 grams per day. The activities carried out within 24 hours were eating (24.00%), ruminating (19.05%), mineral block licking (3.45%), drinking (0.28%), laying (31.02%), and other activities (31.02%). The feed intake ratios of sorghum straw silage and concentrate were 10.89% and 89.11%, respectively, with an average daily gain of 140.00 g per head per day. The total dry matter intake was 737.34 g, consisting of a total intake of crude protein and total digestible nutrients of 16.48% and 71.44%, respectively, exceeding the needs of local sheep for a daily gain of 100 g per day. Sheep can use sorghum straw silage as a forage source and regulate their consumption to meet their nutritional needs.

Supplementation strategies for ewes during gestation and lactation.

Concentrated supplementation of ewes is a strategy to increase productivity. The objective was to evaluate the effects of supplementation in the diet of ewes before, during and in the final third of pregnancy and lactation on, the performance and production and composition of colostrum and milk. Forty animals were distributed in a completely randomized design, into the following treatments: CONT = control treatment with mineral salt supplementation only, SSREPRO = supplementation started 20 days before the estrus synchronization (ES) protocol, SSPREG = suplementação a partir da confirmação da gestação (60 days after ES), and SEPREG = supplementation in the third end of pregnancy (90 days after ES). Supplementation adoption changed (P < 0.05) the intake of organic matter, crude protein, neutral detergent fiber, the percentage of total digestible nutrients, and digestibility of dry matter, acid detergent fiber, non-fiber carbohydrates, and ether extract with their respective intake, in addition to colostrum and milk production and composition and animal performance. No difference (P > 0.05) was observed for organic matter, crude protein, and neutral detergent fiber digestibility and total digestible nutrient intake. Thus, supplementation in the final third of pregnancy may result in heavier lambs at weaning, reduction in slaughter time.

Can the post-ruminal urea release impact liver metabolism, and nutritional status of beef cows at late gestation?

We aimed to evaluate the effects of post-ruminal supply of urea (PRU) on nutritional status, and liver metabolism of pregnant beef cows during late gestation. Twenty-four Brahman dams, pregnant from a single sire, and weighing 545 kg ± 23 kg were confined into individual pens at 174 ± 23 d of gestation, and randomly assigned into one of two dietary treatments up to 270 d of gestation: Control (CON, n = 12), consisting of a basal diet supplemented with conventional urea, where the cows were fed with diets containing 13.5 g conventional urea per kg dry matter; and PRU (PRU, n = 12), consisting of a basal diet supplemented with a urea coated to extensively prevent ruminal degradation while being intestinally digestible, where the cows were fed with diets containing 14,8 g urea protected from ruminal degradation per kg dry matter. Post-ruminal supply of urea reduced the urine levels of 3-methylhistidine (P = 0.02). There were no differences between treatments for dry matter intake (DMI; P = 0.76), total digestible nutrient (TDN) intake (P = 0.30), and in the body composition variables, such as, subcutaneous fat thickness (SFT; P = 0.72), and rib eye area (REA; P = 0.85). In addition, there were no differences between treatments for serum levels of glucose (P = 0.87), and serum levels of glucogenic (P = 0.28), ketogenic (P = 0.72), glucogenic, and ketogenic (P = 0.45) amino acids, neither for urea in urine (P = 0.51) as well as urea serum (P = 0.30). One the other hand, enriched pathways were differentiated related to carbohydrate digestion, and absorption, glycolysis, pyruvate metabolism, oxidative phosphorylation, pentose phosphate pathway, and biosynthesis of amino acids of the exclusively expressed proteins in PRU cows. Shifting urea supply from the rumen to post-ruminal compartments decreases muscle catabolism in cows during late gestation. Our findings indicate that post-ruminal urea supplementation for beef cows at late gestation may improve the energy metabolism to support maternal demands. In addition, the post-ruminal urea release seems to be able to trigger pathways to counterbalance the oxidative stress associated to the increase liver metabolic rate.

The Determination of Nutrient Intake on Productivity and Potential Methane Emission of Fat-Tailed Sheep Fed Odot Grass as a Source of Crude Fibre

The purposes of this study were to examine the determination of crude protein (CP), Crude Fibre (Cfi) and total digestible nutrients (TDN) on the productivity and potential methane emission of fat-tailed sheep (FTS) fed Odot grass (Pennisetum purpureum cv. Mott) as a source of crude fibre. The materials used were 15 male FTS with an initial body weight (BW) of 19.5 kg ± 0.61 (CV = 0.59). The feed consisted of 28.57% Odot grass, 14.29% coffee peel, 4.28% rice bran, 7.86% pollard, 21.43% cassava, 21.43% corn cobs and 2% molasses. Sheep were reared intensively in pens for 30 days. Feed and water were provided ad libitum. The parameters in this study were dry matter intake (DMI), CP intake, Cfi intake, TDN, FTS productivity, and the determination of nutrient intake on FTS productivity and methane output. The data were analysed using correlation regression analysis. The results showed that the DMI was 956.67 g/day, CP intake was 119.31 g/day, Cfi intake was 256,22 g/day, TDN intake was 634.54 g/day, ADG 102,03 g/day and FCR of 10.1 g feed/g ADG. The potential methane emission of FTS-fed Odot grass as a source of fibre was 59.49 litres/day. DMI, CP and TDN positively correlate with methane emission (r=0.77). Cfi intake consumption is very closely related to methane output (r=1). Based on the results of the study, to increase FTS ADGs of 100 g required DM 4.76% BW, CP requirement was 120.8 g/100 gADG and TDN requirement was 642.4 g/100gADG, Cfi requirement was 259.40g/100gADG with methane emission of 60.26 litres.

Inclusion of licuri cake in high-grain diets for steers: Intake, digestibility, carcass characteristics, and meat quality

A high-grain diet is essential to maximize growth and yield as well as to provide high-quality meat in beef cattle. This study evaluated the effects of including licuri cake in high-grain diets for steers on performance and carcass and meat quality. Forty-four crossbred (1/2 Bos taurus × 1/2 Bos indicus) castrated steers at 24 months of age, with an initial weight of 358.19 ± 41.57 kg, were used. The animals were distributed into four treatments that consisted of diets including licuri cake (0, 85, 170, or 255 g/kg, dry matter basis). Dry matter intake and digestibility decreased with the inclusion of licuri cake in the diet. However, the addition of the ingredient did not influence the intakes of total digestible nutrients (6.7 ± 0.5 kg/day) or crude protein. Licuri cake inclusion did not influence weight gain (1.5 ± 0.2 kg/day) or hot carcass weight (255.1 ± 24.9 kg). There was also no effect on carcass fat thickness, whereas the cholesterol content in the meat decreased with the addition of the cake. We recommend the inclusion of up to 255 g/kg licuri cake in the diet of feedlot steers fed high-concentrate diets.

Effects of palm kernel cake on nutrient utilization and performance of grazing and confined cattle: a meta-analysis.

A meta-analysis was conducted to evaluate the effects of dietary palm kernel cake inclusion (PKCInclusion) on the nutrient intake and digestibility, as well as on the performance of cattle under grazing and confined systems. Additionally, potential maximum safe levels (MSL) for PKCInclusion were explored for cattle under those systems using a broken-line approach. Overall, 22 studies for 85 treatment means and 747 experimental units were included in the dataset used for the meta-analysis in which, quantitative responses to increasing PKCInclusion levels were fitted using a mixed model, considering the study as a random effect. Additionally, all studies tested a treatment without the inclusion of PKC (PKCInclusion = 0g/kg DM) in the concentrate and total mixed ration fed to grazing and confined animals, respectively. In grazing animals, intake, and digestibility of dry matter (DM), as well as intake of total digestible nutrient (TDN) and digestibility of crude protein (CP) decreased linearly (P < 0.01) as PKCInclusion increased. Conversely, the intake and digestibility of neutral detergent fiber (NDF) increased linearly (P < 0.01). Additionally, the intake of CP showed a quadratic decreasing pattern (P < 0.01) with the increase in dietary PKCInclusion. In confined animals, intake of DM, CP, NDF, and TDN revealed quadratic patterns (P < 0.01) as PKCInclusion increased. The digestibility of DM, CP, NDF, as well as TDN concentration showed a linear decreasing pattern (P < 0.05) as PKCInclusion increased. For performance, data revealed that average daily gain (ADG) decreased linearly (P < 0.01) in grazing and confined animals with the increase in PKCInclusion. Feed efficiency (FE) decreased linearly (P < 0.01) in grazing animals, whereas it showed a linear increase (P < 0.05) in confined animals. Exploration of the quadratic relationships of intake of DM, CP, NDF, and TDN with PKCInclusion in confined animals revealed MSL values for PKC ranging from 85.56 ± 14.2 to 126.4 ± 14.7g PKC/kg DM. In grazing animals, exploration of the quadratic relationship of intake of CP with PKCInclusion, revealed an MSL value of 96.23 ± 9.01g PKC/kg DM. In conclusion, data revealed that the use of PKC in both confined and grazing systems reduces the nutrient utilization and performance of cattle in a dose-dependent manner without a maximum safe level that does not reduce animal performance.

Potencial de silagens de genótipos de capim-elefante como volumoso exclusivo sobre a composição tecidual e a qualidade da carne de cordeiros: um estudo preliminar

ABSTRACT This study aimed to evaluate the effects of diets containing elephant grass genotypes silages as exclusive roughage on leg tissue composition, and physicochemical characteristics of meat of lambs. Twenty-four crossbred male lambs with an average initial body weight of 20.29±2.66kg were distributed in a complete randomized design with three treatments and eight replicates. The treatments consisted of three silages of elephant grass genotypes (IRI-381, Elephant B or Mott), without additives or wilting, as the only roughage. The diets did not affect (P&gt;0.05) the dry matter (898.70±60.10 g/day), crude protein (128.93±6.91g/day), total digestible nutrients (690.20±91.82g/day) intakes, body weight at slaughter (24.83±2.79kg), and carcass yields (P&gt;0.05). The tissue composition of the leg did not differ significantly between silages of elephant grass genotypes (P&gt;0.05). No difference (P&gt;0.05) for the physicochemical characteristics of meat from lambs fed diets tested was observed. Therefore, our results indicate that diets containing 50% elephant grass genotypes silages (IRI-381, Elephant B or Mott), harvested at 60 days of growth, have potential for use in lambs feeding.

Dwarf and tall elephant grass silages: intake, nutrient digestibility, nitrogen balance, ruminal fermentation, and ingestive behavior in sheep.

The objective of this study was to evaluate the exclusive supply of dwarf or tall elephant grass silages, harvested at 60days of growth, without wilting or the use of additives, on intake, apparent digestibility, nitrogen balance, rumen parameters, and ingestive behavior of sheep. Eight castrated male crossbred sheep (57.6 ± 5.25kg body weight), fistulated in the rumen, were distributed in two 4 × 4 Latin squares with four treatments and eight animals per treatment and four periods. The treatments consisted of four elephant grass genotype silages (Mott, Taiwan A-146 2.37, IRI-381, or Elephant B). There was no effect of silages (P > 0.05) on dry matter, neutral detergent fiber, and total digestible nutrient intake. The dwarf-sized elephant grass silages provided higher crude protein intake (P = 0.047) and N intake (P = 0.047), while the IRI-381 genotype silage provided higher non-fibrous carbohydrate intake compared to Mott (P = 0.042), without differing from Taiwan A-146 2.37 and Elephant B silages. There were no differences (P > 0.05) among the digestibility coefficients of the evaluated silages. It was observed that silages produced with Mott and IRI-381 genotypes caused a slight decrease in ruminal pH (P = 0.013), and the propionic acid concentration was higher in the rumen fluid of the animals fed with Mott silage (P = 0.021). Therefore, dwarf or tall elephant grass silages, produced with cut genotypes at 60days of growth and without the use of additives or wilting process, can be used in sheep feeding.

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 10.2kg/day, neutral detergent fiber intake (NDFI) was 3.4kg/day, corresponding to 33.3% of DMI, crude protein intake (CPI) was 1.6kg/day, and total digestible nutrient intake (TDNI) was 7.1kg/day. The CPI to ADG ratio was 1.3kg CPI/kg ADG and the TDNI to CPI ratio was 4.5kg TDNI/kg CPI. The averages of productive performance were 1.3kg/day for average daily gain (ADG), 152.6kg for total weight gain (TWG), and 497.8kg for final body weight (FBW) in average days in the confinement of 115.7days. 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.

Effects of low-fat dried distillers grains on nutrient intake and digestibility in high-concentrate diets

This study aimed to evaluate the effect of including levels of low-fat dried distillers grains without soluble (DDG) in high-concentrate diets on intake and digestibility. Four rumen-cannulated Nellore cattle received four dietary treatments in a 4×4 Latin square experimental design. Treatments included diets without DDG (D0) and varying inclusion levels of DDG at 150 g/kg (D150), 300 g/kg (D300), and 450 g/kg (D450). Four periods of total feces and urine collection were performed to estimate nutrient intake and digestibility and estimate nitrogen balance. Collections of omasum digesta were used to estimate ruminal degradability. The ruminal emptying technique was performed to estimate the ruminal rates of ingestion, passage, and digestion (kd). The inclusion of DDG reduced the intake of total digestible nutrients (TDN) (P < 0.01), dry matter (DM) (P = 0.02), organic matter (OM) (P = 0.02), non-fiber carbohydrates (NFC) (P < 0.01) and ether extract (EE) (P = 0.06). The intake of neutral detergent fiber (NDF) increased linearly (P < 0.01), whereas CP had a quadratic pattern (P = 0.02). The total digestibility in kg/d of DM (P < 0.01), OM (P < 0.01), NFC (P < 0.01) and EE (P = 0.02) decreased linearly. The total digestibility in kg/d of the NDF increased linearly (P < 0.01) and the CP had a quadratic pattern (P = 0.01). The kd of DM (P = 0.01), OM (P < 0.01) decreased linearly and NDF increased linearly (P < 0.01). The amount of N retained did not change (P = 0.72), but the intake of metabolizable protein increased (P = 0.03). Therefore, the inclusion of low-fat DDG in finishing diets reduces TDN intake and reduces the digestibility of almost all nutrients.

Intake, digestibility, nitrogen balance and performance in lamb fed spineless cactus silage associated with forages adapted to the semiarid environment Spineless cactus silages in diets for lambs

The study aimed to evaluate the intake, apparent digestibility, nitrogen balance and productive performance in lamb fed spineless cactus silage associated with forages adapted to the semiarid environment. Forty intact crossbred lambs, with an average body weight of 22.65 ± 1.01 kg, were distributed in a completely randomised design with five treatments (diets based on: spineless cactus silage (SCS), spineless cactus + buffelgrass silage (SCBS), spineless cactus + gliricidia silage (SCGS), spineless cactus + pornunça silage (SCPS) and corn silage (CS; witness) and eight animals per treatment. Intake, apparent nutrient digestibility, nitrogen balance, and performance of animals were evaluated. The SCGS diet showed higher intake of dry matter and organic matter (P<0.05). The SCGS and SCPS diets showed the highest crude protein intake (P = 0.005). Lower intake of ether extract was found in animals receiving diets containing SCS and SCBS (P = 0.001). SCBS and SCGS provided a higher intake of neutral detergent fiber (P = 0.015). SCS and SCGS diets displayed a higher intake of non-fiber carbohydrates (P = 0.003). SCGS diets displayed the highest total digestible nutrients intake (P = 0.001). SCPS diet showed lower digestibility of dry matter, organic matter, and crude protein (P<0.05). SCGS diet showed a lower digestibility coefficient for ether extract (P = 0.009). SCPS diet showed lower digestibility coefficients for neutral detergent fiber (P = 0.022). SCS and SCPS diets showed lower digestibility coefficients for non-fiber carbohydrates (P = 0.011). The CS promoted lower results for intake (P = 0.003), absorbed (P = 0.003) and balance (P = 0.012) for nitrogen. SCPS diet promoted higher excretion of nitrogen via faeces (P = 0.001) and less excretion of nitrogen via urine (P = 0.033). SCGS diet provided a higher final weight (P = 0.006). SCS and SCGS diets provided more significant body weight gain (P = 0.001). Combining spineless cactus with a roughage base allowed weight gains over 200 g/day, proving to be efficient in diets for feedlot lamb and gains similar or superior to corn-based diets.

Predicting microbial crude protein synthesis in cattle from intakes of dietary energy and crude protein.

Accurate predictions of microbial crude protein (MCP) synthesis are needed to predict metabolizable protein supply in ruminants. Since 1996, the National Academies of Sciences, Engineering, and Medicine series on beef cattle nutrient requirements has used the intake of total digestible nutrients (TDN) to predict ruminal MCP synthesis. Because various tabular energy values for feeds are highly correlated, our objective was to determine whether intakes of digestible energy (DE), metabolizable energy (ME), and net energy for maintenance (NEm) could be used as predictors of MCP synthesis in beef cattle. A published database of 285 treatment means from experiments that evaluated MCP synthesis was updated with 50 additional treatment mean observations. When intakes of TDN, fat-free TDN, DE, ME, NEm, dry matter, organic matter, crude protein (CP), ether extract, neutral detergent fiber, and starch were used in a stepwise regression analysis to predict MCP, only intakes of DE and CP met the P < 0.10 criterion for entry into the model. Mixed-model regression analyses were used to adjust for random intercept and slope effects of citations to evaluate intake of DE alone or in combination with CP intake as predictors of MCP synthesis, and the intakes of TDN, ME, and NEm as alternatives to DE intake. Similar precisions in predicting MCP synthesis were obtained with all measures of energy intake (CV = root mean square error [RMSE] as a percentage of the overall mean MCP varied from 9% to 9.67%), and adding CP intake to statistical models increased precision (CV ranged from 8.43% to 9.39%). Resampling analyses were used to evaluate observed vs. predicted values for the various energy intake models with or without CP intake, as well as the TDN-based equation used in the current beef cattle nutrient requirements calculations. The coefficient of determination, concordance correlation coefficient, and RMSE of prediction as a percentage of the mean averaged 0.595%, 0.730%, and 28.6% for the four measures of energy intake, with average values of 0.630%, 0.757%, and 27.4%, respectively, for equations that included CP intake. The TDN equation adopted by the 2016 beef cattle nutrient requirements system yielded similar results to newly developed equations but had a slightly greater mean bias. We concluded that any of the measures of energy intake we evaluated can be used to predict MCP synthesis by beef cattle and that adding CP intake improves model precision.

Effect of dietary inclusion of licuri cake on intake, feeding behavior, and performance of feedlot cull cows.

Licuri cake (LC) is an interesting alternative nutritional component for high-grain diets for ruminants due to its high protein (21.6% CP), fat (12.0% EE), and fiber (62.8% NDF) contents. We investigated the effect of increasing levels of LC inclusion on the intake, digestibility, feeding behavior, performance, and carcass traits of cull cows fed high-grain diets. Forty Zebu cows with an initial weight of 318 ± 38.1 kg, at 105 months of age, were confined in collective stalls and fed (ad libitum) a diet containing 0, 50, 100, or 150 g/kg LC on a diet dry matter (DM) basis. Licuri cake inclusion induced quadratic responses (P < 0.05) in the intakes of DM (9.57 kg/day at 97.8 g/kg LC), crude protein (CP; 1.02 kg/day at 91.7 g/kg LC), and total digestible nutrients (6.68 kg/day at 75.2 g/kg LC). The digestibility of DM, CP, and non-fibrous carbohydrates decreased linearly (P < 0.05). Neutral detergent fiber (NDF) intake and rumination efficiencies increased linearly (P < 0.05) with the inclusion of LC in the diet. The inclusion of LC did not influence (P > 0.05) on daily weight gain, hot carcass weight, or back fat thickness in the carcass. Therefore, we recommend the inclusion of up to 150 g/kg LC in high-grain diets for feedlot cull cows.