Study Concerning the Determination of Causal Components of Variance for Bioeconomic and Ecoeconomic Characters in Frasinet Carp Breed

Abstract

Increased competitiveness in the biological fish material market required the improving the quantitative characters of exploited species. One of the essential problems of heredity study quantitative characters is knowledge of the degree of hereditary transmission of characters from parents to offspring. This requires knowledge of the causal components of variance. The biological material studied consisted of 50 descendants who came from five mothers and 10 fathers. Each descendant was measured for three characters: body weight, maximum body height and body length at the end of the first three summers of growth. For variance components analysis was used BLUP (Best Linear Unbiased Prediction) methodology, applied to an individual animal model. The results showed that the characteristics considered their genetic determinism is low to medium. Thus, it was found that body weight is low genetic determinism (0.1662-0.1758). Maximum height of the body had an average genetic determinism after the first and the third summer of growth (0.3108, 0.2434) and low genetic determinism after the second summer (0.1697). Body length had an average genetic determinism (0.2698) after the first summer of growth and quite low genetic determinism afterwards (0.1293, 0.1297). A low value of heritability means a low genetic progress; due to the fact the selection effect is dependent on heritability. In conclusion, for maximizing the effect of heritability, implicitly the genetic progress of considered characters will have to practice a family selection witch, in addition to the candidate's own performance to contribute to family average intake.