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Effects of PMSG Dosage on Reproductive Performance of Farm-Raised Whitetail Deer
Increased popularity of hunting world class whitetail deer has prompted deer breeders to widely adopt reproductive technologies such as estrus synchronization and artificial insemination. A challenge for some breeders is to produce an optimal number of fawns from each doe; as such, management issues and genetic potential oftentimes warrant reduced ovulation rates. Thus, some technicians have advocated protocols where does that tend to be more prolific receive lower doses of PMSG than single fawn-producing does. Therefore, a study was designed to examine the effects of PMSG dosage on reproductive performance of farm-raised whitetail deer (Odocoileus virginianus). Over 2 years, mixed-age, farm-raised whitetail does (n = 100 total) were assigned to treatments consisting of: 1) 1.5 mL of 5000 I.U. PMSG for historically prolific does (n = 29 total) or 2) 2.0 mL of 5000 I.U. PMSG for less prolific does (n = 71 total). On October 24, 2012 and October 11, 2014, estrus was synchronized by intravaginal insertion of a CIDRTM 330 (Pfizer Animal Health, New York, NY, USA) containing 0.35 g progesterone. After 14 d, CIDRs were removed and does were injected intramuscularly with the appropriate dose of PMSG. Approximately 56 h later, each doe was artificially inseminated via laproscopy. Conception rates, number of fawns born per doe, and birth weights did not differ (P ≥ 0.39) between treatments. Frequency of multiple births tended (P = 0.07) to be higher for does receiving 1.5 vs. 2 mL of PMSG. Male and female fawns had similar (P ≥ 0.67) birth weights between treatments. A lower dose of PMSG for prolific does seemed to mitigate the average number of fawns born without an effect on conception rates; however, the number of multiple births still tended to be higher suggesting that a lower dose of PMSG may not be effective in achieving the optimal number of fawns from each doe.
Keywords: deer, reproduction, PMSG