Nasledjivanje mlecnosti u populaciji crno-belog goveceta.
1984
Lazarevic R. | Milojic M. | Latinovic D.
An examination of milk yield of the Holstein-Friesian breed of cows has been carried out in three generations in succession in production conditions. The following has been found: The period of lactation was the same in all generations. The quantities of milk and milk fat grows from the first to the third generation (P less than 0,01) while the content of milk fat has a different tendency (P less than 0,05). The values of the congenitive coefficient, phenotypical correlation and regression are relatively low for the characteristics examined and the differences are insignificant. All the parameters are greater in lactations of 305 days than in the total lactation. The reason for this is the effects of other factors on the production in total lactation. Therefore, for using the relative reproductive values, the data for 305 days of lactation can be used. In milk production, to increase the quality of sires of the future generations is all important and the importance of the sires mothers should not be ignored. Therefore the choice of cows and the reproductive evaluation should be performed in the same way as it is done with sires.
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