This study investigated the impact of nine polymorphisms located in the CSN2, CSN3, CSN1S1, CSN1S2, OLR1, LALBA, STAT1, DGAT1 and LGB genes, and environmental factors including calving year, season and parity on reproductive traits. The analysis was conducted on 165…
Mean daily milk yield for 478 Holstein-Friesian cows from two herds, recorded between 1984-1985, and for 218 Jersey cows from two herds, recorded between 1984-1985, were used to estimate lactation curve parameters for Wood's gamma function: Yn = A nbe-cn.Yn…
Milk yield data (n = 12307) from 116 Holstein-Friesian herds were grouped into three production environments based on mean and standard deviation of herd 305-day milk yield and evaluated for within herd variation using univariate animal model procedures. Variance components…
Dairy cattle semen imported from January 1979 to June 1989 consisted of 72% Holstein-Friesian, 13.6% Jersey, 11.5% Ayrshire and 2.8% Guernsey semen. There has been a significant increase in the importation of Holstein-Friesian semen and, to a lesser extent, in…
The performance of 92 Holstein-Friesian bulls, which were accepted for progeny testing under the South African National Dairy Animal Performance and Progeny Testing Scheme during 1982, 1983 and 1984, was compared. Bulls which were locally bred for more than one…
