Retention of liquid within insemination equipment using various equine frozen semen insemination methods and two semen freezing extenders

The objective of this study was to examine the effect of different insemination techniques and extenders on the volume of liquid dispensed from insemination equipment. The method of insemination has a significant effect on the volume of semen deposited into the mareʹs uterus when low volumes are used. Insemination pipettes that allow for direct deposit of straw contents into the uterus are preferred. Aspiration of semen into a pipette is preferred over aspiration into a syringe with deposition through a pipette when direct deposit is not possible. Use of a pipette with a smaller lumen and less length of contact with liquid provides better results. Contact of semen with equipment may allow for residual liquid accumulation on the luminal surfaces and a decrease in overall semen dose. Extenders with differing amounts of egg yolk did not influence volume of liquid dispensed.