On the Lebesgue measure, Hausdorff dimension, and Fourier dimension of sums and products of subsets of Euclidean space

We investigate the Lebesgue measure, Hausdorff dimension, and Fourier dimension of sets of the form $RY +Z,$ where $R \subseteq (0,\infty)$ and $Y, Z \subset \mathbb{R}^d$. Most notable, for each $\alpha \in [0,1]$ and for each non-empty set $Y \subseteq \mathbb{R}$, we prove the existence of a compact set $R \subseteq (0,\infty)$ such that $\dim_H(R) = \dim_F(R) = \alpha$ and $\dim_F(RY) \geq \min\{ 1, \dim_F(R) + \dim_F(Y)\}$. This work is a contribution to the set of problems which study the measure and dimension of images of subsets of Euclidean space under Lipschitz maps

Influence of processing method of rumen contents on microbial populations in the inoculum and in vitro fermentation of substrates of variable composition

The in vitro batch culture technique is being increasingly used to study rumen fermentation, but the results are affected by several factors, being the source of the inoculum one of the most relevant. This work was conducted to assess the effects of different processing methods of ruminal contents on microbial populations in the obtained fluid, and its influence on fermentation parameters when the fluid was used as inoculum for in vitro incubations. Rumen contents were obtained from four rumen-fistulated sheep fed a 2:1 alfalfa hay:concentrate diet and subjected to the following treatments: SQ: squeezed through four layers of cheesecloth; FL: SQ treatment and further filtration through a 100-μm nylon cloth; STO: blended for three min at 230 rev min−1 in a Stomacher® and further filtrations as in SQ. Microbial populations’ abundance and bacterial diversity in the ruminal fluids were analysed by quantitative PCR (qPCR) and automated ribosomal intergenic spacer analysis (ARISA), respectively. Three forages (alfalfa hay, grass hay and barley straw) were incubated in vitro, either alone or mixed with concentrate (1:1), using each of the ruminal fluids as inoculum. There were no differences between SQ and FL methods in any of the microbial populations analysed, but STO increased the relative abundance of Fibrobacter succinogenes and Ruminococcus albus (P 0.05) by the processing methods. There were no interactions (P > 0.05) between the processing method and the characteristics of the substrates for any of the fermentation parameters analysed. Compared with SQ, the STO method resulted in greater (P < 0.05) methane production and ammonia-N concentrations in 8 h incubations. After 24 h of incubation, the use of STO inoculum increased (P < 0.05) methane production and dry matter degradability compared with SQ, with no differences in the rest of the parameters. No differences between SQ and FL methods were detected in any parameter. The results show that stomaching the rumen contents prior to inoculation of in vitro cultures modified some microbial populations, but had only subtle effects on fermentation parameters

Influence of inoculum type (ileal, caecal and faecal) on the in vitro fermentation of different sources of carbohydrates in rabbits

[EN] Two in vitro experiments were performed to analyse the fermentative potential of ileal content, caecal content, soft faeces and hard faeces from adult rabbits. Experiment 1 evaluated 3 doses (0.5, 1.0 and 2.0 g fresh digesta/g substrate dry matter [DM]) of ileal and caecal digesta as inoculum in 28 h-incubations. Two ileal and 2 caecal inocula were obtained, each by pooling the ileal or caecal digesta of 2 adult rabbits. Pectin from sugar beet pulp (SBP) and the insoluble residue obtained after a 2-step in vitro pre-digestion of SBP and wheat straw were used as substrates. The 0.5 dose produced the lowest (P0.05) between the 1.0 and 2.0 doses (44.9, 51.6 and 53.8 mL/g substrate DM, respectively; values averaged across inocula and substrates). Experiment 2 evaluated two doses of ileal inoculum (1 and 1.5 g fresh digesta/g substrate DM) and compared ileal digesta, caecal digesta, soft faeces and hard faeces as inoculum for determining in vitro gas production (144-h incubations) of the 3 substrates used in Experiment 1 and wheat starch. Three inocula of each type were obtained, each by pooling either digesta or faeces from 3 rabbits. There were no differences (P>0.05) between the 2 ileal doses tested in gas production parameters, and therefore the 1.0 dose was selected for further ileal fermentations. Starch and pectin showed similar (P>0.05) values of gas production rate and maximal gas production rate when they were fermented with caecal digesta (0.038 vs. 0.043%/h, and 13.7 vs. 15.2 mL/h, respectively), soft (0.022 vs. 0.031%/h, and 9.97 vs. 9.33 mL/h) and hard faeces (0.031 vs. 0.038%/h, and 13.6 vs. 10.8 mL/h), and values were higher than those for SBP and wheat straw; in contrast, values for starch and pectin differed with the ileal inoculum (0.046 vs. 0.024%/h, and 18.4 vs. 6.60 mL/h). Both ileal and caecal gas production parameters were well correlated with those for hard and soft faeces inocula, respectively (r≥0.77; P≤0.040). The ileal inoculum showed a relevant fermentative potential, but lower than that of caecal digesta and soft and hard faeces for all substrates except wheat starch.Funding from the Spanish Ministry of Economy and Competitiveness (Project AGL2011-22628) and the Comunidad Autónoma de Madrid (CAM; Project MEDGAN ABI-2913) is gratefully acknowledged.Abad-Guamán, R.; Larrea-Dávalos, JA.; Carabaño, R.; García, J.; Carro, MD. (2018). Influence of inoculum type (ileal, caecal and faecal) on the in vitro fermentation of different sources of carbohydrates in rabbits. World Rabbit Science. 26(3):227-240. https://doi.org/10.4995/wrs.2018.9726SWORD227240263Abad R., Ibañez M.A., Carabaño R., García J. 2013. Quantification of soluble fibre in feedstuffs for rabbits and evaluation of the interference between the determinations of soluble fibre and intestinal mucin. Anim. Feed Sci. Tech., 182: 61-70. https://doi.org/10.1016/j.anifeedsci.2013.04.001Abad-Guamán R., Carabaño R., Gómez-Conde M.S., García J. 2015. Effect of type of fiber, site of fermentation, and method of analysis on digestibility of soluble and insoluble fiber in rabbits. J. Anim. Sci., 93: 2860-2871. https://doi.org/10.2527/jas.2014-8767Association of Official Analytical Chemists International. 2000. Official Methods of Analysis 17th ed. AOAC International, Washington, DC.Bindelle J., Buldgen A., Lambotte D., Wavreille J., Leterme P. 2007. Effect of pig faecal donor and of pig diet composition on in vitro fermentation of sugar beet pulp. Anim. Feed Sci. Technol., 132: 212-226. https://doi.org/10.1016/j.anifeedsci.2006.03.010Boletín Oficial del Estado (BOE). 2013. Royal Decree 53/2013 of February 1st on the protection of animals used for experimentation or other scientific purposes. BOE nº 34, 11370-11421. https://www.boe.es/boe/dias/2013/02/08/pdfs/BOE-A-2013-1337.pdf Accessed January 2017. In Spanish.Bovera F., Calabro S., Cutrignelli M.I., Infascelli F., Piccolo G., Nizza S., Tudisco R., Nizza A. 2008. Prediction of rabbit caecal fermentation characteristics from faeces by in vitro gas production technique: roughages. J. Anim. Physiol. Anim. Nutr., 92: 260-271. https://doi.org/10.1111/j.1439-0396.2007.00748.xBovera F., D'Urso S., Di Meo C., Piccolo G., Calabro S., Nizza A. 2006. Comparison of rabbit caecal content and rabbit hard faeces as source of inoculum for the in vitro gas production technique. Asian Austral. J. Anim. Sci., 19: 1649-1657. https://doi.org/10.5713/ajas.2006.1649Bovera F., D'Urso S., Meo C.D., Tudisco R., Nizza A. 2009. A model to assess the use of caecal and faecal inocula to study fermentability of nutrients in rabbit. J. Anim. Physiol. Anim. Nutr., 93: 147-156. https://doi.org/10.1111/j.1439-0396.2007.00795.xCalabrò S., Nizza A., Pinna W., Cutrignelli M., Piccolo V. 1999. Estimation of digestibility of compound diets for rabbits using the in vitro gas production technique. World Rabbit Sci., 7: 197-201. https://doi.org/10.4995/wrs.1999.401Carabaño R., Fraga M.J., Santoma G., de Blas C. 1988. Effect of diet on composition of cecal contents and on excretion and composition of soft and hard feces of rabbits. J. Anim. Sci 66: 901-1000. https://doi.org/10.2527/jas1988.664901xCarabaño R., García J., de Blas J.C. 2001. Effect of fibre source on ileal apparent digestibility of non-starch polysaccharides in rabbits. Anim. Sci., 72: 343-350. https://doi.org/10.1017/S1357729800055843Falcão-e-Cunha L., Peres H., Freire J.P.B., Castro-Solla L. 2004. Effects of alfalfa, wheat bran or beet pulp, with or without sunflower oil, on caecal fermentation and on digestibility in the rabbit. Anim. Feed Sci. Technol., 117: 131-149. https://doi.org/10.1016/j.anifeedsci.2004.07.014García J., Carabaño R., de Blas J.C. 1999. Effect of fiber source on cell wall digestibility and rate of passage in rabbits. J. Anim. Sci., 77: 898-905. https://doi.org/10.2527/1999.774898xGarcía J., Carabaño R., Pérez-Alba L., de Blas J.C. 2000. Effect of fiber source on cecal fermentation and nitrogen recycled through cecotrophy in rabbits. J. Anim. Sci., 78: 638-646. https://doi.org/10.2527/2000.783638xGarcía J., Gidenne T., Falcão-e-Cunha L., de Blas C. 2002. Identification of the main factors that influence caecal fermentation traits in growing rabbits. Anim. Res. 51: 165-173. https://doi.org/10.1051/animres:2002011Gidenne T. 1992. Effect of fiber level, particle-size and adaptation period on digestibility and rate of passage as measured at the ileum and in the feces in the adult-rabbit. Brit. J. Nutr., 67: 133-146. https://doi.org/10.1079/BJN19920015Gidenne T. 1994. Effect of a reduction in fiber content on the rate of passage through the digestive-tract of the rabbit-comparison of models for the fecal kinetics of 2 markers. Reprod. Nutr. Dev., 34: 295-307. https://doi.org/10.1051/rnd:19940403Goering H.K., Van Soest P.J. 1970. Forage Fiber Analysis (Apparatus, Reagents, Procedures, and Some Applications). USDA Agricultural Research Service, Handbook, Washington, DC.Gouet P., Fonty G. 1979. Changes in the digestive microflora of holoxenic rabbits from birth until adulthood. Ann. Biol Anim. Bioch., 19: 553-566. https://doi.org/10.1051/rnd:19790501Littell R.C., Henry P.R., Ammerman C.B. 1998. Statistical analysis of repeated measures data using SAS procedures. J. Anim. Sci., 76: 1216-1231. https://doi.org/10.2527/1998.7641216xMarounek M., Vovk S.J., Skrivanova V. 1995. Distribution of activity of hydrolytic enzymes in the digestive-tract of rabbits. Brit. J. Nutr., 73: 463-469. https://doi.org/10.1079/BJN19950048Menke K.H., Raab L., Salewski A., Steingass H., Fritz D., Schneider W. 1979. The estimation of the digestibility and metabolizable energy of ruminant feedingstuff from the gas production when they are incubated with rumen liquor in vitro. J. Agr. Sci., 93: 217-222. https://doi.org/10.1017/S0021859600086305Mertens D.R., Allen M., Carmany J., Clegg J., Davidowicz A., Drouches M., Frank K., Gambin D., Garkie M., Gildemeister B., Jeffress D., Jeon C.S., Jones D., Kaplan D., Kim G.N., Kobata S., Main D., Moua X., Paul B., Robertson J., Taysom D., Thiex N., Williams J., Wolf M. 2002. Gravimetric determination of amylase-treated neutral detergent fiber in feeds with refluxing in beakers or crucibles: Collaborative study. J. AOAC Int., 85:1217-1240.Mould F.L., Kliem K.E., Morgan R., Mauricio R.M. 2005. In vitro microbial inoculum: A review of its function and properties. Anim. Feed Sci. Tech., 123: 31-50. https://doi.org/10.1016/j.anifeedsci.2005.04.028Murray S.M., Flickinger E.A., Patil A.R., Merchen N.R., Brent J.L., Fahey G.C. 2001. In vitro fermentation characteristics of native and processed cereal grains and potato starch using ileal chyme from dogs. J. Anim. Sci., 79: 435-444. https://doi.org/10.2527/2001.792435xOmed H.M., Lovett D.K., Axford R.F.E. 2000. Faeces as a source of microbial enzymes for estimating digestibility, In: Givens D., Owen E., Axford R., Omed H. (Eds.), Forage Evaluation in Ruminant Nutrition, CAB International, UK, pp. 135-154. https://doi.org/10.1079/9780851993447.0135Padilha M.T.S., Licois D., Gidenne T., Carre B., Fonty G. 1995. Relationships between microflora and caecal fermentation in rabbits before and after weaning. Reprod. Nutr. Dev., 35: 375-386. https://doi.org/10.1051/rnd:19950403Pascual J.J., Cervera C., Fernández-Carmona J. 2000. Comparison of different in vitro digestibility methods for nutritive evaluation of rabbit diets. World Rabbit Sci., 8: 93-97. https://doi.org/10.4995/wrs.2000.425Penney R.L., Folk G.E., Galask R.P., Petzold C.R. 1986. The microflora of the alimentary tract of rabbits in relation to pH, diet and cold. J. Appl. Rabbit Res., 9: 152-156.Piattoni F., Demeyer D., Maertens L., 1997. Fasting effects on in vitro fermentation pattern of rabbit caecal contents. World Rabbit Sci., 5: 23-26. https://doi.org/10.4995/wrs.1997.314Rodríguez-Romero N., Abecia L., Fondevila M., Balcells J. 2011. Effects of levels of insoluble and soluble fibre in diets for growing rabbits on faecal digestibility, nitrogen recycling and in vitro fermentation. World Rabbit Sci., 19: 85-94. https://doi.org/10.4995/wrs.2011.828SAS Institute Inc. 2011. Base SAS® 9.3 Procedures Guide. SAS Institute Inc. Cary, NC, USA.Schofield P., Pitt R.E., Pell A.N. 1994. Kinetics of fiber digestion from in-vitro gas-production. J. Anim. Sci., 72: 2980-2991. https://doi.org/10.2527/1994.72112980xTagliapietra F., Williams B.A., Awati A., Bonsembiante M., Schiavon S., Verstegen M.W.A. 2003. In vitro degradation kinetics of four carbohydrates using ileal and faecal inocula from suckling piglets. Ital. J. Anim. Sci., 2: 195-197.Trocino A., García J., Carabaño R., Xiccato, G. 2013. A meta-analysis on the role of soluble fibre in diets for growing rabbits. World Rabbit Sci., 21: 1-15. https://doi.org/10.4995/wrs.2013.1285Van Soest P.J., Robertson J.B., Lewis B.A. 1991. Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. J. Dairy Sci., 74: 3583-3597. https://doi.org/10.3168/jds.S0022-0302(91)78551-2Wang D., Williams B.A., Ferruzzi M.G., D'Arcy B.R. 2013. Different concentrations of grape seed extract affect in vitro starch fermentation by porcine small and large intestinal inocula. J. Sci. 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Influence of essential oils (cinnamaldehyde and garlic oil) on rumen fermentation, feeding 1 behavior and performance of lactating dairy cattle

Two experiments were conducted to study the effects of Next Enhance® 300 (NE300; cinnamaldehyde and garlic oil encapsulated product) on rumen fermentation and milk production of dairy cows. In experiment 1, batch cultures of mixed rumen micro-organisms were used to study the effects of increasing concentrations of NE300 (0, 200, 300, and 400 mg/L) on ruminal fermentation in 24 h in vitro incubations. All tested doses decreased (P < 0.05) methane production, but the dose of 400 mg/L also reduced the production of volatile fatty acid (VFA). The addition of NE300 at 300 mg/L produced the most beneficial effects, reducing methane production, acetate proportion, and ammonia-N concentration, and increasing propionate proportion compared with CON, without affecting total VFA production. These results would indicate a potentially greater supply of energy for the host animal. In experiment 2, sixteen lactating dairy cows (8 rumen-cannulated) participated in a switch-back design with three 4-wk periods and 2 treatments: control (CON, unsupplemented) and NE300 (300 mg NE300/cow/d). Milk yield response was affected by a 3-way interaction among treatment, parity, and days on treatment; after 15 d on treatment, multiparous cows on NE300 produced more milk (approximately additional 3 kg/d) than multiparous cows on CON. Total rumen VFA concentrations tended (P = 0.06) to be greater in NE300 than in CON when rumen fermentation kinetics were evaluated at the end of each period (day 28). It is concluded that NE300 modifies ruminal fermentation resulting in increased milk yield in multiparous lactating dairy cows after 15 d of adaptation

In vitro ruminal fermentation and methane production of different seaweed species

Author's accepted version (post-print).Available from 29/03/2018.Seaweeds have potentials as alternative feed for ruminants, but there is a limited knowledge on their nutritive value. Seven seaweed species collected along the coast above the Arctic circle of Norway, both in spring and autumn, were assessed for nutrients and total polyphenols (TEP) content, gas production kinetics and in vitro rumen fermentation in batch cultures of ruminal microorganisms. The seaweeds were three red species (Mastocarpus stellatus, Palmaria palmata and Porphyra sp.), three brown species (Alaria esculenta, Laminaria digitata and Pelvetia canaliculata) and one green species (Acrosiphonia sp.). Additionally, the abundance and diversity of total bacteria, protozoa and archaea in the cultures with the three red seaweeds collected in spring were analyzed by quantitative PCR and PCR-DGGE, respectively. The crude protein (CP) content varied widely. Pelvetia had the greatest (P  0.05) among the other seaweeds in VFA production, but Porphyra sp. had the second highest methane production (P  0.05) by either seaweed species or the collection season. Higher final pH (P  0.05) in the abundance or the diversity of total bacteria, protozoa and archaea. In the PCR-DGGE analysis, samples were separated by the incubation run for all microbial populations analyzed, but not by seaweed species. The results indicate that seaweed species differ markedly in their in vitro rumen degradation, and that samples collected in autumn had lower rumen degradability than those collected in spring.acceptedVersio

Preserving Porphyra umbilicalis and Saccharina latissima as Silages for Ruminant Feeding

The study analyzed the characteristics, chemical composition, and in vitro gas production kinetics of Porphyra umbilicalis and Saccharina latissima silages. Each seaweed was ensiled in vacuum bags (three bags/silage) following a 2 × 3 factorial design, with two pre-treatments (unwilted or pre-wilted) and three silage types: unwashed seaweed ensiled without additive; seaweed washed and ensiled without additive; and seaweed washed and ensiled with 4 g of formic acid (FAC) per kg seaweed. Silages were kept for 3 months in darkness at 20 °C. Pre-wilting prevented (p < 0.001) effluent formation and reduced (p ≤ 0.038) the production of NH3-N and volatile fatty acids for both seaweeds. Both pre-wilting and washing increased (p < 0.05) the ruminal degradability of P. umbilicalis silages but not of S. latissima silages. The pH of the FAC-treated silages was below 4.0, but ranged from 4.54 to 6.23 in non FAC-treated silages. DL-lactate concentrations were low (≤23.0 g/kg dry matter) and acetate was the predominant fermentation product, indicating a non-lactic fermentation. The estimated ruminal degradability of the P. umbilicalis and S. latissima silages was as average, 59.9 and 86.1% of that for high-quality rye-grass silages, respectively, indicating a medium-low nutritional value of these seaweed silages for ruminants.publishedVersio

Efecto de la suplementación con celobiosa en el agua de bebida y del nivel e fibra soluble del pienso sobre los parámetros de crecimiento en conejos en cebo

El objetivo de este trabajo fue estudiar el efecto que tiene suplementar el agua con dosis de celobiosa inferiores a 7,5 g/l, en gazapos alimentados con dos niveles de fibra soluble sobre los parámetros productivos en gazapos en crecimiento. Se utilizaron 3 niveles de celobiosa en agua: 0, 3,5 y 7,0 g/l NPC Cello-Oligo combinados con 2 niveles de fibra soluble en el pienso (BF: 8,2 vs. AF: 10,5% sobre MS). Se utilizaron 240 gazapos destetados a los 26 d de edad (40/tratamiento), parte de los cuáles se sacrificaron a los 39 d de edad (8/tratamiento), momento en el que se sustituyeron los piensos experimentales por un pienso común estándar. La celobiosa se retiró a los 42 d de edad. En el periodo de 26 a 39 d de edad, los gazapos alimentados con el mayor nivel de fibra soluble redujeron un 6,4% el consumo de pienso respecto aquéllos alimentados con el nivel bajo de fibra soluble (P = 0,002), por lo que redujeron su ganancia de peso en un 7,0% (P = 0,002). En este periodo la ganancia de peso y la eficacia alimenticia de los animales alimentados con un bajo nivel de fibra soluble y 3,5 g celobiosa/l aumentaron en comparación con el promedio del grupo control y el de la dosis de 7 g/l (PBF(0+7 vs. 3,5) = 0,004 y 0,012, respectivamente), resultando en un peso mayor a los 39 d de edad (PBF(0+7 vs. 3,5) = 0,004). Los tratamientos no afectaron la actividad específica de la sacarasa en el yeyuno a los 39 d de edad. En el periodo global del cebo, el incremento de celobiosa redujo linealmente la ingestión (P = 0,040), tendiendo a mejorar la eficacia alimenticia (P = 0,10). Los gazapos que recibieron 3,5 g celobiosa/l en combinación con el pienso BF ganaron más peso que los que recibieron la dosis 0 ó 7 g celobiosa/l (PBF(0+7 vs 3,5) = 0,019). Por el contrario, los animales que recibieron la concentración intermedia de celobiosa en combinación con el pienso AF ganaron menos peso (PAF(0+7 vs 3,5) = 0,035). El nivel de fibra soluble no afectó a los rendimientos productivos ni a la mortalidad durante todo el periodo de cebo 26 a 56 d, pero el aumento de la concentración de celobiosa tendió a disminuir linealmente la mortalidad en los animales del grupo BF (PBF(0 vs 3,5 vs 7) = 0,069), mientras que los del grupo AF y que recibieron la concentración intermedia de celobiosa la mortalidad tendió a ser más baja (PAF(0+7 vs 3,5) = 0,11)

How to Assess Diabetic Kidney Disease Progression? From Albuminuria to GFR

Malaltia renal crònica; Diabetis mellitus; Malaltia renal diabèticaEnfermedad renal crónica; Diabetes mellitus; Enfermedad renal diabéticaChronic kidney disease; Diabetes mellitus; Diabetic kidney diseaseDiabetic kidney disease (DKD) is one of the most relevant complications of type 2 diabetes and dramatically increases the cardiovascular risk in these patients. Currently, DKD is severely infra-diagnosed, or its diagnosis is usually made at advanced stages of the disease. During the last decade, new drugs have demonstrated a beneficial effect in terms of cardiovascular and renal protection in type 2 diabetes, supporting the crucial role of an early DKD diagnosis to permit the use of new available therapeutic strategies. Moreover, cardiovascular and renal outcome trials, developed to study these new drugs, are based on diverse cardiovascular and renal simple and composite endpoints, which makes difficult their interpretation and the comparison between them. In this article, DKD diagnosis is reviewed, focusing on albuminuria and the recommendations for glomerular filtration rate measurement. Furthermore, cardiovascular and renal endpoints used in classical and recent cardiovascular outcome trials are assessed in a pragmatic way.The authors are current recipients of research grants from the Fondo de Investigación Sanitaria-Feder—Instituto de Salud Carlos III (PI17/00257) and REDinREN (RD16/0009/0030)

Efecto del nivel de fibra soluble y de la suplementación con celobiosa sobre los rendimientos productivos en conejos en cebo

El objetivo de este trabajo fue estudiar el efecto de la fibra soluble y la suplementación de con celobiosa en agua sobre los rencimientos productivos del gazapo tras el destete. A los gazapos se les suministró dos piensos que difirieron en el nivel de fibra soluble (7,7 vs.15,2%, sobre MS) y tres concentraciones de celobiosa en agua (0,0,75 y 1,5 fl). Los piensos y la celobiosa se suministraron a gazapos desde el destete (34 d edad 781±88 g, 44 gazapos/pienso) hasta los 48 d edad

New aspects and strategies for methane mitigation from ruminants

The growing demand for sustainable animal production is compelling researchers to explore the potential approaches to reduce emissions of greenhouse gases from livestock that are mainly produced by enteric fermentation. Some potential solutions, for instance, the use of chemical inhibitors to reduce methanogenesis, are not feasible in routine use due to their toxicity to ruminants, inhibition of efficient rumen function or other transitory effects. Strategies, such as use of plant secondary metabolites and dietary manipulations have emerged to reduce the methane emission, but these still require extensive research before these can be recommended and deployed in the livestock industry sector. Furthermore, immunization vaccines for methanogens and phages are also under investigation for mitigation of enteric methanogenesis. The increasing knowledge of methanogenic diversity in rumen, DNA sequencing technologies and bioinformatics have paved the way for chemogenomic strategies by targeting methane producers. Chemogenomics will help in finding target enzymes and proteins, which will further assist in the screening of natural as well chemical inhibitors. The construction of a methanogenic gene catalogue through these approaches is an attainable objective. This will lead to understand the microbiome function, its relation with the host and feeds, and therefore, will form the basis of practically viable and eco-friendly methane mitigation approaches, while improving the ruminant productivity