Abstract
Data on 918 Sahiwal cows, the progeny of 35 sires, were
used to estimate heritabilities of some measures of milk yield
by the method of paternal half-sib correlation. The first lactation 305-day milk yield (FLMY), milk yield per day of first
calving interval (MYFCI) and milk yield per day of age at second calving (MYASC) averaged 1603.29 ± 12.32, 3.87 ±0.04 and
1.01 ± 0.01 kg, respectively. Heritabiliir estimates for FLMY,
MYFCI and MYASC were 0.11 ± 0.07, -0.01 ± 0.04 and 0.10 ±
0.07, respectively. These estimates indicated that FLMY is a
better indicdtor of cow's transmitting ability than MYFClor
MYASC and be preferably used in the selection of young
cows.