Cytogenetic analaysis of early stage buffalo embryos matured and fertilized in vitro

ABSTRACT

The in vitro fertilization technique offers the opportunity to study the karyotype of gametes and early embryos. Follicular buffalo oocytes were matured in TC-199 medium enriched with FCS, fertilized in vitro using thawed frozen buffalo semen and cultured at 38.5°C, 5% CO[2] and high humidity. Chromosome preparations were made from 232 buffalo embryos at 4 - to 8-cell stage after culturing for 48 hr in vitro. Only 74 embryos from 170 fixed embryos provided analyzable chromosome spreads. The percentage of embryos with chromosomal aberrations was 12.16%. The observed abnormal embryos were 5.41% haploid, 4.05% polyploid [2.70% triploid and 1.35% pentaploid] and 2.70 haploid/ diploid mosaicism. It is concluded that cytogenetic analysis of buffalo embryos is valuable for detection of chromosomal abnormalities which hinder the cleavage processes to reach to blastocyst stage