Studies On The Effects Of 5-HT On Growth And Development Of Neomysis Japonica And Eriocheir Sinensis

Neomysis japonica, which belongs to Mysidae,Neomysis Czerniavsky,is widely distributed in our country. Now mysis shrimp as a good model animals in environment monitoring has been widely accepted domestic and overseas. Eriocheir sinensis, called hairy crab belonging to Decapoda,Reptantia,Grapsidae,Eriocheir, is one of the pillar industries in crustacean shellfish breeding in our country. In recent years, people have always paid their attention to the efficient healthy breeding of Eriocheir sinensis.Biogenic amines as a kind of important bioactive substances, is widely distributed in crustaceans nervous system and peripheral organs. 5 - HT (5 - hydroxytryptamine), a kind of neurotransmitters deriving from amine class , plays a role in animal physiological and behavioral regulation, such as glucose metabolism, circadian rhythms, behavior, feeding and breeding,etc. This study is aimed at providing the basic theory and morphological informations for research in the mysis shrimp gonadal development ,the molting and growing of Eriocheir sinensis and the breeding physiology of crustaceans, through observing the effects of 5-HT on growth, development, reproduce, molting of Neomysis japonica Eriocheir sinensis and in vivo 5-HT level determination and 5-HT immunohistochemical positioning.We used 5-HT in Neomysis japonica and Eriocheir sinensis in different ways, exploreing the effects of 5-HT on growth, reproduction of Neomysis japonica and growth, molting of Eriocheir sinensis. Meanwhile, determined 5-HT level using enzyme immunosorbent method (Elisa) and high performance liquid chromatography (HPLC). Also positioned 5-HT distribution useing immunohistochemical method in Neomysis japonica, and studies on effects of different diets on the growth , digestive enzyme activity and haemocytes in juvenile Chinese mitten crab. The results showed that:1. Studies on the effects on growth, reproduction and antibacterial ability to Neomysis japonica1) Mysis shrimp after 5-HT short-term immersing, the survival rate reduced;body weight, body length have no significant changes; sexual maturity time significantly shortened, with low dose the effect is more apparent.2) 5-HT will prolong the time required to embryonic development, with the trend of reducing gradually while the increasing of 5-HT dosage. And have no effects on hatched larvae number, length, and maternal length.3) After 5-HT short-term immersing, caused no accumulation in mysis shrimp, and have no influence on antibacterial ability.2. Effects of 5-HT on growth and metamorphosis of juvenile Chinese mitten crab.1) 5-HT have no significant influence on growth, the time of metamorphosis and survival rate of juvenile Chinese mitten crab.2) 5-HT have no significant influence on growth of juvenile Chinese mitten crab. The time of metamorphosis is significant differences between different treatment group, the shortest is eyestalk excision group, next is low dose group ,the longest is high dose group. Survival rates and metamorphosis rates are different in each group, normal breeding group shows the highest. The 5-HT level is significant different in the treatment group of Chinese mitten crab after metamorphosis.3. The presence of 5-HT in ovary and hepatopancreas of Neomysis japonica detected by immunochemical method1) The results showed that changes on the distribution of positive 5-HT cells were observed with ovary development. All the follicule cells are stained positively at each ovary stage. As for the oocyte, both the cytoplasm and nucleus are stained positively during the early developmental stages, including Stage I, II, and III. But the positive intensity presents a negative trend with ovary development. The oocytes are stained negatively at Stage IV whereas were found weak positive in Stage V.2) The hepatopancreas cells are stained positively during each stage. Moreover, there are no significant difference of positive 5-HT in different types of hepotapancreas cells during the ovary development. In addition, the 5-HT positive intensities of oocyte were consistent with hepatopancreas cytoplasm throughout all ovary developmental stages (except Stage IV).