in this study, we aimed to investigate reproductive performance in estrus-induced zandi ewes treated with equine chorionic gonadotrophin (ecg) injection in combination with prostaglandin f2α (pgf2α)and gonadotrophin releasing hormone (gnrh) during non-breeding season. the estrous cycle was synchronized using controlled internal drug release (cidr) for 12 days. the ewes were randomly assigned to...

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. ...

in this study, we aimed to investigate reproductive performance in estrus-induced zandi ewes treated with equine chorionic gonadotrophin (ecg) injection in combination with prostaglandin f2α (pgf2α)and gonadotrophin releasing hormone (gnrh) during non-breeding season. the estrous cycle was synchronized using controlled internal drug release (cidr) for 12 days. the ewes were randomly assigned to...

Ewes from lines selected for high and low reproductive rate and a control line bred and selected randomly were endoscopically examined 3 to 5 d after breeding to determine ovulation rates in the fall of 1985, 1986 and 1987. Fertility (ewes lambing per ewe exposed), lambing rate (lambs born per ewe exposed) and litter size (lambs born per ewe lambing) were evaluated at lambing in the spring of e...

Observations were carried out at Lismore in western Victoria on the performance of two groups of 250 fine wool Merino ewes mated in spring (November) and autumn (May) respectively. A greater proportion of ewes lambing in spring lambed within 150-170 days after the introduction of the rams than ewes lambing in autumn. The duration of lambing was shorter in spring. There were no significant diffe...

Two-hundred-fifty-six crossbred and Targhee ewes which lambed in February and March were randomly assigned to a 38or 73-day postpartum weaning group and within weaning group to a control, an 8or a 16-day progestogen treatment. Treatment was an intravaginal progestogen pessary for 7 days after weaning or for 15 days beginning 8 days before weaning with a 10 mg injection of progesterone on the da...

BACKGROUND The effect of different thawing procedures for ram semen frozen in minitubes and mini straws on the fertility of sheep was tested in a field trial. METHODS Altogether, 719 Norwegian Crossbred ewes, aged between six months and six-and-a-half years from 8 farms, were inseminated vaginally in natural oestrus with frozen-thawed semen. Minitubes were thawed at 70 degrees C for 8 sec (T7...

This paper describes a procedure of laparoscopic insemination (LAI) performed in 42 Ile de France ewes with deep-frozen rams’ semen. Frozen semen doses was imported from France, originating from two rams (A and B), and used intermittently in three LAI cycles on different females. The ewes were examined ultrasonographically for pregnancy, two months following insemination and data of lambing wer...

using melatoninin ewes of iran black breed, this study aimed to compare the reproduction and production performances in lambing program of two and three times per years for duration of two years. a hundred ewes allocated to two parallel groups: group a (ewes in three lambing managing system using melatonin) and group b (ewes in two lambing managing system without using melatonin). to induce the...

Three experiments were conducted, using 1,488 ewes during seasonal anestrous and during the normal estrous period, to evaluate the influence of breed on response to exogenous hormones. Treatment was intravaginal, progestogen pessaries Days 1 to 16, 10 mg crystalline progesterone on Day 16, followed by 750 IU PMS on Day 17. In the anestrous ewes a second PMS injection was given on Day 32 in one ...