Abstract
This study took place over a 3 year period and was conducted in 4 phases. In total, 40 mares of stock horse type were used. All mares were in good health, but had failed to conceive or did not give birth to a live foal from the preceding year's breeding. In phase one, 6 mares were separated in to 3 groups of 2 mares each. Each group received an intramuscular injection of 17-hydroxyprogesterone-n-caproate (17-OHPC), Delalutin. Group I received 125 mg; group II, 250 mg and group III, 375 mg of 17-OHPC. The results were not conclusive. In phase two, 9 mares were randomly divided in to 3 groups of 3 mares each. Group I received 20 mg; group II, 30 mg; and group III, 40 mg of 17-0HPC per 100 pounds body weight. The treatment groups did not differ significantly in number of days in estrus, number of days from ovulation to the next 3 cm follicle, number of days from a 3 cm follicle to ovulation, or conception rate. When the data accumulated from the treated groups were compared to similar data recorded from normal mares a significant difference (P <0.05) was calculated for the number of days from ovulation to the next 3 cm follicle, with the mean time being 7 days less for the treated mare is. In phase three, 15 mares were randomly divided in to 3 groups of 5 mares each. Group I received 40 mg of 17-OHPC per 100 pounds body weight, group II received 20 mg of 17-OHPC per 100 pounds body weight, and group III was designated as the control. There were no significant differences between groups for number of days in estrus. ...
McCall, James Paul (1972). Progesterone treatment of anovulatory mares. Texas A&M University. Texas A&M University. Libraries. Available electronically from
https : / /hdl .handle .net /1969 .1 /DISSERTATIONS -185332.