Animal Production Science Animal Production Science Society
Food, fibre and pharmaceuticals from animals
RESEARCH ARTICLE

Effect of dietary crude protein and forage contents on enteric methane emissions and nitrogen excretion from dairy cows simultaneously

M. Niu A C , J. A. D. R. N. Appuhamy A , A. B. Leytem B , R. S. Dungan B and E. Kebreab A
+ Author Affiliations
- Author Affiliations

A Department of Animal Science, University of California, Davis, CA 95616, USA.

B USDA-ARS, Northwest Irrigation and Soils Research Laboratory, Kimberly, ID 83341, USA.

C Corresponding author. Email: mniu@ucdavis.edu

Animal Production Science 56(3) 312-321 https://doi.org/10.1071/AN15498
Submitted: 28 August 2015  Accepted: 20 November 2015   Published: 9 February 2016

Abstract

The study aimed to examine, simultaneously, the effects of changing dietary forage and crude protein (CP) contents on enteric methane (CH4) emissions and nitrogen (N) excretion from lactating dairy cows. Twelve post-peak lactating Holstein cows (157 ± 31 days postpartum; mean ± s.d.) were randomly assigned to four treatments from a 2 × 2 factorial arrangement of two dietary forage levels [37.4% (LF) vs 53.3% (HF) of DM] and two dietary CP levels [15.2% (LP) vs 18.5% (HP) of DM] in a 4 × 4 Latin square design with four 18-day periods. Alfalfa hay was the sole source of dietary forage. Cows were fed ad libitum and milked twice daily. During the first 14 days, cows were housed in a free-stall barn, where enteric CH4 emissions were measured using the GreenFeed system from Days 8 to 14 in each period. Cows were then moved to metabolic cages, where faeces and urine output (kg/cow.day) were measured by total collection from Days 16 to 18 of each period. No dietary forage by CP interactions were detected for DM intake, milk production, enteric CH4 emissions, or N excretions. There was a tendency for DM intake to increase 0.6 kg/day in cows fed LF (P = 0.06). Milk production increased 2.1 kg/day in LF compared with HF (P < 0.01). Milk fat content decreased in cows fed LF compared with HF (1.07 vs 1.17 kg/day; P < 0.01). Milk contents of true protein, lactose and solid non-fat were greater in cows fed LF (P < 0.01). No difference in DM intake, milk yield and milk contents of true protein, lactose and solid non-fat was found between cows fed HP or LP. However, milk fat content increased 0.16 kg/day in cows fed HP (P < 0.05). Enteric CH4 emissions, and CH4 per unit of DM intake, energy-corrected milk, total digested organic matter and neutral detergent fibre were not affected by dietary CP, but decreased by LF compared with HF (P < 0.01). Milk true protein N was not affected by dietary CP content but was higher for LF compared with HF. Dietary N partitioned to milk true protein was greater in cows fed LF compared with HF (29.4% vs 26.7%; P < 0.01), also greater in cows fed LP compared with HP (30.8% vs 25.2%; P < 0.01). Dietary N partitioned to urinary N excretion was greater in cows fed HP compared with LP (39.5% vs 29.6%; P < 0.01) but was not affected by dietary CP content. Dietary N partitioned to faeces was not affected by dietary CP but increased in cows fed LP compared with HP (34.2% vs 27.8%; P < 0.01). Total N excretion (urinary plus faecal) as proportion to N intake did not differ between HP and LP, but tended to be lower in cows fed LF compared with the HF diet (64.2% vs 67.9%; P = 0.09). Both milk urea N (P < 0.01) and blood urea N (P < 0.01) declined with decreasing dietary CP or forage contents. Based on purine derivative analysis, there was a tendency for interaction between dietary CP and forage content on microbial protein synthesis (P < 0.09). Rumen microbial protein synthesis tended to be lower for high forage and low protein treatments. Increasing dietary forage contents resulted in greater CH4 emission (g/kg of energy-corrected milk) and manure N excretion (g/kg of energy-corrected milk) intensities of lactating dairy cows. Cows receiving reduced CP diets had low manure N outputs and improved milk true protein production efficiencies, regardless of dietary forage content.

Additional keyword: lactating dairy cow.


References

Abecia L, Toral PG, Martín-García AI, Martínez G, Tomkins NW, Molina-Alcaide E, Newbold CJ, Yáñez-Ruiz DR (2012) Effect of bromochloromethane on methane emission, rumen fermentation pattern, milk yield, and fatty acid profile in lactating dairy goats. Journal of Dairy Science 95, 2027–2036.
Effect of bromochloromethane on methane emission, rumen fermentation pattern, milk yield, and fatty acid profile in lactating dairy goats.CrossRef | 1:CAS:528:DC%2BC38Xksleitrw%3D&md5=766d1043207ecfa67a2187113a1ecd62CAS | 22459848PubMed |

Acharya IP, Schingoethe DJ, Kalscheur KF, Casper DP (2015) Response of lactating dairy cows to dietary protein from canola meal or distillers’ grains on dry matter intake, milk production, milk composition, and amino acid status. Canadian Journal of Animal Science 95, 267–279.
Response of lactating dairy cows to dietary protein from canola meal or distillers’ grains on dry matter intake, milk production, milk composition, and amino acid status.CrossRef | 1:CAS:528:DC%2BC2MXhsFejur7M&md5=634185641fef8af17a1b06e3c62ba875CAS |

Aguerre MJ, Wattiaux MA, Powell JM, Broderick GA, Arndt C (2011) Effect of forage-to-concentrate ratio in dairy cow diets on emission of methane, carbon dioxide, and ammonia, lactation performance, and manure excretion. Journal of Dairy Science 94, 3081–3093.
Effect of forage-to-concentrate ratio in dairy cow diets on emission of methane, carbon dioxide, and ammonia, lactation performance, and manure excretion.CrossRef | 1:CAS:528:DC%2BC3MXnvFCnsr4%3D&md5=5c52ee4e1d029e4ef729ac62d308c416CAS | 21605777PubMed |

Allen MS (2000) Effects of diet on short-term regulation of feed intake by lactating dairy cattle. Journal of Dairy Science 83, 1598–1624.
Effects of diet on short-term regulation of feed intake by lactating dairy cattle.CrossRef | 1:CAS:528:DC%2BD3cXltVGgtb0%3D&md5=c69ce5021ab1a23d1d96046e65fbf750CAS | 10908065PubMed |

AOAC (2000) ‘Official methods of analysis.’ 17th edn. (Association of Official Analytical Chemists: Arlington, VA)

Appuhamy JADRN, Wagner-Riddle C, Casper DP, France J, Kebreab E (2014) Quantifying body water kinetics and fecal and urinary water output from lactating Holstein dairy cows. Journal of Dairy Science 97, 6177–6195.
Quantifying body water kinetics and fecal and urinary water output from lactating Holstein dairy cows.CrossRef | 1:CAS:528:DC%2BC2cXhtlSqurjM&md5=3faeb60a51d340676c25098ae070d5e1CAS |

Bach A, Calsamiglia S, Stern MD (2005) Nitrogen metabolism in the rumen. Journal of Dairy Science 88, E9–E21.
Nitrogen metabolism in the rumen.CrossRef | 15876575PubMed |

Bannink A, France J, Lopez S, Gerrits WJJ, Kebreab E, Tamminga S, Dijkstra J (2008) Modelling the implications of feeding strategy on rumen fermentation and functioning of the rumen wall. Animal Feed Science and Technology 143, 3–26.
Modelling the implications of feeding strategy on rumen fermentation and functioning of the rumen wall.CrossRef |

Bannink A, Smits MCJ, Kebreab E, Mills JAN, Ellis JL, Klop A, France J, Dijkstra J (2010) Simulating the effects of grassland management and grass ensiling on methane emission from lactating cows. The Journal of Agricultural Science 148, 55–72.
Simulating the effects of grassland management and grass ensiling on methane emission from lactating cows.CrossRef | 1:CAS:528:DC%2BD1MXhs1Skt77K&md5=cddbe8f793ce73e49c50661a607941a7CAS |

Bauman DE, Griinari JM (2001) Regulation and nutritional manipulation of milk fat: low-fat milk syndrome. Livestock Production Science 70, 15–29.
Regulation and nutritional manipulation of milk fat: low-fat milk syndrome.CrossRef |

Beauchemin KA, Kreuzer M, O’Mara F, McAllister TA (2008) Nutritional management for enteric methane abatement: a review. Australian Journal of Experimental Agriculture 48, 21–27.
Nutritional management for enteric methane abatement: a review.CrossRef | 1:CAS:528:DC%2BD1cXovVGn&md5=23b38df440406cdf954ea8c1fc39bac0CAS |

Beauchemin KA, McGinn SM, Benchaar C, Holtshausen L (2009) Crushed sunflower, flax, or canola seeds in lactating dairy cow diets: effects on methane production, rumen fermentation, and milk production. Journal of Dairy Science 92, 2118–2127.
Crushed sunflower, flax, or canola seeds in lactating dairy cow diets: effects on methane production, rumen fermentation, and milk production.CrossRef | 1:CAS:528:DC%2BD1MXlsFyms74%3D&md5=aca2b5be85877a8fd1801eb741204c4fCAS | 19389969PubMed |

Branco AF, Giallongo F, Frederick T, Weeks H, Oh J, Hristov AN (2015) Effect of technical cashew nut shell liquid on rumen methane emission and lactation performance of dairy cows. Journal of Dairy Science 98, 4030–4040.
Effect of technical cashew nut shell liquid on rumen methane emission and lactation performance of dairy cows.CrossRef | 1:CAS:528:DC%2BC2MXks1ejs7c%3D&md5=cc64142656c0a66e8231734104ac29faCAS | 25795493PubMed |

Broderick GA (2003) Effects of varying dietary protein and energy levels on the production of lactating dairy cows. Journal of Dairy Science 86, 1370–1381.
Effects of varying dietary protein and energy levels on the production of lactating dairy cows.CrossRef | 1:CAS:528:DC%2BD3sXjtVajtLc%3D&md5=b78fbd12472abc269ed0a8d1d19b8022CAS | 12741562PubMed |

Bunting LD, Boling JA, MacKown CT, Muntifering RB (1987) Effect of dietary protein level on nitrogen metabolism in lambs: studies using N-nitrogen. Journal of Animal Science 64, 855–867.

Calsamiglia S, Ferret A, Reynolds CK, Kristensen NB, van Vuuren AM (2010) Strategies for optimizing nitrogen use by ruminants. Animal 4, 1184–1196.
Strategies for optimizing nitrogen use by ruminants.CrossRef | 1:CAS:528:DC%2BC3cXmvVajsbs%3D&md5=786f1e28d48b934fa9ed7a4ffdf1b0e4CAS | 22444616PubMed |

Castillo AR, Kebreab E, Beever DE, Barbi JH, Sutton JD, Kirby HC, France J (2001) The effect of protein supplementation on nitrogen utilization in lactating dairy cows fed grass silage diets. Journal of Animal Science 79, 247–253.

Chen XB, Chen YK, Franklin MF, Orskov ER, Shand WJ (1992) The effect of feed intake and body weight on purine derivative excretion and microbial protein supply in sheep. Journal of Animal Science 70, 1534–1542.

Colmenero JJO, Broderick GA (2006) Effect of dietary crude protein concentration on milk production and nitrogen utilization in lactating dairy cows. Journal of Dairy Science 89, 1704–1712.
Effect of dietary crude protein concentration on milk production and nitrogen utilization in lactating dairy cows.CrossRef | 1:CAS:528:DC%2BD28XktVOhtrs%3D&md5=46ae93c0c5b146e01ee8c0163925afbaCAS |

Cottle DJ, Velazco J, Hegarty RS, Mayer DG (2015) Estimating daily methane production in individual cattle with irregular feed intake patterns from short-term methane emission measurements. Animal 1–9.

Dijkstra J, Oenema O, Bannink A (2011a) Dietary strategies to reducing N excretion from cattle: implications for methane emissions. Current Opinion in Environmental Sustainability 3, 414–422.
Dietary strategies to reducing N excretion from cattle: implications for methane emissions.CrossRef |

Dijkstra J, France J, Ellis JL, Kebreab E, López S, Reijs JW, Bannink A (2011b) Effects of nutritional strategies on simulated nitrogen excretion and methane emission in dairy cattle. In ‘Modelling nutrient digestion and utilisation in farm animals’. (Eds D Sauvant, J Van Milgen, P Faverdin, N Friggens) pp. 394–402. (Wageningen Academic Publishers: Wageningen)

FAO (2009) ‘The State of Food and Agriculture 2009. Livestock in the balance.’ (Food and Agriculture Organization of the United Nations: Rome)

Firkins JL, Reynolds C (2005) Whole-animal nitrogen balance in cattle. In ‘Nitrogen and phosphorus nutrition of cattle: reducing the environmental impact of cattle operations’. (Eds E Pfeffer, A Hristov) pp. 167–186. (The Centre for Agriculture and Bioscience International Publishing: Cambridge, MA)

Forster P, Ramaswamy V, Artaxo P, Berntsen T, Betts R, Fahey DW, Haywood J, Lean J, Lowe DC, Myhre G, Nganga J, Prinn R, Raga G, Schulz M, Van Dorland R (2007) Changes in atmospheric constituents and in radiative forcing. In ‘Climate Change 2007: the physical science basis. Contribution of Working Group I to the Fourth Assessment Report of the Intergovernmental Panel on Climate Change’. (Eds S Solomon, D Qin, M Manning, Z Chen, M Marquis, KB Averyt, M Tignor, HL Miller) (Cambridge University Press: Cambridge, UK and New York, NY)

Goering HK, Van Soest PJ (1970) Forage analyses. Africulture Handbook 379. Agricultural Research Service United States Department of Agriculture.

Hall MB (2008) Determination of starch, including maltooligosaccharides, in animal feeds: comparison of methods and a method recommended for AOAC collaborative study. Journal of AOAC International 92, 42–49.

Hristov AN, Etter RP, Ropp JK, Grandeen KL (2004) Effect of dietary crude protein level and degradability on ruminal fermentation and nitrogen utilization in lactating dairy cows. Journal of Animal Science 82, 3219–3229.

Hristov AN, Vander Pol M, Agle M, Zaman S, Schneider C, Ndegwa P, Vaddella VK, Johnson K, Shingfield KJ, Karnati SKR (2009) Effect of lauric acid and coconut oil on ruminal fermentation, digestion, ammonia losses from manure, and milk fatty acid composition in lactating cows. Journal of Dairy Science 92, 5561–5582.
Effect of lauric acid and coconut oil on ruminal fermentation, digestion, ammonia losses from manure, and milk fatty acid composition in lactating cows.CrossRef | 1:CAS:528:DC%2BD1MXhtlKnsrfL&md5=9584f03d84d68d0040691d5982cad169CAS | 19841218PubMed |

Hristov AN, Oh J, Lee C, Meinen R, Montes F, Ott T, Firkins J, Rotz A, Dell C, Adesogan A, Yang W, Tricarico J, Kebreab E, Waghorn G, Dijkstra J, Oosting S (2013) ‘Mitigation of greenhouse gas emissions in livestock production – A review of technical options for non-CO2 emissions.’ (Eds Pierre J. Gerber, Benjamin Henderson, Harinder P. S. Makkar) FAO Animal Production and Health Paper No. 177. (Food and Agriculture Organization of the United Nations: Rome, Italy)

Ipharraguerre IR, Clark JH (2005) Impacts of the source and amount of crude protein on the intestinal supply of nitrogen fractions and performance of dairy cows. Journal of Dairy Science 88, E22–E37.
Impacts of the source and amount of crude protein on the intestinal supply of nitrogen fractions and performance of dairy cows.CrossRef | 15876574PubMed |

Johnson KA, Johnson DE (1995) Methane emissions from cattle. Journal of Animal Science 73, 2483–2492.

Kebreab E, France J, Mills JAN, Allison R, Dijkstra J (2002) A dynamic model of N metabolism in the lactating dairy cow and an assessment of impact of N excretion on the environment. Journal of Animal Science 80, 248–259.

Kebreab E, Clark K, Wagner-Riddle C, France J (2006) Methane and nitrous oxide emissions from Canadian animal agriculture: A review. Canadian Journal of Animal Science 86, 135–157.
Methane and nitrous oxide emissions from Canadian animal agriculture: A review.CrossRef | 1:CAS:528:DC%2BD28Xht1aktb7E&md5=b7e3ec0debb3f39b1eb0e94f281a9734CAS |

Knowlton KF, McGilliard ML, Zhao Z, Hall KG, Mims W, Hanigan MD (2010) Effective nitrogen preservation during urine collection from Holstein heifers fed diets with high or low protein content. Journal of Dairy Science 93, 323–329.
Effective nitrogen preservation during urine collection from Holstein heifers fed diets with high or low protein content.CrossRef | 1:CAS:528:DC%2BD1MXhs1WhtbrN&md5=25fc0eb63a93767a2e4eca3bde1cd899CAS | 20059930PubMed |

Koenig KM, Beauchemin KA (2013) Nitrogen metabolism and route of excretion in beef feedlot cattle fed barley-based finishing diets varying in protein concentration and rumen degradability. Journal of Animal Science 91, 2310–2320.
Nitrogen metabolism and route of excretion in beef feedlot cattle fed barley-based finishing diets varying in protein concentration and rumen degradability.CrossRef | 1:CAS:528:DC%2BC3sXotl2gtbk%3D&md5=b0b9d25d20c72e2b6e26ac26466942f6CAS | 23478813PubMed |

Leonardi C, Stevenson M, Armentano LE (2003) Effect of two levels of crude protein and methionine supplementation on performance of dairy cows. Journal of Dairy Science 86, 4033–4042.
Effect of two levels of crude protein and methionine supplementation on performance of dairy cows.CrossRef | 1:CAS:528:DC%2BD3sXhtVWgs7fK&md5=8f00bd365c0d848cad2b1437cf6ad3ebCAS | 14740841PubMed |

Lovett D, Lovell S, Stack L, Callan J, Finlay M, Conolly J, O’Mara FP (2003) Effect of forage/concentrate ratio and dietary coconut oil level on methane output and performance of finishing beef heifers. Livestock Production Science 84, 135–146.
Effect of forage/concentrate ratio and dietary coconut oil level on methane output and performance of finishing beef heifers.CrossRef |

Maxin G, Glasser F, Hurtaud C, Peyraud JL, Rulquin H (2011) Combined effects of trans-10,cis-12 conjugated linoleic acid, propionate, and acetate on milk fat yield and composition in dairy cows. Journal of Dairy Science 94, 2051–2059.
Combined effects of trans-10,cis-12 conjugated linoleic acid, propionate, and acetate on milk fat yield and composition in dairy cows.CrossRef | 1:CAS:528:DC%2BC3MXnvFChurk%3D&md5=416b04698130b151b058489487bdeb0cCAS | 21426996PubMed |

Menzi H, Oenema O, Burton C, Shipin O, Gerber P, Robinson T, Franceschini G (2010) Impacts of intensive livestock production and manure management on the environment. In ‘Livestock in a changing landscape, Volume 1: drivers, consequences and responses’. (Eds H Steinfeld, H Mooney, F Schneider, L Neville) pp. 139–163. (Island Press: Washington, DC)

Moate PJ, Williams SRO, Grainger C, Hannah MC, Ponnampalam EN, Eckard RJ (2011) Influence of cold-pressed canola, brewers grains and hominy meal as dietary supplements suitable for reducing enteric methane emissions from lactating dairy cows. Animal Feed Science and Technology 166–167, 254–264.
Influence of cold-pressed canola, brewers grains and hominy meal as dietary supplements suitable for reducing enteric methane emissions from lactating dairy cows.CrossRef |

Morgavi DP, Forano E, Martin C, Newbold CJ (2010) Microbial ecosystem and methanogenesis in ruminants. Animal 4, 1024–1036.
Microbial ecosystem and methanogenesis in ruminants.CrossRef | 1:CAS:528:DC%2BC3cXmvVajtr0%3D&md5=b95aa96aedc98e44e77cbe2f14f00d3fCAS | 22444607PubMed |

Neveu C, Baurhoo B, Mustafa A (2013) Effect of feeding extruded flaxseed with different forage:concentrate ratios on the performance of dairy cows. Journal of Dairy Science 96, 3886–3894.
Effect of feeding extruded flaxseed with different forage:concentrate ratios on the performance of dairy cows.CrossRef | 1:CAS:528:DC%2BC3sXmt12isrg%3D&md5=56d0642d4a30f25d2dec8ebce90b82ecCAS | 23608490PubMed |

Niu M, Ying Y, Bartell PA, Harvatine KJ (2014) The effects of feeding time on milk production, total-tract digestibility, and daily rhythms of feeding behavior and plasma metabolites and hormones in dairy cows. Journal of Dairy Science 97, 7764–7776.
The effects of feeding time on milk production, total-tract digestibility, and daily rhythms of feeding behavior and plasma metabolites and hormones in dairy cows.CrossRef | 1:CAS:528:DC%2BC2cXhslehur7E&md5=e36c600fba35ef1b4441f2cdd15fd118CAS | 25306274PubMed |

NRC (2001) ‘Nutrient requirements of dairy cattle.’ 7th rev. edn. (National Academy of Sciences: Washington, DC)

Piao H, Lachman M, Malfatti S, Sczyrba A, Knierim B, Auer M, Tringe SG, Mackie RI, Yeoman CJ, Hess M (2014) Temporal dynamics of fibrolytic and methanogenic rumen microorganisms during in situ incubation of switchgrass determined by 16S rRNA gene profiling. Frontiers in Microbiology 5, 307
Temporal dynamics of fibrolytic and methanogenic rumen microorganisms during in situ incubation of switchgrass determined by 16S rRNA gene profiling.CrossRef | 25101058PubMed |

Reijs JW, Sonneveld MPW, Sørensen P, Schils RLM, Groot JCJ, Lantinga EA (2007) Effects of different diets on utilization of nitrogen from cattle slurry applied to grassland on a sandy soil in The Netherlands. Agriculture, Ecosystems & Environment 118, 65–79.
Effects of different diets on utilization of nitrogen from cattle slurry applied to grassland on a sandy soil in The Netherlands.CrossRef | 1:CAS:528:DC%2BD28Xht1CnsLvN&md5=86748a273562934559c75f22399e21f4CAS |

Richardson D, Felgate H, Watmough N, Thomson A, Baggs E (2009) Mitigating release of the potent greenhouse gas N2O from the nitrogen cycle – could enzymic regulation hold the key? Trends in Biotechnology 27, 388–397.
Mitigating release of the potent greenhouse gas N2O from the nitrogen cycle – could enzymic regulation hold the key?CrossRef | 1:CAS:528:DC%2BD1MXnslymsbs%3D&md5=02bb30fa5dd51f7f8fd1d45690165b8eCAS | 19497629PubMed |

Sauvant D, Eugène M, Giger-Reverdin S, Archimède H, Doreau M (2014) Relationship between CH4 and urinary N outputs in ruminants fed forages: a meta-analysis of the literature. Animal Production Science 54, 1423–1427.
Relationship between CH4 and urinary N outputs in ruminants fed forages: a meta-analysis of the literature.CrossRef | 1:CAS:528:DC%2BC2cXhtlaktLjJ&md5=c7afb5172c08ef29c13df639a857c94bCAS |

Silva-del-Rio N, Heguy JM, Lago A (2010) Feed management practices on California dairies. Journal of Dairy Science 93, 773

Sjaunja LO, Baevre L, Junkkarinen L, Pedersen J, Setala J (1990) A Nordic proposal for an energy corrected milk (ECM) formula. In ‘European Association for Animal Production Publication, performance recording of animals: State of the Art, 1990; 27th biennial session of the International Committee for Animal Recording’. (Eds P Gaillon, Y Chabert) pp. 156–192. (Centre for Agricultural Publishing and Documentation: Paris, France)

Steinfeld H, Gerber P, Wassenaar T, Castel V, Rosales M, Haan Cd (2006) ‘Livestock’s long shadow: environmental issues and options.’ (Food and Agriculture Organization of the United Nations: Rome)

Stern MD, Hoover WH (1979) Methods for determining and factors affecting rumen microbial protein synthesis: a review. Journal of Animal Science 49, 1590–1603.

Swanepoel N, Robinson PH, Erasmus LJ (2010) Amino acid needs of lactating dairy cows: predicting limiting amino acids in contemporary rations fed to high producing dairy cattle in California using metabolic models. Animal Feed Science and Technology 161, 103–120.
Amino acid needs of lactating dairy cows: predicting limiting amino acids in contemporary rations fed to high producing dairy cattle in California using metabolic models.CrossRef | 1:CAS:528:DC%2BC3cXhtlOhsr3M&md5=ac10046e598b099a4da2f99bd4d3744bCAS |

Valadares RFD, Broderick GA, Filho SCV, Clayton MK (1999) Effect of replacing alfalfa silage with high moisture corn on ruminal protein synthesis estimated from excretion of total purine derivatives1. Journal of Dairy Science 82, 2686–2696.
Effect of replacing alfalfa silage with high moisture corn on ruminal protein synthesis estimated from excretion of total purine derivatives1.CrossRef | 1:CAS:528:DC%2BD3cXis1Or&md5=802bde2f587c10386dcca000cbd6af25CAS |

van Kessel JAS, Russell JB (1996) The effect of pH on ruminal methanogenesis. FEMS Microbiology Ecology 20, 205–210.
The effect of pH on ruminal methanogenesis.CrossRef | 1:CAS:528:DyaK28XkslGiur4%3D&md5=98d6165300bb1728873629b1d1b6bfb8CAS |

Van Soest PJ, Robertson JB, Lewis BA (1991) Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition. Journal of Dairy Science 74, 3583–3597.
Methods for dietary fiber, neutral detergent fiber, and nonstarch polysaccharides in relation to animal nutrition.CrossRef | 1:STN:280:DyaK38%2FnvVCltA%3D%3D&md5=5ac74045d70ec4fdb1b477d24fb39c1dCAS | 1660498PubMed |

Voelker JA, Burato GM, Allen MS (2002) Effects of pretrial milk yield on responses of feed intake, digestion, and production to dietary forage concentration. Journal of Dairy Science 85, 2650–2661.
Effects of pretrial milk yield on responses of feed intake, digestion, and production to dietary forage concentration.CrossRef | 1:CAS:528:DC%2BD38XotlCms70%3D&md5=77e45501a1ead593c71151c76c98c0abCAS | 12416819PubMed |

Waghorn GC, Tavendale MH, Woodfield DR (2002) Methanogenesis from forages fed to sheep. Proceedings of the New Zealand Grasslands 64, 167–171.

Williams YJ, Popovski S, Rea SM, Skillman LC, Toovey AF, Northwood KS, Wright A-DG (2009) A vaccine against rumen methanogens can alter the composition of archaeal populations. Applied and Environmental Microbiology 75, 1860–1866.
A vaccine against rumen methanogens can alter the composition of archaeal populations.CrossRef | 1:CAS:528:DC%2BD1MXksFWlsb0%3D&md5=c9bbbba891176c412cb56884f62c575fCAS | 19201957PubMed |

Zimmerman P, Zimmerman S, Utsumi S, Beede D (2011) Development of a user-friendly online system to quantitatively measure metabolic gas fluxes from ruminants. Journal of Dairy Science 94, 760



Rent Article (via Deepdyve) Export Citation Cited By (4)