Influence of combined yeast culture and enzymatically hydrolyzed yeast on in vitro ruminal fermentation in contrasting feed substrates.

BACKGROUND: Feed additives such as live yeast cultures have increasingly been used in ruminant feeds to improve animal performance and feeding efficiency. However, it is not clear how inactive combined yeast cultures affect ruminal gas production, fermentation kinetics and efficiency. Therefore, this study was done to determine the influence of incubating different substrates with a combined yeast culture + enzymatically hydrolyzed yeast (YC + EHY) on in vitro ruminal gas production, fermentation kinetics and metabolizable energy. Six contrasting substrates (Trichantera gigantea and Glircidia sepium leaves, Brachiaria hybrid (cv. Mulato II) leaf + stem and leaf only, Cynodon nlemfuensis and a commercial concentrate dairy feed) were incubated with and without YC + EHY in buffered rumen fluid and gas production measured at 2, 4, 6, 8, 10, 12, 15, 19, 24, 30, 36, 48 and 72 h post incubation. RESULTS: In vitro fermentation parameters (a, b, a + b and c) were unaffected by YC + EHY except for the lag phase in T. gigantea, which that reduced by 31.3% when it was incubated with YC + EHY. Supplementation with YC + EHY also did not affect metabolizable energy, 72 h organic matter digestibility, 24 h gas or CH4 production within substrate. However, cumulative gas and methane production at peak fermentation in the commercial concentrate feed was reduced by 20% when incubated with YC + EHY. CONCLUSION: It was concluded that YC + EHY has the potential to improve microbial colonization of T. gigantean substrates and reduce gas and methane production at peak fermentation in commercial concentrate feeds. © 2021 Society of Chemical Industry.

Effects of yeast culture supplementation on lactation performance and rumen fermentation profile and microbial abundance in mid-lactation Holstein dairy cows.

The continuous trend for a narrowing margin between feed cost and milk prices across dairy farms in the United States highlights the need to improve and maintain feed efficiency. Yeast culture products are alternative supplements that have been evaluated in terms of milk performance and feed efficiency; however, less is known about their potential effects on altering rumen microbial populations and consequently rumen fermentation. Therefore, the objective of this study was to evaluate the effect of yeast culture supplementation on lactation performance, rumen fermentation profile, and abundance of major species of ruminal bacteria in lactating dairy cows. Forty mid-lactation Holstein dairy cows (121 ± 43 days in milk; mean ± standard deviation; 32 multiparous and 8 primiparous) were used in a randomized complete block design with a 7-d adaptation period followed by a 60-d treatment period. Cows were blocked by parity, days in milk, and previous lactation milk yield and assigned to a basal total mixed ration (TMR; 1.6 Mcal/kg of dry matter, 14.6% crude protein, 21.5% starch, and 38.4% neutral detergent fiber) plus 114 g/d of ground corn (CON; n = 20) or basal TMR plus 100 g/d of ground corn and 14 g/d of yeast culture (YC; n = 20; Culture Classic HD, Cellerate Yeast Solutions, Phibro Animal Health Corp.). Treatments were top-dressed over the TMR once a day. Cows were individually fed 1 × /d throughout the trial. Blood and rumen fluid samples were collected in a subset of cows (n = 10/treatment) at 0, 30, and 60 d of the treatment period. Rumen fluid sampled via esophageal tubing was analyzed for ammonia-N, volatile fatty acids (VFA), and ruminal bacteria populations via quantitative PCR amplification of 16S ribosomal DNA genes. Milk yield was not affected by treatment effects. Energy balance was lower in YC cows than CON, which was partially explain by the trend for lower dry matter intake as % body weight in YC cows than CON. Cows fed YC had greater overall ruminal pH and greater total VFA (mM) at 60 d of treatment period. There was a contrasting greater molar proportion of isovalerate and lower acetate proportion in YC-fed cows compared with CON cows. Although the ruminal abundance of specific fiber-digesting bacteria, including Eubacterium ruminantium and Ruminococcus flavefaciens, was increased in YC cows, others such as Fibrobacter succinogenes were decreased. The abundance of amylolytic bacteria such as Ruminobacter amylophilus and Succinimonas amylolytica were decreased in YC cows than CON. Our results indicate that the yeast culture supplementation seems to promote some specific fiber-digesting bacteria while decreasing amylolytic bacteria, which might have partially promoted more neutral rumen pH, greater total VFA, and isovalerate.

Use of Saccharomyces cerevisiae-based products and effects on rumen environment and performance of sheep subjected to dietary changes / Utilização de produtos à base de Saccharomyces cerevisiae e seus efeitos sobre o ambiente ruminal e desempenho de ovinos submetidos a mudanças de dieta

Natural additives in ruminant diet optimizes animal performance by controlling or modifying the rumen fermentation pattern. The aim of this study was to evaluate the effects of using Saccharomyces cerevisiae products during abrupt changes in dietary starch concentration on ruminal pH maintenance, performance and metabolism of confined sheep. Twenty adult ewes, crossbred Texel x Corriedale(44.7±6.97 Kg BW) were divided into three groups: Control (n=6), Cultron X (yeast culture; n=7) and Cultron Pro (hydrolyzed yeast; n=7), administered at a dose of 5 g/sheep/day (10x1010CFU/g DM). The experiment lasted 20 days divided into four periods, alternating between 40 and 60% concentrate. Blood and ruminal fluid were collected at the end of each period, and daily dry matter intake was measured to determine the average daily gain (ADG). Blood tests included blood count and biochemical parameters such as glucose, urea, total plasma proteins (TPP), liver enzymes, acute phase proteins and minerals. There was an upward trend in ADG in group Cultron X compared to control in period 3. Although, ruminal pH did not differ between groups, protozoan motility was higher in animals supplemented with hydrolyzed yeast. The Cultron Pro group showed an increase in TPP in periods 3 and 4, and AST in periods 2 and 3 compared to the control group. There was no difference in other metabolites. Yeast supplementation is a potential tool in times of feeding challenge, in which yeast culture is the most effective for improving performance of confined sheep being in improving performance of confined sheep.(AU)

A utilização de aditivos naturais na dieta de ruminantes é uma prática que otimiza o desempenho, controlando ou modificando o padrão de fermentação ruminal. O objetivo do estudo buscou avaliar os efeitos da utilização de produtos à base de Saccharomyces cerevisiae durante mudanças na concentração de amido da dieta sobre a manutenção do pH ruminal, desempenho e metabolismo de ovinos confinados. Dessa forma, 20 fêmeas ovinas adultas mestiças das raças Texel e Corriedale (44,7±6,97 PV) foram divididas em três grupos: Controle (n=6), Cultron X (cultura de levedura; n=7) e Cultron Pro (levedura hidrolisada; n=7), administrados na dose de 5 g/ovelha/dia (10x1010ufc/g de MS). O experimento teve duração de 20 dias divididos em quatro períodos, alternando entre 40 e 60% de concentrado. Foram realizadas coletas de sangue e líquido ruminal ao final de cada período e mensuração da ingestão de matéria seca diariamente, a fim de determinar o ganho médio diário (GMD). As análises sanguíneas incluíram hemograma e parâmetros bioquímicos como glicose, ureia, proteínas plasmáticas totais (PPT), enzimas hepáticas, proteínas de fase aguda e minerais. Houve tendência de aumento no GMD no grupo Cultron X em relação ao controle no período 3. Apesar do pH ruminal não diferir entre grupos, a motilidade de protozoários foi melhor nos animais suplementados com levedura hidrolisada. O grupo Cultron Pro apresentou aumento de PPT nos períodos 3 e 4 e aumento nos níveis da enzima hepática AST nos períodos 2 e 3 em comparação ao grupo controle. Não houve diferença nos demais metabólitos. A suplementação com levedura apresentou-se como potencial ferramenta em momentos de desafio alimentar, sendo a cultura de levedura mais eficaz na melhora da performance de ovinos confinados.(AU)

Use of Saccharomyces cerevisiae-based products and effects on rumen environment and performance of sheep subjected to dietary changes / Utilização de produtos à base de Saccharomyces cerevisiae e seus efeitos sobre o ambiente ruminal e desempenho de ovinos submetidos a mudanças de dieta

ABSTRACT: Natural additives in ruminant diet optimizes animal performance by controlling or modifying the rumen fermentation pattern. The aim of this study was to evaluate the effects of using Saccharomyces cerevisiae products during abrupt changes in dietary starch concentration on ruminal pH maintenance, performance and metabolism of confined sheep. Twenty adult ewes, crossbred Texel x Corriedale(44.7±6.97 Kg BW) were divided into three groups: Control (n=6), Cultron X (yeast culture; n=7) and Cultron Pro (hydrolyzed yeast; n=7), administered at a dose of 5 g/sheep/day (10x1010CFU/g DM). The experiment lasted 20 days divided into four periods, alternating between 40 and 60% concentrate. Blood and ruminal fluid were collected at the end of each period, and daily dry matter intake was measured to determine the average daily gain (ADG). Blood tests included blood count and biochemical parameters such as glucose, urea, total plasma proteins (TPP), liver enzymes, acute phase proteins and minerals. There was an upward trend in ADG in group Cultron X compared to control in period 3. Although, ruminal pH did not differ between groups, protozoan motility was higher in animals supplemented with hydrolyzed yeast. The Cultron Pro group showed an increase in TPP in periods 3 and 4, and AST in periods 2 and 3 compared to the control group. There was no difference in other metabolites. Yeast supplementation is a potential tool in times of feeding challenge, in which yeast culture is the most effective for improving performance of confined sheep being in improving performance of confined sheep.

RESUMO: A utilização de aditivos naturais na dieta de ruminantes é uma prática que otimiza o desempenho, controlando ou modificando o padrão de fermentação ruminal. O objetivo do estudo buscou avaliar os efeitos da utilização de produtos à base de Saccharomyces cerevisiae durante mudanças na concentração de amido da dieta sobre a manutenção do pH ruminal, desempenho e metabolismo de ovinos confinados. Dessa forma, 20 fêmeas ovinas adultas mestiças das raças Texel e Corriedale (44,7±6,97 PV) foram divididas em três grupos: Controle (n=6), Cultron X (cultura de levedura; n=7) e Cultron Pro (levedura hidrolisada; n=7), administrados na dose de 5 g/ovelha/dia (10x1010ufc/g de MS). O experimento teve duração de 20 dias divididos em quatro períodos, alternando entre 40 e 60% de concentrado. Foram realizadas coletas de sangue e líquido ruminal ao final de cada período e mensuração da ingestão de matéria seca diariamente, a fim de determinar o ganho médio diário (GMD). As análises sanguíneas incluíram hemograma e parâmetros bioquímicos como glicose, ureia, proteínas plasmáticas totais (PPT), enzimas hepáticas, proteínas de fase aguda e minerais. Houve tendência de aumento no GMD no grupo Cultron X em relação ao controle no período 3. Apesar do pH ruminal não diferir entre grupos, a motilidade de protozoários foi melhor nos animais suplementados com levedura hidrolisada. O grupo Cultron Pro apresentou aumento de PPT nos períodos 3 e 4 e aumento nos níveis da enzima hepática AST nos períodos 2 e 3 em comparação ao grupo controle. Não houve diferença nos demais metabólitos. A suplementação com levedura apresentou-se como potencial ferramenta em momentos de desafio alimentar, sendo a cultura de levedura mais eficaz na melhora da performance de ovinos confinados.

Effects of supplements containing different additives on nutritional and productive performance of beef cattle grazing tropical grass.

A grazing trial was carried out to evaluate the inclusion of three feed additives in supplements (crude protein, CP 230 g/kg dry matter, DM) on the performance, voluntary intake, and digestibility of beef heifers grazing Brachiaria decumbens (CP 81 and neutral detergent fiber, NDF 615 g/kg DM). Thirty-five Nellore heifers (21 months of age and 383 ± 6.29 kg of body weight, BW) were used in a completely randomized design. The treatments were as follows: no supplement (control); supplement fed at 1 kg/animal/day without additives (S); supplement with monensin (S + M); supplement with yeast culture (S + YC); and supplement with enzyme complex (S + EC). All of the supplemented heifers had greater (P < 0.1) average daily gain (∼0.186 kg/day) compared to the control treatment (0.014 kg/day). Average daily gain and final BW were similar (P > 0.1) among supplemented heifers. Monensin inclusion in the supplement decreased (P < 0.1) forage DM (expressed as g/kg BW) and NDF intake (expressed as kg/day and as g/kg BW). All of the feed additive inclusions decreased (P < 0.1) NDF digestibility. In conclusion, the heifers' performance was improved by concentrate supplementation. However, the inclusion of additives did not enhance this effect.