Thorne, Jacob Westley (2013-05). Fertility of Beef Recipients Following a Fixed-Time Embryo Transfer Protocol that Includes Follicle Stimulating Hormone Diluted in Hyaluronan. Master's Thesis.
Thesis
This study was performed to test the viability of administering a single 40 mg dose of Folltropin-V(R) (FSH, Bioniche Animal Health) diluted in SRF (MAP-5 50, Sodium Hyaluronate, Bioniche Animal Health) on day 5 of a recipient synchronization protocol to beef cows to evaluate its effect on recipient fertility. All recipients were administered an estradiol 17beta (2.5 mg, IM) and progesterone (50 mg, IM) combination injection on day 0 and a CIDR(R) (progesterone 1.34 g, Pfizer Animal Health) was inserted. Lutalyse(R) (dinoprost tromethamine, Pfizer Animal Health, 25 mg, IM) was administered at the time of CIDR removal on day 7, and estradiol 17beta (1 mg, IM) was administered on day 8. On day 16, the presence of at least one corpus luteum (CL), detected via ultrasound, resulted in the recipient receiving an embryo (both fresh and frozen-thawed embryos were used). Embryos were not transferred into cows that did not show the presence of a CL. Dependent variables for which data were collected included circulating progesterone levels at the time of transfer, number of CLs and CL diameter, circumference, and area; measured in millimeters. The study (n=572) consisted of a treatment group (n=268) and a control group (n=304), and included both Bos indicus (Brahman influenced) crossbred (n=115) and Bos taurus (Angus based) cows (n=457). Pregnancy rates for Treated recipients (40.67%A) and Control recipients (52.96%B) differed (P<.05). There was no difference in the mean number of CLs per recipient for Treated (1.14 +/- .03) and Control (1.10 +/- .02) cows, nor was there a difference in progesterone (P4) at the time of transfer for Treated (3.14 +/- .40 ng/mL) and Control (3.23 +/- .18 ng/mL) recipients. Overall, the inclusion of Folltropin-V(R) diluted in hyaluronan in a FTET synchronization protocol did not improve the fertility of beef recipients.
