Pengaruh Gonadotropin Releasing Hormone (GnRH) Terhadap Produktivitas, Siklus Bertelur Dan Biometri Organ Reproduksi Serta Hubungannya Dengan Konsentrasi Progesteron Serum Ayam Lokal (Gallus domesticus)

Abstract

This experiment was conducted to study the effect of Gonadotropin Releasing Hormone (GnRH) on productivity, egg laying cycle of the domestic fowl (Gallus domesticus) and its effect on serom Progesterone concentration, number of growing follicles and weight of the ovary, oviduct and biometry of the reproductve organs. Ten rna/lire female hens were used in this research. These hens were devided randomly into the GuRH and control group consisting of five hens each. The GnRH group was injected intramuscular into the pectoral muscle with 1 mL of 50pg/mI. GnRH, while the control group was injected with 1 mL of 0,9% saline for seven conseccutive days. The results showed significant (P<0,05) elevated producth;ty in the laying period (12 months) of the GnRB group from 50,601:0,75 eggs to 67,71:1:0,15 eggs as compared to that of the control group from 64,92x1,00 eggs to 40,521:0,30 eggs. GnRH injection, improved the egg laying cycle patterns as compared to the normal egg laying cycle by decreasing the lag time in a laying period (12 months) from 98,33:1:0,39 days to 68,00:0,81 days significantly (P<0,05) while the control group from 84,40:0,33 days to 71,33:0,78 days. Serom Progesterone concentration of the GnRH group (7,63; 1,93; 3,57; 2,92 ng/mL) increased and reached its peak significantly as compared to the control group (0,15; 0,01; 0,74; 0,98 ng/mL) on day 1, 2, 5 and 7 of treatment. The number of growing follicles (the number of F4, F5 follicles; F1, F2, F3 follicles weight) also increased significantly (P<0,05) in the GnRH group as compared to the control group, concomitant with the increasing ovarian and oviduct weight (p<0,05) in the GnRH group (37, 65:1, l6; 50,43:,58 g) aS compared to the control group (28,50:1,00; 31,15:1,65 g). GnRH also increased significanly (P< 0,05) the biometry of the reproductive organs. From this research it could be concluded that responsiveness of GnRH injection could increased Progesterone concentrations, resulting ill the number of follicular growth F4, F5 and ultimately Fl, F2, F3 increased egg production and repaired egg laying cycle. GnRH also increased weight of the ovaries, oviduct alld hiomelfy of the reproductive organs.