REPEATABILITY ESTIMATES OF SOME PRODUCTIVE AND REPRODUCTIVE TRAITS IN RED SINDHI
CATTLE
Muhammad
Iqbal Mustafa, Muhammad Khalid Bashir1, Arfan Yousaf2
and Bashir Ahmad
Department of livestock Management,
1Department of Animal
Breeding and Genetics, 2Department of Clinical Medicine and
Surgery, University of Agriculture Faisalabad
Abstract
The breeding records of 179 Red Sindhi cattle maintained at the Livestock
Experiment Station Hab Choki, Balochistan, during the years 1982-97 were used in
the present study. An effort was made to estimate the repeatability for some
productive and reproductive traits by using the Mixed model least squares and
maximum likelihood procedures. The repeatability estimates for milk yield,
lactation length, dry period, service period, gestation period and calving
interval were 0.361 ± 0.05, 0.03 ± 0.05, 0.029 ± 0.06, 0.17± 0.06, 0.94 ± 0.55
and 0.167 ± 0.06, respectively in model 1, whereas in model 2 estimates for milk
yield, lactation length, dry period, Service period, gestation period and
calving interval were 0.354 ± 0.05. 0.041 ± 0.05, 0.040 ± 0.06, 0.173 ± 0.06,
0.98 ± 0.056 and 0.165 ± 0.06, respectively. The repeatability estimates are
used in determining the amount of culling that can be safely done on the basis
of records. A high estimate of repeatability provides enough evidence for
selection or rejection of the individual based on single record. Whereas a low
estimate of repeatability justifies accumulation of further records. A moderate
estimate of repeatability (0.361) for lactation milk yield obtained in the
present study indicates that the cows can be selected for milk yield on the
basis of relatively lesser records in the present herd
Key words:
Repeatability, productive and reproductive traits, Red Sindhi cattle.