Effects of Melatonin Implants on Hormone Profile and Mating Behaviour in Rams

Öz

Objective: This study investigated the effects of melatonin implants on the mating behaviours and hormone concentrations of melatonin (MEL), GnRH and testosterone (TES) before the breeding season were investigated in Tahirova rams. Material and Methods: Six rams were used for hormone analysis. For the sexual behaviour test, six rams were mated with 69 ewes. The rams’ sexual behaviour was tested for 10 minutes.18 mg of melatonin implants were inserted into half of the rams and ewes. Three pellets were inserted into rams and one pellet for females. MEL, GnRH, and TES hormone analyses were performed by the ELISA method from the blood serum of the rams before implanting (Day 0) and 21, 42, 63, 94 and 129 days after implant. Results: Results showed that melatonin implantation significantly reduced MEL hormone concentration in Tahirova rams (P≤0.05). MEL concentration decreased to its lowest concentration on Day 63 in the treatment (T) group and differed significantly from the control (C) group (P≤0.05). While GnRH and TES hormone concentrations were similar between the groups, TES hormone concentrations in the C group differed according to the observation days (P≤0.05). Ano-genital sniffing, foreleg kicking, and tongue flicks behaviours were observed at a higher frequency in the T group than the C group (P≤0.05). While rams in group T had 64.8% mating efficiency, rams in group C had 86.9% mating efficiency (P≤0.05). Conclusion: The administration of subcutaneous melatonin implants before the breeding season in Tahirova rams, which induced a significant decrease in the MEL hormone concentration, is important in increasing sexual behaviours. Keywords: Tahirova sheep, GnRH, testosterone, negative response, sexual behaviour, mating efficiency

Anahtar Kelimeler

• Tahirova sheep
• GnRH
• testosterone
• negative response
• sexual behaviour
• mating efficiency

Koçlarda Melatonin Implantının Hormon Profili ve Asım Davranıslarına Etkisi

Öz

Amaç: Bu çalışmada Tahirova koçlarında melatonin implantlarının çiftleşme davranışları üzerindeki etkileri ve üreme sezonu öncesi melatonin (MEL), GnRH ve testosteron (TES) hormon konsantrasyonları araştırılmıştır. Materyal ve Metot: Hormon analizi için 6 baş koç kullanılmıştır. Seksüel davranış testi için 6 koç 69 koyunla çiftleştirilmiştir. Koçların seksüel davranışları 10 dk. boyunca test edilmiştir. Koç ve koyunların yarısına 18 mg melatonin implantı yerleştirilmiştir. Koçlara üç pellet, dişilere ise bir pellet yerleştirilmiştir. Koçların implantasyon öncesi (0. gün) ve implantasyon sonrası 21., 42., 63., 94. ve 129. günlerde kan serumlarından ELISA yöntemiyle MEL, GnRH ve TES hormon analizleri yapılmıştır. Bulgular: Bulgular melatonin implantasyonunun Tahirova koçlarında MEL hormon konsantrasyonunu önemli ölçüde azalttığını göstermiştir (P≤0.05). MEL konsantrasyonu, uygulama (T) grubunda 63. günde en düşük konsantrasyonuna düşmüş ve kontrol (C) grubundan önemli ölçüde farklılaşmıştır (P≤0.05). Gruplar arasında GnRH ve TES hormon konsantrasyonları benzer iken, C grubunda TES hormon konsantrasyonları gözlem günlerine göre farklılık göstermiştir (P≤0.05). Ano-genital koklama, ön ayak vurma ve dil çıkarma davranışları T grubunda C grubuna göre daha yüksek sıklıkta gözlenmiştir (P≤0.05). T grubundaki koçların aşım etkinliği %64,8 iken, C grubundaki koçların aşım etkinliği %86,9 olmuştur (P≤0,05). Sonuç: Tahirova ırkı koçlarda aşım sezonu öncesinde deri altı melatonin implantı uygulaması, MEL hormonu konsantrasyonunda önemli bir azalmaya neden olurken, seksüel davranışları da teşvik etmiştir.

Anahtar Kelimeler

• Tahirova koyunu
• GnRH
• testosteron
• negatif yanıt
• seksüel davranış
• aşım etkinliği

Kaynakça

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