Can greenhouse gases in breath be used to genetically improve feed efficiency of dairy cows?

Abstract

There is considerable interest in improving feed utilization of dairy cattle while limiting losses to the environment (i.e., greenhouse gases, GHG). To breed for feed-efficient or climate-friendly cattle, it is first necessary to obtain accurate estimates of genetic parameters and correlations of feed intake, greenhouse gases, and production traits. Reducing dry matter take (DMI) requirements while maintaining production has high economic value to farmers, but DMI is costly to record and thus limited to small research or nucleus herds. Conversely, enteric methane (CH 4 ) currently has no economic value, is also costly to record, and is limited to small experimental trials. However, breath gas concentrations of methane (CH 4 c) and carbon dioxide (CO 2 c) are relatively cheap to measure at high throughput under commercial conditions by installing sniffers in automated milking stations. The objective of this study was to assess the genetic correlations between DMI, body weight (BW), fat-and protein-corrected milk yield (FPCM), and GHG-related traits: CH 4 c and CO 2 c from Denmark (DNK) and the Netherlands (NLD). A second objective was to assess the genetic potential for improving feed efficiency and the added benefits of using CH 4 c and CO 2 c as indicators. Feed intake data were available on 703 primiparous cows in DNK and 524 in NLD; CH 4 c and CO 2 c records were available on 434 primiparous cows in DNK and 656 in NLD. The GHG-related traits were heritable (e.g., CH 4 c h 2 : DNK = 0.26, NLD = 0.15) but were differentially genetically correlated with DMI and feed efficiency in both magnitude and sign, depending on the population and the definition of feed efficiency. Across feed efficiency traits and DMI, having bulls with 100 daughters with FPCM, BW, and GHG traits resulted in sufficiently high accuracy to almost negate the need for DMI records. Despite differences in genetic correlation structure, the relatively cheap GHG-related traits showed considerable potential for improving the accuracy of breeding values of highly valuable feed intake and feed efficiency traits.

Breeding for reduced methane emission and feed-efficient Holstein cows: An international response

“…Genetic correlations were positive and moderate between MeP and MY (0.29), and between MeP and ECM (0.45), the first was similar to the correlation reported (0.26) by Breider et al (2018) in Australian Holstein whereas the latter was similar to the correlation reported (0.43) by Lassen and Løvendahl (2016) in Danish Holstein. Likewise, Difford et al (2020) reported genetic correlation of 0.35 between CH 4 concentration and FPCM in a combined data set with Danish and Dutch Holstein cows. Furthermore, genetic correlations between GSMet and MY (0.41) and ECM (0.59) were higher than with MeP.…”

“…Furthermore, CH 4 data (from research and commercial herds) were filtered to only include weekly averages where a maximum of 3 d were missing within each week of measurement and each cow had a minimum of 3 weekly measurements. The concordance correlation coefficient between respiration chamber CH 4 emissions and sniffers (Guardian) CH 4 concentration is 0.77 (Difford et al, 2020). Both methodologies were described and compared previously (Difford et al, 2016).…”

“…Denmark. A total of 14,013 weekly records on CH 4 concentration (ppm) from 2,725 cows were available from DCRC (1,328) and 10 commercial farms (1,397) in Denmark collected between 2011 and 2016, described previously in Zetouni et al (2018) and Difford et al (2016Difford et al ( , 2020. Methane concentration was measured by 2 sniffer methods: the nondispersive infrared CH 4 sensor (Guardian NG, Edinburgh Instruments Ltd.) in the research farms and the portable Fourier transform infrared Gasmet DX-4000 (Gasmet, Gasmet Technologies Oy) in the commercial farms.…”

“…Only a few studies (Lassen and Løvendahl, 2016;Breider et al, 2018;Difford et al, 2020) have reported genetic correlations between MeP and BW in dairy cattle. Furthermore, we have not found studies that reported genetic correlation estimates between MeP and ∆BW.…”

The genetics of phenotypic plasticity in livestock in the era of climate change: a review

“…Today, however, increased demand for food, forces breeders to raise high producing livestock breeds which convert animal feed into meat, milk and eggs (Pirlo and Car e 2013). Furthermore, these high producing breeds are very often held responsible of GHG emissions, even if several studies demonstrated the possibility for using GHG traits as large-scale indicator traits for genetically improving the accuracy of feed efficiency such as in dairy cows (Difford et al 2020), in beef cattle (Barwick et al 2019), in pigs (Alfonso 2019), and in poultry (Willems et al 2013). This may lead to the negligence of local breeds adapted in developing countries (Mathias and Mundy 2005).…”