Feeding ecology and Food compostition of the black carp mylopharyngodon piceus and the grass carp ctenoph -aryngodon idella inhabiting the fish pond of Al - Abbassa fish hatchery with emphasis given to vector snails

ABSTRACT

In this study, the stomach contents of M. piceus and C. idella collected from earthen fish ponds at Al-Abbassa Fish Hatchery during different seasons were examined. Food items were analyzed by three methods, including the numerical percentage [N%] of point assessment [P%] and frequency of occurrence [F%]. A comparison of the different methods emphasized the importance of snails as the major food resources in the diet of M. piceus during all seasons. During winter, the stomachs of the most fish samples collected from fish ponds were empty or had traces of food. The index of relative importance [IRI] indicated that the snails were the major food category in the diet of M. piceus during summer, autumn and spring represented by 7331, 9696 and 11670, respectively. Plants were the main food item in the diet of C. idella during summer [4604], meanwhile they ranked the 3rd in the relative importance in the diet during autumn and spring. Artificial fish food came as the 2nd food item in the diet of M. piceus during summer [1398.9] and autumn [5896.3], but it was completely absent in spring. It is considered the main food item in the diet of C. idella during autumn [10384.3] and spring [6293.5] and ranked the 3rd in summer [1395.5]