Assessment of Genetic Diversity and Productive Traits in Crossbreed Cattle in the Caribbean Region, Colombia.

OBJECTIVES

Evaluate the genetic diversity and productive traits of crossbred cattle in the Caribbean region of Colombia, through analyses derived from the assessment of the genome-wide single-nucleotide polymorphism (SNP).

METHODS

A total of 590 individuals and 66,098 SNPs were analyzed by principal components analysis (PCA) and detection of runs of homozygosity (ROH). The population was composed of 531 heifers marked as crossbreed and a group of 59 heifers marked as purebred Gyr. Additionally, allele frequencies were calculated for commercially important traits (, , , , , , , , , , and ).

RESULTS

Global differences in PCA were 7.35%, and principal components explained 1.94% and 5.41% of the variation. Five ROH islands were identified in crossbred animals on chromosomes 2, 5, 7, 8, and 12. The majority of observed ROH classes were shorter than 2 Mb, 54% in crossbreed cattle and 47% in Gyr cattle. Individual inbreeding was 5.2% in crossbreed and 12% in Gyr cattle. Both groups had similar allelic and genotypic frequencies for most of the evaluated commercial traits. Only a wide variation was observed in the genes related to growth hormone () and Calpastatin and ). Crossbreed heifers had desired allele frequencies for better milk production and quality in the genes , , , and , as well as in the genes and .

CONCLUSIONS

Crossbreed cattle in the Colombian Caribbean region possess high genetic diversity and desirable allele frequencies to implement breeding and intense selection programs aimed at improving production yields.