Prediction of methane emission from lactating dairy cows using milk fatty acids and mid-infrared spectroscopy: a review.

We reviewed recent literature that relates milk fatty acids with methane emission, and discussed the potential use of mid-infrared (MIR) spectroscopy to estimate methane emission of dairy cattle. A summary of studies that investigated the predictive power of milk fatty acids for methane emission indicated good potential. Note that this relationship between milk fatty acids and methane emission is diet specific, and that the discrepancies between studies can be the result of the different methane expression units (e.g. per unit feed or per unit product).

Until recently, gas chromatography was the principal method used to determine the milk fatty acid profile, but this method is unsuitable for routine analysis. This has led to the application of MIR; an inexpensive, non-destructive, rapid and multi-parametric technique already routinely used in milk recording systems worldwide to predict fat, protein, lactose and urea contents in dairy milk.

The major advantages of using MIR spectroscopy to predict methane emission include its simplicity and potential practical application at large scale. Two important disadvantages are (1) the inability to predict important milk fatty acids for methane prediction (e.g. lower abundant milk fatty acids that appear in various methane prediction equations published), and (2) the moderate predictive power for methane emission. The review concludes that it may not be sufficient to predict methane emission based on MIR alone. Integration with other factors, like feed intake, nutrient composition of the feed, parity, and lactation stage may improve the prediction of methane emission using MIR spectra.

Please find a link to the article in Journal of the Science of Food and Agriculture: http://onlinelibrary.wiley.com/doi/10.1002/jsfa.7718/full

For more information, please contact: sanne.vangastelen@wur.nl