Genetic evaluation of Frieswal Frieswal bulls under farm and field conditiions

Abstract

The present investigation was undertaken to determine the genetic worth of Frieswal bulls under farm and field conditions and to asses their rankings in both production systems. The average offirst lactation milk yield in crossbred cows was 2818±47 kg at Military Fanns (Frieswal) and 2489±66 kg at field units. Best linear unbiased prediction (BLUP) estimates of the sires ranged from 2664±72 to 3076±99 kg (accuracy from 0.50 to 0.95) under farm conditions and from 2422±130 to 2633±117 kg (accuracy from 0.53 to 0.88) under field conditions. The product moment correlation (-O.098±O.23) between breeding values of bulls for first lactation milk yield under farm and field conditions was negative, very low and nonsignificant. The corresponding rank correlation (-0.12) was also negative, low and nonsignificant. The results revealed that bulls with higher ranks for milk production under farm conditions did not retain their superiority under field conditions. Therefore, top ranked Frieswal bulls tested under fann conditions cannot be recommended for their use in field conditions.