A field trials were conducted to assess the helminth parasites of 12 marsh frogs (RANA RIDIBUNDA RIDIBUNDA) in the Anzali, Astara and Aghbaba regions in the north of Iran in May 1994. Experimental results showed that 83.8% of the Anzali marsh frogs were infected by one or two kinds of metacercarian cysts of digenetic trematodes. The helminth parasites were included Skrjabinoeces breviansa, S. smilis, Gorgodera dollfusi, Opisthioglyphe RANAe, Prosotocus confusus, Encyclometra colubrimurorum and Codonocephalus urniger. Frogs collected from the Astara region was infected by the helminth parasites such as Diplodiscus subclavatus, P. confusus, C. urniger and Cosmocerca ornata. There were only one digenetic trematodes cysts such as Pleurogenoides medians in the Aghbaba region. In this paper, except the S. smilis, C. urniger and O. RANAe we report 7 new helminth parasites in the north Iranian freshwater system for the first time.

Diazinon is the one of organophosphate insecticides that is used extensively for agricultural activities, and recognized as an environmental pollutant in the world. This research was done for study of the diazinon effect on blood level of hepatic enzymes. After survival and Lethal dose test of diazionon, 72 male RANA RIDIBUNDA with weight range of 100 to 150 gram were collected from Anzali wetland and divided to 9 groups (n=8 in each group) contain of control group that were exposed to water without diazinon and 8 treatment groups that were exposed to 30, 60, 90 and 120 µgram/liter diazinon and for each concentration, two period of time respected: One day and one week after diazinon exposure. Then blood samples prepared from frogs and centrifuged with 2500 rpm for 10 minutes and serum isolated for photometric measuring of alkaline phosphatase (DGKC method) and aspartate aminotransferase and alanin aminotransferase (IFCC method). Results indicated those ALP enzymes were increased significantly by 30, 60, 90 and 120µgram/liter of diazinon at 24 hours and one week after treatment. For ALT and AST this difference was significant for 60, 90 and 120 µgram/liter in one week time period (P<.05).Rising of hepatic enzymes probably show that hepatocytes were injured and then regenerated.Results of this study demonstrated the increasing effect of diazinon on blood level of hepatic enzymes and detoxification response of liver in basis of acute model of diazinon intoxication.

BACKGROUND: Antimicrobial peptides with relative length (2-100 amino acids) and positive charge (pure charge (+9)-(+2)) are amphiphilic that isolated from a wide range of animals. Recently, these peptides have been known as a part of innate immune response. Nowadays, more than 500 antimicrobial peptides from animals have been reported.OBJECTIVES: The aim of this study was to evaluate the anti-Candida effects of cationic peptides derived from RANA RIDIBUNDA skin.METHODS: In this study, using alcohol-acid technique, peptides of frog’s skin were isolated and purified by Sep-Pack and Sephadex column. Then the anti-Candida activity (Fluconazole Resistance C. albicans, Fluconazole Sensitive C. albicans, and C. glabrata) of the peptides in different concentrations were evaluated.RESULTS: Regarding to statistical analysis, peptides in concentration ranging from 25 to 100 mg/ml had the most anti-Candida activities. In respect to different understudy Candida species, these agents had the less effect on the Fluconazole Resistance C. albicans (p<0.05).CONCLUSIONS: The anti-Candida effects of cationic peptide obtained from frog skin are approved in this study.

According to many literatures RANA RIDIBUNDA probably has the potential to become a commercial species which was exploited at least once about 30 years ago in Anzali wetland region. In this study, the larval growth was surveyed at 5 stations in Anzali wetland and the sampling was performed by sieve every 10 days and 2200 larvae were measured and grouped in length frequency classes. The population estimation was done at 20 stations by Jolly-Seber and Leslie methods. The results showed that the maximum length and weight of larvae were 87.7 mm and 5.1 gr respectively. Frequency of total length classes higher than 56 mm and body length more than 26 mm were very little. The findings showed that total frequency of larvae decreased as time proceeds. Mortality rate of larva was very high about 97 % and first metamorphosed specimen was observed at early June after about 43 days. According to this study the average survival rate of RANA RIDIBUNDA in all studied stations was 0.64±0.16 percent and the average population density was 1.033 N/m2. Maximum sustainable yield was estimated to be about 0.304 individual/m2.

One of the most interesting phenomenons among some animals is color polymorphism between different populations of the same species. This variation in color is likely due to the adaptation of animals with the environment in order to escape from the predator or nearing to their prey. Here, we investigated this phenomenon in RANA RIDIBUNDA which is found throughout the Iran. We demonstrated that there are seven different morphs among populations of this frog. Of these, frequency of the morph 3 is more common than the others. We have also shown that there is no clear relationship between the gender and morphs and it seems these have been evolved independently.

Amphibians have a large variety of antimicrobial peptides that serve as natural innate barriers limiting microbial infection or, in some instances, act as an integral component in response to inflammation or microbial infection. A novel peptide with antibacterial effects and without hemolytic activity was purified from skin secretions of RANA RIDIBUNDA by multisteps cation-exchange FPLC, reversedphase HPLC and was called Ridibundin 1. Circular dichroism spectra revealed that this peptide strongly prefers to form an amphipathic ل-helical structure in the presence of 50% trifluoroethanol. Acting as wide-spectrum microbicides against a variety of bacteria, Ridibundin 1 also shows no hemolytic activity on erythrocyte. These properties reveal its unique characteristics and potential therapeutic application.

The purpose of this study was to examine the acute and sub-acute effects of diazinon on histopathological parameters of liver tissue and blood level of hepatic enzymes of male common frog (RANA RIDIBUNDA). Frogs were assigned to 9 groups (n=8, meaning 8 frogs in each group): control and treatment groups with 30, 60, 90 and 120 mg/L diazinon in water for one day or one week. Hepatic enzymes containing alanine transaminase (ALT), aspartate aminotransferase (AST), and alkaline phosphatase (ALP) were measured using biochemical kit. All ALP values were significantly different between the control group and one-day and one-week diazinon exposed groups. Hepatocyte changes were observed only for diazinon concentrations greater than 60 ml after one week. The most important characteristics of the affected cells were hyperplasia and chromatin formation. Results show that sub-lethal concentrations of diazinon have an increasing effect on the blood level of hepatic enzymes, which probably indicated the detoxification response of liver on the basis of diazinon sub-lethal effect model.