مقالات رزومه دکتر نرگس عالیشاه

Infectious Pancreatic Necrosis (IPN) is an acute and highly transmissible viral disease in fish. So far, this virus has been identified in different species of fish, but this disease is more severe in the Salmonidae family and causes an acute systemic disease with high mortality, especially in fry and juveniles, hence it is an important economic disease in the Salmonidae farming industry. The causative agent of infectious necrosis pancreas is a virus from the Birnaviridae family, the genus Aquabirnavirus (Aquabirnavirus) without an envelope with a thickness of about 65 nm, which has a double-stranded RNA genome, and serologically, they are divided into two groups, A and B. IPNV is a very resistant virus that has little sensitivity to desiccation and UV rays and can survive in a wide range of salinity and temperature. There are a variety of transmission routes for IPNV, adult fish are carriers of the disease after recovery and can transmit the virus vertically (in eggs) and horizontally (through contaminated feces), the disease can also be transmitted through contaminated water, blood-sucking parasites, Contaminated equipment and fish-eating birds are also transported. Considering that a commercial vaccine with high efficiency and effectiveness for this disease has not been developed yet, familiarity with the characteristics of this disease, its transmission and its spread methods can play an effective role in preventing and reducing the incidence and casualties caused by this disease and in reducing economy loses that caused by this global disease could be useful and effective in the fields of aquaculture in the country.

The aim of this study was to evaluate the effect of hydroalcoholic extract of Aloe vera plant by bath therapy on immunological and blood parameters and control of saprolegniasis in rainbow trout (Oncorhynchus mykiss). After two weeks of adaptation, fish with an average weight of 22±0.27g were randomly divided into 6 experimental treatments with three replications (30 fish repetitions each). After scaling from the caudal fin, the fish were infected with 3×105 zoospores of Saprolegnia parasitica per litter for 4 hours. After that, four treatments received 50, 100, 150 and 200 mg/L Aloe vera hydroalcoholic extract for one hour daily for one week. The other two treatments belonged to the positive control groups (with infection and without Aloe vera treatment) and the negative control group (without infection and without Aloe vera treatment). Evaluation of hematological and immunological parameters at the end of one week of bathing with the above concentrations (first week) and one week after cessation of bathing (second week) showed that hematological, biochemical and immunological parameters of rainbow trout (O. mykiss) treated with 100 mg/l Aloe vera hydroalcoholic extract was significantly increased. Also, at this concentration of hydroalcoholic extract of Aloe vera, minimal losses were observed, which was statistically significant compared to the control group. According to the results, treatment of rainbow trout with saprolegniasis with 100 mg of hydroalcoholic extract of Aloe vera per litter can improve immune function and increase their survival against saprolegniasis.