Studies on the effect of environmental factors on growth of tubificidae

The effect of environmental factors such as life styles pH and DO and temperature on the growth of tubificidae were discussed base on L. hoffmeisteri. The experimental results indicated that attached growth system is superior than suspension growth system for Tubificidae. The average growth rate was 0.466 g.g^-1 and -0.242 g.g^-1 respectively after three weeks culture. It is found that high DO concentration is benefit to Tubificidae when DO changes from 0 to 4.0mg/L. When DO is 0 ~ 0.5mg/L, the death rate is 30% approximately. Tubificidae can grow well when pH is about 7. It is sensitive to temperature, the growth rate increase from 0.338 g.g^-1 to 0.426 g.g^-1 with temperature rising between 15°C~25°C. But when the temperature is above 25°C, the growth rate decrease and its death rate is over 40%.