Electronic Theses and Dissertation

Ikan kerapu ekor bulan (Variola albimarginata) merupakan salah satu target tangkapan nelayan karena nilai ekonomis dan permintaannya yang tinggi. Tujuan dari penelitian ini yaitu menganalisis biologi reproduksi terkait hubungan panjang-berat, sebaran ukuran panjang, rasio kelamin, sebaran tingkat kematangan gonad, indeks kematangan gonad, fekunditas dan histologi gonad. Ikan sampel diperoleh dari hasil tangkapan nelayan di perairan Pulau Simeulue, Aceh lalu dianalisis di Laboratorium Genetika dan Biodiversitas Akuatik, Fakultas Kelautan dan Perikanan dan di Laboratorium Histologi, Fakultas Kedokteran Hewan, Universitas Syiah Kuala. Sampel yang dianalisis selama penelitian sebanyak 312 ekor ikan V. albimarginata. Analisis hubungan panjang berat, sebaran ukuran panjang, rasio kelamin, sebaran tingkat kematangan gonad, indeks kematangan gonad menggunakan 312 ekor, analisis ukuran pertama kali matang gonad dan fekunditas menggunakan 79 ekor dan analisis histologi gonad menggunakan 4 ekor sampel. Hasil penelitian menunjukkan panjang total ikan V. albimarginata berkisar antara 18-47 cm (rata-rata 29±5 cm). Data ini menunjukkan bahwa ikan V. albimarginata yang ditangkap di perairan Pulau Simeulue masih berukuran kecil. Pola pertumbuhan V. albimarginata adalah allometrik positif (b>3). Keseluruhan sampel berjenis kelamin betina, hal ini disebabkan ikan V. albimarginata bersifat hermafrodit protogini. Puncak pemijahan berlangsung pada bulan Juli. Nilai indeks kematangan gonad (IKG) ikan V. albimarginata berkisar antara 0,04-10,39% dengan ukuran pertama kali matang gonad 29,91 cm TL. Tingkat kematangan gonad (TKG) didominasi oleh TKG II. Ikan V. albimarginata yang ditangkap di perairan Pulau Simeulue didominasi ikan yang belum matang gonad. Fekunditas total berkisar 7.875-1.347.345 butir dengan fekunditas relatif 41-3.165 butir. Pengamatan histologi gonad dilakukan ditiap tahapan TKG. Penentuan tahapan TKG secara morfologi dapat dijelaskan secara histologi. Pengamatan gonad dibawah miskroskop dengan pembesaran 10X dan 40X. Pada TKG I ovarium sedang berkembang, TKG II mengalami pra-vitellogenik, TKG III mengalami vitellogenesis, TKG IV ovum matang dan TKG V terjadi regresi. Pada pengamatan ini tidak ditemukan adanya sel sperma dan masa transisi.

White-edged lyretail (Variola albimarginata) is one of the catch targets for fishermen because having high economy value and demand. This study aims to analyze the length-weight relationship, length distribution, sex ratio, gonad maturity distribution, gonad index, fecundity and gonad histology. The fishes were collected from catches by fishermen in Simeulue Island waters, Aceh then analyze at Genetic and Aquatic Biodiversity Laboratory, Faculty of Marine and Fisheries, Syiah Kuala University and at Histology Laboratory, Faculty Veterinary Medicine, Syiah Kuala University. Total samples have analysis the length-weight relationship, length distribution, sex ratio, gonad maturity distribution and gonad index are 312 samples. Total samples have analysis fecundity are 79 samples and analysis first gonad maturity size are 4 samples. The result showed that the total length of the V. albimarginata ranged between 18-47 cm with average 29±5 cm. This is indicate that V. albimarginata have been caught in Simeulue Island waters, Aceh still in the minimum size. The growth pattern of V. albimarginata is positive allometric (b>3). The domination of female regarding V. albimarginata are protogynous hermaphrodites. The peak spawning season of this species is predicted in July. The gonad index of V. albimarginata females ranged between 0,04-10,39% with the first gonad maturity size is 29,91 cm. The gonad maturity level dominated by phase II. The catch of V. albimarginata in Simeulue Island waters are dominated by immature fish. Total fecundity ranged between 7.875-1.347.345 eggs with relative fecundity ranged between 41-3.165 eggs. Histological observation identified all of gonad maturity phase. Observation of gonad specimen on a microscope with 10X and 40X magnifications. At the phase I of gonad maturity ovary was developing, phase II was pre-vitellogenic, phase III was vitellogenesis, phase IV ready to be fertilized and phase V was regression. This study did not find sperm and transition period.