In ewes, the uterine gland knockout (UGKO) phenotype is caused by neonatal exposure to norgestomet to arrest uterine gland development and produce an adult which has a uterus characterized by the lack of endometrial glands. Since endometrial glands in the sheep produce the lymphocyte-inhibitory protein, ovine uterine serpin (OvUS), an experiment was conducted with ewes of the UGKO phenotype to ...

A study was done to test whether ovulatory follicles destined to form subfunctional corpora lutea differed from normal ovulatory follicles in steroidogenic function. Twenty-five ewes were treated with prostaglandin F2 alpha on d 11 of the estrous cycle, then unilaterally ovariectomized before (n = 13) or after (n = 12) the surge of luteinizing hormone (LH) at the induced estrus to collect "cont...

To investigate the influence of maternal Se supply and plane of nutrition on lamb morbidity, mortality, and passive transfer of IgG, pregnant ewe lambs were used in 2 experiments with 2 × 3 factorial treatment arrangements. Supplementation of Se began at breeding and was either adequate Se (ASe, 9.5 μg/kg of BW) or high Se (HSe, 81.8 μg/kg of BW) in Exp. 1 or ASe (11.5 µg/kg of BW) or HSe (77.0...

Estradiol (E2), estrone (El ) , progesterone, LH and prolactin concentrations were determined by radioimmunoassay in blood plasma samples from parous ewes treated with medroxyprogesterone acetate (MAP) or melengestrol acetate (MGA) orally, with MAP by intravaginal sponge, or progesterone by intramuscular injection. Treatment was begun on Day 10 of the estrous cycle and continued for 14 days. Bl...

In Exp. 1, 45 fine-wool ewes received (sc) either 0, 50 or 100 mg epostane (3-beta-hydroxysteroid dehydrogenase inhibitor) to examine effects on return to estrus and conception rates. Treatments were imposed on d 10 of an estrous cycle (estrus = d 0) and jugular blood samples were collected once daily on d 8 and 9, twice daily on d 10 through 13 and once daily from d 14 until first post-treatme...

The effects of progestogen-gonadotropin treatment on estrous response, ovulation rate and lambing response of crossbred ewes were examined at two times during the anestrous season (May-June and July-August). Each ewe group was treated with progestogen pessaries for 16 days and injected with 750 IU pregnant mare serum gonadotropin (PMSG) on days 17 and 32 to induce two consecutive estrous period...

O NE hundred seventy-nine ewe lambs from a three-breed polyallel cross involving the Willamette, Suffolk and Hampshire breeds were used to study the genetic aspects of fertility. Ewe birth weight, ewe weight at mating and fertility were analyzed in relation to heterosis, general combining ability, maternal effect, reciprocal differences, and the effects of a hormone treatment. Treatment consist...

Ewes were injected intramuscularly with 1 ml iodised oil at mating or during the first two months of pregnancy to determine if marginal iodine deficiency contributed to the high mortality of newborn lambs in Victoria. Iodine treatment markedly increased milk iodine concentration of ewes. In nine of ten trials conducted in 1979 and 1980 at Ararat, Hamilton, Langi Kal Kal, Ruffy, Rutherglen and T...

The effects of early weaning and exogenous hormones on postpartum estrus, conception and lambing performance were evaluated with 124 fall-lambed Karakul ewes. The broad outline of the experiment consisted of two lactation periods (nursing for 48 hr or 60 days postpartum) and four hormone treatment groups as follows: (1) a single injection of 2 mg estradiol-17/3 on day 4 postpartum and on the sa...

Mature pregnant crossbred ewes (n = 90) were used in a randomized complete block design and assigned to 1 of 3 winter-feeding systems differing in primary feed source: haylage (HL), limit-fed corn (CN), or limit-fed dried distillers grains (DDGS). Effects of these winter-feeding strategies on ewe and lamb performance were determined. Diets were formulated to meet or exceed NRC (1985) nutrient r...