title: In vitro fertilization of water buffalo follicular oocytes and their ability to cleave in vitro.
abstract: Water buffalo (Murrah) oocytes were collected from ovaries obtained from a local slaughterhouse. They were classified according to the character of the cumulus cells under a stereomicroscope and then cultured in 25 mM Hepes buffered tissue culture medium-199 (TCM-199) supplemented with 5% estrous water buffalo serum in an atmosphere containing 5% CO2 in air at 39 degrees C. After 20 to 24 hours of in vitro maturation, the oocytes were cultured at 38.5 degrees C in TCM-199 supplemented with 1% estrous water buffalo serum and in an atmosphere containing 5% CO2 in air. Oocytes with compact and dense cumulus cells cleaved significantly further (P<0.01, 67.3%, 33/49) than those with fair, partially denuded oocytes with thin cumulus layers (27.5%, 25/91) or small remnants of cumulus cells and poor naked oocytes (3/100). A substantial variation in fertilization and developmental rates (16.0 to 43.8%) was observed among 4 different bulls. Late morulae were transferred nonsurgically into 14 buffalo recipients on Day 6 or 7 of their estrous cycle. One recipient was diagnosed to be pregnant by palpation per rectum on Day 60 and delivered a calf in October 1991.
authors.affiliation: United Graduate School of Veterinary Sciences, Yamaguchi University, Yamaguchi 753, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Suzuki
authors.forename: S K
authors.initials: SK
authors.lastname: Singla
authors.forename: J
authors.initials: J
authors.lastname: Sujata
authors.forename: M L
authors.initials: ML
authors.lastname: Madan