Profile of 17ß-estradiol, vitellogenin, and egg diameter during gonad maturation process of striped catfish Pangasianodon hypophthalmus
Authors: Pamungkas Wahyu , Jusadi Dedi , Junior Muhammad Zairin , Setiawati Mia , Supriyono Eddy , Imron Imron 
Published: July 2019

ABSTRACT This study was conducted to evaluate the profile of 17ß-estradiol (E2) and vitellogenin (Vtg) in plasma and egg diameter during gonad maturity process of striped catfish Pangasianodon hypophthalmus. Blood samples were collected from immature striped catfish, male and female with different stage of gonad maturity (stage I, II, III, and IV) to measure the concentrations of E2 and Vtg. Gonad maturity development of striped catfish was observed based on egg diameter. Result showed that E2 concentrations were the highest (843.65 pg/mL) on female with maturity stage III, the lowest on the male (26.34 pg/mL), and immature female fish (29.37 pg/mL). The protein band of Vtg was obtained on the plasma of the mature female (stage I, II, III and IV) with a molecular weight (MW) between 140−180 kDa, but it was not obtained on immature female dan male striped catfish. The highest concentration of Vtg was found in the plasma of the female fish with maturity stage III (87.34 mg/mL), then on the stage II (74.83 mg/mL), I (68.58 mg/mL), and IV (33.45 mg/mL). It showed that egg yolk formation occurred in the female mature. The average egg diameter was 0.107 ± 0.052 mm, 0.318 ± 0.086 mm, 0.864 ± 0.099 mm, and 1.041 ± 0.058 mm on the maturity stage I, II, III, and IV respectively. The increase of egg diameter along with development of gonad maturity stage indicated that egg development occurred due to the process of vitellogenesis and the addition of egg yolk on oocyte. Keywords : egg diameter, gonad maturity, striped catfish , 17ß–estradiol, vitellogenin ABSTRAK Penelitian dilakukan untuk mengevaluasi profil estradiol-17β (E2), vitelogenin (Vtg) dalam plasma dan diameter telur pada proses pematangan gonad ikan patin siam (Pangasianodon hypophthalmus). Sampel darah untuk pengukuran konsentrasi E2 dan Vtg plasma diperoleh dari ikan patin siam betina yang belum matang gonad, ikan jantan, ikan betina dengan tahap kematangan gonad yang berbeda (tahap I, II, III dan IV). Perkembangan kematangan gonad ikan patin siam diamati berdasarkan diameter telur. Hasil penelitian menunjukkan bahwa konsentrasi E2 tertinggi (843,65 pg/mL) pada ikan betina dengan kematangan tahap III, terendah pada ikan jantan (26,34 pg/mL), dan ikan betina tidak matang gonad (29,37 pg/mL). Pita protein Vtg pada sampel plasma diperoleh dari betina matang gonad (tahap I, II, III dan IV) dengan berat molekul antara 140-180 kDa, tetapi tidak diperoleh pada ikan patin siam betina yang belum dewasa dan jantan. Nilai konsentrasi tertinggi Vtg ditemukan dalam plasma darah ikan betina dengan tingkat kematangan III (87,34 mg/mL) kemudian pada tahap II (74,83 mg/mL), I (68,58 mg/mL) dan IV (33,45 mg/mL). Hal ini menunjukkan bahwa pada ikan betina dewasa terjadi proses pembentukan kuning telur (vitelogenesis). Rata-rata diameter telur adalah 0,107 ± 0,052 mm, 0,318 ± 0,086 mm, 0,864 ± 0,099 mm dan 1,041 ± 0,058 mm pada tingkat kematangan I, II, III dan IV secara berurutan. Peningkatan nilai diameter telur seiring dengan perkembangan tahap kematangan gonad menunjukkan bahwa perkembangan telur terjadi karena proses vitelogenesis dan penambahan bahan kuning telur pada oosit. Kata kunci : diameter telur, 17ß-estradiol, kematangan gonad, patin siam, vitelogenin