I. SABEVA and A. APOSTOLOV
Agricultural Institute, BG - 9700 Shumen, Bulgaria
SABEVA, I. and A. APOSTOLOV, 2012. Longevity of Shagya broodmares. Bulg. J. Agric. Sci., 18: 272-277
The objective of the research was to be established the sources of specific variance and the heritability of the productive life of Shagya broodmares. The data for the length of productive life of 95 broodmares acted at the National stud Kabiuk after 1975 was an object of statistical processing. They were representatives of 8 lines 7 genealogical families and originated from 15 stallions and 63 mares. The analyses of the variance were done by mixed lineal models in which not only the genetic and environmental sources of variation were included, but also the factors: rate of gene plasma from Arabian breed, inbreeding, basic body indices, the exterior estimates and the generational remoteness from the families’ founders.
The factors inbreeding, grading, massiveness, the exterior estimates and the generational remoteness of mares from the families’ founders had decisive influence on the phenotypic variance of the productive life of Shagya broodmares. Typically for all long – term selected breeds of horses, fathers were the main source of genetic variance. With the longest productive life were the mares with Fx from 1.60 to 3.12 %. Estimates over the population average had the Arabian crossbreeds with grading above 50.00%. The superiority of the mares with massiveness above 114% was statistically proven. Average to high heritability of the trait was established (h2 = 0.34).