Effect Of The Pheromone In Molting Period On Behavior And Physiology Of Red Swamp Crayfish(Procambarus Clarkii)

This study was carried out to determine the effects of 19 kinds of pheromone(Cys,Phe,Gly,Leu,Asp,Thr,Val,Ile,Glu,Arg,Ser,Ala,3-carene,dodecanal,ecdysone,nonanal,naphthalene,decanal and 2,4-di-tert-butylphenol)during molt period of red swamp crayfish(Procambarus clarkii)crayfish on its behavior and physiology by the methods of behavior in the experimental conditions,to determine the type of pheromone(alarm pheromones and phagostimulating pheromone),and further explore the mechanism of pheromone by the methods of physiology and molecular biology in crustacean,and thus to provide a theoretical basis for reducing the mutual attack and increasing healthful aquaculture in crustaceans.The results were as follows:(1)The effects of molting pheromone on the behavior of crayfish.2,4-di-tert-butylphenol significantly reduced time spent at nozzle,and had not significant effect on the initial arm choice,choice number of each arm and time spent in each arm in female;2,4-di-tert-butylphenol significantly reduced choice number of each arm,and had not significant effect on the initial arm choice,time spent at nozzle,time spent in each arm in male.Dodecanal significantly reduced initial choice of dodecanal odor arm in female.Decanal significantly increased choice number of decanal odor arm in male and female.Cys significantly increased initial choice of Cys odor arm and choice number of Cys odor arm in female,and initial choice of Cys odor arm,time spent at nozzle and time spent in each arm in male.Leu,Glu and Thr significantly increased time spent in Leu arm,choice number of Glu odor arm and choice number of Thr odor arm in female respectively.The treatments of naphthalene,ecdysone,nonanal,phenylalanine,Ser,Gly,Ala,Asp,Val,Ile and Arg had not effect on all of behavior in male and female,respectively.(2)The effects of molting pheromone on the contents of monoamines in crayfish.Compared with the control group,content of DA decreased significantly in female and did not change in male under the 2,4-di-tert-butylphenol treatment;meanwhile,the content of 5-HT in male and female have no significant difference between control and treatment groups.Compared with the control group,the content of 5-HT in female and male significantly increased under the decanal treatment,and the content of DA in male and female had no significant difference between control and treatment groups.While compared with the control group,the contents of 5-HT and DA in male and female had no significant difference between control and treatment groups under the treatments of dodecanal,ecdysone and Cys respectively.(3)The effects of molting pheromone on the content of hormone in crayfish.Compared with the control group,the dodecanal treatment significantly increased the content of cortisol in male and female,the content of crustacean hyperglycemic hormone in female;the treatments of 2,4-di-tert-butylphenol,ecdysone,Cys and decanal had not effect on the contents of cortisol and crustacean hyperglycemic hormone in male and female respectively.(4)The effects of molting pheromone on the digestive enzyme activity of crayfish.Compared with the control group,the treatment of Cys significantly increased the activities of lipase and protease in gastrointestinal tissues and had not effect on the activities of amylase and trypsin in female,meanwhile it significantly decreased the activity of amylase and increased the activity of protease in male.the treatment of decanal significantly increased the activities of lipase and protease in female and of amylase and protease in male,and had not effects on the activities of amylase and trypsin in female and of lipase and trypsin in male;the treatments of the 2,4-di-tert-butylphenol,dodecanal and ecdysone had not effect on the the activities of lipase,amylase,protease and trypsin in male and female respectively.(5)The effects of molting pheromone on the expression of related genes in crayfish.Compared with the control group,the treatments of 2,4-di-tert-butylphenol and dodecanal significantly increased the expression of Hsp70 in female and male and the expression of Chh I in female,the treatments of the ecdysone and Cys had not effect on the expression of Hsp70 and significantly increased the expression of Chh I in female and male.The treatment of the decanal significantly increased the expression of Hsp70 in female and the expression of Chh I in male and female.In summary,2,4-di-tert-butylphenol and dodecanal may be alarm pheromones in red swamp crayfish,whereas decanal,Cys,Leu,Glu and Thr may be phagostimulating pheromone.Both of alarm and phagostimulating pheromones affect the signaling of nervous system for red swamp crayfish,then change the hormones levels of the cortisol,crustacean hyperglycemic,digestive enzyme and expressions of the Hsp70?Chh ?,and further regulate the behavior of the crayfish.