Genomic approach to manage genetic variability in dairy farms

In this study we investigated the genetic variability, inbreeding and allele frequencies of monogenic traits in seven herds Holstein breed provided insight to farmers on value genomic management reproduction their herds. A total 3,953 cows were sampled genotyped with Neogen GGP Bovine 100K SNP chip within activities Regione Lombardia funded GO-PEI project ‘GENOmic tool for dairy cattle control – GENORIP’. Principal component analysis was applied analysing variability among farms using SVS software Golden Helix. Run Homozygosity (ROH) obtained detectRUNS package R software. Genotype mendelian disease, fertility production also obtained. 458,267 ROH identified distributed all autosomes an average length 2,703,811 bp covering 12.7% genome. Several regions appear under selection, while a specific region BTA4 one herd, harbouring genes mainly related selection strategy farmer. The FROH values considering greater than 16 Mb, varied from 0.004 0.325, highest 0.136. Among heritable diseases, Haplotype Cholesterol Deficiency largest proportion carrier animals, i.e. 5.6%. herd-tailored process assist released. distribution together genotype traits, suggest that similar directional is occurring across This released each farmer make-up herd used jointly gEBV estimated by national breeders’ association (ANAFIBJ) reproductive management.