Sequence-based GWAS of heat tolerance traits in Holstein and Montbeliarde cattle.
Abstract
Global warming will affect European cattle production systems, decreasing overall performance and welfare. In
such a context, it is thus relevant to identify genomic regions involved in heat tolerance for production and functional
traits. By combining the French bovine genetic database (focusing on French Holstein and Montbéliarde
dairy cattle) with weather conditions (Safran database, Meteo-France), we estimated breeding values (BV) of animals
along a temperature-humidity index (THI) gradient with a reaction-norm model. Heat tolerance traits were
defined as the slope of BV at THI 70 for three traits: test-day milk yield, conception rate at first insemination, and
somatic cell score. 50K SNPs from 4564 Holstein and 1737 Montbéliarde bulls were imputed to whole genome
sequence using the run9 of the 1000 bull genomes project, resulting in ~13 million SNPs (R2 Minimac ≥ 0.2 and
MAF ≥ 0.01) to perform within-breed GWAS of heat tolerance for the three traits. Few genomic regions were
significantly associated with heat tolerance, however these regions differed between breeds and traits. Beyond
revealing novel regions associated to heat tolerance, our study also identified some regions already reported in
previous studies, emphasizing their relevance. Finally, given the genetic background of heat tolerance in both production
and functional traits, selection for heat tolerance should be considered. This study received funding from
the European Union’s Horizon 2020 research and innovation program under grant number 101000226 (Rumigen)
and from APIS-GENE (CAICalor). The authors thank Meteo-France for the Safran database.
Domains
Animal geneticsOrigin | Files produced by the author(s) |
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