Effects of pH on Fertilization and the Hatching Rates of Far Eastern Catfish Silurus asotus

  • Gao, Yang (Department of Aquaculture and Aquatic Science, Kunsan National University) ;
  • Kim, Sun-Gyu (Department of Aquaculture and Aquatic Science, Kunsan National University) ;
  • Lee, Jeong-Yeol (Department of Aquaculture and Aquatic Science, Kunsan National University)
  • Received : 2011.10.10
  • Accepted : 2011.11.20
  • Published : 2011.12.31


In this experiment, we examined the survival, fertilization, hatching times, and hatching rates of Far Eastern catfish Silurus asotus at pH ranging from 2 to 13 under laboratory conditions. Eggs could be fertilized at pH 3-12. In a hatching experiment, mortality was first observed at pH 13, when all fertilized eggs died within 8 min, followed by pH 2 (30 min), pH 12 (60 min), pH 3 (4 h), and pH 11 (5 h). Hatching only occurred at pH 4-10, with the highest hatching rate at pH 7 (52%) and the lowest at pH 10 (24%). Hatching rates in acid solutions were higher than in alkaline solutions, although the difference was not significant. Hatching was first observed at pH 10, beginning 27 h after fertilization and ending at the 31 h. A clear difference was observed between hatching times, ranging from 31 to 64 h and increasing in order with descending pH.


Supported by : Fisheries Science Institute of Kunsan National University


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