Document Type

Dissertation - Open Access

Award Date


Degree Name

Doctor of Philosophy (PhD)

Department / School

Animal Science

First Advisor

A.L. Slyter


The effects of flumethasone and prostaglandin F2 (PGF) on the time of parturition were studied in the ewe. Pregnant ewes with known conception dates were allotted into a 3 x 3 x 2 factorial designed experiment (1973 study) and into a completely random designed experiment (1974 study). In the 1973 study treatments consisted of three hormones (flumethasone, PGF and saline control), three levels (low, .5 mg flumethasone, 5 mg PGF, 1 cc saline; medium, 1.0 mg flumethasone, 10 mg PGF, 2 cc saline; high, 1.5 mg flumethasone, 15 mg PGF, 3 cc saline) and two routes of administration (IM and IV) with nine ewes per treatment. Treatments in the 1974 study were 2 mg flumethasone, 15 mg PGF and 4 cc saline. There were 39 ewes per treatment. All treatments in the 1974 study were administered on day 141 of gestation and a ewe was considered to have been successfully induced if she lambed within 72 hours post-treatment. In the 1973 study 78% of the ewes treated at the medium level with PGF by the IM route of administration were induced with a mean interval of 32.79 ± 8.22 hours. Flumethasone treatment at the high level by either IM or IV administration also resulted in 78% of ewes lambing within 72 hours of treatment with a mean interval of 42.00 ± 3.12 and 42.93 ± 6.71 hours, respectively. In the 1974 study 89% of the ewes given flumethasone were induced with an average response interval of 50.9 ± 2.3 hours. Thirty-three percent of the PGF-treated ewes were induced with a mean response interval of 41.7 ± 5.9 hours. Only 7.7% of the saline control ewes lambed within the 72-hour period following injection. The mean interval from treatment to parturition (all ewes included) was significantly reduced by both flumethasone (P<.01) and PGF (P<.05) treatments when compared to that for control ewes. Initial total progestins (day 141 of gestation) of control ewes averaged 7.86 ng/ml, while initial mean progestin level for flumethasone-treated ewes was 7.08 ng/ml. PGF-treated ewes initial progestin levels averaged 8.63 ng/ml. Final (within 24 hours of parturition) mean progestin levels of control, flumethasone-and PGF-treated ewes were 2.97, 3.11 and 4.16 ng/ml, respectively. Least squares analysis of variance indicated no significant differences between treatment groups in initial or final progestin levels. Initial total estrogen levels of control ewes averaged 145.01 pg/ml. Initial mean level of estrogen for flumethasone-treated ewes was 167.83 pg/ml. PGF-treated ewes averaged 137.83 pg/ml. Final estrogen levels were 250.34, 279.22 and 244.49 pg/ml for control, flumethasone- and PGF-treated ewes, respectively. There was no statistical difference indicated by least squares analysis of variance between treatment groups in either initial or final estrogen levels.

Library of Congress Subject Headings

Sheep -- Breeding




South Dakota State University