Limitations of intrauterine balloon catheters for ova collection in sheep

Abstract

Attempts were made to collect ova from superovulated ewes by surgically fitting a balloon catheter in each uterine lumen either during the luteal phase or follicular phase of their oestrous cycle. A total of six ovulations and 37 unovulated follicles were observed and one unfertilized, degenerating ovum was collected from the six catheterised ewes. This was significantly different (P < 0.01) from the 22 ovulations and eight unovulated follicles observed and the 14 ova recovered from the three control ewes. The presence of catheters prevented plasma LH peak during the oestrus following catheterisation, and as a result, ovulation failed as evidenced by the low plasma progesterone levels from that oestrus throughout the experiment. No pathogenic micro-organisms were isolated from the uteri of any of the ewes. However, histological studies showed infiltration of lymphocytes and monocytes in the endometrium of the catheterised ewes but not in the controls, indicating an immunological type of reaction to the presence of the catheters.