Preliminary Study On Breeding Techonology Of Procambarus Clarkii (Girard)

Procambarus clarkii (Cirard) belongs to Decapoda, Reptantia, Cambaridae, Procambarus. It originally distributed in the north of Mexico and the south of America, and was introduced into China by Japanese in the 1930s. Now it distributes in more than 10 provinces of China. In some areas, it has been a predominant species and one of the main aquatic animals of China. The artificial breeding of Procambarus clarkii has been hot in China nowadays due to its delicious taste and high price. The artifical reproductive technologies in Procambarus clarkii were investigated to help the farmers developing more delicious crayfish and healthy aquatic foods. The results were as follows:1. The effects of feeding vitamin E (VE) on the Procambarus clarkii were analyzed. It was showed that additional 0.02% VE in basic food might significantly improve the reproduction of Procambarus clarkii.2. The embryo and larval development of Procambarus clarkii was observed detailedly. At the water temperature of around 22-25 °C, the embryo color changed from yellow, brown to brown with dark red with the development of embryos. Around 28-35 days later, the larvae hatched out. The new-hatched larvae were stayed under the abdomen of the mother craysifishes for around one week, then they might left their mother for sometime for finding foods. The larvae preferred the meat and tiny animals (such as zooplankton) than plants.3. The effects of temperature on growth, survival and development of larvae of Procambarus clarkii were studied. The 1 or 2-month-old crayfish larvae hardly grew and developed when the water temperature was below 18℃. The growth rate of these larvae was increased with the raising of water temperature. However as high as 31℃ of water temperature caused serious mortality. Furthermore the very low temperature (0-2"C) may resulted in the death of the larvae, while the adults were more resistant to the cold water. So, we suggest that in the middle and north of China, the larvae or juveniles should be kept warmed to spent the winter.