Superovulation of beef cattle with a split-single intramuscular administration of Folltropin-V in two concentrations of hyaluronan

Three experiments were designed to evaluate the superovulatory response of beef cows following two intramuscular (IM) administrations 48 h apart of Folltropin-V diluted in reduced concentrations of hyaluronan (Split-single IM administrations; Experiment 1—300 mg Folltropin-V on the first day and 100 mg 48 h later; Experiment 2—200 mg Folltropin-V on the first day and 100 mg 48 h later). In Experiments 1 and 2, superovulatory response and ova embryo/embryo production did not differ between donors receiving twice daily IM of Folltropin-V over 4 days and those given a Split-single IM administration of Folltropin-V diluted in 10 mg/mL hyaluronan solution. Experiment 3 compared Split-single IM administration of Folltropin-V diluted in two hyaluronan concentrations (5 or 10 mg/mL) with Folltropin-V diluted in saline and administered twice-daily over 4 days. Beef cows (17 Angus and 12 Simmental) were randomly assigned to one of three treatment groups to be superstimulated three times in a cross-over design, so that all cows received all treatments. A total dose of 300 mg Folltropin-V was divided into twice-daily IM over 4 days, or in two IM treatment 48 h apart (200 mg on first day and 100 mg 48 h later) in the hyaluronan groups. Mean (± SEM) numbers of transferable embryos did not differ among treatment groups (Control: 4.0 ± 0.8; 10 mg/mL hylauronan: 5.0 ± 0.9; 5 mg/mL hyaluronan: 6.1 ± 1.3). We concluded that the Split-single IM administration of Folltropin-V diluted in either concentration of hyaluronan resulted in a comparable superovulatory response to the traditional twice-daily protocol.