Study of tench (Tinca tinca) diet of Lahijan Amirkelayeh wetland

The diet of Tinca tinca in Lahijan Amirkelayeh Lagoon was in studied in four season of 2001.Fishes were caught by gillnet, common haul science, castnet and dipent. Fishes were biometry, age determ ation، necropsy and intestine contents were recognized after catch. According to obtained results from 178 Amirkelayeh lagoon Tinca tinca 1+ 7 + age groups,average total lenght, weight, relative length gut, index of fullness and fullton's condition factor were respectively 26.3 cm , 382.5 gr , 0.72 , 187.2 and 1573.1 . Natural diet of Tinca tinca includ, 17groups of live foods like odonata, snail, water plant, trichoptera , chironomidae, hemiptera, ephemeroptera, Perca fluviatilis, diptera, gammarus, tubifex, plant seed, simulium, water bug, water tick, zeoplankton and phytoplankton during sampling in 2001 . In this fed foods, ahytoplankton , snail and hemiptera had highest frequency percentage (68.53%,65.7% and 34%) and water tick,water bug, trichoptera, ephemeroptera , diptera and Perca fluviatilis had lowest frequency percentage (each with 1.1%). There for, according to obtained information, Tinca tinca is a phytoplanktonvores , zeoplanktonvores , bentosvores, plantovores and carnivores .That by account of this food habitis and also relative lenghth gut , we should say that Tinca tinca is an omnivores.Meanwhile , Tinca tinca food habits and food factors were dependent of season ,age and sex changes . Key word: Amirkelayeh lagoon , Tinca tinca , Natural diet. over 87% ( ranged from 87.7 to 112 % ) . The within laboratory relative standard deviations [RSDr] were less than 16.6% ( ranged from 4.3 to 16.6%). Subsequently 47 samples of shrimp were collected from the southern provinces of Iran and were analyzed for the presence of and aflatoxins B1 , B2, G1, and G2. Aflatoxin B2 contamination only detected in one sample at a level of 1.71 ppb . Such a low contamination level may pose a negligible risk to human health. Key words: Aflatoxins, Immunoaffinity, Mycotoxinns, Matrix, Drug, toxins and environmental contaminants.