Concentración de la hormona folículoestimulante y respuesta a un protocolo de superovulación administrado por vía epidural en vacas Holstein

Abstract

The research was carried out at the Nero Farm of the University of Cuenca, the objective was to determine the plasma concentration of Follicle Stimulating Hormone (FSH) and the ovarian response when applying 200 mg of FSH, in a single dose epidurally, in cows. Holstein crossbreeds. Two routes of FSH administration were compared in a superovulation (SOV) protocol: intramuscular (T1) and epidural (T2). The FSH concentration, superovulatory response, ovulation percentage, quantity and quality of structures collected in each treatment were assessed. The FSH concentration remained high until hour 50, then the hormone decreased until reaching basal levels in both treatments. The number of follicles observed after SOV treatment was similar at T1 (15.5 ± 4.29) and T2 (15.3 ± 1.89). No significant difference will be observed in the diameter of the follicles in T1 (11.9 ± 0.49 mm) and T2 (10.8 ± 1.49 mm) p>0.05. The number of corpora lutea in T1 (2.8 ± 1.03) and T2 (7.5 ± 3.7), as well as their size (T1= 16.80 ± 0.68 mm; T2= 18.1 ± 0.99 mm) were similar (p>0.05). Likewise, a large number of follicles that did not ovulate were observed (T1= 12.8 ± 4.33; T2 = 7.50 ± 2.59); and no statistical difference was found between the number of structures (T1=1.8 ± 0.9; T2=4.8 ± 3.0) and transferable embryos collected (T1=0.5 ± 0.3; T2=3 .8 ± 2.6) at the end of the protocol. In conclusion, FSH administered epidurally maintained similar levels during the first 50 h to those observed when FHS was applied intramuscularly in a conventional protocol; However, at 52 h, the FSH concentration dropped to basal levels in T1, which were maintained until the end of the protocol.