Environmental Factors Affecting Birth Weight And Litter Size In Yankasa Sheep
DOI :
https://doi.org/10.51791/njap.v20i.2096Mots-clés :
Environmental, litter size,, birth weight, Yankasa sheepRésumé
Records on 1634 lambings of a Yankasa sheep flock collected from 1983 to 1990 were used to determine the effects of parity, litter size, sex, season and year of birth on birth weight, and that of parity, season and year of birth on litter size respectively.
Least squares means (± s.e.) for birth weight and litter size were 2.49±0.013kg and 1.22±0.010 respectively. Birth weight was significantly (P<0.01) affected by parity, sex, litter size and season of birth. Lambs born in the late wet season had higher birth weights than those born in other seasons. Also, male and single lambs were heavier at birth than female and twin lambs.
Litter size was significantly (P<0.01) affected by parity, season and year of birth. Late wet season lambing had lower litter size than other seasons.
The repeatability estimates for birth weight and litter size were 0.19±0.028 and 0.01±0.032 respectively while phenotypic correlation between the two traits was -0.249.
