Abstract
Abstract. This study was designed to establish the efficacy of 30% polyvinylpyrrolidone solution (PVP; molecular weight 40, 000) as a solvent for follicle stimulating hormone (FSH) as a single intramuscular (i.m.) injection for superovulating beef cattle and to compare its efficacy in inducing superovulation with descending doses of FSH dissolved in saline. In experiment 1, 16 Japanese Black cows were randomly alloted to 2 treatment groups. Each of the 8 cows in the PVP group or saline group were given a single i.m. injection with 30 mg of FSH dissolved in either 10 ml of PVP or 10 ml of saline, respectively. In Experiment 2, the efficacy of a single FSH injection was compared between 15 Japanese Black cows and 12 heifers. In experiment 1, a larger number of ova and embryos was observed with FSH dissolved in PVP than in saline (9.8±2.4 versus 0). In experiment 2, the average number of embryos and transferable embryos in the control group (12.0±8.4 and 6.0±4.7) and experimental cows (10.4±7.6 and 5.2±2.2) were significantly higher (P<0.01) than in heifers (2.8±3.1 and 1.1±1.9).9).
