Published in Scientific Papers. Series D. Animal Science, Vol. LXIII, Issue 2
Written by Ion BUZU, Silvia EVTODIENCO, Petru LIUŢKANOV
The purpose of the present research was to reveal and evidence the genotypic particularities of the type(race) of sheep Moldavian Karakul. The experiments were performed on sheep populations from the Experimental Household of the National Institute of Zootechnics and Veterinary Medicine (INZMV), and from the Agricultural Cooperative of Production "Agrosargal", Republic of Moldova. Research they demonstrated that the hereditary capabilities of the Moldavian Karakul sheep are well genetically consolidated and are constantly transmitted through descent. In particular, the morpho-productive characters, which determine the quality of the furskin, have significant genotypic (mother-descendant) correlations, such as: loop length (r=0.47±0.08; tr=5.9; P<0.001); extension of the loop (r=0.45±0.09; tr=5.6; P<0.001); silk fiber (r=0.40±0.09; tr=4.4; P<0.001); fiber luster (r=0.30±0.10; tr=3,0; P<0,01); fiber length (r=0.30±0.10; tr=3.0; P<0.01); body length of lamb at birth (r=0.36±0.02; tr=18.0; P<0.001); body mass of lamb at birth (r=0.30±0.03; tr=10.0; P<0.001) and evaluation class (r=0.48±0.07; tr=6.8; P<0.001). The large body mass of the sheep (meat production aptitude) is constantly transmitted through heredity. There is an obvious genotypic correlation between this character of the father-rams and the young-descendants (r=0.55±0.09). The heritability coefficient of body mass is not high (2=0.3), but quite significant (tr=2.6; P<0.01). The value of the repeatability coefficient (rw) of body mass at different ages of young sheep and adult sheep is 0.23–0.47. The consolidated genotypic capacities of the Moldavian Karakul sheep are also manifested in the transmission through heredity milk production. The value of the heritability coefficient (2) of this character is not high, but quite significant (2=0.316; P<0.001). Most breeding rams have valuable hereditary capabilities. Out of the total 112 rams tested for descendants qualities, 30 rams were recognized as improvers, which is 26.8%. The genotypic qualities of improvers have been repeatedly confirmed. The type of sheep Moldavian Karakul possesses a karyotype with specific genetic characteristics, which is identified by the classical Asian Karakul race and the local race Tusca, after the erythrocyte antigenic markers of the 7 blood groups (A, B, C, D, M , R and I), which include 15 erythrocyte antigens (Aa, Ab, Bb, Bd, Bg, Be, Bi, Ca, Cb, Da, Ma, R, O, I and i). Moldavian Karakul sheep are characterized by a high frequency (0.6005-0.9504) of antigens Bb, Bd, Bg, Be, Ca, Cb, Da, Ma, O and I, a medium frequency (0.3447-0.5796) of antigens Aa and R, as well as a reduced frequency (0.0496-0.2260) of antigens Ab, Bi and i. In the diagram of the genetic clusters, the sheep population Moldavian Karakul occupies an intermediate position in cluster B with the genetic distance of 0.2586, located between the two related populations, as is the local breed Tusca of the cluster A with the genetic distance of 0.1280 and, the race Asian Karakul from cluster C with genetic distance of 0.3154. In the population studied were found 136 genotypes and 48 genetic allele with specific frequencies. The degree of homozygosity of the investigated population constitutes 0.58, which shows sufficient genetic consolidation for the growth "in itself".
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