Estimation of genetic parameters for milk productivity and type evaluations of cows from dairy population in Bulgaria | Оценка на генетически параметри за млечна продуктивност и оценки по тип на крави от млечна популация в България
2010
Jonkovski, M., Institute of Mountain Animal Stockbreeding and Agriculture, Troyan (Bulgaria) | Todorov, M., Institute of Mountain Animal Stockbreeding and Agriculture, Troyan (Bulgaria) | Dimov, G., AgroBioInstitute, Sofia (Bulgaria)
This study used data on milk productivity of cows from the dairy population in Bulgaria, a part of which is on an elite herd of the Holstein-Friesian breed. Variance and covariance components for the traits of milk productivity were estimated, additive, constant environmental and phenotypic. The additive variation was the highest and occupied a relatively great part of the phenotypic one. Genetic parameters were calculated – correlations and heritabilities for the same traits. For the cows, in which intensive breeding had been conducted, the correlations were high and negative, therefore they hardly can be used for future prognostication. For milk quantity, h2 was high – 0.51, for fat percentage it was low – 0.007 and for butterfat it was lower than the expected one. For another part of the cows, four methods were used to calculate h2 and variance components for milk productivity. The results obtained from a limited number of data cannot be used directly in breeding practice and they only illustrate the fact that the different methods lead to different estimates of the variance components. Heritabilities were also calculated for traits of evaluated cows by type with three groups of cows from red, black-and-white and brown population of cows in Bulgaria. The cows from the black-and-white population had significantly the highest values.
Show more [+] Less [-]AGROVOC Keywords
Bibliographic information
This bibliographic record has been provided by Institute of Agricultural Economics