Nutrient composition and in vitro methane production of sub-tropical grass species in transitional rangeland of South Africa

2018 ◽  
Vol 40 (1) ◽  
pp. 1 ◽  
Author(s):  
C. J. L. du Toit ◽  
W. A. van Niekerk ◽  
H. H. Meissner ◽  
L. J. Erasmus ◽  
L. Morey
Keyword(s):  
South Africa ◽  
Greenhouse Gas ◽  
Ecological Status ◽  
Livestock Production ◽  
Mitigation Strategies ◽  
Greenhouse Gas Mitigation ◽  
Grass Species ◽  
Ch4 Production ◽  
Tropical Grass

The development of greenhouse gas mitigation strategies has become an important issue globally. Enteric methane (CH4) emissions from livestock do not only contribute substantially to the environmental footprint of livestock production but it also represents a loss of energy that could be channelled towards animal growth and production. In this study 14 sub-tropical grass species typical of transitional rangeland regions of South Africa were characterised in terms of ecological status, chemical composition, in vitro total gas and CH4 production. The aim of the study was 2-fold: to identify grass species that could be selected for low enteric CH4 production; evaluate the influence of rangeland ecological status on the methanogenic potential of a rangeland. Grass samples were collected by hand, air-dried, milled and analysed for nutrient composition, in vitro organic matter digestibility (IVOMD) and in vitro gas and CH4 production. Cenchrus ciliaris and Urelytrum agropyriodes produced the highest 48-h in vitro CH4 of 17.49 and 14.05 mL/g DM digested respectively. The lowest 48-h in vitro CH4 was produced by Andropogan gayanus and Bothriochloa bladhii with 5.98 and 6.08 mL/g DM digested respectively. The evaluated grass species were overall of poor quality with low CP concentrations ranging from 2.4% for Trachypogon spicatus to 6.7% for Digitaria eriantha and IVOMD ranging from 22.5% for Andropogon gayanus to 42.2% for Urelytrum agropyriodes. Decreaser grass species presented with higher in vitro CH4 production compared with Increaser I and Increaser II grass species in the present study. The results of the study emphasise the importance of including the nutritional potential of grass species for improved livestock production when evaluating grass species for possible greenhouse gas mitigation strategies.

scholarly journals In Vitro Evaluation of Different Dietary Methane Mitigation Strategies

Animals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 1120 ◽  
Author(s):  
Juana C. Chagas ◽  
Mohammad Ramin ◽  
Sophie J. Krizsan
Keyword(s):  
Control Diet ◽  
Mitigation Strategies ◽  
Ch4 Emissions ◽  
Ch4 Production ◽  
Wide Range ◽  
Fermentation Parameters ◽  
Propynoic Acid ◽  
Dietary Strategies

We assessed and ranked different dietary strategies for mitigating methane (CH4) emissions and other fermentation parameters, using an automated gas system in two in vitro experiments. In experiment 1, a wide range of dietary CH4 mitigation strategies was tested. In experiment 2, the two most promising CH4 inhibitory compounds from experiment 1 were tested in a dose-response study. In experiment 1, the chemical compounds 2-nitroethanol, nitrate, propynoic acid, p-coumaric acid, bromoform, and Asparagopsis taxiformis (AT) decreased predicted in vivo CH4 production (1.30, 21.3, 13.9, 24.2, 2.00, and 0.20 mL/g DM, respectively) compared with the control diet (38.7 mL/g DM). The 2-nitroethanol and AT treatments had lower molar proportions of acetate and higher molar proportions of propionate and butyrate compared with the control diet. In experiment 2, predicted in vivo CH4 production decreased curvilinearly, molar proportions of acetate decreased, and propionate and butyrate proportions increased curvilinearly with increased levels of AT and 2-nitroethanol. Thus 2-nitroethanol and AT were the most efficient strategies to reduce CH4 emissions in vitro, and AT inclusion additionally showed a strong dose-dependent CH4 mitigating effect, with the least impact on rumen fermentation parameters.

A review of whole farm-system analysis in evaluating greenhouse-gas mitigation strategies from livestock production systems

2018 ◽  
Vol 58 (6) ◽  
pp. 980 ◽  
Author(s):  
Richard Rawnsley ◽  
Robyn A. Dynes ◽  
Karen M. Christie ◽  
Matthew Tom Harrison ◽  
Natalie A. Doran-Browne ◽  
...  
Keyword(s):  
Greenhouse Gas ◽  
Production Systems ◽  
Ghg Emissions ◽  
Livestock Production ◽  
Mitigation Strategies ◽  
System Level ◽  
Food Demand ◽  
Ghg Mitigation ◽  
Farm System ◽  
Global Food

Recognition is increasingly given to the need of improving agricultural production and efficiency to meet growing global food demand, while minimising environmental impacts. Livestock forms an important component of global food production and is a significant contributor to anthropogenic greenhouse-gas (GHG) emissions. As such, livestock production systems (LPS) are coming under increasing pressure to lower their emissions. In developed countries, LPS have been gradually reducing their emissions per unit of product (emissions intensity; EI) over time through improvements in production efficiency. However, the global challenge of reducing net emissions (NE) from livestock requires that the rate of decline in EI surpasses the productivity increases required to satisfy global food demand. Mechanistic and dynamic whole farm-system models can be used to estimate farm-gate GHG emissions and to quantify the likely changes in farm NE, EI, farm productivity and farm profitability as a result of applying various mitigation strategies. Such models are also used to understand the complex interactions at the farm-system level and to account for how component mitigation strategies perform within the complexity of these interactions, which is often overlooked when GHG mitigation research is performed only at the component level. The results of such analyses can be used in extension activities and to encourage adoption, increase awareness and in assisting policy makers. The present paper reviews how whole farm-system modelling has been used to assess GHG mitigation strategies, and the importance of understanding metrics and allocation approaches when assessing GHG emissions from LPS.

scholarly journals Evaluation of Stylosanthes scabra Accessions as Forage Source for Ruminants: Growth Performance, Nutritive Value and In Vitro Ruminal Fermentation

Animals ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1939
Author(s):  
Thamsanqa Doctor Empire Mpanza ◽  
Abubeker Hassen ◽  
Abiodun Mayowa Akanmu
Keyword(s):  
South Africa ◽  
Growth Performance ◽  
Crude Protein ◽  
Nutritive Value ◽  
Livestock Production ◽  
Metabolizable Energy ◽  
Forage Yield ◽  
Ruminal Fermentation ◽  
Stylosanthes Scabra

Feed shortage is the main cause of poor production performance in livestock under smallholder farmer’s in South Africa. Therefore, this study evaluated the growth performance, nutritive value and in vitro ruminal fermentation of Stylosanthes scabra accessions in climatic condition of Pretoria, South Africa as potential forage sources in order to improve feed quality and subsequently livestock production. Stylosanthes scabra accessions were planted in 6 m2 plots following a complete randomized block design with three replicates per accession. The plants were allowed to grow to full maturity after which forage was harvested and yield, chemical composition, phenolic compounds, in vitro organic matter digestibility (IVOMD) and in vitro ruminal fermentation characteristic were determined. Forage yield of accessions ranged between 4.3 to 5.3 t ha−1 in dry matter (DM), and only twelve accessions were identified to be adaptable over the three-year evaluation under rain-fed. Accessions 140, 9281, 11,252, 11,595, 11,604 and 11,625 were consistent in terms of forage yield over the three years. Significant differences among accessions were observed for crude protein (CP), neutral detergent fiber (NDF), IVOMD, metabolizable energy, metabolizable energy yield, gas production, total phenols, total hydrolysable tannins and total condensed tannins. Principal component and clustering analysis showed that accessions 11,255 and 11,625 are distinct in their characteristics as compared to the rest of the accessions, and both accessions are suitable forage source for animals since they contain low NDF with good forage production and crude protein content. However, there is a need for further study to integrate these accessions into the feeding systems in order to improve livestock production.

Greenhouse gas emissions from livestock production: modelling methods, methane emission factors and mitigation strategies

2021 ◽  
pp. 25-54
Author(s):  
Donal O’Brien ◽  
◽  
Laurence Shalloo ◽  
Keyword(s):  
Life Cycle Assessment ◽  
Life Cycle ◽  
Greenhouse Gas ◽  
Methane Emission ◽  
Livestock Production ◽  
Emission Factors ◽  
Mitigation Strategies ◽  
Gas Emissions ◽  
Modelling Methods ◽  
Production Modelling

This chapter discusses the systems analysis and life cycle assessment modelling approaches and also looks at a range of model applications. These applications include use within the national inventories of various countries across species including discussions around the use of different emission factors. The chapter concludes with applications to quantify emissions at the farm level and a discussion around some of the mitigation strategies that have been modelled previously.

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