Feeding of Penaeus japonicus Bate (Decapoda : Penaeidae) in pond cultures: size descriptors and food selection

摘要

The feeding pattern of Penaeus japonicus Bate, cultured at different densities, with and without the addition of artificial diets, is investigated in the present paper, to identify any character of prey influencing the feeding preferences of shrimps. Biometric, calorific and gut contents data of shrimps at different developmental stages were recorded, as well as the abundance of benthic prey. A larger size is correlated with an increase of energetic value in the shrimp tissues, as confirmed by the logarithmic relationship between length and weight. Results indicated that artificial diets are chosen at the same rate in each size class and are a good source of energy for shrimps. P. japonicus is able to use different food sources, and its feeding preferences Varied according to its size. The preferred prey were polychaetes, Chiranomus larvae and bivalve molluscs. Young specimens, however, preferred certain items, such as copepods and Abra ovata, while adults also used amphipods and other mollusc species. Results may be related to the different size and shape of prey. [References: 15]