PEDICLE AND FIRST ANTLER GROWTH IN REINDEER CALVES

Janice E. Rowell¹, John E. Blake¹, and James M. Suttie².
¹Institute of Arctic Biology, University of Alaska Fairbanks, AK 99775-7000, USA. ²Ag Research Invermay Agricultural Center, Mosgiel, NEW ZEALAND.

We monitored growth and development of reindeer antlers in 9 reindeer calves (5 males, 4 females) from birth to 1 year of age. The calves were weighed, blood sampled and the frontal lateral crest carefully palpated for pedicle initiation on the day of birth and at days 2, 4, 7, and then at weekly intervals for the remainder of the year. The developing pedicle/antler was measured and specific events recorded the week they first occurred (appearance of velvet antler, accessory tines, velvet cleaning, antler casting, regrowth). Calves were born between April 8-26, 1994. Pedicle initiation was first evident on day 4 in 2 females and occurred in all reindeer by day 7. Velvet skin first appeared at 4-6 weeks old when the pedicles were 3.5 ± 0.9 (x ± sd) cm long. Accessory tines developed in all calves with the first appearance occurring between weeks 8-14. Mean antler length (±sd) was 33.5 ± 4.2 cm and 46.7 ± 13.8 cm in females and males respectively. Mean antler growth was complete by week 18 in females and week 21 in males. Although velvet cleaning was a protracted and often incomplete event, all antlers were considered ossified and cleaned by week 27. Dates of casting and regrowth will be reported. Blood samples are being analyzed for estradiol, testosterone and IGF-1 and hormonal levels will be correlated with pedicle development, antler growth, cleaning, casting, sex and season.