Effect of Polymorphism of Calpastatin gene, Age on meat Tenderness for Carcasses in Local Awassi sheep

ABSTRACT
This study was conducted in the farm of animals, of the College of Agriculture, University of
Baghdad as well as Genetic Resources Laboratories Unit, Animal Resources Department, Ministry
of Agriculture and Biotechnology Research Center, AL- Nahrain University, during the period
15/7/2014 until 01/4/2015.The aim of the study was to determine the genotypes gene of Calpastatin
and the statement of the effect of genotypes on the local Awassi sheep carcasses, and studying the
relationship of sex of animal with a number of qualitative characteristics of sheep meat. The study
used 40 animals of local Awassi sheep (20 males and 20 females) homogeneous reconstructed. The
study included blood and flesh samples of Longissimus dorsal muscle (LD) and Femoris muscle
Biceps (BF). Polymerase Chain Reaction technique (PCR) and PCR-RFLP were used, by the use of
Restriction enzyme MspΙ, to identify the genotypes of the Calpastatin gene . The distribution
percentage of polymorphism accounted for gene of Calpastatin in the sample studied of Awassi sheep
were 75.00, 22.50 and 2.50% for each of the genotypes MM, MN and NN, respectively. The variation
among these percentages were highly significant and the emergence of the two alleles M and N and
the repetition of allele M was 0.86 and allele N stood at 0.14. The quality of Organoleptic gene, as
the effect of the genotype gene "Calpastatin", was significant (P≤0.05) in recipes of flavor and
juiciness. So it distinguish the genotype NN with loudest 5:00 and 3:16 values, respectively, after
the genotypes MN and MM excelled both genotypes carriers for the allele N on the pure MM
genotype in the recipe of flavor and juiciness. General qualities of tenderness and receptivity was not
affected morally with different genotypes of the gene. However, the difference in age was high
significantly emerged (P≤0.01) on each sensory qualities (flavor, tenderness, juiciness and public
acceptance), reaching the highest value for the recipe flavored at age 2-4 years (4.83). The highest
value for the mellowness was at age 1-2 years, It amounted 3.18 and showed the highest value of
prescription juiciness at age 1-2 years (2.95), while other ages (2-4 years and more than 4 years)
were 2.27 and 2.74, respectively.