Induction of innate immunity in fish by humus extract and its protective effect

腐殖质提取物诱导鱼类先天免疫及其保护作用

基本信息

批准号：
18580311
负责人：
KODAMA Hiroshi
金额：
$ 2.39万
依托单位：
Osaka Prefecture University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
2006
资助国家：
日本
起止时间：
2006 至 2007
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-18580311/
关键词：
innate immunity ulcer disease atypical Aeromonas salmonicida cold water disease Flavobacterium psychrophilum humic substance protective immunity 疾病予防アユ Aeromonas salmonicida コイ

项目摘要

Humic substances are formed during the decomposition of organic matter in humus, and are found in many natural environments in which organic materials and microorganisms have been present. Humus extract exhibited anti-bacterial activity against 9 species 15 strains of fish pathogens. Oral administration of humus extract to carp induced effective protection against experimental atypical Aeromonas salmonicida infection. Mortality of fish and development of skin lesions such as hemorrhages and ulcers were significantly suppressed in carp treated with 10 %, 5 % or 1 % humus extract adsorbed on dry pellets. The median surviving days was also greater in fish treated with 10% or 5% humus extract than in untreated fish. Atypical A. salmonicida was isolated from ulcerative lesions of part of dead fish, but Aeromonas hydrophila and Flavobacterium sp. were also isolated from these fish, verifying bacterial population changes during the progression of skin lesions. Oral administration of humus extract to ayu induced effective protection against experimental atypical Flavobacterium psychrophilum infection. Mortality of fish (65%) and development of skin lesions such as ulcers and hemorrhages were significantly suppressed in ayu treated with humus extract. F. psychrophilum was isolated from ulcerative lesions of part of dead fish, and bacterial DNA could be amplified using PCR in dead control fish. Surviving rate of ayu treated with humus extract was 96%, and no gross skin lesion was observed. No bacteria was isolated and no bacterial DNA was amplified in survived fish. These results clearly show that treatment of fish with humus extract is effective in preventing A. salmonicida disease and cold water disease.

腐殖质是在腐殖质中有机物分解过程中形成的，并且在存在有机材料和微生物的许多自然环境中发现。腐殖质提取物表现出对9种鱼类病原体的抗菌活性。口服腐殖质提取物以鲤鱼诱导有效的保护，以防止实验性非典型气管salmonicida感染。鱼类的死亡率和皮肤病变的发育（例如出血和溃疡）在用10％，5％或1％的腐殖质提取物治疗的鲤鱼中受到显着抑制。在用10％或5％的腐殖质提取物处理的鱼类中，生存的日子的中位数也比未经处理的鱼类更大。从一部分死鱼的溃疡性病变中分离出非典型salmonicida，但疏水性气瘤菌和黄杆菌SP。还从这些鱼类中分离出来，在皮肤病变进展过程中验证细菌种群的变化。口服腐殖质提取物对AYU诱导的有效保护，以防止非典型非典型黄杆菌感染。在用腐殖质提取物处理的AYU中，鱼类的死亡率（65％）和皮肤病变的发育受到了显着抑制。从一部分死鱼的溃疡性病变中分离出精神病。用腐殖质提取物治疗的AYU存活率为96％，没有观察到皮肤损伤。没有分离细菌，也没有在生存的鱼中扩增细菌DNA。这些结果清楚地表明，用腐殖质提取物治疗鱼可以有效预防萨尔霉菌疾病和冷水病。