Pasteurella haemolytica is a major contributor to neonatal pneumonia in lambs; which continues to be a major problem. Experimentation was conducted to determine the efficacy of vaccinating pregnant ewes to reduce the incidence of pneumonia in newborn lambs. Vaccines utilized in this experimentation included three different commercial Pasteurella haemolytica vaccines intended for use in cattle a...

Ovine uterine artery (UA) endothelial cells (UAEC) maintained in culture to passage 4 retain pregnancy-specific changes in vasodilator production, which in turn is associated with differences in Ca(2+) and ERK 1/2 signaling. The question remains whether this is an accurate portrayal of the situation in vivo, or more simply whether these same signaling responses seen at passage 4 accurately refl...

In Exp. I, 0.5 mg oestradiol or vehicle (0.5 ml absolute ethanol + 0.5 ml 0.9% NaCl) was injected i.v. at 08:00 h on Day 14 (onset of oestrus = Day 0). Blood samples were obtained via a jugular catheter at 30 and 1 min before oestradiol and every 30 min for 10 h afterwards. Plasma was obtained and assayed for 15-keto-13,14-dihydro-PGF-2 alpha (PGFM) by radioimmunoassay. Before oestradiol, PGFM ...

Pregnant ewes were infected in midpregnancy with three isolates of Chlamydia pecorum derived from the feces of healthy lambs from three different farms. Oral infection, alone or together with Fasciola hepatica, did not result in tissue invasion, since all placental and fecal samples were negative for chlamydiae. Intravenous infection resulted in placental infection in 16 of 18 ewes in that chla...

In ruminants, conceptus interferon-tau (IFNT) alters maternal physiology to accommodate a pregnancy. We hypothesized that the effectiveness of IFNT on extending corpus luteum (CL) life span in nonpregnant ewes would depend upon the dose and manner of administration and would be correlated with the response in gene expression in endometrium. We anticipated that IFNT, whether administered im or b...

Groups of adult lactating Border Leicester cross Merino ewes which had lambed in the spring and had been milked mechanically after the lambs had been weaned at birth, were joined with Dorset Horn rams approximately 60 days after parturition. The ewes had been treated with progestogen sponges and pregnant mare’s serum gonadotrophrin (750 and 1500 I.U.) prior to the time of first or second expect...

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...

Thirty-nine multiparous ewes (19 Pelibuey and 20 Romanov × Pelibuey) treated with fluorogestone acetate impregnated intravaginal sponges were used to evaluate the effects of low pregnant mare serum gonadotropin (PMSG) doses and genotype on their reproductive efficiency under heat stress conditions. The sponge treatment lasted for 12 days, and 24 h before sponge removal, ewes of each genotype we...

The effects of an intraruminal load of 3 litres of water on body water movements was compared in Sardi sheep during the last month of pregnancy, lactation and a non-pregnant, non-lactating control period. Before the water load, rumen fluid volume, estimated by polyethylene glycol was similar in pregnant, compared to control, animals and 27% higher in lactating sheep. After the water load, rumen...