Crossbreeding of sheep under semi-arid conditions

Abstract

Data were obtained on 3028 lambs born during five successive years from 1961 to 1966 at Ras El-Hekma Desert Research Station in the Western Coastal Egyptian Desert. Breed groups involved in the study were Hungarian Merino, Syrian Awassi, native Barki sheep, and nine of their crosses. The characters studied were birth weight, weaning and yearling weights, pre-and post-weaning average daily gain and yearling greasy fleece weight. The effects of breed group, year of birth, sex, age of dam and type of birth on these characters were investigated. The results obtained showed that Barki lambs excelled Merino lambs in all the traits related to body growth. Merino lambs, on the other hand, excelled Barkis in fleece weight. Barki lambs also excelled Awassi lambs in all traits except birth and weaning weights. In all characters except pre-weaning gain, the first cross of Merino and Barki (^M^B) was markedly superior to all the other crosses and pure breeds. The two third-crosses, | M | B and | M | B , were similar to each other in their productive traits and were slightly inferior to the first cross. The two back-crosses, 4:M£B and fM^B, were markedly different from each other, the former being better than the latter. The three-eighths Merino group is suggested for developing a new strain of sheep for the semi-arid regions. The effects of the environmental factors on the six characters studied were all highly significant except for the effect of sex on fleece weight and the effects of age of dam and type of birth on growth from weaning to yearling ages. The most important factor affecting the different traits was year of birth. Type of birth and age of dam were important sources of variation only for the characters studied till weaning age, but became of little importance thereafter. The effect of sex was pronounced only on yearling weight.

Effects of crossbreeding and certain environmental factors on multiple births, wool production and growth in sheep

“…The present superiority of the reciprocal crosses over the Oxford and Suffolk breeds was estimated at 17 % which compares fairly well with the 21% and 17% estimates reported by Fahmy, Galal, Ghanem and Khishin (1969) for crosses among Merino, Barki and Awassi sheep but was higher than the 6% estimate reported by Donald et al (1963) for crosses among Blackface and Swaledale breeds. The present superiority of the reciprocal crosses over the Oxford and Suffolk breeds was estimated at 17 % which compares fairly well with the 21% and 17% estimates reported by Fahmy, Galal, Ghanem and Khishin (1969) for crosses among Merino, Barki and Awassi sheep but was higher than the 6% estimate reported by Donald et al (1963) for crosses among Blackface and Swaledale breeds.…”

Crossing Merino and a coarse wool breed of sheep; a study of the birthcoat of lambs

“…Fahmy et al (1969), in an earlier study of the birth, weaning, yearling weights and the greasy fleece weight of the same flock, considered the f M and £ M as the most promising in the crosses. From the study of the fibre type arrays in the present work, the birthcoat of the £ M might be considered the best combination of the Merino crosses with the Barki.…”

“…The animals therefore be valuable for selecting among lambs at were kept in the research station where a crossing an early age, and more especially for deciding programme using combing wool Merino (Ghanem, whether to continue to cross with Merinos. The 1965) had been going on since 1958 to improve the studies of birthcoat fibre type arrays (Goot, 1941), wool production of the local coarse wool Barki also throw new light on the probable course of evo- (Fahmy et al 1969). Parallel to crossing, a selection lution in the coat of sheep.…”

Influence of live weight, sex and type of birth on growth and slaughter characteristics in early weaned lambs

“…Other researchers (Mavrogenis, 1996;Kumar et al, 2008) have reported that male lambs from different breeds and at any age had higher live weight and better growth performance than females. The reasons for the higher growth rate of male lambs were the sex hormones (Fahmy et al, 1969) and faster skeletal development than in females (Abbas et al, 2010). However, in the experiment of Manso et al (1996) female lambs were born with lower live weight but after weaning at 37 days of age, they grew faster than males.…”