Jessie (Lyne) Schulteis, D.V.M.
Education: Bachelor of Science in animal sciences and industry (May 2017)
Doctor of Veterinary Medicine from Kansas State University
McNair Project: Effects of Prostaglandin Fα Injection at Breeding on Conception Rates of Beef Heifers Subject to Fixed-Time Artificial Insemination (2014)
Mentor: K.C. Olson, Ph.D.
The objective of this study was to determine if an injection of exogenous PGF2α at the time of artificial insemination (AI) increased pregnancy rate of beef heifers compared with heifers that did not receive an injection of PGF2α at the time of artificial insemination. A fixed-timed AI protocol (7-day Co-Synch + Controlled intravaginal drug release; CIDR) was used to synchronize beef heifers (n = 97; initial BW= 631 ± 58 lbs) originating from the Kansas State University Commercial Cow-Calf Unit in Manhattan, KS. Heifers were stratified by hide color, age, BW, and reproductive-tract score and assigned randomly to either a GnRH or GnRH + PGF2α injection at the time of AI. Fifty-four h after CIDR removal, heifers were exposed for timed AI; 2 fertile bulls were released with the heifers 48 h after AI. The bulls were removed 41 d after natural service exposure began. Heifers were examined for pregnancy by transrectal ultrasonography 43 d after timed AI. Conception to AI (41%) was similar (P = 0.47) between treatments; moreover, timed-AI + first natural service pregnancy rates (60%) did not differ (P = 0.90). Under the conditions of our study, injection of exogenous PGF2α did not influence pregnancy to timed AI or first natural service.