Fertility and twinning in Canadian reindeer

• Published in: Rangifer
• Main Author: G. F. Godkin
• Format: Article in Journal/Newspaper
• Language: English
• Published: Septentrio Academic Publishing 1986
• Subjects: reindeer; pregnancy rates; twinning; Canada; fawn survival; recruitment; Animal culture; SF1-1100; Northwest Territories; Mackenzie Delta; Tuktoyaktuk; Slaughter; Rangifer; Rangifer tarandus
• Online Access: https://doi.org/10.7557/2.6.2.639; https://doaj.org/article/56cd9dfcf532477ebb52970a2efd9bd8

This study was carried out from 1976 to 1981 on the Mackenzie Delta reindeer herd with the co-operation of the owners, Canadian Reindeer Ltd., Tuktoyaktuk, Northwest Territories. The reproductive organs of 4050 female reindeer (Rangifer tarandus) were collected at slaughter. The pregnancy rates averaged 99.5% of the females examined. In the years 1978 and 1981, 24.7% (713) of the animals were carrying twins, as compared to a twinning rate of 0.4%) observed for the intervening years. Nineteen animals were not pregnant. Of these, 14 were emaciated with no gross pathology* of the reproductive tract. Five females had either a mummified fetus or uterine adhesions preventing a viable pregnancy. Estimated fawn survival rates from birth to June varied from 51.7 to 95.7%. Fawn survival from June to yearlings of June the next year varied from 51 to 86.4% as determined by count at roundup. Increment averaged 15.8% per year after a slaughter of 13.4% of the herd yearly.