A prediction equation for enteric methane emission from dairy cows for use in NorFor

Nielsen, N. I.; Volden, H.; Åkerlind, M.; Brask, M.; Hellwing, Anne Louise Frydendahl; Storlien, T. M.; Bertilsson, J.

doi:10.1080/09064702.2013.851275

Cited by 35 publications

(110 citation statements)

References 16 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…With fixed model regression, RMSE was 50.7 and 49.2 for linear and quadratic DMI models and 42.3 for the Karoline model. However, in contrast to the present study, DMI predicted CH 4 emissions better than digestible nutrients estimated by the semi-mechanistic NorFor model (Nielsen et al, 2013). Empirical equations derived by Yan et al (2000) predicted CH 4 emissions from the intake of digestible energy, feeding level and some other dietary factors precisely and accurately (R 2 ¼0.89; RMSE¼11.6%) with their best derived equations.…”

Section: Comparison To Empirical Equationscontrasting

confidence: 98%

Nordic dairy cow model Karoline in predicting methane emissions: 2. Model evaluation

Ramin

Huhtanen

2015

Livestock Science

View full text Add to dashboard Cite

Section: Comparison To Empirical Equationscontrasting

confidence: 98%

Nordic dairy cow model Karoline in predicting methane emissions: 2. Model evaluation

Ramin

Huhtanen

2015

Livestock Science

View full text Add to dashboard Cite

“…A higher R 2 might be expected as measured data for in vivo rumen digested OM converted to VFA, as well as measured molar proportions of VFA were used as an input for the calculations. However, it was well within R 2 obtained with other models predicting CH 4 production from intake parameters (Yan et al, 2009;Nielsen et al, 2013) and most likely caused by variation in the measurement of rumen VFA and OM digestion as demonstrated before in a theoretical simulation study by Bannink et al (2006). Using l CH 4 /kg DMI as the unit strongly decreased variation compared with l CH 4 /day because DMI is the major determinant for variation in CH 4 production.…”

Section: Discussionsupporting

confidence: 84%

Methane production and diurnal variation measured in dairy cows and predicted from fermentation pattern and nutrient or carbon flow

Brask

Weisbjerg

Hellwing

et al. 2015

Animal

Self Cite

View full text Add to dashboard Cite

Many feeding trials have been conducted to quantify enteric methane (CH 4 ) production in ruminants. Although a relationship between diet composition, rumen fermentation and CH 4 production is generally accepted, the efforts to quantify this relationship within the same experiment remain scarce. In the present study, a data set was compiled from the results of three intensive respiration chamber trials with lactating rumen and intestinal fistulated Holstein cows, including measurements of rumen and intestinal digestion, rumen fermentation parameters and CH 4 production. Two approaches were used to calculate CH 4 from observations: (1) a rumen organic matter (OM) balance was derived from OM intake and duodenal organic matter flow (DOM) distinguishing various nutrients and (2) a rumen carbon balance was derived from carbon intake and duodenal carbon flow (DCARB). Duodenal flow was corrected for endogenous matter, and contribution of fermentation in the large intestine was accounted for. Hydrogen (H 2 ) arising from fermentation was calculated using the fermentation pattern measured in rumen fluid. CH 4 was calculated from H 2 production corrected for H 2 use with biohydrogenation of fatty acids. The DOM model overestimated CH 4 /kg dry matter intake (DMI) by 6.1% ( R 2 = 0.36) and the DCARB model underestimated CH 4 /kg DMI by 0.4% ( R 2 = 0.43). A stepwise regression of the difference between measured and calculated daily CH 4 production was conducted to examine explanations for the deviance. Dietary carbohydrate composition and rumen carbohydrate digestion were the main sources of inaccuracies for both models. Furthermore, differences were related to rumen ammonia concentration with the DOM model and to rumen pH and dietary fat with the DCARB model. Adding these parameters to the models and performing a multiple regression against observed daily CH 4 production resulted in R 2 of 0.66 and 0.72 for DOM and DCARB models, respectively. The diurnal pattern of CH 4 production followed that of rumen volatile fatty acid (VFA) concentration and the CH 4 to CO 2 production ratio, but was inverse to rumen pH and the rumen hydrogen balance calculated from 4 × (acetate + butyrate)/2 × (propionate + valerate). In conclusion, the amount of feed fermented was the most important factor determining variations in CH 4 production between animals, diets and during the day. Interactions between feed components, VFA absorption rates and variation between animals seemed to be factors that were complicating the accurate prediction of CH 4 . Using a ruminal carbon balance appeared to predict CH 4 production just as well as calculations based on rumen digestion of individual nutrients.Keywords: modelling methane, VFA, enteric fermentation, carbon, dairy cow Implications Methane (CH 4 ) is a potent greenhouse gas that arises from feed fermentation in the rumen and large intestine of ruminant animals. The quantity of CH 4 depends on daily feed intake, feed chemical composition and feed rumen digestibility. Therefore, the present paper was ...

show abstract

“…Therefore, the total dietary NDF variable in the Nielsen et al . () equations was modified to represent dNDF. The average total tract digestibility of NDF in the data used by Nielsen et al .…”

Section: Methodsmentioning

confidence: 99%

“…The average total tract digestibility of NDF in the data used by Nielsen et al . () was about 70%, so the regression coefficients of dietary gross NDF (% of DM) in the original equations were modified accordingly [0.12 vs. 0.171 (0.12 × 1/0.70)] as shown below:

Original equation false[normalE 27 false] : {CH}_{4} false(MJ {day}^{- 1} false) = 1.23 \times DMI false(kg {day}^{- 1} false) - 1.45 \times FA + 0.120 \times NDF

Modified equation false[normalE 28 false] : {CH}_{4} false(MJ {day}^{- 1} false) = 1.23 \times DMI false(kg {day}^{- 1} false) - 1.45 \times FA + 0.171 \times dNDF

…”

Section: Methodsmentioning

confidence: 99%

Models for predicting enteric methane emissions from dairy cows in North America, Europe, and Australia and New Zealand

Appuhamy

France

Kebreab

2016

Global Change Biology

117

View full text Add to dashboard Cite

There are several models in the literature for predicting enteric methane (CH4 ) emissions. These models were often developed on region or country-specific data and may not be able to predict the emissions successfully in every region. The majority of extant models require dry matter intake (DMI) of individual animals, which is not routinely measured. The objectives of this study were to (i) evaluate performance of extant models in predicting enteric CH4 emissions from dairy cows in North America (NA), Europe (EU), and Australia and New Zealand (AUNZ) and (ii) explore the performance using estimated DMI. Forty extant models were challenged on 55, 105, and 52 enteric CH4 measurements (g per lactating cow per day) from NA, EU, and AUNZ, respectively. The models were ranked using root mean square prediction error as a percentage of the average observed value (RMSPE) and concordance correlation coefficient (CCC). A modified model of Nielsen et al. (Acta Agriculturae Scand Section A, 63, 2013 and 126) using DMI, and dietary digestible neutral detergent fiber and fatty acid contents as predictor variables, were ranked highest in NA (RMSPE = 13.1% and CCC = 0.78). The gross energy intake-based model of Yan et al. (Livestock Production Science, 64, 2000 and 253) and the updated IPCC Tier 2 model were ranked highest in EU (RMSPE = 11.0% and CCC = 0.66) and AUNZ (RMSPE = 15.6% and CCC = 0.75), respectively. DMI of cows in NA and EU was estimated satisfactorily with body weight and fat-corrected milk yield data (RMSPE < 12.0% and CCC > 0.60). Using estimated DMI, the Nielsen et al. (2013) (RMSPE = 12.7 and CCC = 0.79) and Yan et al. (2000) (RMSPE = 13.7 and CCC = 0.50) models still predicted emissions in respective regions well. Enteric CH4 emissions from dairy cows can be predicted successfully (i.e., RMSPE < 15%), if DMI can be estimated with reasonable accuracy (i.e., RMSPE < 10%).

show abstract

A prediction equation for enteric methane emission from dairy cows for use in NorFor

Cited by 35 publications

References 16 publications

Nordic dairy cow model Karoline in predicting methane emissions: 2. Model evaluation

Nordic dairy cow model Karoline in predicting methane emissions: 2. Model evaluation

Methane production and diurnal variation measured in dairy cows and predicted from fermentation pattern and nutrient or carbon flow

Models for predicting enteric methane emissions from dairy cows in North America, Europe, and Australia and New Zealand

Contact Info

Product

Resources

About