Toshi's work

Study of Recirculation Semi Intensive Seed Production (RESISP) 1208 Masatoshi FUTAGAWA/CORDUNAP September 30, 2012 The trial of RSISPC (Recirculation semi intensive seed production with copepod) was conducted from August 26 to September 26 2012. Production of phytoplankton failed due to cloudy weather and the water wasn’t circulated due to low production. The experiment terminated on 42 days culture (DC). Even so, there are some copepods and nauplii were produced. RESISP1208 Initial water was introduced through 120 µm bag-net, filled up 20 m 3 , and cultured high density T- Isochrysis (30 L) was added at 0 DC on August 16, 2012. Fertilizer, potassium nitrate (15-0-14, 3ppm) and triple superphosphate (0-14-0, 0.5 ppm) were applied until 9 DC and submersible light (400W) operated 18:00 to 7:00 until 12 DC. Water was supplied 5 % per day and increased 10 to 20 % when pH rise over 8.4 from 14 to 21 DC. Bag-net was removed on 16 DC. Average water temperature and pH at 10...

Introduction of SISPR (Semi-intensive seed production with rotifer) Masatoshi FUTAGAWA / CORDUNAP September 23, 2012 Recently, the combination of SISP (Semi Intensive Seed Production) and CERC (Continued Extensive Rotifer Culture) improve seed quality, survival and reduced cost with black rockfish (P49-55, 2009) , Pacific cod (2011) and sea bream (2011). The method (SISPR; semi intensive seed production with rotifer) shows that larva culture at harvest tank of CERC with or without enrichment rotifer. The advantages are produced strong larva, grow faster with less work activities compared to intensive method. I recommend the system consisting 2 units of Rotifer tank and Larva tank (10 kl), cylinder type (3.6 diameter, 1 m depth), sea and fresh water supply for Rotifer tanks, sea water supply for Larva tank, heating system for Rotifer tank, air stone (4 units) for both tank. Rotifer culture water is controlled to 28 ̊C and 29 psu by heater, sea and fresh water supp...

Wild copepod collection by bag-net collector Masatoshi Futagawa/CORDUNAP September 20, 2012. Copepod is ideal live feeds for finfish larvae culture. However, it is difficult to culture or maintain quantity unlike rotifer, this is why the culture is not popular. The method introduced to collecting wild copepod which is use for feeds and initial source for culture. Bag-net collector gathers copepod efficiently and easily. The system consist of bag-net (500 µm), airlifts (32 to 50 m/m PVC pipe and air supply) and light (40 W). The system is installed at water surface with floaters or hanging by lines. The height of the system that airlift suck high volume of water and copepod should not flow-out from bag-net (see below photos). It is important to collect copepod when surface is in calm condition with light during the night. Advantage of this system is easy collection and disadvantage is unstable collection quantity. Collected copepod should be fed in same day before re...

Mussel larvae production for Pacific beakfish larvae ( Oplegnathus insignis ) Masatoshi F UTAGAWA * ¹ Septiembre 17, 2012 *¹ Corporación Privada para el Desarrollo de la Universidad Arturo Prat, CORDUNAP, Iquique, Chile Mussel larva shows 50 m m approximately and swims freely. The size is ideal for primary live feeds for O. insignis larva. Mussel larvae are fed at density 50 larvae/ml with 6 hours interval from Day 3 to 10. Additionally, the larva has advantages of well nutrition and easy production. This method produces 30 million mussel larvae from a female at 30 hours after fertilization. The larvae survive until D2 and eggs settle on larva tank within 6 hours approximately. 1.    Mussel gonad shows that male has cream color and female has coffee color. 2.    Insert knife below the hinge, cut ligament and open shells. Press male gonad to release sperm and keep in bucket (A) with 10 L of ...