Effect of subsequent two short-term, short-term, and long-term progestagen treatments on fertility of Awassi ewes out of the breeding season

Abstract

Summary:The aim of this study was to evaluate the effectiveness of different treatment methods of progestagen with PMSG in Awassi ewes out of the breeding season. A total of 48 ewes were divided into four groups equally. In Group I, vaginal sponges (30 mg fluorogestone acetate; FGA) were administered to ewes for seven days; afterwards vaginal sponge removal at the end of 7 th days and new vaginal sponge replaced for seven days in the same group. Vaginal sponges were administered for 7 days and 14 days in Group II and Group III, respectively. Group IV (Control) served as control group. In all experimental groups, 500 IU PMSG was given at sponge removal. Parameters such as estrus response rate, pregnancy and lambing rates, interval from sponge withdrawal to onset of estrus, duration of estrus and fecundity were evaluated. There were no significant differences in terms of estrus response rate, pregnancy rate, lambing rate, and fecundity between the Group I, II and III (p>0.05). In addition to this, any difference in the duration of estrus was not observed in all groups. However, variations in the interval from sponge removal to estrus was found significant (p<0.05) differences between Group II (53±3.37 h) and Group III (41.5±1.81 h). A slight increase in progesterone levels was observed after ram introduction, but a significant decrease in progesterone levels was found after two weeks from ram introduction (p<0.05). It was concluded that there was no advantage of using two subsequent sponge treatments for achieving high progesterone concentration during treatment. In addition, short-term sponge treatment (7d) was found as effective as long-term sponge treatment in Awassi ewes out of the breeding season.Key words: Anestrus, awassi, estrus response, ewe, progestagen Ardışık iki kısa süreli, kısa süreli ve uzun süreli progestagen uygulamasının üreme mevsimi dışındaki İvesi koyunlarının dölverimine etkisi Özet: Bu çalışmanın amacı, üreme mevsimi dışında İvesi koyunlarında PMSG ile birlikte farklı progestagen uygulamalarının etkinliğini araştırmaktı. Toplam 48 baş koyun 4 eşit gruba bölündü. Grup I, vaginal süngerler (30 mg FGA) koyunlara 7 gün süreyle uygulandı, daha sonra 7. günde çıkarılan süngerin yerine yeni sünger tekrar 7 gün süreyle yerleştirildi. Grup II ve Grup III'de vaginal süngerler sırasıyla 7 ve 14 gün uygulandı. Grup IV, kontrol grubunu oluşturdu. Çalışma gruplarının tümünde süngerlerin çıkarıldığı anda 500 IU PMSG yapıldı. Östrusa gelme oranı, gebelik ve kuzulama oranları, süngerin çıkarılmasından sonra östrusa gelme aralığı ve östrus süresi ile verimlilik gibi parametreler değerlendirildi. Östrusa gelme, gebelik ve kuzulama oranları ile doğurganlık açısından Grup I, II ve III arasında önemli bir farklılık bulunmadı. Buna ilaveten, tüm gruplarda östrus süresi istatistiksel açıdan farklı olmadı. Ancak, süngerlerin çıkarılmasından sonra östrusa gelme süreleri açısından Grup II (53±3,37 saat) ve Grup III (41,5±1.81 saat) arasında önemli farklılıklar bulundu (p<0.05). Koç katımından sonra progesteron (P4) s...

Evaluating estrus synchronization and early pregnancy detection in Ossimi sheep: The influence of fluorogestone acetate treatment duration and dosage

“…Short-term synchronization is preferable to long-term synchronization in terms of pregnancy, lambing, and prolificacy ( Menchaca et al, 2017 ). This could be because prolonged progesterone therapy interferes with oocyte development by raising sub-luteal progesterone levels and increasing the frequency of LH pulses without causing an LH surge, which inhibits the biggest follicle from ovulating ( Özyurtlu et al, 2011 ) and causes older oocytes to ovulate ( Viñoles et al, 2001 ). On the other hand, short-term progestagen protocols are linked to a decreased incidence of vaginitis, whereas employing intravaginal sponges for long periods was also linked to the presence of purulent and fetid vaginal discharges upon their removal ( Vasconcelos et al, 2016 ), Long-term use of intravaginal sponges for sheep estrus synchronization, particularly for 12–14 days, is linked to negative outcomes such as vaginitis and purulent discharge.…”