The evaluation of two closes of prostaglandin F_2αanalogue, Prosolvin, for oestrous synchronisation of Syrian Awassi ewes

Abstract

An assessment was made of the effectiveness of two doses of Prosolvin, a synthetic prostaglandin F2 a , on oestrous synchronisation in local ewes during the breeding season. Thirty cycling Awassi ewes were divided equally into three groups. Ewes in group T10 and group T15 were injected intramuscularly twice with either 10 tng (T10) or 15 mg (T15) of Prosolvin, with an interval of 11 days. The third group received no treatment and served as a control group (C). Oestrus commenced in the ewes in group T10 at 83.3±42.9 hours, and in the ewes in the T15 group at 136.5 ± 109.9 hours, after the second injection of Prosolvin. In the control group (C), oestrus behaviour was more variable and commenced 251.2 ± 130.9 hours after introduction of the rams. In the time to onset of oestrus, the difference between the effects of the two doses was not significant (P > 0.05) but there was a significant difference (P < 0.05) between treated and untreated ewes. The mean serum progesterone level dropped sharply within 24 hours after the treatment, from 8.48 nmol I -1 to 0.52 nmol 1 -1 in the ewes in group T10, and from 7.95 nmol I -1 to 0.45 nmol I -1 in the group T15. The treatment had no effect on either the duration of pregnancy or birth weight. It could be concluded that it is possible to use the synthetic prostaglandin Prosolvin at doses of 10 or 15 mg for oestrous synchronisation in local Awassi ewes during the breeding season.

Ovarian status in fat-tailed Syrian Awassi ewes during different reproductive stages and hormonal treatments monitored by laparoscopy and progesterone concentrations

“…Laparoscopic examination was performed to assess the ovaries and the status of the ovarian response to the hormonal treatments inside and outside the breeding season. This reported work has helped to elucidate some other reproductive parameters in Syrian Awassi ewes as a continuation to previous studies (Zarkawi et al 1999;Zarkawi 2000Zarkawi , 2004.…”

Productive Characteristics and Reproductive Responses to Estrus Synchronization and Flushing in Abou-Delik Ewes Grazing in Arid Rangelands in Halaieb - Shalateen - Abouramad Triangle of Egypt.

“…As well Safranski et al (1992) reported that pregnancy period in control ewes and ewes treated with melengestrol acetate + PG-600 was 163.8 and 157.2 days, respectively. In contrast, Zarkawi (2000) reported that the treatment had no effect on the duration of pregnancy, which averaged 150.3 days in control and 150.4, and 150.8 days in synchronized groups with 10mg and 15mg PGF 2 α, respectively. This difference can be likely due to the different breed of sheep and the environment.…”

Hormonal treatments and the ram effect on synchronised oestrus in Awassi ewes at the beginning of the breeding season

“…Administration of exogenous prostaglandin F 2α (PGF 2α ) during the breeding season induces regression of the corpus luteum (CL), reduces progesterone concentrations, and allows for a new follicular wave to start within 2-3 days (Boland et al 1978). Responses to PGF 2α can be improved by preceding treatment with a 5-day progesterone pessary or gonadotropin releasing hormone (GnRH) or two injections of PGF 2α 11 days apart (Beck et al 1996;Zarkawi 2000;Godfrey et al 2001). However, the 5-day GnRH-PGF 2α programme alone is not effective in oestrus induction of Awassi ewes outside the normal breeding season without progesterone pretreatment (Husein & Kridli 2003).…”