The use of cloprostenol, fenprostalen and prostaglandin F2 alpha in the superovulation of cows

THERIOGENOL.OGY THE USE OF CLOPROSTENOL,FENPROSTALEN AND PROSTAGLANDIN P2 ALPHA IN THE SUPEROVULATION OF COWS BRENT PERRY AND LLOYD DONALDSON Rio Vista International, Inc. Rt 9 Box 242 San Antonio, Texas 18227 Estrus response was measured in cows superovulated with a total of 28 or 40 mg FSH-,P(Burns Biotec, Omaha, NE) in descending divided doses over 4 days. On the third day the cows were treated with one of the following prostaglandins: cloprostenol (Estrumate, Haver-Lockhart, Shawnee, KS), fenprostalen (Synchrocept B, Syntex, Hidalgo, MEXICO), prostaglandin F2 alpha (PGF) (Lutalyse, The Upjohn Co., Kalamazoo, MI). In the first experiment 145 cows were treated with either 1 mg fenprostalen in the morning or 30 mg PGF, 10 mg morning, noon and evening. There was no significant difference in estrus response in 70 cows treated with fenprostalen (94.3%) and 75 cows treated with PGF (94.7%), (Chi squared = 0.06 P = 0.693). In a second experiment, 314 COWS were randomly allocated to treatments in groups of about 15 cows, being the group of cows scheduled for one week's work. A total of 193 cows received 500 11s of cloprostenol and 121 cows received 65 mg PGF, 35 mg in the morning and 15 mg at noon and 15 mg in the evening. There was no difference in the estrus response of 99.5% in cloprostenol and 99.2% in PGF treated cows (chi squared = 0.15 P = 0.693). The mean number of embryos collected per cow was 10.65 and 10.66 respectively (by ANOVA P = 0.985). The mean number of transferable embryos was 4.6 and 4.6 (by ANOVA P = 0.866) while the percent fertilized was 67.1% and 75% (by ANOVA P = 0.065), respectively, for cloprostenol and PGF treated cows. It was concluded that while the estrus response was the same for all prostaglandins, their effects on percent fertilized needed further study.

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JANUARY

1984 VOL. 21 NO. 1