Effectiveness of aglepristone at lower-than-standard doses in prevention of pregnancy in mismated bitches

Bu çalışmanın amacı, köpeklerde istenmeyen çiftleşmeler sonrası gebeliğin engellenmesi amacıyla farklı dozlarda uygulanan aglepristonun klinik etkinliğinin araştırılmasıdır. Bu amaçla, çiftleşmenin doğrulandığı 48 dişi köpek materyal olarak kullanıldı. Köpekler rastgele 4 gruba ayrılarak uygulama gruplarında, diöstrusun ilk 10 günü içerisinde 24 saat arayla 2 kez 5 mg/kg (grup I, n=12), 7.5 mg/kg (grup II, n=12) veya 10 mg/kg (grup III, n=12) dozunda aglepriston uygulandı. Oniki köpek (grup IV) kontrol grubunu oluşturdu. Gebelik muayenesi diöstrusun 30. gününde ultrasonografik yöntemle gerçekleştirildi. İlk ilaç uygulamasının 0, 3 ve 7. günleri ile ultrasonografik muayene günü alınan kan örneklerinde plazma progesteron konsantrasyonları radioimmunoassay yöntemiyle belirlendi. Grup I’de bir köpek dışında aglepriston uygulanan köpeklerin hiçbirinde gebelik belirlenmedi. Kontrol grubunda gebelik oranı %83.3 olarak belirlendi. Çalışma gruplarında ortalama plazma progesteron konsantrasyonları 0 ve 3. günlerde belirgin değişiklik göstermedi (P0,01). Aglepriston uygulaması grupların tümünde interöstrus aralığının kısalması ile sonuçlandı (grup I: 15.33±5.29 gün; grup II: 12.78±4.94 gün; grup III: 14.45±4.29 gün, P>0.05). Aglepriston uygulanan 20 adet köpek takip eden östrusta çiftleştirildi ve %90 gebelik oranı saptandı. Standarttan daha düşük dozlarda uygulanan aglepristonun istenmeyen çiftleşmeler sonrası gebeliğin engellenmesinde etkili olduğu ve uygun maliyetli bir tedavi seçeneği sunduğu sonucuna varıldı.

Anahtar Kelimeler:

ultrasonografi, dişi köpek, diöstrüs, dozaj etkileri, ilaç tedavisi, kızgınlık, farmakodinamik, farmakokinetik, gebelik, gebelik komplikasyonları, gebelik oranları, progesteron, üreme randımanı, dölverim performansı, üreme özellikleri

Köpeklerde istenmeyen çiftleşmeleri takiben gebeliğin engellenmesinde standarttan düşük dozlarda aglepristonun etkinliğinin araştırılması

The objective of this study was to evaluate the clinical efficacy of three different doses of aglepristone administered in early diestrus for prevention of pregnancy in mismated dogs. A total of 48 mismated, copulation confirmed bitches were used as material. Bitches were randomly allocated into one of four groups and treatment groups received 5 mg/kg (group I, n=12), 7.5 mg/kg (group II, n=12) or 10 mg/kg (group III, n=12) of aglepristone by two injections, 24 h apart within 10 days of diestrus. Twelve bitches (group IV) served as controls. Pregnancy was assessed by ultrasonography on day 30 of diestrus. Blood samples were collected for determination of plasma progesterone concentrations by radioimmunoassay on days 0, 3 and 7 of first aglepristone administration and on the day of ultrasonographic examination. None of aglepristone treated bitches except for one bitch in group I became pregnant. Pregnancy rate in the control group was 83.3%. There was no significant difference between mean plasma progesterone concentrations in study groups on day 0 and 3 (P>0.05). On day 30 of diestrus, plasma concentrations of progesterone were significantly lower in aglepristone treated bitches (group I: 92.60±5.74 nmol/L; group II: 85.66±3.69 nmol/L; group III: 78.87±4.86 nmol/L) compared to controls (110.62±6.24 nmol/L, P<0.01). Aglepristone administration resulted in shortening of interestrus interval in all groups (group I: 15.33±5.29 days; group II: 12.78±4.94 days and group III: 14.45±4.29 days, P>0.05). Twenty aglepristone treated bitches were bred in the subsequent estrus and overall pregnancy rate obtained was 90%. In conclusion, aglepristone at lower-than-standard doses administered in early diestrus effectively prevents pregnancy in mismated bitches and potentially offers a cost-effective treatment option.

Keywords:

ultrasonography, bitches, dioestrus, dosage effects, drug therapy, oestrus, pharmacodynamics, pharmacokinetics, pregnancy, pregnancy complications, pregnancy rate, progesterone, reproductive efficiency, reproductive performance, reproductive traits,

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