Relationship Between the CYP21 Marker and some Productive and Physiological Traits of Holstein-Friesian Cows

Abstract There was a difference in the genetic profiles of CYP21 genotype, it showed three polymorphisms: 250/240, 260/251 and 270/261 bp, their distribution ratios were 51.72, 29.31, 18.96%, respectively. The percentages highly significant differences (P≤0.01), total studied alleles 116. study that there no production milk its components between polymorphisms, as well rate flow. (P≤0.05) different polymorphisms cows heat endurance factor, carrying genotype bp outperformed genotypes so value thermal factor 99.73 for coefficient 101.82 102.43, California test mastitis, bp. values 1.77 1.00 270/261, 250/240 respectively, 2.45.