ABSTRACT
The objective of this work was to evaluate the genetic diversity of the HSP-70.1 gene and to associate the polymorphisms found with the performance of Holstein, Girolando (5/8H-G) and Sindi dairy cows raised in region of the Brazilian semiarid. Polymorphisms were identified and evaluated using the PCR-RFLP technique using the EcoRII restriction enzyme. Genetic variability was evaluated using the standard diversity index and molecular variance analysis (AMOVA). The identified polymorphisms were evaluated on the characteristics of milk production. They were identified from the seven alleles, demonstrating that there was polymorphism for the analyzed gene region and some alleles were shared among the herds. The Holstein and Sindi bovine breeds were genetically like the analyzed gene. AMOVA demonstrated that there is genetic variation between and within the herds, with most of the variation occurring within the herds for all groups evaluated. There was effect of the alleles identified on the production of milk herds of Holstein and (P<0.0001) Girolando (P<0.0117) breeds. The HSP-70.1 gene was polymorphic in the population of dairy cattle studied, and therefore a promising molecular marker to evaluate milk production of breeds created in semiarid regions.
Keywords:
Dairy cattle; Heat stress; EcoRII; PCR-RFLP
