A Basic Model to Predict Enteric Methane Emission from Dairy Cows and Its Application to Update Operational Models for the National Inventory in Norway

The aim of this study was to develop a basic model to predict enteric methane emission from dairy cows and to update operational calculations for the national inventory in Norway. Basic models were developed using a database with 63 treatment means from 19 studies. The database included records for enteric CH4 production (MJ/day), dry matter intake (DMI), and dietary nutrient composition. The basic models were evaluated against an external database (n=36, from ten studies) along with other extant models. When evaluated by low root mean square prediction errors and high concordance correlation coefficients, the developed basic models that included DMI, dietary concentrations of fatty acids and neutral detergent fiber performed slightly better in predicting CH4 emissions than extant models. In order to propose country-specific values for the CH4 conversion factor Ym (% of gross energy intake partitioned into CH4) and thus to carry out the national inventory for Norway, the existing operational model was updated for the prediction of Ym over a wide range of feeding situations using energy corrected milk and dietary concentrate share as predictor variables. Input values of Ym were updated based on the results from the basic models. The predicted Ym ranged from 6.22 to 6.72%. In conclusion, the prediction of CH4 production from dairy cows was improved with the help of newly published data, which enabled an update of the operational model for calculating the national inventory of CH4 in Norway.

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A Basic Model to Predict Enteric Methane Emission from Dairy Cows and Its Application to Update Operational Models for the National Inventory in Norway

Animals ◽

10.3390/ani11071891 ◽

2021 ◽

Vol 11 (7) ◽

pp. 1891

Author(s):

Puchun Niu ◽

Angela Schwarm ◽

Helge Bonesmo ◽

Alemayehu Kidane ◽

Bente Aspeholen Åby ◽

...

Keyword(s):

Dairy Cows ◽

Energy Intake ◽

Methane Emission ◽

Neutral Detergent Fiber ◽

Operational Model ◽

National Inventory ◽

Basic Model ◽

Ch4 Production ◽

Enteric Methane ◽

Gross Energy

The aim of this study was to develop a basic model to predict enteric methane emission from dairy cows and to update operational calculations for the national inventory in Norway. Development of basic models utilized information that is available only from feeding experiments. Basic models were developed using a database with 63 treatment means from 19 studies and were evaluated against an external database (n = 36, from 10 studies) along with other extant models. In total, the basic model database included 99 treatment means from 29 studies with records for enteric CH4 production (MJ/day), dry matter intake (DMI) and dietary nutrient composition. When evaluated by low root mean square prediction errors and high concordance correlation coefficients, the developed basic models that included DMI, dietary concentrations of fatty acids and neutral detergent fiber performed slightly better in predicting CH4 emissions than extant models. In order to propose country-specific values for the CH4 conversion factor Ym (% of gross energy intake partitioned into CH4) and thus to be able to carry out the national inventory for Norway, the existing operational model was updated for the prediction of Ym over a wide range of feeding situations. A simulated operational database containing CH4 production (predicted by the basic model), feed intake and composition, Ym and gross energy intake (GEI), in addition to the predictor variables energy corrected milk yield and dietary concentrate share were used to develop an operational model. Input values of Ym were updated based on the results from the basic models. The predicted Ym ranged from 6.22 to 6.72%. In conclusion, the prediction accuracy of CH4 production from dairy cows was improved with the help of newly published data, which enabled an update of the operational model for calculating the national inventory of CH4 in Norway.

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Forage and Flax Seed Impact on Enteric Methane Emission in Dairy Cows

Research Journal of Veterinary Sciences ◽

10.3923/rjvs.2011.1.8 ◽

2011 ◽

Vol 4 (1) ◽

pp. 1-8 ◽

Cited By ~ 7

Author(s):

V. Sejian ◽

J. Lakritz ◽

T. Ezeji ◽

R. Lal

Keyword(s):

Dairy Cows ◽

Methane Emission ◽

Flax Seed ◽

Enteric Methane

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Individual milk fatty acids are potential predictors of enteric methane emissions from dairy cows fed a wide range of diets: Approach by meta-analysis

Journal of Dairy Science ◽

10.3168/jds.2018-15940 ◽

2019 ◽

Vol 102 (11) ◽

pp. 10616-10631 ◽

Cited By ~ 3

Author(s):

A. Bougouin ◽

J. A. D. Ranga Niroshan Appuhamy ◽

A. Ferlay ◽

E. Kebreab ◽

C. Martin ◽

...

Keyword(s):

Fatty Acids ◽

Dairy Cows ◽

Meta Analysis ◽

Methane Emissions ◽

Milk Fatty Acids ◽

Wide Range ◽

Enteric Methane ◽

Enteric Methane Emissions

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Methane emissions of dairy cows cannot be predicted by the concentrations of C8:0 and total C18 fatty acids in milk

Animal Production Science ◽

10.1071/an14292 ◽

2014 ◽

Vol 54 (10) ◽

pp. 1757 ◽

Cited By ~ 23

Author(s):

S. R. O. Williams ◽

P. J. Moate ◽

M. H. Deighton ◽

M. C. Hannah ◽

W. J. Wales

Keyword(s):

Fatty Acids ◽

Dairy Cows ◽

Milk Fat ◽

Methane Emissions ◽

Published Data ◽

Efficiency Coefficient ◽

Ch4 Emissions ◽

General Linear Model Analysis ◽

Wide Range ◽

Prediction Regions

Methane (CH4) emissions from dairy cows are technically difficult and expensive to measure. Recently, some researchers have found correlations between the concentrations of specific fatty acids in milk fat and the CH4 emissions from cows that could obviate the need for direct measurement. In this research, data on individual cow CH4 emissions and concentration of caprylic acid (C8:0) and total C18 fatty acids in milk were collated from eight experiments involving 27 forage-based diets and 246 Holstein-Friesian dairy cows. Linear regressions between CH4 and both C8:0 and total C18 in milk were produced for published data and used to calculate 95% prediction regions for a new observation. The proportion of observed methane emissions from eight experiments that fell outside the 95% prediction region was 27.6% for the C8:0 model and 26.3% for the total C18 model. Neither model predicted CH4 emission well with Lin’s coefficient of concordance of less than 0.4 and the Nash–Sutcliffe efficiency coefficient of approximately zero for both the C8:0 and total C18 models. In addition, general linear model analysis showed significant differences between experiments in their intercepts (P < 0.001) and slopes (P < 0.001). It is concluded that the relationships tested cannot be used to accurately predict CH4 emissions when cows are fed a wide range of diets.

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