Culture of Emperor Snapper Lutjanus Sebae

Emperor snapper Lutjanus sebae is one of marine fishery commodities with high economic value, therefore capture rate of this fish is very high. To maintain its sustainability in nature, the culture of this species should be done in proper manner to support their conservation. This study was aimed to determine the culture technology of emperor snapper L. sebae. The eggs for this study was taken from wild broodstocks that have been domesticated in concrete rearing tank. Larval rearing was done in 500 liter polyethylene tank placed in hatchery. Phytoplankton Nannochloropsis oculata was used during larval rearing period. Larvae was fed with zooplanktons such as rotifer Brachionus rotundiformis and copepod Tisbe holothuriae in the beginning of rearing and artemia starting in day 16. Observed parameters were absorption of endogenous energy, preferrence of food, larval growth and survival rate. The result indicated that total length of newly hatched larvae were 2,44-2,63 mm, while yolk sac and oil globule were 179x10-3 - 183 x10-3 mm3 and 0,66x10-3 - 0,67x10-3 mm3, respectively. Yolk sac was absorbed at 60 hours after hatching, while oil globule almost totally absorbed at 80 hours after hatching. Live food rotifers were dominantly preferred by larvae until 10 days old, while copepods and artemia were preferred after 12 and 16 days. Larval rearing period was 22-29 days at water temperature 28.5-30.0°C. Survival rate of larvae were between 1.5 until 2.1%, while juveniles were 84.00-100.00%

Pengaruh Perbedaan Waktu Awal Pemberian Pakan Buatan Terhadap Pertumbuhan Dan Aktivitas Enzim Pencernaan Larva Ikan Kerapu Bebek Cromileptes Altivelis (Valenciennes 1828)

The effect of different initial time of artificial feeding to the growth and the activities of digestive enzymes of humpback grouper larvae Cromileptes altivelis (Valenciennes 1828).Humpback grouper is an economically marine finfish commodity, so it is important to scale up its culture. In aquaculture, feed is dominantly affecting to fish growth. Besides live feeds, theartificial feed is also given to fulfill the need of nutrient for larvae. However, the capability of larvae to digest the artificial feed is still limited because of its simplicity and immaturity of digestive system structure. Digestive enzymes are a biological indicator to figure out the capability of larvae to digest the artificial feed. This research was conducted to find out the influence of different initial time of artificial feeding to the growth and digestive enzyme activity of humpback grouper larvae. Larvae rearing were done in hatchery. Larvae were fed with live feed rotifers started in the evening of the second day. The treatment given in this research was the difference initial time of artificial feeding, i.e: (A) given at 8 days old larvae and (B) given at13 days old larvae. The variable observations were the growth and digestive enzyme activity of larvae. The results indicate that the different initial time of artificial feeding influenced to thegrowth and digestive enzyme activity of humpback grouper larvae. Total length, body weight, length of dorsal spine and ventral spine of 30 days old humpback grouper larvae on treatment A were 17.47±2.35 mm, 0.11±0.04 g, 6.83±0.45 mm and 5.07±0.50 mm, respectively, while on treatment B were 13.23±2.53 mm, 0.04±0.02 g, 5.73±1.11 mm and 4.48±0.50 mm, respectively. Up to 30 days old larvae, protease and amylase enzymes activities of larvae on treatment A was higher than on treatment B, while lipase enzymes activity of larvae on treatment B was higher than on treatment A. Therefore, the different initial time of artificial feeding gives the different effect on the growth and the activities of protease, amylase and lipase enzymes of humpback grouper larvae

Pertumbuhan Larva Dan Produksi Benih Ikan Kerapu Bebek Cromileptes Altivelis Valenciennes, 1828 Hasil Budidaya Turunan Ke-3

Ketersediaan induk dalam suatu USAha pembenihan memiliki peran yang sangat penting. Namun demikian, ketersediaan induk yang berasal dari alam sangat terbatas jumlahnya, sehingga perlu dilakukan penyediaan calon induk yang berasal dari hasil budidaya. Ikan kerapu bebek Cromileptes altivelis Valenciennes, 1828 turunan pertama (F-1) dan turunan kedua (F-2) sudah dapat diproduksi dari hasil budidaya, namun benih turunan ketiga (F-3) belum dapat diperoleh. Penelitian ini bertujuan untuk mendapatkan karakteristik morfologis dan pertumbuhan larva ikan kerapu bebek F-3 sebagai calon induk F-3, serta tingkat keberhasilan produksi benihnya. Pemeliharaan larva dilakukan dalam hatchery hingga larva menjadi benih. Parameter yang diamati meliputi panjang total dan panjang duri sirip larva, berat tubuh larva serta sintasan dan jumlah produksi benih. Hasil penelitian menunjukkan bahwa panjang total larva umur 5, 15, 25 dan 35 hari, masing-masing adalah 3,20±0,07; 4,42±1,11; 8,35±1,12 dan 12,51±3,23 mm. Duri sirip mulai terukur pada larva umur 15 hari. Berat larva umur 30 hari adalah 0,11±0,04 g. Pola pertumbuhan panjang total dan berat tubuh larva adalah eksponensial, sedangkan pola pertumbuhan duri siripnya adalah linier. Masa pemeliharaan larva hingga menjadi benih adalah ± 40 hari. Jumlah benih ikan kerapu bebek F-3 yang diproduksi dalam satu kali siklus pemeliharaan berkisar 440 hingga 2.300 ekor dari 50 ekor induk dan 3 kali siklus pemijahan dengan tingkat kelangsungan hidup 1,30% hingga 8,80%. Hasil penelitian ini mengindikasikan bahwa ikan kerapu bebek F-3 dapat diproduksi dari hasil budidaya seperti halnya pada F-1 dan F-2