Integrated morphophysiological assessment of two methods for sperm selection in bovine embryo production in vitro

Extensive work was done regarding the ability of Swim up and Percoll gradient to select functional sperm for in vitro embryo production (IVP) systems. The aim of this work was to compare Swim up and Percoll as methods of sperm selection by ultrastructural, biochemical and functional studies. Frozen-thawed semen from two bulls (Experiments 1 and 2, respectively) were treated using Swim up or Percoll discontinuous gradients. Motility, sperm membrane ultrastructure, sperm proteins, in vitro embryo production (insemination doses, cleavage, embryo yield and quality) and embryo sex ratio were scored and compared. Electron transmission microscopy of outer sperm membranes showed higher (P