Search Results

You are looking at 1 - 3 of 3 items for

  • Author: D. G. EDGAR x
Clear All Modify Search
Free access

D. G. EDGAR

Summary.

Possibly because more dividing ova failed to implant in them, a higher proportion of young than of mature ewes returned to oestrus following mating. Apparently, dividing ova tended to reach the uterus earlier in the young ewes, perhaps because of the early relaxation of the utero-tubal junction due to a lower oestrogen secretion.

Free access

E. M. ROBERTS and D. G. EDGAR

Summary.

One hundred 6- and 7-year-old Romney ewes were treated for 13 days in January (mid-summer) with intra-vaginal sponges containing 40 mg of 6-methyl-17-acetoxyprogesterone (map). All ewes received 1000 i.u. pregnant mares serum gonadotrophin (pmsg) on the day of sponge removal and fifty ewes received a second 1000 i.u. pmsg 16 days later.

The onset of oestrus was synchronized in both treatment groups and was apparently 2 weeks earlier than in twenty untreated ewes.

Lambs born as percentage of ewes surviving was satisfactory in all groups being: one dose of pmsg, 94%; two doses of pmsg, 106%; controls 105%.

Free access

E. M. ROBERTS and D. G. EDGAR

Summary.

Anoestrous Romney ewes were treated for 10 or 13 days with intra-vaginal sponges containing 400 mg of progesterone or 40 mg of 6-methyl-17-acetoxyprogesterone. Pregnant mare's serum gonadotrophin (pmsg) was injected subcutaneously on the 10th and 26th, or 13th and 29th days.

A more highly synchronized pattern of oestrus occurred in ewes which retained sponges for 13 days than at 10 days. The number of ewes lambing and the number of lambs born as a percentage of ewes treated was as high as in later-lambing untreated ewes.