Abstract: 271

IN VITRO EMBRYO PRODUCTION IN ADDAX (Addax nasomaculatus), AN ENDANGERED DESERT ANTELOPE.

ML Hall-Woods^{1 2} , CS Asa^{2 *}, KL Bauman^{2 *}, EW Houston² , MT Fischer² , RE Junge² , RL Krisher^{3 *}
Saint Louis University, St. Louis, MO ¹
St. Louis Zoo, St. Louis, MO ²
Purdue University, West Lafayette, IN ³

Domestic bovine embryo production techniques were evaluated in addax, an endangered desert antelope. Six sexually mature female addax were superstimulated with IM injections of 20 mg Follitropin V (Vetrepharm, Ontario, Canada) twice daily for four days while restrained in a drop floor chute. Oocytes were collected via laparotomy. Oocytes (n = 125) were cultured at 38.5°C at 5% CO₂ in air for 26-28 hrs in 500 µl of maturation medium (TCM 199 supplemented with 10% FCS, 0.01 U/ml each bFSH, and bLH, and 50 ng/ml epidermal growth factor). Addax semen was thawed and separated using a swim-up procedure. Oocytes were inseminated in 500 µl of fertilization medium (Tyrode’s albumin, lactate and pyruvate (TALP) medium supplemented with 2 µg/ml heparin, 20 µM penicillamine, 10µM hypotaurine, 1µM epinephrine and 1×10⁶ sperm/ml). After 20-22 hours, presumptive zygotes were cultured either for 168 hrs on monolayers of Buffalo rat liver (BRL) cells in 5% CO₂ in air or for 72 hours in G1 semi-defined medium followed by 96 hours in G2 semi-defined medium in 5%CO₂, 10%O₂, 85%N₂. The percentage of cleaved embryos for G1/G2 and BRL cells was 49.1% and 60.7%, respectively. The percent development of cleaved embryos to morula and blastocyst stages for G1/G2 and BRL cells was 21.7% and 8.1%, respectively. No significant differences (Wilcoxon sign rank test) were found between the two culture treatments. Morulae and blastocysts were stained with Hoechst 33342 to quantify cell numbers. Cell numbers were 54, 42, 26, 23 (morulae) and 57, 107 (blastocysts) in G1/G2 and 21 (morula) and 61, 80 (blastocysts) on BRL cells. Although no statistical difference was found between culture systems, possibly due to small sample size, these findings demonstrate that addax embryos can be cultured to a transferrable stage in vitro.

    This abstract is being presented on Monday, August 2 at 8:00 AM to 10:15 AM at CUB 2nd Floor Ballroom.