Field experiments with frozen-thawed bovine embryos in Brown-Swiss heifers
2 Selçuk Üniversitesi Veteriner Fakültesi, Konya
3 Hayvancılık Merkez Araştırma Enstitüsü, Konya
4 Granada Limited Company , USA - Seven days old frozen Brangus embryos imported from Granada Limited Company of USA were non-sungically transfered to the 64 Brown-Swiss heifers.
Recipient heifers were synchronisied by two prostaglandin injections 11 days apart. Transfers were performed 7 days after the estrous. Results were controlled by rectal palpation 45 days later.
Estrous symptoms were observed between 36-72 nd hours following 2 nd prostaglandin injections (aprox. 60.47 ± 9.73 hour). After thawing, embryos were classified as, 43 morula, 9 early blastocyst, 11 blastocyst and 1 expanded blastocyst. On quality examination, excellent (Gl), good (G2) and fair (G3) embryos were differentiated 28.31 and 5 respectively. Pregnancy rate was 32.81 % after all transfers. This rate was 39.28 % in G1 and 25.80 % in G2 embryos. The highest pregnancy rate was held by using blastocyst phase embryos (62.50 %).
It's decided that, the pregnancy rates could be improved by using excellent quality and early phase embryos.
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