Zootechnical parameters added to the milk MIR spectra as predictive value to estimate CH4 emissions


  • Vanlierde A. , Dehareng F. , Gengler N. , Froidmont E. , McParland S. , Kreuzer M. , Bell M. , Lund P. , Martin C. , Kuhla B. & Soyeurt H. (2019). Zootechnical parameters added to the milk MIR spectra as predictive value to estimate CH4 emissions. Proceedings in: EAAP, Ghent, August 2019, Book of Abstracts of the 70th Annual Meeting of the European Federation of Animal Science,
Type Conference Proceedings
Year of conference 2019
Title Zootechnical parameters added to the milk MIR spectra as predictive value to estimate CH4 emissions
Conference name EAAP
Conference location Ghent
Publisher Book of Abstracts of the 70th Annual Meeting of the European Federation of Animal Science
conference Date August 2019
Abstract Breeding sector needs tools to permit large scale quantification of GHG emissions, and to develop levers to reduce them. Milk mid-infrared (MIR) spectrum is an interesting proxy to estimate individual daily methane (CH4) emissions of dairy cow. A model has been developed based on 1,089 reference measurements combining milk MIR spectra and CH4 value, collected using the SF6 tracer technique (n=513) and the respiration chambers (n=576). These data are from 7 countries (BE, IRL, CH, UK, FR, DK and D) and from cows of 5 major breeds: Holstein (74%), Brown Swiss (13%), Jersey (3%), Red Holstein (3%) and Sweedish Red Crossed (2.5%). Statistics reached a R² and a SE of 5 groups cross-validation (CV) of 0.64 and 61 g of CH4/day respectively. A cow and country dependent external validation (CCDEV) has been performed: all the data from 20% of the cows per country are removed, calibration is done on the 80% remaining cows from all countries and validated on the 20% removed. After 500 repetitions, the R² and the RMSEP of CCDEV were of 0.55 ± 0.07 and 70 ± 4.5 g of CH4/day respectively. To improve these results new calibrations have been developed with zootechnical parameters available in routine added to the milk MIR spectra as predictive value. Parity, milk yield and breed information have been used individually and each possible combination of them leading to 7 new calibrations. Statistics were improved with the increasing of parameters considered with an optimum for the version combining these 3 parameters in addition to the milk MIR spectra as predictors, reaching a R²cv of 0.68, a SECV of 57 g of CH4/day, and R² and RMSEP of CCDEV of 0.6 ± 0.06 and 65 ± 4.1 respectively. Considering these routinely available parameters improve the statistics of the model. Practical applications are required to observe and compare the relevance of their predictions.
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Authors Vanlierde A. , Dehareng F. , Gengler N. , Froidmont E. , McParland S. , Kreuzer M. , Bell M. , Lund P. , Martin C. , Kuhla B. & Soyeurt H.