Artificial Spawning and Feeding of European Catfish, Siluris Glanis L., in Turkey

Abstract

This study focused on spawning and larval rearing of European catfish, Silirus glanis L., under hatchery conditions in Turkey. It was carried out to establish traditional production method for artificial breeding of European catfish in Turkey. The aim of this study was to introduce European catfish to aquaculture sector of Turkey. In spite of having suitable climate and water conditions in many regions, the catfish has not been farmed in Turkey. According to sexes of the brood catfish were separated as male and female in different tanks as soon as they reached to their sexual maturity when water temperature was being raised to 20 degrees C. The Carp pituitary was injected to brook stocks at the rate of 3-4 mg kg(-1) body weight. Eggs which were fertilized by drying method were loaded in Zuger jars. Larvae were fed with egg yolk, zooplankton, chironomid larvae and tubifex in polyester tanks during one week. A portion of post larvae were stocked in polyester tanks and they were fed with carp food (containing 35% protein), at a rate of 2.5%-livefish weight for 1 month. The other portion of post larvae was released to earthen ponds, fertilized with organic and inorganic fertilizers, for 1 month+2.5 months (totally 105 days). The larvae, in the earthen ponds, were fed with carp food (containing 35% protein), at a rate of 2.5%-livefish weight. At the end of the study, survival rates were found as 79.5% for incubation, 76.2% for prelarvae, 56.4-77.1% for post larvae. Survival rates in earthen ponds were calculated as 13.4% for 1 month period and 9.4% for summer season (2.5 months). Survival rate for fish fed with tubifex and carp feed in polyester tank was found as 73.1% during one month. The weights were 1.55 +/- 0.16 g for earthen pond culture and 3.6 +/- 0.08 g for polyester tank culture at the end of 1 month trial period. The growth and survival rates between earthen pond and polyester tank culture were significantly different (p<0.05). The weight was calculated as 74.2 +/- 0.26 g in the earthen pond at the end of study (after 105 days). As a result, it will be more suitable for European catfish production that is carried our in controlled tanks for I month to be transferred into earthen or wide ponds. It is better to say, this study fulfills a requirement for the favor of Turkish Aquaculture sector which is to bring in this fish to our sector.