Evaluation of yeast-based additives, as an alternative to ionophores, on rumen fermentation of ruminant diets using an in vitro gas production system

IntroductionThe study aimed to assess yeast-based additives' effects, as monensin alternatives, on rumen fermentation parameters, greenhouse gas emissions, and ruminal kinetics of ruminant diets using an in vitro system. Three experiments were conducted, each individually evaluating escalating levels of three yeast-based additives.MethodsThree experiments were designed: Experiment 1 evaluated prebiotic blend 1—yeast culture [Saccharomyces cerevisiae (Scer)], beta-glucans, fructooligosaccharides, galactooligosaccharides, and mannanoligosaccharides; Experiment 2 investigated prebiotic blend 2—beta-glucan fractions and mannanoligosaccharides from Scer; Experiment 3 examined yeast cells—hydrolyzed, inactivated, and spray-dried yeast (Scer) cells. Uniform experimental design and procedures were employed across the three experiments. Each experiment had six treatments: monensin (Rumensin®, 25 mg/kg DM) as positive control, and yeast additive levels (0, 533, 1,067, 1,600, and 2,133 mg/kg on DM basis) added to ruminant diets (60% corn silage and 40% concentrate). An in vitro gas production (GP) system with 50 AnkomRF bottles assessed total GP (at 24 and 48 hours), kinetics, fermentation profiles, methane (CH4), and carbon dioxide (CO2) concentrations. Comparison with monensin utilized Dunnett’s test (5%). Yeast additive levels were analyzed for linear and quadratic responses.ResultsIn Experiment 1, the 1,600 mg/kg yeast additive had lower concentrations of propionate, isobutyrate, valerate, and branched-chain volatile fatty acids (BCVFAs), and a higher acetate concentration and acetate-to-propionate ratio than monensin. In Experiment 2, the 1,600 mg/kg yeast additive led to lower total VFA and isovalerate concentrations than monensin. Additionally, compared to the 1,067 mg/kg yeast additive, monensin showed lower isovalerate concentration and higher NH3-N concentration. In Experiment 3, the 533 mg/kg yeast additive resulted in lower valerate and BCVFA concentrations, and higher CH4 and CO2 concentrations than monensin. Monensin had lower total VFA, butyrate, and acetate-to-propionate ratio, and higher propionate concentration compared to the 2,133 mg/kg yeast additive.DiscussionCollectively, these findings suggest yeast-based additives could be monensin alternatives, enhancing animal nutrient utilization efficiency and contributing to improved livestock sustainability

Soybean meal replaced by slow release urea in finishing diets for beef cattle

Objetivou-se avaliar os efeitos da substituição do farelo de soja por uréia de liberação lenta (0, 33, 66 e 100%) em dietas com dois níveis de concentrado (40 e 80%) sobre o consumo, digestibilidade parcial e total, fluxo de nutrientes, parâmetros ruminais, produção de proteína microbiana, eficiência proteica e balanço de nitrogênio em novilhos de corte em terminação. Foram utilizados oito novilhos de corte cruzados (Bos taurus x Bos indicus), com peso corporal médio (PC) de 418 ± 40 kg e fistulados no rúmen e abomaso, que foram divididos em dois grupos de quatro, em que cada grupo recebeu um nível de concentrado. A alimentação basal foi composta de silagem de milho e o concentrado foi formulado à base de milho moído fino, farelo de soja, uréia de liberação lenta e mistura mineral. O experimento foi avaliado segundo delineamento em quadrado latino, com agrupamento de dois quadrados simultâneos. Dentro de cada quadrado, foram implementados quatro tratamentos, relativos à substituição da proteína do farelo de soja por uréia de liberação lenta (256 % de PB): 0, 33, 66 e 100 %. Verificou-se efeito linear decrescente (P0,10) entre os tratamentos avaliados. As dietas com 80% de concentrado promoveram maior taxa de passagem (kp) da matéria seca e da matéria orgânica, não havendo diferenças estatísticas (P>0,10) para as kps da PB e da FDNcp. As variáveis relacionadas à taxa de digestão não foram influenciadas (P>0,10) por nenhum dos tratamentos avaliados. Verificou-se efeito cúbico (P0,10) pelos tratamentos avaliados. A ULL diminui o consumo de MS, MO e PB de bovinos em terminação, mantendo, entretanto, o consumo de nutrientes digestíveis totais inalterado. O uso de ULL em substituição ao farelo de soja em dietas para bovinos em terminação não altera a eficiência e a produção de proteína microbiana, a digestibilidade e nem as taxas de digestão e passagem da MS, MO, PB e FDNcp. A substituição do arelo de soja por uréia de liberação lenta permite melhor recuperação do pH ruminal após atingir o valores mínimos em dietas com alto concentrado quando comparada ao farelo de soja.This study evaluated the effects of replacing soybean meal (SBM) by slow-release urea (SRU) in beef cattle diets containing two concentrate levels on intake, partial and total digestibility, nutrients flow, ruminal parameters, microbial protein production, protein efficiency and nitrogen balance in finishing beef steers. Eight crossbred steers were used (average BW of 418 kg) fitted with ruminal and abomasal cannulae. The animals were distributed in two groups of four steers, each group received one of the two levels of the concentrate (40 or 80% of the total DM). The experiment was designed as a Latin square in 2 x 4 factorial scheme, with two energy levels in the diet, and within each square, four levels of replacement of soybean meal protein by slow-release urea: 0, 33, 66 and 100 %. The interaction of concentrate level x SRU levels was not significant (P>0.05) for any variables measure. Thus, the effects of concentrate level and SRU inclusion will be discussed independently. Dry matter (DM) intake, as well as organic matter (OM) intake and crude protein (CP) intake decreased linearly (P 0.10) among treatments. DM and OM passage rates (kp) were greater (P0.05) on DM, OM, CP and NDF passage rate. Digestion rates (kd) were also not affected by any of the treatments (P>0.05). The average kd for DM, OM, CP and NDF were 3.82, 4.21, 1.13 and 2.20%. A cubic effect (P 0.10) for total N in urine in mg/kgBW (average of 148.56 mg/kgBW) and in the concentrations of urea N in the serum (average value of 11.53 mg/dL). Nitrogen intake, N excreted in the feces, nitrogen balance and efficiency of nitrogen use decreased linearly (P <0.10) as the levels of SRU increased in the diet, whereas the amount of nitrogen compounds excreted in urine increased linearly (P <0.10) as SRU replaced SBM in the diet. The production of microbial nitrogen and microbial efficiency were not significantly affected by the experimental treatment (P> 0.10) obtaining average values of 152.02 g/day and 120.18 g/kg TDN, respectively.Coordenação de Aperfeiçoamento de Pessoal de Nível Superio

Glicerina como fonte alternativa de energia em dietas de terminaefio para bovinos de corte

The present work was developed based on three studies. The objective of the firs study was to evaluate the effects of partially replacing dry ground corn with glycerin on ruminal fermentation using a dual-flow continuous culture system. Six fermenters (1,223 i 21 ml) were used in a replicated 3x3 Latin square arrangement with three periods of 10 d each, with 7 d for diet adaptation and 3 d for sample collections. All diets contained 75% concentrate and three dietary glycerin levels (0, 15, and 30% on dry matter basis), totaling six replicates per treatment. Glycerin levels did not affect apparent digestibility of DM (PLin. = 0.13; PQuad, 0.40), OM (Pm, = 0.72; PQuad, = 0.15), NDF (PLin. = 0.38; PQuad. = 0.50) and ADF (PLin- 0.91; PQuad. = 0.18). Also, glycerin inclusion did not affect true digestibility of DM (PLin. 0.35; PQuad_ = 0.48), and OM (Pm. = 0.08; PQuad_ = 0.19). Concentrations of propionate (P 0.01) and total volatile fatty acids (P 0.05) intakes of crude protein, non-fiber carbohydrates, and total digestible nutrients. Digestibility of dry matter, organic matter, neutral detergent fiber, and total digestible nutrients increased quadratically (P 0.05). These results suggest that crude glycerin may be included in finishing beef diets at levels up to 15% without impairing performance and carcass characteristics. For the third study, five in vitro experiments were conducted to evaluate the metabolizable energy and changes on ruminal fermentation, total gas production and greenhouse gases concentration of glycerin compared to corn and starch, as well as when glycerin was added in finishing beef diets. For Exp. 1, a 24 bottles system (AnkomRF Gas Production System, Ankom technology, NY, USA) was used in 4 consecutive runs of 48 h. The treatments were three different feedstuffs: corn, glycerin, and starch. The 24 h total gas production, acetate concentration, and acetate: propionate ratio decreased (P 0.05) 24 h and 48 h total gas production, final pH, NHg-N, total VFA, propionate, and butyrate concentrations. The inclusion of glycerin linearly decreased acetate concentration (P 0.03) and acetate: propionate ratio (P = 0.04). For Exp. 3, a total of 20-serum bottles (155 mL) were used in 4 consecutive runs of 48h. The treatments were the same of Exp. 1. The CH4 concentration increased (P 0.05) on total VFA, and propionate concentration. Compared with glycerin treatment, acetate concentration (P 0.01) and acetate: propionate ratio (P = 0.01) were higher for corn and starch, whereas butyrate and valerate concentrations were higher (P = 0.01) for glycerin. For Exp. 4, a total of 25-serum bottles (155 mL) were used in 4 consecutive runs of 48h. The treatments were the same of Exp. 2. The glycerin inclusion did not affect (P > 0.05) the concentrations of CH4, Co2, final pH, and total VFA, propionate, butyrate, and acetate: propionate ratio. A linear decrease of acetate concentration (P = 0.04) was observed due to inclusion of glycerin in the diets. For Exp. 5, two systems of four 4-L digestion vessels (Daisyll system, Ankom technology, NY, USA) were used in two consecutive runs of 48 h. The treatments were: orchard hay (0.4 g/bag), corn (0.4 g/bag), orchard hay (0.4 g/bag) + glycerin (0.2 g/bag) and corn (0.4 g/bag) + glycerin (0.2 g/bag). Orchard hay with glycerin inclusion presented lowest (P 0.05) between corn with or without glycerin. We concluded that, under these experimental conditions, glycerin contributed more to the enhancement of methanogenesis than carbohydrates, but effectively replaced dietary corn as energy source at up to 30og/kg of the diet.O presente trabalho foi desenvolvido baseado em trés estudos. 0 obj etivo do primeiro estudo foi avaliar os efeitos da substituioao parcial do milho por glicerina sobre a fermentaoao ruminal utilizando urn sistema de cultura continua de fluxo duplo. Seis fermentadores (1,223 i 21 ml) foram utilizados em urn delineamento em quadrado latino 3X3 replicado, corn trés periodos de 10 d cada, 7 d para adaptaoao a dieta e 3 d para coletas de amostras. Todas as dietas continham 75% de concentrado e trés niveis de glicerina na dieta (0, 15, e 30% com base na matéria seca), totalizando seis repetiooes por tratamento. Os niveis de glicerina nao afetaram a digestibilidade aparente da MS (PLm = 0,13; PQuad, = 0,40), MO (PLin. = 0,72; PQuad_ = 0,15), FDN (PLin, = 0,38; PQuad, = 0,50) e FDA (PUD, = 0,91; Pouad. = 0,18). Além disso, a inclusao de glicerina nao afetou a digestibilidade verdadeira da MS (PLin, = 0,35; PQuad_ = 0,48), e MO (Pm, = 0,08; PQuad, = 0,19). As concentraooes de propionato de (P 0,01) e acidos graxos volateis totais (P 0,05) 0 consumo de proteina bruta, carboidratos nao fibrosos e nutrientes digestiveis totais. As digestibilidades da matéria seca, matéria organica, fibra em detergente neutro e nutrientes digestiveis totais aumentaram de forma quadratica (P 0,05). Estes resultados sugerem que o glicerina bruto pode ser incluido em dietas de acabamento de bovinos de corte em niveis de até 15%, sem prejudicar o desempenho e as caracteristicas de carcaca. Para 0 terceiro estudo, cinco experimentos in vitro foram conduzidos para avaliar a energia metabolizavel e as mudancas na fermentacao ruminal, producao total de gases e concentracao de gases do efeito estufa da glicerina, comparada ao milho e ao amido, bem como sua inclusao em dietas de terminacao para gado de corte. Para 0 Exp. 1, um sistema de 24 garrafas (AnkomRF Gas Production System, Ankom technology, NY, USA) foi usado em 4 corridas consecutivas de 48 h. Os tratamentos foram trés diferentes alimentos: milho, glicerina e amido. A producao total de gases as 24 h, a concentracao de acetato e a relacao acetato: propionato diminuiu (P 0,05) as producoes de gases as 24 e 48 h, 0 pH final, N-NH3, AGV total, e as concentracoes de propionato e butirato. A inclusao de glicerina diminuiu linearmente a concentracao de acetato (P = 0,03) e a relacao acetato: propionato (P = 0,04). Para 0 Exp. 4, um total de 25 garrafas (155ml) foram usadas em 4 corridas consecutivas de 48 h. Os tratamentos foram os mesmos do Exp. 3. A inclusao de glicerina nao afetou (P > 0,05) as concentracoes de CH4, Co2, AGV totais, propionato, butirato, relacao acetato: propionato e pH final. Foi observada diminuicao linear (P = 0,04) na concentracao de acetato deVido a inclusao de glicerina nas dietas. Para 0 Exp. 5, dois sistemas de quatro vasos de digestao de 4 L (Daisyll system, Ankom technology, NY, USA) foram usados em duas corridas consecutivas de 48 h. Os tratamentos foram: feno de orchard (0,4 g/saco), milho (0,4 g/saco), feno de orchard (0,4 g/saco) + glicerina (0,2 g/saco) e milho (0,4 g/saco) + glicerina (0,2 g/saco). O feno de orchard com glicerina apresentou a menor (P 0,01) digestibilidade in Vitro da MS, seguido pelo feno de orchard sem adicao de glicerina e pelos tratamentos com milho. A digestibilidade in Vitro da MS nao diferiu (P > 0,05) entre os tratamentos com milho sem on com adicao de glicerina. Como conclusao, sob essas condicoes experimentais, a glicerina contribuiu mais para o aumento da metanogenese do que carboidratos, mas efetivamente substituiu parcialmente o milho como fonte de energia em dietas para bovinos de corte.Conselho Nacional de Desenvolvimento Científico e Tecnológic

Does partial replacement of corn with glycerin in beef cattle diets affect in vitro ruminal fermentation, gas production kinetic, and enteric greenhouse gas emissions?

Five in vitro experiments were conducted with the following objectives: 1) To evaluate the ruminal fermentation of three different single ingredients: corn, glycerin, and starch (Exp. 1 and 2); 2) To assess effects of partially replacing corn with glycerin in beef cattle diets on ruminal fermentation pattern (Exp. 3 and 4); and 3) To evaluate the effects of glycerin inclusion on the extension of ruminal DM digestibility of feeds with high (orchard hay) and low (corn) fiber content (Exp. 5). For Exp. 1 and 2, two in vitro systems (24-bottle AnkomRF and 20-serum bottles) were used in four consecutive fermentation batches to evaluate gas production (GP), fermentation profiles, enteric methane (CH4), and carbon dioxide (CO2) of corn, glycerin, and starch. The 24 h total GP, acetate concentration, and acetate: propionate ratio decreased only when glycerin was added to the diet (P 0.05). The inclusion of glycerin linearly decreased acetate concentration (P = 0.03) and acetate: propionate ratio (P = 0.04). For Exp. 5, two DaisyII incubators were used to evaluate the in vitro dry matter digestibility (IVDMD) of the following treatments: orchard hay; corn; orchard hay + glycerin; and corn + glycerin. Glycerin inclusion decreased orchard hay IVDMD (P 0.05). We concluded that, under these experimental conditions, glycerin has similar energy efficiency when used in replacement of corn and included at up to 300 g/kg in beef cattle diets

Exigências nutricionais de bezerros nelores lactentes

Este trabalho foi conduzido com o objetivo de avaliar as exigências de proteína, energia e macrominerais de bezerros nelores do nascimento aos 180 dias. Foram utilizados 20 bezerros (10 machos e 10 fêmeas) com peso corporal médio de 30±3 kg. Imediatamente após o nascimento, quatro bezerros, dois machos e duas fêmeas, foram abatidos para estimar a composição corporal inicial dos animais restantes no experimento. Aos 90 dias, foram abatidos oito bezerros (quatro machos e quatro fêmeas), o restante dos animais abatidos aos 180 dias. Além do leite, os bezerros foram alimentados com silagem de milho à vontade e concentrado comercial fixado em no máximo 0,5 kg/animal/dia. Foram conduzidos dois ensaios de digestibilidade, aos 30 e 90 dias para estimar os consumos de energia dos bezerros. Após o abate, todos os bezerros tiveram suas meias-carcaças direitas dissecadas. Os conteúdos corporais de proteína, energia e minerais foram estimados pela equação Y = a . PCVZb, sendo PCVZ o peso de corpo vazio. A relação PCVZ/PC dos bezerros foi de 0,9622 e a de ganho (G) de PCVZ/GPC foi de 0,958. As exigências líquidas de proteína e energia aumentaram com o aumento do peso corporal, enquanto as de cálcio diminuíram. As exigências de proteína metabolizável para ganho de 1 kg de PC foram de 216,96 e 261,98 g para bezerros de 100 e 200 kg, respectivamente. Recomenda-se utilizar as seguintes equações para estimar os conteúdos corporais de bezerros Nelore lactentes: proteína (g/dia) = 0,135 × PCVZ1,0351; energia (Mcal/dia) = 1,1798 × PCVZ1,1805; cálcio (g/dia) = 0,091 × PCVZ0,6019; fósforo (g/dia) = 0,00894 × PCVZ0,9629; sódio (g/dia) = 0,00126 × PCVZ0,9791; magnésio (g/dia) = 0,000405 × PCVZ0,9827; potássio (g/dia) = 0,00165 × PCVZ0,9364

Partial Replacement of Ground Corn with Glycerol in Beef Cattle Diets: Intake, Digestibility, Performance, and Carcass Characteristics

<div><p>The objective of this study was to evaluate the effects of replacing dry ground corn with crude glycerol on intake, apparent digestibility, performance, and carcass characteristics of finishing beef bulls. A completely randomized block design experiment with 25 d for adaptation and 100 d for data collection was conducted, in which 3,640 Nellore bulls (367 ± 36.8 kg; 18 ± 3 mo) were blocked by body weight and assigned to 20 pens. Bulls were randomly assigned to one of four treatments: 0, 5, 10, and 15% (dry matter basis) of crude glycerol in the diet. Initially, 20 bulls were slaughtered to serve as a reference to estimate initial empty body weight, which allowed for carcass gain calculation. Bulls were weighed at the beginning, at two-thirds, and at the end of the experiment for performance calculations. Carcass measurements were obtained by ultrasound. Fecal output was estimated using indigestible neutral detergent fiber as an internal marker. Data were analyzed using the mixed procedures in SAS 9.2 (SAS Institute Inc., Cary, NC). Intake of dry matter, organic matter, and neutral detergent fiber decreased linearly (<i>P</i> < 0.05) with crude glycerol inclusion. However, crude glycerol levels did not affect (<i>P</i> > 0.05) intakes of crude protein, non-fiber carbohydrates, and total digestible nutrients. Digestibility of dry matter, organic matter, neutral detergent fiber, and total digestible nutrients increased quadratically (<i>P</i> < 0.05) with the inclusion of crude glycerol in the diet. Crude glycerol inclusion did not change the intake of digestible dry matter, average daily gain, final body weight, carcass gain, carcass dressing, gain-to-feed ratio, <i>Longissimus thoracis</i> muscle area, and back and rump fat thicknesses (<i>P</i> > 0.05). These results suggest that crude glycerol may be included in finishing beef diets at levels up to 15% without impairing performance and carcass characteristics.</p></div

Exigências nutricionais de vacas nelores primíparas lactantes

Objetivou-se avaliar as exigências nutricionais de proteína e energia de vacas nelores em lactação no período de 0 a 180 dias. Foram utilizadas 20 vacas primíparas com peso corporal médio ao parto de 362±25 kg. Quatro vacas foram abatidas logo após o parto e foram consideradas grupo referência. Do parto aos 90 dias, quatro vacas receberam alimentação restrita na proporção de 1,5% do peso corporal (PC), em porcentagem da matéria seca (MS), e 12 foram alimentadas à vontade. Aos 90 dias do pós-parto, foram abatidas oito vacas (quatro de cada oferta alimentar). Dos 90 aos 180 dias, quatro vacas foram realocadas para mantença (1,8% PC em MS) e quatro continuaram em consumo voluntário, sendo todas abatidas ao final do período. Os conteúdos corporais de proteína e energia foram estimados pelo equação Y = a . Xb, em que X é o peso de corpo vazio (PCVZ) e a e b os parâmetros da equação. Foram obtidas relações médias de 0,894 para PCVZ/PC e de 0,936 para ganho de PCVZ (GPCVZ)/ganho de PC (GPC). As exigências líquidas de energia para mantença (ELm) foram de 97,84 kcal/PCVZ0,75 e as de energia metabolizável para mantença (EMm), 140,17 kcal/PCVZ0,75. As eficiências de utilização da energia para mantença e ganho de peso foram 0,70 e 0,44, respectivamente. Os conteúdos corporais de proteína diminuíram com o aumento do PC, enquanto os de energia aumentaram. No leite das vacas, foram determinados teores médios de 3,71; 3,88; e 4,74%, respectivamente, de proteína bruta, gordura e lactose. A exigência de ELm para lactação de vacas nelores é de 97,84 kcal/PCVZ0,75, enquanto a de EMm é de 140,17 kcal/PCVZ0,75 e a de proteína metabolizável, de 52,8 g. Para produzir 1 kg de leite com 4% de gordura, vacas nelores necessitam de 0,300 kg de NDT

Beef cattle carcass classification by two different methods (ultrasound and abattoir).

<p>Fat cover classified as thin (less than 1 mm), scarce (1–3 mm), medium (3–6 mm), uniform (6–10 mm) and excessive (over 10 mm).</p

Ingredient and chemical composition of experimental diets.

<p>Ingredient and chemical composition of experimental diets.</p

Effect of crude glycerol inclusion on average dry matter intake during fecal collection.

<p>Effect of crude glycerol inclusion on average dry matter intake during fecal collection.</p