Factors affecting the reproductive performance of Awassi sheep flocks in north-east of Jordan: An epidemiological study

Abstract

A prospective cohort study was conducted using 32 randomly selected Awassi sheep flocks to identify factors hypothesized to be associated with the occurrence of pregnancy, twinning and fetal loss between August 2005 and May 2006 in the region of Al-Safawi (northeast of Jordan). Vitamins A and E and selenium concentrations were determined on 448 blood samples. Using the forward selection procedure of the logistic regression module, models with statistically significant risk factors (P < 0.05) were constructed for three outcomes; pregnancy, twinning and fetal loss. Serum vitamin A concentration levels were associated with pregnancy (OR = 2.26, 2.48), twinning (OR = 6.49, 17.74) and fetal loss (OR = 0.13, 0.19). Primiparous ewes were 48% less likely to become pregnant than fourth or higher parity ewes. The likelihood of twinning increased significantly in ewes up to the third parity. Ewes that were fed 700-900 g barley, 250-300 g wheat-bran per head per day and grazed on vegetables residues were 4.15 times more likely to have twins than ewes that were fed 600 g barley and 200 g wheat-bran per head per day. Fetal loss in first and second parity ewes was about 3 times more likely than that in third or higher-parity ewes. Ewes pregnant with twins were about 14 times more likely to have fetal loss than ewes carrying single fetus. Pregnant ewes of the stationary flocks were 37% less likely to have fetal loss than ewes of the semi-nomadic flocks. These results demonstrate that stationary Awassi sheep flocks had higher pregnancy and twinning rates and less pregnancy loss. Supplementation of vitamin A, providing sufficient quantity of dry feed and increasing ram: ewe ratio for primiparous ewes of semi-nomadic flocks is essential to improve Awassi sheep reproductive performance.

Mini review: breeding Awassi and Assaf sheep for diverse management conditions

“…Prolificacy of the Local Awassi is low, about 1.1 lamb born/ ewe lambing (LB/EL), as recently confirmed in several studies reporting 1.18 LB/EL in multiparous Local Awassi sheep (n=2,959) raised by Bedouins in the Negev region of Israel Albaqain et al 2010), and 1.08-1.16 LB/EL in Local Awassi ewes in three studies conducted in Jordan (Kridli et al 2007;Lafi et al 2009;Jawasreh et al 2010).…”

“…By improving environmental conditions, Local Awassi output can be increased, as was demonstrated in Jordan where stationary rather semi-nomadic management and the provision of supplemented feeds were suggested to support improvements in fertility, twinning rate, and lamb survival (Lafi et al 2009). However, like other traditional breeds (Moav et al 1976), the Local Awassi has a limited capacity to respond to an increase in management input.…”

Awassi sheep reproduction and milk production: review

“…The reproductive performance of Awassi ewes has been low in the semi-arid regions of the near east countries (Hamadeh et al 2001;Husein and Kridli 2002). Under normal conditions, less than 10% of Awassi ewes lamb twice a year (Lafi et al 2009). A study was conducted by Kridli et al (2007c) on 3-to 6-year-old pluriparous Awassi ewes (n=56) bred during June and July reported 60.7% (34/56) pregnancy rate, 91% (31/34) single birth rate, 9% (3/34) multiple birth rate, 90% lambing rate (number of lambs born per ewe mated), and 1.08 fecundity (number of lambs born per ewe lambing).…”

Different Endometritis Treatments in Ewe: Comparative Study

“…Sheep form an important part of the livestock in Iraq, and sheep Awassi is the most important strain in the semi-arid lands of the Middle East countries [1]. Reproductive failure occurs in many different forms, as failure to return to heat, repeat breeding and small litter size and, sometimes, even severe disorders may be difficult to detect clinically.…”