A. APOSTOLOV1, I. SABEVA1 and E. GINEVA2
1 Agricultural Institute, BG-9700 Shumen, Bulgaria
2 OSZ, BG-8600 Yambol, Bulgaria
APOSTOLOV, A., I. SABEVA and E. GINEVA, 2011. Sources of specific variance and genetic determination of sow longevity and service period in pigs with different origin. Bulg. J. Agric. Sci., 17: 396-401
The purpose of the current study was to estimate variance components and the genetic determination of the sow longevity and the service period in pigs with different origin. The study comprised 2488 sows originated from 137 sires with the following origin: Danube White, Large White with a polish origin and fattening pigs, classified in three different farms. The study was carried out during the period 1999 - 2008. The first ten parities were analyzed. The furrowing seasons were classified in four categories according to the climate determination of the country. The variance analysis, the heritability, as well as the genetic correlations were made according to the methodology of the mixed models. The normal data distribution achieved by logarithmic transformation of the scale of measurements was an objective of an analysis. The phenotypic variation of the sow longevity and the service period were significantly affected by the breed, litter (parity) and year of birth. Low values of heritability for the studied traits (h2 = 0.05) were specified. Average to high values of calculated genetic correlations (rg = 0.6) was the reason to suppose that the selection according to the born alive would positively affect on the sow longevity.