Genotypical and allelic frequencies of the κappa caseína gene in cattle of Reyna breed, Managua, Nicaragua

Abstract

The present work was carried out in the Creole cattle of the Reyna breed of the animal science faculty. This breed has been important in the development of Central American livestock, in principle it was the founding herd of it. The Reyna cattle, is a breed adapted to the tropical conditions of Nicaragua, selected by Joaquín Reyna in the year 1920. The κ-casein protein is related to milk production and quality characteristics, such as, cheese yield, time of coagulation, firmness of micelle and high levels of lactoferrin. Milk derived from animals CASκ AA genotype has a lower percentage of κ-casein, on the contrary, milk from CASκ BB animals has a higher proportion of κ-casein and smaller micelles. The present study aimed to determine the genotypic and allelic frequencies of the kappa-casein gene (κ-CN) in cattle of the Reyna breed. 22 blood samples were collected in breeding females from the Santa Rosa farm of the Animal Science Faculty of the National Agrarian University (UNA). The kappa casein gene was amplified by PCR technique, with primers BLKC-For 5`-ATTAGCCCATTTCGCCTTCT-3` and BLKC-Rev 5`-ATT TATGGCCATTCCACCAA-3`, obtaining a fragment of 351 bp. The alleles were identified using the PCR-FRLP technique, obtaining genotypic frequencies of 0.090, 0.045 and 0.863 for the AA, BB and AB genotypes, respectively. Allelic frequency was 0.52 and 0.48 for alleles A and B respectively, indicating greater number of AB and AA genotypes.