| Summary: | 碩士 === 國立臺灣海洋大學 === 水產養殖學系 === 107 === This study aim to develop the probiotic application in shrimp aquaculture by investigating the effects of Lactobacillus reuteri and Lactobacillus sp. on the growth performance and non-specific immune responses of white shrimp (Litopenaeus vannamei).
Two lactic acid bacteria strains were sprayed on the feed at the effective concentrations of 103, 105 and 107 cfu/g. Experimental groups were referred as Lr3, Lr5, Lr7 and Ls3, Ls5, Ls7. During the 8 weeks feeding experiment, dietary supplement with Lactobacillus showed no negative effect on the water qualities, including ammonia-nitrogen, nitrite-nitrogen and Vibrio sp. count. Moreover, the concentrations of Lactobacillus in aquatic water were detected in the range of 1.33±0.58×101 to 9.77±1.34×102 cfu/mL.
In viewing of the growth performance after 8 weeks feeding, it was shown that both strains could benefit the growth of L. vannamei. The greatest improvements in growth performances were observed in group Lr7, which has the best weight gain (107.99±3.92 %), specific growth rate (1.93±0.07 %), feed conversion rate (3.34±0.05) and survival rate (97.22±4.81 %).
In viewing of the non-specific immune responses during 4 weeks feeding, the significant increases of THC (total haemocyte count) were found in group Lr5, Lr7, Ls3 and Ls5 at 4th day; the improvement of PO (phenoloxidase activity) and O2- (superoxide anion production ratio) were observed in group Lr and Ls after 1st day and 4th day. The most significant improvement in group Lr7 could last until 28th day; The significant increases of PR (phagocytic rate) were shown in group Lr5 and Lr7 after 7th day; The PI (phagocytic index) of Lr and Ls groups increased significantly after 4th day and 14th day, respectively. The increase of PI in group Lr7 was the most significant.
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