Methane emissions by Charolais cows grazing a monospecific pasture of timothy at four stages of maturity

Grass silage is typically fed to dairy cows in temperate regions. However, in vivo information on methane (CH 4 ) emission from grass silage of varying quality is limited. We evaluated the effect of two rates of nitrogen (N) fertilisation of grassland (low fertilisation (LF), 65 kg of N/ha; and high fertilisation (HF), 150 kg of N/ha) and of three stages of maturity of grass at cutting: early maturity (EM; 28 days of regrowth), mid maturity (MM; 41 days of regrowth) and late maturity (LM; 62 days of regrowth) on CH 4 production by lactating dairy cows. In a randomised block design, 54 lactating Holstein-Friesian dairy cows (168 ± 11 days in milk; mean ± standard error of mean) received grass silage (mainly ryegrass) and compound feed at 80 : 20 on dry matter basis. Cows were adapted to the diet for 12 days and CH 4 production was measured in climate respiration chambers for 5 days. Dry matter intake (DMI; 14.9 ± 0.56 kg/day) decreased with increasing N fertilisation and grass maturity. Production of fat-and proteincorrected milk (FPCM; 24.0 ± 1.57 kg/day) decreased with advancing grass maturity but was not affected by N fertilisation. Apparent total-tract feed digestibility decreased with advancing grass maturity but was unaffected by N fertilisation except for an increase and decrease in N and fat digestibility with increasing N fertilisation, respectively. Total CH 4 production per cow (347 ± 13.6 g/day) decreased with increasing N fertilisation by 4% and grass maturity by 6%. The smaller CH 4 production with advancing grass maturity was offset by a smaller FPCM and lower feed digestibility. As a result, with advancing grass maturity CH 4 emission intensity increased per units of FPCM (15.0 ± 1.00 g CH 4 /kg) by 31% and digestible organic matter intake (33.1 ± 0.78 g CH 4 /kg) by 15%. In addition, emission intensity increased per units of DMI (23.5 ± 0.43 g CH 4 /kg) by 7% and gross energy intake (7.0 ± 0.14% CH 4 ) by 9%, implying an increased loss of dietary energy with advancing grass maturity. Rate of N fertilisation had no effect on CH 4 emissions per units of FPCM, DMI and gross energy intake. These results suggest that despite a lower absolute daily CH 4 production with a higher N fertilisation rate, CH 4 emission intensity remains unchanged. A significant reduction of CH 4 emission intensity can be achieved by feeding dairy cows silage of grass harvested at an earlier stage of maturity.

“…Similar relationships were reported in other studies (e.g. Pinares-Patiño et al, 2003;Hart et al, 2009). …”

Section: Discussionsupporting

confidence: 92%

Section: Discussionsupporting

confidence: 91%

Section: Discussionsupporting

confidence: 91%

See 1 more Smart Citation

Effects of nitrogen fertilisation rate and maturity of grass silage on methane emission by lactating dairy cows

Warner

Hatew

Podesta

et al. 2016

“…Robertson and Waghorn (2002) observed that CH 4 production from grazing dairy cows increased with forage maturity (from 5% to 6.5% of GE intake in spring and summer, respectively). This was not observed in other experiments, for example, for cows grazing a monospecific pasture of timothy at four stages of maturity over the grazing season (Pinares-Patiñ o et al, 2003a). A putative decrease in CH 4 with young fresh forages may be explained by a higher content of soluble sugars and linolenic acid (see subsequently).…”

Section: Mitigation Through Feedingmentioning

confidence: 65%

Methane mitigation in ruminants: from microbe to the farm scale

Martin

Morgavi

Doreau

2010

Self Cite

747

657

Decreasing enteric methane (CH 4 ) emissions from ruminants without altering animal production is desirable both as a strategy to reduce global greenhouse gas (GHG) emissions and as a means of improving feed conversion efficiency. The aim of this paper is to provide an update on a selection of proved and potential strategies to mitigate enteric CH 4 production by ruminants. Various biotechnologies are currently being explored with mixed results. Approaches to control methanogens through vaccination or the use of bacteriocins highlight the difficulty to modulate the rumen microbial ecosystem durably. The use of probiotics, i.e. acetogens and live yeasts, remains a potentially interesting approach, but results have been either unsatisfactory, not conclusive, or have yet to be confirmed in vivo. Elimination of the rumen protozoa to mitigate methanogenesis is promising, but this option should be carefully evaluated in terms of livestock performances. In addition, on-farm defaunation techniques are not available up to now. Several feed additives such as ionophores, organic acids and plant extracts have also been assayed. The potential use of plant extracts to reduce CH 4 is receiving a renewed interest as they are seen as a natural alternative to chemical additives and are well perceived by consumers. The response to tannin-and saponincontaining plant extracts is highly variable and more research is needed to assess the effectiveness and eventual presence of undesirable residues in animal products. Nutritional strategies to mitigate CH 4 emissions from ruminants are, without doubt, the most developed and ready to be applied in the field. Approaches presented in this paper involve interventions on the nature and amount of energy-based concentrates and forages, which constitute the main component of diets as well as the use of lipid supplements. The possible selection of animals based on low CH 4 production and more likely on their high efficiency of digestive processes is also addressed. Whatever the approach proposed, however, before practical solutions are applied in the field, the sustainability of CH 4 suppressing strategies is an important issue that has to be considered. The evaluation of different strategies, in terms of total GHG emissions for a given production system, is discussed.Keywords: methane, greenhouse gases, ruminant, mitigation strategies Implications Methane (CH 4 ) mitigation in ruminants is possible through various strategies. Today, the feeding management approach is the most developed. Other strategies (biotechnologies, additives) are promising but the diversity and plasticity of functions of the rumen bacterial and methanogenic communities may be a limiting factor for their successful application. A possible selection of animals on CH 4 production and more likely on digestive processes is evocated. In any case, before practical solutions are proposed for field application more research in vivo is needed. The sustainability of CH 4 -suppressing strategies is also an important issue and they mi...

“…Methane production could be directly recorded by analyzing the gas produced by the cow. At least two approaches have been used: in the first one, the gas produced is collected in a bottle and methane is measured by comparison with a reference gas (SF6) delivered at a constant rate by a bolus put in the rumen (Pinares-Patiñ o et al, 2003); in the second approach, the cow is placed in a respiratory chamber. The principle of the respiratory chamber was recently adapted to the milking robot.…”

Section: Introductionmentioning

confidence: 99%

New phenotypes for new breeding goals in dairy cattle

Boichard

Brochard

2012

109

Cattle production faces new challenges regarding sustainability with its three pillars -economic, societal and environmental. The following three main factors will drive dairy cattle selection in the future: (1) During a long period, intensive selection for enhanced productivity has deteriorated most functional traits, some reaching a critical point and needing to be restored. This is especially the case for the Holstein breed and for female fertility, mastitis resistance, longevity and metabolic diseases.(2) Genomic selection offers two new opportunities: as the potential genetic gain can be almost doubled, more traits can be efficiently selected; phenotype recording can be decoupled from selection and limited to several thousand animals. (3) Additional information from other traits can be used, either from existing traditional recording systems at the farm level or from the recent and rapid development of new technologies and precision farming. Milk composition (i.e. mainly fatty acids) should be adapted to better meet human nutritional requirements. Fatty acids can be measured through a new interpretation of the usual medium infrared spectra. Milk composition can also provide additional information about reproduction and health. Modern milk recorders also provide new information, that is, on milking speed or on the shape of milking curves. Electronic devices measuring physiological or activity parameters can predict physiological status like estrus or diseases, and can record behavioral traits. Slaughterhouse data may permit effective selection on carcass traits. Efficient observatories should be set up for early detection of new emerging genetic defects. In the near future, social acceptance of cattle production could depend on its capacity to decrease its ecological footprint. The first solution consists in increasing survival and longevity to reduce replacement needs and the number of nonproductive animals. At the individual level, selection on rumen activity may lead to decreased methane production and concomitantly to improved feed efficiency. A major effort should be dedicated to this new field of research and particularly to rumen flora metagenomics. Low input in cattle production is very important and tomorrow's cow will need to adapt to a less intensive production environment, particularly lower feed quality and limited care. Finally, global climate change will increase pathogen pressure, thus more accurate predictors for disease resistance will be required.