Breed diversity is a valuable resource of the sheep industry. Crossbreeding systems use breed diversity to increase productivity relative to purebred flocks. Crossbreeding systems vary in managerial complexity and in use of beneficial effects due to crossbred ewes and lambs. Efficiency of meat production is maximized in terminal crossbreeding systems by use of specialized sire breeds to complem...

The reproductive performance of 255 Rambouillet (R), Dorset (D), Finnsheep (F) and F1 ewes born in 1978-1979 (group I) and 1979-1980 (group II) and managed in a semiconfinement fall/winter lambing system was evaluated through 4 yr of age of all ewes and through 5 yr for a portion of group I ewes. Ewes were with rams from approximately May 1 to late September each year, with a 2-wk break late in...

Reproductive performance was evaluated in non-lactating crossbred ewes to which were administered the exogenous GnRH and PMSG. The ewes were randomly allocated in three treatment groups (n=40).After accurate detection of estrus and 2 hours prior to mating, 2.5 mL of distilled water and 2.5 mL of GnRH were injected intramuscular to each ewe of the first (control) and second group, respectively. ...

the effect of daily oral administration of ephedrine (0, 1, 2, 4 or 8 mg kg-1 w0.75) on carcasscharacteristics of forty-four 2 yr old crossbred (mehraban x ghezel) fat-tailed ewes was studied. theewes were fed a fattening ration, and received ephedrine by using a drenching gun for either 50 or 70days. there was a significant interaction (p

Twenty-eight crossbred 2-year-old ewes were used · to determine the effects of pregnancy and lacta­ tion on the body storage of DDT and dieldrin and on their elimination in milk. Pregnancy did not significantly affect total DDT degradation in ewes, but significantly affected dieldrin metaoo­ lism. Body fat from pregnant animals averaged higher in dieldrin concentration at parturition than did t...

Fifty two crossbred ewes conceiving to a synchronised oestrus in January 1987 were ultrasound scanned for littersize and subsequently allocated according to littersize to twogroups (Lupin or Sorghum grain). The ewes grazed on dry Phalaris/clover pastures with supplementation (200 g/h/d) commencing 'at 100 days post conception at a rate of 200 g/h/d and continuing until parturition at which time...

Lambs wool production and qualities from the progeny of 2 Merino and 2 Damara rams mated to Merino ewes were compared. The crossbred lambs produced about half the amount of wool and had high fibre diameter variation and medullated fibre components. Merino lambs wool was contaminated with pigmented and medullated fibres apparently transferred from continual exposure to the Damara crossbred lambs...

Over a 2-year period, crossbred lambs resulting from the mating of Texel (T), Romanov (R), and St. Croix (S) rams with Polypay (P) and S ewes, were finished during the summer and late fall to determine feedlot performance and carcass characteristics. A total of 175 wether lambs of the five genotypes (R x P, R x S, S x S, T x P and T x S) were fed a high-energy diet for an average of 110 d (Expe...