Videoendoscopic evaluation of the mare’s uterus: I. Findings in normal fertile mares.

The research article presents the utilization of videoendoscopes for studying the uteri of healthy, fertile mares. These horses are from the Welsh Pony and Thoroughbred breeds, and their uterine changes across different ovarian and annual breeding cycles have been recorded.

Usage of Videoendoscopes

• The study brings up how a new generation of videoendoscopes is being utilized in veterinary research, particularly gynaecology in this case.
• The videoendoscopes utilize an electronic system for transmitting images, as opposed to the traditional optical system used by fibre-optic endoscopes. This results in a better quality image, improved handling robustness and the ability to display the image directly on a TV monitor, allowing several individuals to see the image at the same time.

Hysteroscopy of Mares

• The researchers carried out hysteroscopy, which is a procedure that allows viewing of the uterus and cervix, on fourteen Welsh Pony and Thoroughbred mares. The mares were at different stages in their annual and ovarian breeding cycles.

Observations during Oestrus and Dioestrus

• The cervix during oestrus (the reproductive phase where the mare is in heat and thus capable of conceiving) was found to be oedematous (swollen due to excess fluid) and it was lying on the vagina’s floor offering clear visibility.
• During the dioestrus phase (where the mare is not receptive to mating), the cervix appears tight and pale and is located in the centre of the vaginal fornix.
• The difference in endometrial thickness between oestrus and dioestrus is due to the variation in interstitial fluid. In dioestrus, the reduced fluid volume lets the blood vessels under the endometrium become visible. Irrespective of the phase, the endometrium surface retained a shiny quality because of gland secretions.

Other Observations and Procedures

• The flexible polythene cannula was introduced to the uterine lumen through the endoscope’s working channel to collect uterine fluid for cytological and bacteriological tests.
• Biopsies of the endometrium were also taken either with flexible forceps through the endoscope’s working channel, or with rigid forceps through the cervix alongside the endoscope. Both techniques offered precise visual selection of the sampling area. The rigid forceps were more preferred as they collected larger endometrium samples.