Low levels of taurine introgression in the current Brazilian Nelore and Gir indicine cattle populations

• DOI: 10.1186/s12711-015-0109-5
• Publication Date: 2015-04-16T16:40:29Z
• Authors: Ana M Perez O’Brien; Daniela Höller; Solomon A Boison; Marco Milanesi; Lorenzo Bomba; Yuri T Utsunomiya; Roberto Carvalheiro; Haroldo HR Neves; Marcos VB da Silva; Curtis P VanTassell; Tad S Sonstegard; Gábor Mészáros; Paolo Ajmone-Marsan; Fernando Garcia; Johann Sölkner
• Keywords: Introgression; Zebu

Nelore and Gir are the two most important indicine cattle breeds for production of beef milk in Brazil. Historical records state that these were introduced Brazil from Indian subcontinent, crossed to local taurine order quickly increase population size, then backcrossed original recover adaptive productive traits. Previous investigations based on sparse DNA markers detected admixture breeds. High-density genome-wide analyses can provide high-resolution information genetic composition current populations, estimate more precisely levels nature introgression, shed light their history strategies used expand breeds.We high-density Illumina BovineHD BeadChip with than 777 K single nucleotide polymorphisms (SNPs) reduced 697 115 after quality control filtering investigate structure populations seven other worldwide comparison. Multidimensional scaling model-based ancestry estimation clearly separated indicine, European African ancestries. The average level introgression autosomal genome was less 1% but 9% Brahman breed. Analyses mitochondrial SNPs present did not differentiate haplotype groupings.The low observed both confirms historical crossbreeding supports a strong directional selection against haplotypes via backcrossing. Random sampling herds across country subsequent genotyping would be useful complete view commercial populations.