Livestock Studies 1991, Vol 31, Num, 1-2     (Pages: 042-051)

The effects of luprostiol injections at the early and late diestrus stages on injection - estrus interval and pregnancy rates in heifers and cows

Muhammet ALAN 1 ,Kenan ÇOYAN 1 ,Melih AKSOY 1 ,Tevfik TEKELİ 1 ,Kürsat IŞIK 2 ,Semra SEZEN 2

1 S. Ü. Vet. Fak. Doğum ve Reprodüksiyon Ana Bilim Dalı -KONYA
2 Hayvancılık Merkez Araştırma Enstitüsü -KONYA
3 Bayer Türk Kimya San. Ltd. Sti. -İSTANBUL
- The effects of luprostiol injections at early (5-9 th days of cycle) and late (10-15 th days of cycle for heifers and 10-14 th days for cows) diestrus on injections- estrus intervals and pregnancy rates obtained from fixed time inseminations at 72 and 96 th hours after injections were investigated on thirty - six animals (18 cows and 18 heifers).

The injection-estrus intervals for the early and late stages were 49 and 53.75 hourse in heifers (P >0.05) and 48.86 and 71.75 hours in cows (P< 0.001).

Pregnancy rates in heifers and cows injected with luprostiol at the late stage of diestrus were 75 %. However in heifers and cows following injections with luprostiol at early diestrus pragnancy rates were 30 and 50 %, respectively.

As a conclusion, Injection-estrus intervals in animals received luprostiol injections at early diestrus were shorter than those of animals received luprostiol at late diestrus.

It has been considered that fixed time inseminations at the 72 and 96 th hours after luprostiol injections arent favourable for the animals receiving ruprostiol at early diestrus and the inseminations should be held earlier than 72 th hours or following the estrus detection. Keywords :