Gut Contents Study of White Leg (Litopenaeus vannamei) Shrimp during a Culture Period from Earthen Ponds in Delvar of Bushehr

In this research، gut contents of white leg shrimp Litopenaeus vannamei were investigated for 113 days culture period at earthen ponds in Delvar of Bushehr، by sampling every 15 days. Results showed that artificial food had highest weight percentage in gut contents (foregut، midgut، and hindgut) following in order by detritus، zooplankton، phytoplankton، and macro-benthic. In the beginning of culture period، macro-bentic were observed in larval gut contents while other food items were throughout culture period. The maximum occurrence of detritus in gut contents was at 26 and 40 days-old larvae while highest phytoplankton was obtained at 86-days-old larvae in end of culture period. The zooplankton had approximately similar amounts throughout culture period in different parts of gut، while macro-benthic only observed at 26-old-days larvae with maximum amount at foregut and midgut. The mean highest gut fullness attained at foregut (0. 95 %) and lowest at hindgut (0. 20 %). The dominant color of gut content was green-brown in all parts of gut that could be due to consumption of natural pond products. This study illustrated that most consumed food items in L. vannamei was prepared by natural pond foods. In addition، detritus and plankton have most important in L. vannamei during culture period.