Use of Test-Day Milk Yield for Genetic Evaluation in Dairy Cattle: A Review
G. Bilal and M.
S. Khan1
University
College
of
Veterinary
and Animal Sciences,
Islamia
University
of
Bahawalpur;
1Department of Animal Breeding and Genetics,
University
of
Agriculture,
Faisalabad,
Pakistan
Abstract
The
use of appropriate method for genetic evaluation of dairy animals is an
important aspect of dairy cattle production. Traditional 305-day lactation model
does not account for the changes in environmental factors within 305-day
lactation and may involve unjustified projection of incomplete lactations. The
use of test-day model in the recent past has made it possible to economize the
genetic evaluation with a better accuracy. This paper reviews the recent
developments in genetic evaluation of dairy cattle in the developed production
set ups and explores the possibility of using test-day model for genetic
evaluation of dairy cattle in
Pakistan.
Different options within test-model approach are also discussed. This is
expected to provide food for thought in place in countries like
Pakistan
where production recording and genetic evaluation systems are getting.
Key words:
Test-day milk yield, genetic evaluation, dairy cattle, test-day model.
