ENVIRONMENTAL FACTORS AFFECTING BIRTH WEIGHT IN LOHI SHEEP
M.E. Babar, Z. Ahmad, A. Nadeem and M. Yaqoob
Faculty of Animal Husbandry,
University
of
Agriculture,
Faisalabad,
Pakistan
Abstract
Data on 3984 lambing records of 1285 Lohi ewes
kept at the Livestock Production
Reserch Institute, Bahadurnagar, Okara for the period 1960-90 were analyzed by
using Harvey’s Mixed Model Least Squares and Maximum Likelihood Computer
Programme. The purpose was to estimate the magnitude of various environmental
sources of variation influencing birth weight in this breed of sheep. The least
squares mean for birth weight was 3.59 ±
0.02 kg. The trait was significantly (P< 0.01) influenced by the year and season
of birth, type of birth and the sex of the lamb born. The age of the dam also
had significant effect on birth weight of the lamb; the younger ewes produced
lighter (3.48 ±
0.02 kg) lambs than older ewes (3.67 ±
0.03 kg).