GENOMIC ASSOCIATION STUDY FOR STAYABILITY IN NELLORE CATTLE, IN DIFFERENTS CALVINS

• Grant number: 17/24272-0
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2018
• End date: December 31, 2018
• Field of knowledge: Agronomical Sciences - Animal Husbandry - Genetics and Improvement of Domestic Animals
• Agreement: Coordination of Improvement of Higher Education Personnel (CAPES)
• Principal Investigator: Lucia Galvão de Albuquerque
• Grantee: Diogo Osmar Silva
• Host Institution: Faculdade de Ciências Agrárias e Veterinárias (FCAV). Universidade Estadual Paulista (UNESP). Campus de Jaboticabal. Jaboticabal , SP, Brazil

Abstract

It is economically important that the cows remain for a longer period in the herd, since the possibility of returning the investment of the rearing costs of the heifers for the replacement of the herd is greater. Stayability (STAY) is one of the traits used to evaluate the longevity of the cows. Defined as the presence or not of the cow in the herd up to a specific age, STAY is a binary trait, which is expressed only after a predetermined age. Therefore it is a late expression phenotype, since the interest is usually focused on ages above 64 months. The evaluation of sires for this trait depends on information from relatives, especially daughters, which increases the generation interval. In this sense, the identification of the regions of the genome associated with the expression of this trait, in different calvings, can provide subsidies for a better understanding of the inheritance of this trait and its use in breeding programs. Thus, the present project aims to carry out a study of genomic association using the trait stayability measured in different calvings in Nelore cattle. For this, we will use phenotypic data and the pedigree information of about 200,000 cows coming from farms that integrate three breeding programs. A total of 3,869 genotypes were available, of which 2,974 animals (2,025 cows and 949 sires) were obtained using a panel of 777,962 SNPs (Illumina BovineHD BeadChip) markers, and 895 animals (715 cows and 180 sires) genotyped using a panel GeneSeek® Genomic Profiler Indicus HD-GGP75Ki (NEOGEN), containing 74,677 markers. The analyzes of the genomic association for each calving will be performed using single-step GBLUP (Genomic Best Linear Unbiased Predictor), which allows to include information of all animals with known phenotypes and genotypes in a single step. A threshold model will be used, given the categorical distribution of the characteristic, with contemporany groups as fixed effects and random additive and residual genetic effects. With the results, it is desired to identify regions of the genome that influence the expression of this trait and to investigate common genomic regions related to STAY obtained in different calving, which will allow a better understanding and definition of the studied trait.

Academic Publications

(References retrieved automatically from State of São Paulo Research Institutions)

SILVA, Diogo Osmar. Genome-wide association study for stayability in Nelore cattle, considering different ages. 2018. Master's Dissertation - Universidade Estadual Paulista (Unesp). Faculdade de Ciências Agrárias e Veterinárias. Jaboticabal Jaboticabal.