Use of electroejaculation to collect semen samples from wild seals

Abstract

Semen samples were obtained from 7 adult male gray seals (Halichoerus grypus) at a colony on Sable Island, Nova Scotia, Canada, using a portable electroejaculation system. Males were anesthetized with tiletamine-zolazepam. A probe was inserted in the rectum, and a progressive series of 10 to 15 stimulations (1 to 9 V, 25 to 750 mA) was applied. Males ejaculated after 15 to 29 minutes of stimulation and produced ejaculates with volumes of 4 to 17 ml that had vigorous, motile spermatozoa. Although trials were performed in winter conditions (0 to -15 C), simple storage methods (semen samples collected into plastic bags and placed in a warm pocket or an insulated cooler) kept spermatozoa motile for up to 4 hours after ejaculation. The procedure described here provides a means for collection of semen samples for genetic analyses and tests of reproductive competence in seals.