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da Silva ÉBR, da Silva JAR, da Silva WC, Belo TS, Sousa CEL, dos Santos MRP, Neves KAL, Rodrigues TCGDC, Camargo-Júnior RNC, Lourenço-Júnior JDB. A Review of the Rumen Microbiota and the Different Molecular Techniques Used to Identify Microorganisms Found in the Rumen Fluid of Ruminants. Animals (Basel) 2024; 14:1448. [PMID: 38791665 PMCID: PMC11117383 DOI: 10.3390/ani14101448] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 03/13/2024] [Accepted: 03/19/2024] [Indexed: 05/26/2024] Open
Abstract
Variations in environments, including climate, diet, and agricultural practices, significantly impact the composition and microbial activity. A profound understanding of these adaptations allows for the improvement of nutrition and ruminant production. Therefore, this review aims to compile data from the literature on the rumen microbiota and molecular techniques for identifying the different types of microorganisms from the rumen fluid of ruminants. Analyzing the literature on rumen microbiology in different ruminants is complex due to microbial interactions, influenced by the environment and nutrition of these animals. In addition, it is worth noting that the genera of protozoa and fungi most evident in the studies used in this review on the microbiology of rumen fluid were Entodinium spp. and Aspergillus spp., respectively, and Fibrobacter spp. for bacteria. About the techniques used, it can be seen that DNA extraction, amplification, and sequencing were the most cited in the studies evaluated. Therefore, this review describes what is present in the literature and provides an overview of the main microbial agents in the rumen and the molecular techniques used.
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Affiliation(s)
- Éder Bruno Rebelo da Silva
- Postgraduate Program in Animal Science (PPGCAN), Institute of Veterinary Medicine, Federal University of Para (UFPA), Castanhal 68746-360, Brazil; (W.C.d.S.); (T.C.G.d.C.R.); (R.N.C.C.-J.); (J.d.B.L.-J.)
| | | | - Welligton Conceição da Silva
- Postgraduate Program in Animal Science (PPGCAN), Institute of Veterinary Medicine, Federal University of Para (UFPA), Castanhal 68746-360, Brazil; (W.C.d.S.); (T.C.G.d.C.R.); (R.N.C.C.-J.); (J.d.B.L.-J.)
| | - Tatiane Silva Belo
- Department of Veterinary Medicine, University Center of the Amazon (UNAMA), Santarém 68010-200, Brazil; (T.S.B.); (C.E.L.S.)
| | - Carlos Eduardo Lima Sousa
- Department of Veterinary Medicine, University Center of the Amazon (UNAMA), Santarém 68010-200, Brazil; (T.S.B.); (C.E.L.S.)
| | | | | | - Thomaz Cyro Guimarães de Carvalho Rodrigues
- Postgraduate Program in Animal Science (PPGCAN), Institute of Veterinary Medicine, Federal University of Para (UFPA), Castanhal 68746-360, Brazil; (W.C.d.S.); (T.C.G.d.C.R.); (R.N.C.C.-J.); (J.d.B.L.-J.)
| | - Raimundo Nonato Colares Camargo-Júnior
- Postgraduate Program in Animal Science (PPGCAN), Institute of Veterinary Medicine, Federal University of Para (UFPA), Castanhal 68746-360, Brazil; (W.C.d.S.); (T.C.G.d.C.R.); (R.N.C.C.-J.); (J.d.B.L.-J.)
| | - José de Brito Lourenço-Júnior
- Postgraduate Program in Animal Science (PPGCAN), Institute of Veterinary Medicine, Federal University of Para (UFPA), Castanhal 68746-360, Brazil; (W.C.d.S.); (T.C.G.d.C.R.); (R.N.C.C.-J.); (J.d.B.L.-J.)
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Lima J, Ingabire W, Roehe R, Dewhurst RJ. Estimating Microbial Protein Synthesis in the Rumen-Can 'Omics' Methods Provide New Insights into a Long-Standing Question? Vet Sci 2023; 10:679. [PMID: 38133230 PMCID: PMC10747152 DOI: 10.3390/vetsci10120679] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 11/20/2023] [Accepted: 11/22/2023] [Indexed: 12/23/2023] Open
Abstract
Rumen microbial protein synthesis (MPS) provides at least half of the amino acids for the synthesis of milk and meat protein in ruminants. As such, it is fundamental to global food protein security. Estimating microbial protein is central to diet formulation, maximising nitrogen (N)-use efficiency and reducing N losses to the environment. Whilst factors influencing MPS are well established in vitro, techniques for in vivo estimates, including older techniques with cannulated animals and the more recent technique based on urinary purine derivative (UPD) excretion, are subject to large experimental errors. Consequently, models of MPS used in protein rationing are imprecise, resulting in wasted feed protein and unnecessary N losses to the environment. Newer 'omics' techniques are used to characterise microbial communities, their genes and resultant proteins and metabolites. An analysis of microbial communities and genes has recently been used successfully to model complex rumen-related traits, including feed conversion efficiency and methane emissions. Since microbial proteins are more directly related to microbial genes, we expect a strong relationship between rumen metataxonomics/metagenomics and MPS. The main aims of this review are to gauge the understanding of factors affecting MPS, including the use of the UPD technique, and explore whether omics-focused studies could improve the predictability of MPS, with a focus on beef cattle.
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Affiliation(s)
- Joana Lima
- SRUC Dairy Research and Innovation Centre, Barony Campus, Dumfries DG1 3NE, UK; (J.L.); (W.I.)
| | - Winfred Ingabire
- SRUC Dairy Research and Innovation Centre, Barony Campus, Dumfries DG1 3NE, UK; (J.L.); (W.I.)
| | | | - Richard James Dewhurst
- SRUC Dairy Research and Innovation Centre, Barony Campus, Dumfries DG1 3NE, UK; (J.L.); (W.I.)
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Malik PK, Trivedi S, Kolte AP, Mohapatra A, Bhatta R, Rahman H. Effect of an anti-methanogenic supplement on enteric methane emission, fermentation, and whole rumen metagenome in sheep. Front Microbiol 2022; 13:1048288. [PMID: 36478863 PMCID: PMC9719938 DOI: 10.3389/fmicb.2022.1048288] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2022] [Accepted: 11/04/2022] [Indexed: 11/22/2022] Open
Abstract
A study was conducted to investigate the impact of an anti-methanogenic product supplementation on enteric methane emissions, whole rumen metagenome and ruminal fermentation in sheep. Twelve adult male sheep were randomly divided into two groups of six animals each. Animals were fed ad libitum on a total mixed ration either without (CON) or with an anti-methanogenic supplement (Harit Dhara-HD). The anti-methanogenic supplement contained 22.1% tannic acid in a 3: 1 ratio of condensed and hydrolysable tannins. The supplementation of product revealed a significant reduction in daily enteric methane emission (21.9 vs. 17.2 g/d) and methane yield (23.2 vs. 18.2) without affecting the nutrient intake and digestibility. However, the propionate concentration in the HD treatment group was significantly higher than in the CON group. On the contrary, the ammonia nitrogen concentration was lower. The anti-methanogenic supplement significantly decreased the ruminal protozoa in the HD treatment group. Whole rumen metagenome analysis revealed that the core bacterial (Bacteroidetes and Firmicutes) and archaeal communities (Methanobrevibacter and Methanosarcina) were comparable between the CON and HD treatment groups. However, the supplementation of anti-methanogenic product led to a considerable reduction in the abundance of Proteobacteria, whereas the abundance of Lentisphaerae was greater. The supplementation significantly decreased the abundance of Methanocaldococcus, Methanococcoides, Methanocella, and Methanoregula methanogens. A total of 36 KO related to methanogenesis were identified in this study. The activities of formate dehydrogenase (EC 1.8.98.6) and tetrahydromethanopterin S-methyltransferase (EC 2.1.1.86) were significantly lowered by the anti-methanogenic product supplementation in sheep. In conclusion, the anti-methanogenic supplement has the potential to decrease enteric methane emission (~22%) at the recommended level (5% of DM) of supplementation. The contribution of minor methanogens vulnerable to supplementation to rumen methanogenesis is not known; hence, the culturing of these archaea should be taken on priority for determining the impact on overall rumen methanogenesis.
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Affiliation(s)
- Pradeep Kumar Malik
- ICAR-National Institute of Animal Nutrition and Physiology, Bangalore, India
| | | | - Atul Purushottam Kolte
- ICAR-National Institute of Animal Nutrition and Physiology, Bangalore, India,*Correspondence: Atul Purushottam Kolte,
| | - Archit Mohapatra
- ICAR-National Institute of Animal Nutrition and Physiology, Bangalore, India
| | - Raghavendra Bhatta
- ICAR-National Institute of Animal Nutrition and Physiology, Bangalore, India
| | - Habibar Rahman
- International Livestock Research Institute, New Delhi, India
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Henniger MT, Wells JE, Hales KE, Lindholm-Perry AK, Freetly HC, Kuehn LA, Schneider LG, McLean KJ, Campagna SR, Christopher CJ, Myer PR. Effects of a Moderate or Aggressive Implant Strategy on the Rumen Microbiome and Metabolome in Steers. FRONTIERS IN ANIMAL SCIENCE 2022. [DOI: 10.3389/fanim.2022.889817] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
The effects of growth-promoting implants have been well-defined for their ability to impact growth performance in beef cattle. Production-relevant microbes and microbiomes in the rumen have also been associated with growth traits. However, the role of implants on the rumen microbiome has not been determined. The objective of this study was to determine if different doses of implant hormones cause gain-associated ruminal microbial community changes. To assess this, a completely randomized design was used and 336 fall-born steers 450 to 470 days of age from the germplasm evaluation population at the US Meat Animal Research Center (Clay Center, NE) were divided into two treatment groups: 1) a moderate implant strategy (n = 167) of Revalor-IS (80 mg trenbolone acetate and 16 mg estradiol) followed by Revalor-S (120 mg trenbolone acetate and 24 mg estradiol) or 2) an aggressive implant strategy (n = 169) of Revalor-IS followed by Revalor-200 (200 mg trenbolone acetate and 20 mg estradiol). Steers were fed the same diet (57.0% dry-rolled corn, 30% wet distiller’s grains with solubles, 8.0% alfalfa hay, 4.25% vitamin and mineral supplement, and 0.75% urea, on a DM basis). On d 85 after implants administration, rumen contents were collected via orogastric tubing. Samples were sequenced to target and identify bacteria, archaea, and protozoa. Untargeted metabolomics was performed on rumen content using ultra high performance liquid chromatography high resolution mass spectrometry. Production data between implant strategies was analyzed using a mixed model ANOVA (SASv9.4, Cary, NC) followed by separation of least squares means. Microbial diversity between strategies did not differ for archaea or protozoa (P > 0.05). Average daily gain was different (P = 0.01; 1.72 vs 1.66 ± 0.02 kg, aggressive vs moderate, respectively); however, large microbial community shifts were not associated with implant strategy. Two metabolites, N-acetyllysine and N-acetylornithine, were found in greater abundance in the moderate implant strategy (P ≤ 0.04). Understanding associations between the rumen microbiome and implant strategies may allow improvement of growth efficiency in beef cattle.
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Ruminal Protozoal Populations of Angus Steers Differing in Feed Efficiency. Animals (Basel) 2021; 11:ani11061561. [PMID: 34071838 PMCID: PMC8229867 DOI: 10.3390/ani11061561] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2021] [Revised: 05/21/2021] [Accepted: 05/24/2021] [Indexed: 11/17/2022] Open
Abstract
Simple Summary The rumen protozoa have been demonstrated to enhance methanogenesis and impact intraruminal recycling of microbial protein. However, they are also known to contribute to fiber degradation and the stabilization of ruminal pH changes. The apparent metabolic impact of ciliated protozoa in the rumen may contribute to the variation in feed efficiency. This study examined the relationship between the rumen protozoa and feed efficiency in beef steers. We monitored feed intake and body weight for a 70-day feed efficiency trial. Following the trial, rumen content was collected, protozoal DNA was extracted from the content, and the relationship between protozoa community diversity and species abundance with feed efficiency was examined. The ciliated protozoal community diversity differed between low- and high-feed efficient steers. Greater abundances of unidentified protozoa genera were detected in the low-feed efficient steers. These data suggest that unidentified protozoa and ciliated protozoal community diversity influence feed efficiency in beef steers. Abstract Feed accounts for as much as 70% of beef production costs, and improvement of the efficiency with which animals convert feed to product has the potential to have substantial financial impact on the beef industry. The rumen microbiome plays a key role in determining feed efficiency; however, previous studies of rumen microbiota have not focused on protozoal communities despite the estimation that these organisms represent approximately 50% of rumen content biomass. Protozoal communities participate in the regulation of bacterial populations and nitrogen cycling—key aspects of microbiome dynamics. The present study focused on identifying potential associations of protozoal community profiles with feed efficiency. Weaned steers (n = 50) 7 months of age weighing approximately 260 kg were adapted to a growing ration and GrowSafe for 2 weeks prior to a 70-day feed efficiency trial. The GrowSafe system is a feeding system that monitors feed intake in real time. Body weights were collected on the first day and then every 7 days of the feed efficiency trial, and on the final day, approximately 50 mL of rumen content were collected via orogastric tubing and frozen at −80 °C. Body weight and feed intake were used to calculate residual feed intake (RFI) as a measure of feed efficiency, and steers were categorized as high (n = 14) or low (n = 10) RFI based on ±0.5 standard deviations about the mean RFI. Microbial DNA was extracted, and the eukaryotic component profiled by amplification and sequencing of 18S genes using degenerate primers that can amplify this locus across a range of protists. The taxonomy of protozoal sequences was assigned using QIIME 1.9 and analyzed using QIIME and SAS 9.4 with significance determined at α ≤ 0.05. Greater abundances of unassigned taxa were associated with high-RFI steers (p = 0.03), indicating a need for further study to identify component protozoal species. Differences were observed between low- and high-RFI steers in protozoal community phylogenetic diversity, including weighted beta-diversity (p = 0.04), Faith’s phylogenetic diversity (p = 0.03), and observed Operational taxonomic unit (OTU) (p = 0.03). The unassigned taxa and differences in phylogenetic diversity of protozoal communities may contribute to divergences observed in feed efficiency phenotypes in beef steers.
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Duarte ER, Abrão FO, Oliveira Ribeiro IC, Vieira EA, Nigri AC, Silva KL, Virgínio Júnior GF, Prates Barreto SM, Geraseev LC. Rumen protozoa of different ages of beef cattle raised in tropical pastures during the dry season. JOURNAL OF APPLIED ANIMAL RESEARCH 2018. [DOI: 10.1080/09712119.2018.1530676] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
Affiliation(s)
- Eduardo Robson Duarte
- Instituto de Ciências Agrárias, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | | | - Edvaldo Alves Vieira
- Instituto de Ciências Agrárias, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Ana Carolina Nigri
- Instituto de Ciências Agrárias, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | - Kellerson Luiz Silva
- Instituto de Ciências Agrárias, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
| | | | | | - Luciana Castro Geraseev
- Instituto de Ciências Agrárias, Universidade Federal de Minas Gerais, Belo Horizonte, Brazil
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Nigri A, Ribeiro I, Vieira E, Silva M, Virgínio-Júnior G, Abrão F, Geraseev L, Duarte E. População de protozoários ruminais em novilhos zebuínos alimentados com ou sem volumoso. ARQ BRAS MED VET ZOO 2017. [DOI: 10.1590/1678-4162-9009] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Affiliation(s)
| | | | | | - M.L.F. Silva
- Universidade Estadual do Sudoeste da Bahia, Brazil
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Effects of maize and citrus-pulp supplementation of urea-treated wheat straw on intake and productivity in female lambs. ACTA ACUST UNITED AC 2016. [DOI: 10.1017/s1357729800058124] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
AbstractTwo experiments with lambs given food indoors and individually penned were designed to study the effects of different levels of ground maize and citrus pulp as supplements of a diet based on urea-treated straw (5 kg urea per 100 kg straw) offered ad libitum over a period of 16 weeks (experiment 1) or 10 weeks (experiment 2). The voluntary intake, live-weight gain (LWG), organic matter digestibility (OMD), urinary allantoin-nitrogen (UAN) excretion and acetate clearance rate were measured. The lambs were blocked on weight and randomly assigned to the treatments described below. Ruminal outflow rate of the solid and liquid phases from the rumen were also measured in experiment 2.In experiment 1, 20 female lambs from the Ile-de-France breed, with an initial live weight (LW) of 43 (s.e. 3·3) kg were used. Wheat straw (WS) was supplemented with 50 g/kg of fish meal (FM) and with 0, 100, 200 or 300 g/kg of ground maize on a dry-matter (DM) basis (M0, M1, M2 and M3, respectively). In experiment 2, 25 female lambs from the Portuguese breed Churra-da-Terra-Quente, with an initial LW of 24·2 (s.e. 4·3) kg were used. The straw was offered ad libitum during 10 weeks and supplemented with 50 g/kg of FM and 0, 100, 200, 300, or 400 g/kg of dried citrus pulp on a DM basis (CP0, CP1, CP2, CP3 and CP4, respectively).During the experiments, all animals were moved to metabolism cages to measure OMD and UAN excretion. Two additional incubation studies were carried out with rumen fistulated rams (experiment 1) or cows (experiment 2) given the diets described above close to the maintenance feeding level.In experiment 1 daily straw DM intake linearly decreased (P < 0·05) from 21·6 to 17·7 g/kg LW and LWG linearly increased (P < 0·05) from 51 to 154 g/day for treatments M0, M1, M2 and M3, respectively. The rate of straw DM degradation was significantly decreased (P < 0·01) by maize supplementation. Straw OMD (kg/kg) was 0·562, 0·583, 0·547 and 0·520 and UAN (mg/day) was 620, 790, 854 and 859 for treatments M0, M1, M2 and M3, respectively. Acetate clearance rate, increased (P < 0·05) as the level of maize inclusion increased.In experiment 2 daily straw DM intake was 23·3, 25·8, 24·7, 23·5 and 18·6 g/kg LW per day and LWG was –9, 28, 44, 64 and 67 g/day for treatments CP0, CP1, CP2, CP3 and CP4, respectively. Supplementation significantly increased LWG (P < 0·001) but at the 400 g/kg level depressed straw DM intake. Straw OMD linearly decreased (P < 0·05) from 0·484 (CP0) to 0·428 (CP4) g/kg and UAN (mg/day) was 181, 303, 363, 384 and 392 for treatments CP0, CP1, CP2, CP3 and CP4, respectively. Rumen outflow rate of fibre particles was unaffected by supplementation while the outflow of liquid phase tended to be increased (P < 0·10). The rate of DM degradation was significantly reduced (P < 0·01) by citrus-pulp inclusion. Acetate clearance rate was unaffected (P > 0·05) by citrus-pulp supplementation.The results of these experiments demonstrate that supplementation of urea-treated straw with ground maize up to 200 g/kg or with citrus pulp up to 300 g/kg of the diet DM increased or did not depress straw intake, increased the supply of microbial protein and have no significant effect on straw digestibility. The efficiency of utilization of absorbed energy was apparently improved by maize but not by citrus-pulp supplementation.
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Miltko R, Bełżecki G, Herman A, Kowalik B, Skomiał J. The effect of rumen ciliates on chitinolytic activity, chitin content and the number of fungal zoospores in the rumen fluid of sheep. Arch Anim Nutr 2016; 70:425-40. [PMID: 27501267 DOI: 10.1080/1745039x.2016.1215695] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
Abstract
The objective of this study was to investigate the effect of selected protozoa on the degradation and concentration of chitin and the numbers of fungal zoospores in the rumen fluid of sheep. Three adult ewes were fed a hay-concentrate diet, defaunated, then monofaunated with Entodinium caudatum or Diploplastron affine alone and refaunated with natural rumen fauna. The average density of the protozoa population varied from 6.1 · 10(4) (D. affine) to 42.2 · 10(4) cells/ml rumen fluid (natural rumen fauna). The inoculation of protozoa in the rumen of defaunated sheep increased the total activity of chitinolytic enzymes from 2.9 to 3.6 μmol N-acetylglucosamine/g dry matter (DM) of rumen fluid per min, the chitin concentration from 6.3 to 7.2 mg/g DM of rumen fluid and the number of fungal zoospores from 8.1 to 10.9 · 10(5) cells/ml rumen fluid. All examined indices showed diurnal variations. Ciliate population density was highest immediately prior to feeding and lowest at 4 h thereafter. The opposite effects were observed for the numbers of fungal zoospores, the chitin concentration and chitinolytic activity. Furthermore, it was found that chitin from zoospores may account for up to 95% of total microbial chitin in the rumen fluid of sheep. In summary, the examined ciliate species showed the ability of chitin degradation as well as a positive influence on the development of the ruminal fungal population.
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Affiliation(s)
- Renata Miltko
- a The Kielanowski Institute of Animal Physiology and Nutrition , Polish Academy of Sciences , Jabłonna , Poland
| | - Grzegorz Bełżecki
- a The Kielanowski Institute of Animal Physiology and Nutrition , Polish Academy of Sciences , Jabłonna , Poland
| | - Andrzej Herman
- a The Kielanowski Institute of Animal Physiology and Nutrition , Polish Academy of Sciences , Jabłonna , Poland
| | - Barbara Kowalik
- a The Kielanowski Institute of Animal Physiology and Nutrition , Polish Academy of Sciences , Jabłonna , Poland
| | - Jacek Skomiał
- a The Kielanowski Institute of Animal Physiology and Nutrition , Polish Academy of Sciences , Jabłonna , Poland
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Newbold CJ, de la Fuente G, Belanche A, Ramos-Morales E, McEwan NR. The Role of Ciliate Protozoa in the Rumen. Front Microbiol 2015; 6:1313. [PMID: 26635774 PMCID: PMC4659874 DOI: 10.3389/fmicb.2015.01313] [Citation(s) in RCA: 301] [Impact Index Per Article: 33.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2015] [Accepted: 11/09/2015] [Indexed: 01/17/2023] Open
Abstract
First described in 1843, Rumen protozoa with their striking appearance were assumed to be important for the welfare of their host. However, despite contributing up to 50% of the bio-mass in the rumen, the role of protozoa in rumen microbial ecosystem remains unclear. Phylogenetic analysis of 18S rDNA libraries generated from the rumen of cattle, sheep, and goats has revealed an unexpected diversity of ciliated protozoa although variation in gene copy number between species makes it difficult to obtain absolute quantification. Despite repeated attempts it has proven impossible to maintain rumen protozoa in axenic culture. Thus it has been difficult to establish conclusively a role of ciliate protozoa in rumen fiber degradation. The development of techniques to clone and express ciliate genes in λ phage, together with bioinformatic indices to confirm the ciliate origin of the genes has allowed the isolation and characterization of fibrolytic genes from rumen protozoa. Elimination of the ciliate protozoa increases microbial protein supply by up to 30% and reduces methane production by up to 11%. Our recent findings suggest that holotrich protozoa play a disproportionate role in supporting methanogenesis whilst the small Entodinium are responsible for much of the bacterial protein turnover. As yet no method to control protozoa in the rumen that is safe and practically applicable has been developed, however a range of plant extract capable of controlling if not completely eliminating rumen protozoa have been described.
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Affiliation(s)
- Charles J. Newbold
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK
| | - Gabriel de la Fuente
- Departament de Producció Animal, Escola Tècnica Superior d’Enginyeria Agrària, Universitat de Lleida, Lleida, Spain
| | - Alejandro Belanche
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK
| | - Eva Ramos-Morales
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK
| | - Neil R. McEwan
- Institute of Biological Environmental and Rural Sciences, Aberystwyth University, Aberystwyth, UK
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Belanche A, Abecia L, Holtrop G, Guada JA, Castrillo C, de la Fuente G, Balcells J. Study of the effect of presence or absence of protozoa on rumen fermentation and microbial protein contribution to the chyme1. J Anim Sci 2011; 89:4163-74. [DOI: 10.2527/jas.2010-3703] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Abstract
Anaerobic chytridiomycete fungi are found in the gastrointestinal tracts of sheep, cattle and goats, as well as in many other domesticated ruminant and nonruminant herbivores and a wide variety of wild herbivorous mammals. They are principally found associated with the fibrous plant particles of digesta and as free swimming zoospores in the fluid phase. The presence of large fungal populations in animals consuming mature pasture or diets largely composed of hay or straw together with the production of highly active fibre degrading enzymes lead to' the belief that anaerobic fungi may have a significant role to play in the assimilation of fibrous feeds by ruminants. While many early studies focused on anaerobic fungi because of their unusual biology and metabolism, the large part of subsequent research has emphasized the biotechnological potential of their cellulases, xylanases and phenolic esterases. In recent years, the extent of the contribution of anaerobic fungi to the nutrition of ruminants has also been established through studies of fungal populations in the rumen and the dietary factors which influence them, as presented in this review. Further, we discuss the evidence supporting an important contribution of anaerobic fungal populations in the rumen to feed intake and digestion of poor quality feed by domesticated ruminants. In conclusion, the review explores some different methods for manipulating fungi in the rumen for increased feed intake and digestion.
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Affiliation(s)
- G L Gordon
- Commonwealth Scientific and Industrial Research Organisation, Division of Animal Production, Locked Bag 1, Delivery Centre, Blacktown, New South Wales 2148, Australia
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Muetzel S, Lawrence P, Hoffmann EM, Becker K. Evaluation of a stratified continuous rumen incubation system. Anim Feed Sci Technol 2009. [DOI: 10.1016/j.anifeedsci.2008.11.001] [Citation(s) in RCA: 29] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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Dijkstra J, Mills JAN, France J. The role of dynamic modelling in understanding the microbial contribution to rumen function. Nutr Res Rev 2009; 15:67-90. [DOI: 10.1079/nrr200237] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Effects of the absence of protozoa from birth or from weaning on the growth and methane production of lambs. Br J Nutr 2008; 100:1220-7. [PMID: 18479584 DOI: 10.1017/s0007114508981435] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Merino ewes (n 108) joined to a single sire were allocated into three flocks, with ewes in one flock being chemically defaunated in the second month of gestation. Single lambs born to defaunated ewes (BF lambs) were heavier at birth and at weaning than lambs born to faunated ewes (F lambs). After weaning, all BF and F lambs were individually housed then half of the F lambs were chemically defaunated (DF lambs). In trial 1, BF, DF and F lambs were offered a concentrate-based diet containing either 14 or 19 % protein for a 10-week period. Wool growth rate of BF lambs was 10 % higher than that of DF or F lambs and was increased 9 % by the high-protein diet. While there was no main effect of protozoa treatment on enteric methane production, there was an interaction between protozoa treatment and diet for methane production. BF and DF lambs produced more methane than F lambs when fed the low-protein diet but when fed the high-protein diet, emissions were less than (BF lambs) or not different from (DF lambs) emissions from F lambs. In trial 2, lambs were offered 800 g roughage per d and, again, methane production was not affected by the presence of protozoa in the rumen. The data indicate that while lambs without rumen protozoa have greater protein availability than do faunated ruminants, there is no main effect of rumen protozoa on enteric methane production by lambs fed either a concentrate or roughage diet.
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Eugène M, Archimède H, Sauvant D. Quantitative meta-analysis on the effects of defaunation of the rumen on growth, intake and digestion in ruminants. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/s0301-6226(03)00117-9] [Citation(s) in RCA: 85] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Devillard E, Newbold CJ, Scott KP, Forano E, Wallace RJ, Jouany JP, Flint HJ. A xylanase produced by the rumen anaerobic protozoan Polyplastron multivesiculatum shows close sequence similarity to family 11 xylanases from gram-positive bacteria. FEMS Microbiol Lett 1999; 181:145-52. [PMID: 10564800 DOI: 10.1111/j.1574-6968.1999.tb08837.x] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
Abstract
We report for the first time the cloning and characterisation of a protozoal enzyme involved in plant cell wall polysaccharide degradation. A cDNA library was constructed from the ruminal protozoan Polyplastron multivesiculatum and a stable clone expressing xylanase activity was isolated. The encoded enzyme belongs to the glycoside hydrolase family 11, and phylogenetic analysis indicates a closer relationship with catalytic domains from Gram-positive bacteria than the other fibrolytic eukaryotes from the rumen, the anaerobic fungi.
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Affiliation(s)
- E Devillard
- Rowett Research Institute, Bucksburn, Aberdeen, UK
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Use of ratio of digested xylan to digested cellulose (X/C) as an index of fiber digestion in plant cell-wall material by ruminal microorganisms. Anim Feed Sci Technol 1998. [DOI: 10.1016/s0377-8401(97)00164-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Chaudhary L, Srivastava A, Singh K. Rumen fermentation pattern and digestion of structural carbohydrates in buffalo (Bubalus bubalis) calves as affected by ciliate protozoa. Anim Feed Sci Technol 1995. [DOI: 10.1016/0377-8401(95)00810-a] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Dijkstra J, Tamminga S. Simulation of the effects of diet on the contribution of rumen protozoa to degradation of fibre in the rumen. Br J Nutr 1995; 74:617-34. [PMID: 8541269 DOI: 10.1079/bjn19950166] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
Abstract
A previously described mathematical model, that stimulates the metabolic activities of rumen bacteria and protozoa, was used to examine the contribution of protozoa to neutral-detergent fibre (NDF) degradation in the rumen of cattle. Comparisons between predicted and experimentally observed NDF degradation showed general agreement. Further simulations were performed with diets containing variable proportions of concentrate (between 0 and 1 kg/kg diet DM) and at intake levels ranging between 5.3 and 21.0 kg DM/d. The simulated protozoal contribution to NDF degradation was 17-21% at the lowest intake level. Except for the all-concentrate diets, raising the feed intake level reduced this contribution to 5-13% at the highest intake level. The changes in contribution of protozoa to NDF degradation were related to variations in the fibrolytic bacteria: protozoa value and the NDF-degrading activities of protozoa predicted by the model. In simulations where dietary NDF levels were reduced and starch and sugar levels were increased independently, protozoal contribution to NDF degradation generally increased. These differences were reflected also in the generally increased protozoal contribution to NDF degradation predicted in response to a decreased roughage:concentrate value. The contribution of protozoa also generally declined in response to added N. These changes in predicted protozoal contribution to NDF degradation resulting from dietary variations provided possible explanations for the differences in rumen NDF degradation observed when animals are defaunated.
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Affiliation(s)
- J Dijkstra
- Institute of Grassland and Environmental Research, North Wyke Research Station, Okehampton, Devon
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Chaudhary L, Srivastava A. Performance of growing Murrah buffalo calves as affected by treatment with Manoxol and the presence of ciliate protozoa in the rumen. Anim Feed Sci Technol 1995. [DOI: 10.1016/0377-8401(94)00689-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/01/2022]
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Abstract
Different methods of optimizing feed conversion into nutrients in the rumen are now available to scientists. But the rumen must be considered as an integrated system and this makes it difficult to rationalize manipulation. The observed result of any treatment is a combination of several interactive reactions. Any change to one component of the system has several uncontrolled effects on other components. The positive effects aimed for are sometimes associated with undesirable effects. Numerous chemical additives have been studied during the last two decades among which ionophore antibiotics represent the most important group. The interest of non-ionophore antibiotics, methane inhibitors, and compounds inhibiting proteases or deaminases, has also been considered during the last years. The observed effects of these chemical additives on animals, and their possible mode of action on rumen microbes and on animal metabolism, are discussed. However, the risks of the presence of residues in meat and milk are questioned by consumers. Microbial activity in the rumen can be altered by feeding animals with large amounts of certain food constituents (fats, starch) or minerals (buffer substances). The responses in the rumen to these dietary conditions are analyzed in terms of the digestive effects on plant cell wall degradation and microbial protein synthesis. Modification of the rumen microbial population is now considered as a possible approach to rumen manipulation by scientists. The effects on digestion of the elimination of ciliate protozoa (defaunation) are presented. The feasibility of these objectives, from a practical standpoint, is discussed. Finally, there is an overview of the effects of the addition of live yeasts (Saccharomyces cerevisciae), or fungi (Aspergillus orizae), used as probiotics. A possible mode of action of probiotics on the rumen ecosystem is suggested.
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Affiliation(s)
- J P Jouany
- I.N.R.A., Centre de Recherches de Clermont-Ferrand/Theix, France
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Kayouli C, Jouany J, Demeyer D, Ali-Ali, Taoueb H, Dardillat C. Comparative studies on the degradation and mean retention time of solid and liquid phases in the forestomachs of dromedaries and sheep fed on low-quality roughages from Tunisia. Anim Feed Sci Technol 1993. [DOI: 10.1016/0377-8401(93)90063-p] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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