Gastrointestinal microflora of captured stellate sturgeon (Acipenser stellatus, Pallas, 1771) from Southeast Caspian Sea, Iran

ماهي ازون برون يكي از با ارزش ترين گونه هاي ماهي هاي خاوياري در دنيا است. هدف از اين مطالعه شناسايي جمعيت ميكروبي مقيم دستگاه گوارش ماهي ازون برون بود از دستگاه گوارش هفت ماهي ازون برون، صد و بيست وسه جدايه قارچي شامل مواردي چون آسپرژيلوس(45.5%)، تريكودرما (8.9%) و كلاديوفيالوفورا(8.1%) جداسازي شد. در ميان جدايه هاي آسپرژيلوس، آسپرژيلوس نايجر بيش از بقيه سويه ها بود. اگرچه ميزان جداسازي قارچ ها از معده بيشتر بود (36.6%) ولي تفاوت معني داري در ميزان جداسازي از معده و ساير بخش هاي دستگاه گوارش وجود نداشت. در كل جدايه هاي باكتريايي اغلب گرم منفي و از خانواده انتروباكترياسه مانند سويه هاي آيروموناس، سودوموناس و سالمونلا بود. بيشتر سويه هاي باكتريايي از ناحيه روده و پيش معده جداسازي شدند(88.2%). به طور خلاصه آسپرژيلوس نايجر و آيروموناس به ترتيب جدايه هاي قارچي و باكتريايي شاخص از دستگاه گواش ماهي ها بودند.

Acipenser stellatus is one of the most invaluable species of Sturgeon fishes in the world. The purpose of this study was to identify the resident microbial community from the gastrointestinal tract (GIT) of Acipenser stellatus. One hundred and twenty three fungi were isolated from the GIT of 7 Acipenser stellatus samples including Aspergillus spp (45.5%), Trichoderma spp (8.9%) and Cladophialophora spp (8.1%). Among different Aspergillus isolates, A.niger was the predominant species. Although, fungi were predominantly isolated from stomach (36.6%), but with respect to frequency of fungal isolates there were no significant differences between stomach and other parts of GI. In general, the bacterial isolates recovered were mostly gram negative and related to Enterobacteriaceae family such as Aeromonas, Pseudomonas and Salmonella species. The most bacterial species were isolated from intestine and pre stomach region (88.2%). It is concluded that A. niger and Aeromonas species were predominant fugal and bacterial microbes isolated from understudy fish GIT, respectively.