DNA methylation profiles in bovine sperm are associated with daughter fertility.

The current decline in dairy cattle fertility has resulted in significant financial losses for dairy farmers. In the past, most efforts to improve dairy cattle fertility have been focused on either management or genetics, while epigenetics have received less attention. In this study, 12 bulls were selected from a provided 100 bull list and studied (High daughter fertility = 6, Low daughter fertility = 6) for Enzymatic methylation sequencing in the Illumina HiSeq platform according to the Canadian daughter fertility index (DFI), sires with high and low daughter fertility have average DFI of 92 and 112.6, respectively. And the bull list provided shows a mean DFI of 103.4. 252 CpGs with methylation differences greater than 20% (q < 0.01) were identified, as well as the top 10 promising DMRs with a 15% methylation difference (q < 1.1e-26 ). Interestingly, the DMCs and DMRs were found to be distributed more on the X chromosome than on the autosome, and they were covered by gene clusters linked to germ cell formation and development. In conclusion, these findings could enhance our ability to make informed decisions when deciding on superior bulls and advance our understanding of paternal epigenetic inheritance.