DefinePK

Abstract

ABSTRACT This study was carried out to investigate reproductive traits of Kivircik ewes under three lambing systems in two years and their lambs’ survival and growth performances. A total of 200 Kivircik ewes and 15 Kivircik rams were used. Ewes were subjected to a system of lambing every 8 months. Ewes were mated in August (summer), April (spring) and December (winter), respectively. Ewes were synchronized using FIS (intravaginal flourogestone sponges) for 14 days. Additionally, 600 IU eCG (equine chorionic gonadotropin) was administered intramuscularly at sponges withdrawal. Rams remained with the ewes for 3-day from the start of estrus. Estrus rate, lambing rate and litter size were 96.00, 87.50% and 1.70 lamb/doe; 92.35, 85.20 and 1.50 lamb/doe; 78.92, 58.38 and 1.43 lamb/doe for summer, spring and winter seasons, respectively. Survival rates at weaning, birth and weaning weights of lambs were 86.44%, 3.11kg and 17.85kg; 72.80%, 3.24kg and 16.38kg; 66.88%, 3.38kg and 18.97kg for summer, spring and winter, respectively. The effect of mating season on estrus rate was not significant (P>0.05). The effect of mating season on lambing rate and litter size was significant (P<0.01). The effects of mating season and birth type on survival rate at weaning were significant (P<0.05). Effect of mating season on body weights at birth and weaning was significant (P<0.01). The findings of the current study that the reproductivity of Kivircik ewes (in three lambing in two years) synchronized with combination of eCG and FIS tended to improve. Lambing rate and litter size were the highest in the first mating season and the lowest in the third mating season. Lambing rate in the second mating season was similar to that in the first mating season. Survival of lambs at weaning was the highest in the first lambing season and the lowest in the third lambing season. Weaning weight was the highest in the third lambing season and the lowest in the second lambing season. These results also indicate that three lambing system in two years could be utilized in Kivircik sheep.