Association of the genomic inbreeding coefficient with milk production in Holstein and Jersey cows.

• Grant number: 25/07352-7
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: November 01, 2025
• End date: October 31, 2026
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Genetics and Improvement of Domestic Animals
• Principal Investigator: Josineudson Augusto Ii de Vasconcelos Silva
• Grantee: Luís Gustavo Moreira Silva da Mata
• Host Institution: Faculdade de Medicina Veterinária e Zootecnia (FMVZ). Universidade Estadual Paulista (UNESP). Campus de Botucatu. Botucatu , SP, Brazil

Abstract

Inbreeding in dairy cattle increases homozygosity, favoring the expression of deleterious recessive alleles and resulting in the phenomenon of inbreeding depression, which can compromise the productive and reproductive performance of animals, affecting important characteristics of economic interest to breeders. This research aims to estimate the inbreeding coefficients of Holstein and Jersey cows from pedigree records and genomic data and to evaluate their association with milk, protein, and fat production up to 305 days of the first lactation. The data will be obtained from two dairy farms, initially with the Holstein breed and later with the Jersey breed. Statistical analyses will be conducted using specific programs based on genealogical information, genomic matrix, and homozygosity runs. Linear regression models and scatter plots will be used to evaluate the association with milk, protein, and fat production. With the results, we expect to identify the most inbred animals and their lineages based on the estimated inbreeding coefficients and propose mating recommendations that minimize coancestry, considering additive genetic relatedness. (AU)