The Application Of Vibrio Alginolyticus (VZ5) And Bacillus(BZ5) In Litopenaeus Vannamei Nursery

1.BZ5strains of Bacillus was used with the sugarcane bagasse and the feasibilitystudy of VZ5strains of Vibrio alginolyticus was administeredThe research set six treatments of BZ5strains of Bacillus with the sugarcanebagasse, the concentration of BZ5strains add104cfu/mL(add one times, add onetimes every day, add one times every two days) and106cfu/mL (add one times, addone times every three days, add one times every four days), add nothing was a controlgroup. Bacillus and bagasse has been observed in treatment effect on water qualityand growth of vannamei larvae.And the VZ5strains of Vibrio alginolyticus has beenset two treatments (add103cfu/mL and104cfu/mL one times every day, and they don’tadd bagasse),then observes the VZ5strains that has virulence and enhances thegrowth of larvae or not. The result of research has showed that: add104cfu/mL and106cfu/mL all have not significant difference. The NH4+-N of each treatment all havea rising trend, and the NO2--N of each one all have a trend which rising firstly then isplacid; which add106cfu/mL the total count keep a high level in the water, and itexplains the BZ5strains can grow well in the culture water; the bagasse causes theturbidity of water, and also make us separate larvae and bagasse difficultly inobserving and producing. The VZ5strains of Vibrio alginolyticus has not cause growunhealthily of the larvae, and through the grow seedings, it can discover that the Zoeaof vannamei in VZ5strains adding which grow better than other groups. 2.VZ5strains of Vibrio alginolyticus has been use in the breeding of vannameiAdd on the VZ5strains of Vibrio alginolyticus in a different frequency when theZoea of vannamei, and after Mysis with the added BZ5strains of Bacillus. Thenmeasures the water quality of breeding process, the bacterial density changes of water,as well as shrimp larvae growth and survival rate. Studies the effect of VZ5strains ofalginolyticus applied in the breeding of L.vannamei. The results showed that: theammonia concentration of three treatment groups in larvae of vannamei which addalginolyticus is0.062±0.015mg/L,0.025±0.002mg/L and0.038±0.002mg/L,significantly lower than the control group (0.21±0.012mg/L). The dry weight oflarvae are0.0463±0.0009g/tail,0.0420±0.0003g/tail,0.0407±0.0009g/tail, wassignificantly higher (0.0253±0.0003g/tail). Which treatments of adding Vibrioalginolyticus every day the survival rate of larvae is significantly higher than othergroups (P<0.05). VZ5strains of alginolyticus can effectively reduce the accumulationof ammonia in breeding water and promote the growth of shrimp larvae.3.The evaluation of VZ5strains of alginolyticus cooperate with BZ5strains ofBacillusThe different proportion of VZ5strains and BZ5strains add to the Zoea periodand Mysis period in the larvae of vannamei, and use15N isotope labeling the VZ5strains of alginolyticus before feeding. Measuring the water quality of larval rearingin each period, the amount of bacteria, larval growth index and the assimilation ofVZ5strains in the body of vannamei larvae. Studying the effect with the applicationof VZ5strains and BZ5strains in larval rearing, and analyzing the colonize of VZ5strains in shrimp larvae. The results show that: in Zoea period the concentration ofadded VZ5strains is104cfu/mL, and after Mysis use VZ5strains with BZ5strains,the survival rate of Mysis period is higher than other groups (43.46±5.51%). And ithas a lowest water nitrite. While adding only BZ5strains of Bacillus, a large declinein the value of its ammonia. The VZ5strains labeled by15N isotope that itsassimilation in the body of Mysis is proportional to survival. 4.The application of two probiotics in vannamei nursery productionSelecting BZ5strains of Bacillus and VZ5strains of alginolyticus as probioticand mix them to use in larval rearing of vannamei in different periods, then study theeffect of water quality and larval survival rate. The results show that: a mixture ofprobiotics which added to can reduce the accumulation of ammonia and nitritenitrogen in water, and significantly increase the survival rate of Zoea and Mysislarvae of shrimp. In Zoea and Mysis periods, the survival rate of larvae in theprobiotic group overtop19.54%and33.31%respectively which compare with thecontrol group. In addition, the group which water added probiotics can not observethe luminous phenomenon.