Mina Ahangarzadeh; Masoud Ghorbanpour Najafabadi; Rahim Peyghan; Hossein Houshmand; Mostafa Sharif Rohani; Mehdi Soltani
Volume 13, Issue 1 , March 2022, , Pages 55-60
Abstract
Aeromonas hydrophila is a bacterium associated with many diseases and disorders such as fin rot, skin ulcers and lethal hemorrhagic septicemia in fish. It bears several virulence factors including type III secretion system (T3SS), aerolysin, cytolytic enterotoxin and enzymes (e.g. hemolysins, lipase) ...
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Aeromonas hydrophila is a bacterium associated with many diseases and disorders such as fin rot, skin ulcers and lethal hemorrhagic septicemia in fish. It bears several virulence factors including type III secretion system (T3SS), aerolysin, cytolytic enterotoxin and enzymes (e.g. hemolysins, lipase) that seem to play an important role in its pathogenesis. Detection of virulence markers by polymerase chain reaction (PCR) is a key procedure in defining the pathogenic ability of pathogenic bacteria and preparing a vaccine for its treatment. In this sense, this study was aimed to determine the frequency of virulence genes in isolates obtained from infected cultured carps in Khuzestan province. Out of 200 moribund carps with septicemic symptoms, 125 isolates were belonged to the motile aeromonads and 59 isolates were identified as A. hydrophila by biochemical methods. Finally, using PCR analysis, 31 isolates were identified as A. hydrophila. Five virulence genes were detected in these isolates including hemolysin, aerolysin, cytolytic enterotoxin and T3SS (aopB and ascV) by specific primers. Results showed that 23 (74.19%), 18 (58.06%), 16 (51.61%), 13 (41.63%) and 10 (32.25%) isolates possessed cytolytic enterotoxin, hemolysin, aerolysin, and T3SS genes, respectively. The results of the present study showed that among 31 isolates, only five isolates had all of dominant virulence genes. Thirteen other isolates had genotypes including hlyA+, aerA+, and act+. The remaining isolates had at least one virulence gene. This study showed that determination of the virulence genes by PCR can be a reliable method to identify a potential pathogenic Aeromonad strain.
Fish & Aquatic
Mahdi Banaee; Vahid Soleimany; Behzad Nematdoost Haghi
Volume 8, Issue 2 , June 2017, , Pages 145-153
Abstract
This study evaluated preclinical and clinical safety of marshmallow (Althaea officinalis L.) extract as a naturopathic medicine in common carp deliberately infected with Aeromonas hydrophila. The fish were fed 0 (control), 2.50, 5.00 and 10.00 g of marshmallow extract for 60 days in a preclinical experiment ...
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This study evaluated preclinical and clinical safety of marshmallow (Althaea officinalis L.) extract as a naturopathic medicine in common carp deliberately infected with Aeromonas hydrophila. The fish were fed 0 (control), 2.50, 5.00 and 10.00 g of marshmallow extract for 60 days in a preclinical experiment and then, challenged with A. hydrophila for a 10-day experiment. Significant increases were observed in aspartate aminotransferase (AST), lactate dehydrogenase (LDH), alkaline phosphatase (ALP), creatine phosphokinase (CPK) activities and plasma creatinine levels in fish fed 10 g marshmallow extract per kg feed. However, alanine aminotransferase (ALT) significantly decreased on day 60. The fish fed 2.50 g marshmallow extract per kg feed indicated increased levels of total protein and globulin. There were no significant changes in albumin levels (p > 0.05). 2.50 and 5.00 g marshmallow significantly decreased triglyceride and cholesterol levels and increased glucose levels (p < 0.05). A. hydrophila significantly increased AST, ALT, LDH, ALP and CPK activities and plasma glucose, cholesterol, triglycerides and creatinine levels after 10 days (p < 0.05). Total plasma protein, albumin and globulin levels in fish challenged with A. hydrophila were significantly lower than the control group (p < 0.05). Marshmallow extract at 5.00 and 10.00 g can adjust plasma biochemical parameters in fish challenged with A. hydrophila. The results of preclinical studies and pharmaceutical toxicity of marshmallow extract revealed that dietary levels lower than 5.00 g were safe and effective. The results of this clinical study demonstrated that marshmallow extract (5.00 g kg-1 feed) can protect fish against A. hydrophila.
