Studies on the Mechanisms of the Non-specific Immunity Response of Glycans in Fish

• Main Authors: Hsieh, Meng tong, 謝孟通
• Other Authors: Way Shyan Wang
• Format: Others
• Language: zh-TW
• Published: 1996
• Online Access: http://ndltd.ncl.edu.tw/handle/19884555996966137723

碩士 === 國立中興大學 === 獸醫學系 === 84 === The aims of this investigation were to evalute the antibacterial efficiencies of five glycans; namely Barely (Bar), Krestin (Kre), M-glucan(MG), Scleroglucan (SG), and Zymosan (Zym), in fish by three different administration. By the phagocytic index assay, lysozyme assay, complement opsonization assay, and complement activation assay, the mechanisms of the non-specific immune response of five glycans in fish were studied in this study. After challenged with Edwardsiella tarda, the results revealed that the survival rates of fish treated with glycans were increased. Treated with 10 and20 mg/kg b.w. of glycans (Bar, Kre, MG, SG, and Zym) by the intraperitoneal injection, the survival rates of tilapia, Tilapia mossanbicus, and grass carp,Ctenopharyngodon idellus, bighead carp, Aristichthys nobilis, did significantlybe increased (p<0.05) but not 5 mg/kg b.w. The survival rates of fish given with 30 mg/kg b.w. of five glycans by the oral administration were significantly raised (p<0.05). However, fish received orally with 10 or 20mg/kg b.w. of five glycans were not fish immersed with 300 ppm of glycans weresignificantly increased but not 100 ppm and 200 ppm. From the lysozyme, complement opsonization assays, fish treated with glycans were able to enhance the abilities of lysozyme, and complement opsonization. The results of the lysozyme assay revealed that the lysozyme activity indexes of tilapia and eel treated with Bar, Kre, MG, SG, and Zym were (5.31,7.01), (5.14, 6.44), (6.44, 5.79), (5.79, 5.29), and (5.79, 6.76), respectively.The phagocytic indexes (PIs) of nephro phagocytes of tilapia and eel treated with Bar,Kre, MG, SG, Zym were (58.6, 61.7), (58.4, 59.2), (62.5, 61.2), (60.7,60.4), (61.9, 59.9), respecectively. In the complement opsonization assay, the results shown that the PIs of nephro phagocytes of tilapia and eel treated withBar, Kre, MG, SG,and Zym were (68.7, 69.7), (65.9, 68.4), (69.2, 70.1), (70.0,70.7), (67.9, 69.3), respectively. The results of the glycan phagocytosis of monocyte test shown that glycansincreased the monocyte percentages in fish. The phagocytic one or three glycangranule`s percentages of monocytes of tilapia treated with Bar, Kre, MG, SG, and Zym were (39.4％, 24.7％), (36.5％, 19.3％), (41.3％, 26.5％), (39.7％, 20.1％), (33.8％, 18.3％), (64.1％, 59.0％),(55.8％, 55.4％), (67.8％, 67.8％),(59.7％,56.6％), and (52.1％, 50.6％), respectively. The phagocytic one or three glycan granules percentages of monocytes of eel treated with Bar, Kre, MG, SG, and Zym were (37.1％, 21.9％), (34.8％, 20.6％), (39.4％, 28.4％), (32.9％, 23.7％), and (30.3％, 21.3％), respectively. From the classical and alternative complement activation assay, the results revealed that the glycans did active both complement passway functions.In the classical complement activation assay, the CH50 of tilapia treated withBar, Kre, MG, SG, and Zym in vitro and in vivo were (241.45, 201.87), (233.77,199.65), (251.16, 211.74), (255.12, 216.12), and (252.34, 204.29), respectively.In the alternative complement activation assay, the ACH50 of tilapia treated with Bar, Kre, MG, SG, and Zym in vitro and in vivo were (861.91, 487.12), (712.60, 599.37), (896.84, 631.58), (637.32, 493.49), (655.44, 529.63), respectively. However, the ACH50 of the classical complement activation assay of eel treated with glycans in vitro and in vivo were not ableto be detected because there were a lot of unknown factors in the eel serum to break rabbit`s RBCs. From above assays, the results of this study reveal that fish treated with glycans (Bar, Kre, MG, SG, and Zym) by any one of three kinds of minimuneffect dosage of glycans for intraperitoneal, oral, and immersion administrationare 10 mg/kg b.w., 30 mg/kg b.w., and 300 ppm, respectively. All of tested glycans are proven to stimulate the non-specific immune response in fish.