Effect of the X chromosome in genomic evaluations of reproductive traits in beef cattle

Author(s)

Solar Diaz, Iara Del Pilar ^[1] ; Ferreira de Camargo, Gregorio Miguel ^[1] ; Rocha da Cruz, Valdecy Aparecida ^[1] ; Hermisdorff, Isis da Costa ^[1] ; Damasceno Carvalho, Caio Victor ^[2] ; de Albuquerque, Lucia Galvao ^[3] ; Costa, Raphael Bermal ^[1]

Affiliation

^[1] Univ Fed Bahia UFBA, Escola Med Vet & Zootecnia, BR-40170110 Salvador, BA - Brazil

^[2] Univ Fed Oeste Bahia UFOB, Barra, BA - Brazil

^[3] Univ Estadual Paulista UNESP, Fac Ciencias Agr & Vet, Dept Zootecnia, Jaboticabal, SP - Brazil

• Document type: Journal article
• Source: Animal Reproduction Science; v. 225, FEB 2021.
• Web of Science Citations: 1

Abstract

The aim of this study was to evaluate whether there are predictive advantages for breeding values with inclusion of X chromosome genomic markers for reproductive (occurrence of early pregnancy - P16 and age at first calving - AFC) and andrological (scrotal circumference -SC) variables in beef cattle. There were 3263 genotypes of females and males evaluated. There were breeding value estimates for SC, AFC and P16 considering two scenarios: 1) only autosomal markers or 2) autosomal and X chromosome markers. To evaluate effects of inclusion of X chromosome markers on selection, responses to selection were compared including or not including genomic marker information from the X chromosome. There were greater heritability estimates for SC (0.40 and 0.31), AFC (0.11 and 0.09) and P16 (0.43 and 0.38) when analyses included, compared with not including, genomic marker information from the X chromosome. When selection is based on results from analyses that did not include information for the X chromosome, there was about a 7 % lesser mean genomic breeding value for the SC traits for selected animals. For P16, there was an approximate 4% lesser breeding value without inclusion of genomic marker information from the X chromosome, while this inclusion did not have as great an effect on the breeding value for AFC. There was an average predictive correlation of 0.79, 0.98 and 0.84 for SC, AFC and P16, respectively. These estimates indicate inclusion of the X chromosome genomic marker information in the analysis can improve prediction of genomic breeding values, especially for SC. (AU)

• FAPESP's process: 09/16118-5 - Genomic tools to genetic improvement of direct economic important traits in Nelore cattle
• Grantee: Lucia Galvão de Albuquerque
• Support Opportunities: Research Projects - Thematic Grants