In this study, the probiotic, Bacillus subtilis E20, isolated from the human health food, natto, was used for
white shrimp, Litopenaeus vannamei, larvae breeding to improve the larval survival rate and development
by adding probiotic to the rearing water at (control), 108, and 109 cfu L1 salt water once every 3 days
during the 14 days of breeding experiment. Thereafter, stress tolerance and immune status of postlarvae
were evaluated. Shrimp larval development was significantly accelerated after adding the probiotic to the
larval rearing water at a level of 109 cfu L1. The survival rate of larvae was significantly higher in the
treatment with 109 cfu L1 compared to the control and the treatment with 108 cfu L1 after all larvae
had metamorphosed to postlarvae. Adding the probiotic to the shrimp larvae rearing water produced
a weak inhibition of bacterial growth by an analysis of the total bacterial count and presumptive Vibrio
count. For stress tests, no postlarvae died when they were reared in water in which the temperature was
decreased from 30 to 2 C at a rate of 0.1 C min1. Postlarvae had significantly lower cumulate mortality
in the treatments with 108 and 109 cfu L1 compared to the control when they were suddenly exposed to
fresh water and 60& salt water. A significant decrease in the cumulative mortality of postlarvae treated
with the probiotic at a level of 109 cfu L1 was recorded after the sudden transfer to 300 mg L1 nitrite-N
compared to the control and treatment with 108 cfu L1. The analysis of immune-related gene expressions
showed that the gene expression of prophenoloxidase I, prophenoloxidase II, and lysozyme of
larvae were significantly increased after being reared in probiotic-containing water at the levels of 108
and 109 cfu L1. However, no significant difference in serine proteinase or glutathione peroxidase gene
expressions was recorded in this study. It is therefore suggested that 109 cfu L1 of probiotic, B. subtilis
E20 adding to rearing water for shrimp larva breeding
In this study, the probiotic, Bacillus subtilis E20, isolated from the human health food, natto, was used forwhite shrimp, Litopenaeus vannamei, larvae breeding to improve the larval survival rate and developmentby adding probiotic to the rearing water at (control), 108, and 109 cfu L1 salt water once every 3 daysduring the 14 days of breeding experiment. Thereafter, stress tolerance and immune status of postlarvaewere evaluated. Shrimp larval development was significantly accelerated after adding the probiotic to thelarval rearing water at a level of 109 cfu L1. The survival rate of larvae was significantly higher in thetreatment with 109 cfu L1 compared to the control and the treatment with 108 cfu L1 after all larvaehad metamorphosed to postlarvae. Adding the probiotic to the shrimp larvae rearing water produceda weak inhibition of bacterial growth by an analysis of the total bacterial count and presumptive Vibriocount. For stress tests, no postlarvae died when they were reared in water in which the temperature wasdecreased from 30 to 2 C at a rate of 0.1 C min1. Postlarvae had significantly lower cumulate mortalityin the treatments with 108 and 109 cfu L1 compared to the control when they were suddenly exposed tofresh water and 60& salt water. A significant decrease in the cumulative mortality of postlarvae treatedwith the probiotic at a level of 109 cfu L1 was recorded after the sudden transfer to 300 mg L1 nitrite-Ncompared to the control and treatment with 108 cfu L1. The analysis of immune-related gene expressionsshowed that the gene expression of prophenoloxidase I, prophenoloxidase II, and lysozyme oflarvae were significantly increased after being reared in probiotic-containing water at the levels of 108and 109 cfu L1. However, no significant difference in serine proteinase or glutathione peroxidase geneexpressions was recorded in this study. It is therefore suggested that 109 cfu L1 of probiotic, B. subtilisE20 adding to rearing water for shrimp larva breeding
การแปล กรุณารอสักครู่..