Quantification by real-time PCR of cellulolytic bacteria in the rumen of sheep after supplementation of a forage diet with readily fermentable carbohydrates: effect of a yeast additive

Mosoni, Pascale; Chaucheyras‐Durand, Frédérique; Béra-Maillet, Christel; Forano, Evelyne

doi:10.1111/j.1365-2672.2007.03517.x

Cited by 161 publications

(125 citation statements)

References 46 publications

(68 reference statements)

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Indeed, they are at the first level of the microbial trophic chain transforming plant cell wall polysaccharides from feeds into volatile fatty acids, CO 2 and H 2 . They are thus considered as a major microbial functional group in the rumen with a population estimated at E10 9 cells/ml digesta either by culture or by molecular methods (Mosoni et al, 2007). Most members of this group produce H 2 as a main end product of fermentation, which under normal physiological conditions, is in turn rapidly used by methanogens.…”

Section: Plant Fibre Degradation and H 2 Productionmentioning

confidence: 99%

Microbial ecosystem and methanogenesis in ruminants

Morgavi

Forano²,

Martin

et al. 2010

Animal

Self Cite

502

406

View full text Add to dashboard Cite

Ruminant production is under increased public scrutiny in terms of the importance of cattle and other ruminants as major producers of the greenhouse gas methane. Methanogenesis is performed by methanogenic archaea, a specialised group of microbes present in several anaerobic environments including the rumen. In the rumen, methanogens utilise predominantly H 2 and CO 2 as substrates to produce methane, filling an important functional niche in the ecosystem. However, in addition to methanogens, other microbes also have an influence on methane production either because they are involved in hydrogen (H 2 ) metabolism or because they affect the numbers of methanogens or other members of the microbiota. This study explores the relationship between some of these microbes and methanogenesis and highlights some functional groups that could play a role in decreasing methane emissions. Dihydrogen ('H 2 ' from this point on) is the key element that drives methane production in the rumen. Among H 2 producers, protozoa have a prominent position, which is strengthened by their close physical association with methanogens, which favours H 2 transfer from one to the other. A strong positive interaction was found between protozoal numbers and methane emissions, and because this group is possibly not essential for rumen function, protozoa might be a target for methane mitigation. An important function that is associated with production of H 2 is the degradation of fibrous plant material. However, not all members of the rumen fibrolytic community produce H 2 . Increasing the proportion of non-H 2 producing fibrolytic microorganisms might decrease methane production without affecting forage degradability. Alternative pathways that use electron acceptors other than CO 2 to oxidise H 2 also exist in the rumen. Bacteria with this type of metabolism normally occupy a distinct ecological niche and are not dominant members of the microbiota; however, their numbers can increase if the right potential electron acceptor is present in the diet. Nitrate is an alternative electron sinks that can promote the growth of particular bacteria able to compete with methanogens. Because of the toxicity of the intermediate product, nitrite, the use of nitrate has not been fully explored, but in adapted animals, nitrite does not accumulate and nitrate supplementation may be an alternative under some dietary conditions that deserves to be further studied. In conclusion, methanogens in the rumen co-exist with other microbes, which have contrasting activities. A better understanding of these populations and the pathways that compete with methanogenesis may provide novel targets for emissions abatement in ruminant production.

show abstract

Section: Plant Fibre Degradation and H 2 Productionmentioning

confidence: 99%

Microbial ecosystem and methanogenesis in ruminants

Morgavi

Forano²,

Martin

et al. 2010

Animal

Self Cite

502

406

View full text Add to dashboard Cite

show abstract

“…Therefore, considerable attention has been focused on the fermentative changes in ruminants during switches to high-concentrate diets (Araba et al, 2002;Bevans et al, 2005). Also, rumen microbiological changes have been monitored using cultivation-based techniques (van der Linden et al, 1984;Goad et al, 1998) or molecular methods, such as 16S rRNA gene sequencing (Tajima et al, 2000) or real-time PCR (Tajima et al, 2001;Mosoni et al, 2007). However, few studies simultaneously studied both microbial changes and changes in metabolite production in such induction schemes (Mackie et al, 1978;Goad et al, 1998).…”

Section: Introductionmentioning

confidence: 99%

Rumen chemical and bacterial changes during stepwise adaptation to a high-concentrate diet in goats

Sun

Mao

Zhu

2010

Animal

View full text Add to dashboard Cite

The correlation between rumen chemical and bacterial changes was investigated during a four periodical stepwise adaptation to a high-concentrate diet (concentrate level at 0%, 30%, 50% and 70% for diet I to IV, respectively) in goats. The results showed that ruminal pH decreased from 6.7 to 5.5 after switching from diet I to II, and was maintained at about 5.5 on diet III. Denaturing gradient gel electrophoresis results showed that the rumen bacterial community was relatively stable during the initial three feeding periods, except for the appearance of three bands when diet changed from I to II, suggesting that an appropriate concentrate level can promote the proliferation of some bacteria. After 12 days of feeding diet III, total volatile fatty acid (VFA) concentration and butyrate proportion decreased. At days 2 and 3 of feeding diet IV, ruminal pH declined sharply to 5.3 and 4.7, respectively, and total VFA concentration decreased further while lactic acid concentration increased markedly, suggesting a relation between lactic acid accumulation and ruminal pH decline. At the same time, many bacteria disappeared, including most fibrolytic-related bacteria while Streptococcus bovis and Prevotella-like species dominated. Interestingly, Succinivibrio dextrinosolvens-like species maintained throughout the experiment, suggesting its tolerance to low pH. In conclusion, rumen bacterial community was relatively stable feeding 0% to 50% concentrate diets, and it was observed that appropriate concentrate levels in the diet could increase the diversity of rumen bacteria. However, concentrate-rich diets caused lactic acid accumulation and low ruminal pH that caused the disappearance of most fibrolytic-related bacteria sensitive to low pH while S. bovis and genus Prevotella persisted.

show abstract

“…S. cerevisiae produces growth factors for microbial growth that can stimulate rumen microbial growth and activity (Chiquette, 2009). In addition to the ability of S. cerevisiae to provide conducive conditions to microbial growth in a way that is capable of using O2 in the rumen so that the conditions of an aerobic rumen awake (Mosoni et al, 2007). S. cerevisiae.…”

Section: Gas Production Rumen Fermentation and Degradabilitymentioning

confidence: 99%

Effects ofSaccharomyces Cerevisiaeat Direct Addition or Pre-incubation onin VitroGas Production Kinetics and Degradability of Four Fibrous Feeds

Elghandour

Vázquez-Chagoyán

Salem

et al. 2014

Italian Journal of Animal Science

View full text Add to dashboard Cite

The objective of this study was to evaluate the effects of Saccharomyces cerevisiae on in vitro gas production (GP) kinetics and degradability of corn stover, oat straw, sugarcane bagasse and sorghum straw. Feedstuffs were incubated with different doses of yeast [0, 4, 8 and 12 mg/g dry matter (DM)] at direct addition or 72 h pre-incubation. Rumen GP was recorded at 2, 4, 6, 8, 10, 12, 14, 24, 30, 48, 54 and 72 h of incubation. After 72 h, rumen pH and methane were determined and contents were filtrated for DM, neutral (NDF) and acid detergent fibre (ADF) degradability. Fibrous species×method of application×yeast interactions occurred (P<0.001) for all measured ruminal GP parameters and degradability. The direct addition or 72 h pre-incubation of S. cerevisiae with corn stover improved (P<0.05) GP and methane and decreased (P<0.05) the lag time (L) and NDF degradability (NDFD). The direct addition of S. cerevisiae to oat straw increased (P<0.05) rate of GP (c) and decreased (P<0.05) asymptotic GP (b). However, 72 h pre-incubation increased (P<0.05) c with linearly decreased b, DM degradability (DMD) and NDFD. Applying S.cerevisiae for 72 h pre-incubation decreased (P<0.001) methane emission. The direct addition or 72 h pre-incubation of S. cerevisiae to sorghum straw increased (P<0.05) b, c, L, DMD and NDFD. Overall, the effect of dose varied among different feedstuffs and different application methods. Results suggested that the direct addition of S. cerevisiae could support and improve ruminal fermentation of lowquality forages at 4 to 12 g/kg DM.

show abstract

Quantification by real-time PCR of cellulolytic bacteria in the rumen of sheep after supplementation of a forage diet with readily fermentable carbohydrates: effect of a yeast additive

Cited by 161 publications

References 46 publications

Microbial ecosystem and methanogenesis in ruminants

Microbial ecosystem and methanogenesis in ruminants

Rumen chemical and bacterial changes during stepwise adaptation to a high-concentrate diet in goats

Effects ofSaccharomyces Cerevisiaeat Direct Addition or Pre-incubation onin VitroGas Production Kinetics and Degradability of Four Fibrous Feeds

Contact Info

Product

Resources

About