• HAWAR M. H. ZEBARI Dept.of Animal Production, College of Agricultural Engineering Sciences, University of Duhok, Duhok
Keywords: Karadi ewes; Awassi ewes; synchronized; fertility; conception; parity


Poor reproductive efficiency is considered one of the main causes of declining sheep production in
sheep raised under traditional farm conditions. Many factors contribute to declining reproductive
performance in ewes. The objective of the present study was to investigate factors that affect reproductive
efficiency in Karadi and Awassi sheep raised under farm conditions. Four hundred Karadi and Awassi
sheep (200 Karadi and 200 Awassi) were used in this study. Of each breed 100 ewes were allowed to come
into oestrus spontaneously and another 100 ewes were synchronized using intravaginal sponges. Ewes
were injected with intramuscular injection of 500 IU of PMSG when sponges were removed at 14 days.
This study revealed that the breed had a significant effect on twinning rate and lamb mortality rate in
spontaneous ewes. Breed also had a significant effect on the rate of lambing, lamb mortality, abortion, and
dystocia in synchronized ewes. In addition, parity had a significant effect on the rate of lambing, lamb
mortality and dystocia in spontaneous Karadi and Awassi ewes. Furthermore, parity also had significant
effect on the rate of lambing, lamb mortality, dystocia and barrenness in synchronized Karadi and Awassi
ewes. Different ram to ewe ratio during the oestrus period had a significant effect on conception rate and
barrenness rate in synchronized Karadi and Awassi ewes. In conclusion, breed had effect on some
reproductive parameters in synchronized and spontaneous ewes. Parity 2 had higher reproductive
performance than parity 1 and parity ≥3 ewes. Conception rate were higher in 1:8 ram to ewe ratio group,
while 1:≥16 ram to ewe ratio group had higher barrenness rate.


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How to Cite
ZEBARI, H. M. H. (2020). FACTORS THAT INFLUENCE ON REPRODUCTIVE EFFICIENCY IN KARADI AND AWASSI SHEEP RAISED UNDER TRADITIONAL CONDITIONS. Journal of Duhok University, 23(2), 169-181. https://doi.org/10.26682/ajuod.2020.23.2.20
Agriculture and Veterinary Science