Abstract
The accurate estimates of genetic parameters are essential for making decisions of optimum selection of breeding. The authors have recently developed for actual practice a totalsystem for estimation of breeding values (EBV) with a micro-computor, by which records of the individuals of the swine but also those of their relatives can be counted.
This system based on contemporary comparison method makes it easier to calculate the EBV on the days of age (DAY) and on the back fat thickness (BF) at 105kg of body weight, and also on the reproductive performances such as the number of piglets born alive and the litter weight adjusted for 21 days of age. Therefore, this system has been applied to practical uses by breeders.
On the other hand, the best linear unbiased prediction (BLUP) procedure is widely used for the sire evaluation in dairy and beef cattle due to its accuracy, but this procedure is tedious in its application with microcomputor due to large scale matrix needed for calculation.
The purpose of our present paper is to compare the sire rankings of Duroc breed of swine predicted by the following two procedures, i. e.
1) The application program in our micro-computor system, and
2) BLUP procedure with sire model using large scale computor.
The performance test date on DAY and BF of 4, 852 Duroc pigs sired 45 boars were analyzed.
The results revealed that the percentage of consistency in the top 30% sire rankings obtained by the two methods were in the range from 86% to 93% in both traits, showing the practical usefulness of the simplified method.
