بررسي رژيم غذايي بچه ماهيان كلمه (Rutilus caspicus) در استخرهاي خاكي مركز تكثير و پروروش ماهيان استخواني سيجوال

Evaluation of the Diet of Juveniles Roach (Rutilus caspicus) in Earthen Ponds of Syjwal Bony Fish Breeding Center

اﯾﻦ ﺗﺤﻘﯿﻖ ﺑﺎ ﻫﺪف ﺗﻌﯿﯿﻦ رژﯾﻢ ﻏﺬاﯾﯽ ﺑﭽﻪ ﻣﺎﻫﯿﺎن ﮐﻠﻤﻪ ذﺧﯿﺮه ﺷﺪه در اﺳﺘﺨﺮﻫﺎي ﺧﺎﮐﯽ و ﺑﻬﺒﻮد ﺷﺮاﯾﻂ ﺣﺎﮐﻢ ﺑﺮ اﺳﺘﺨﺮ ﺟﻬﺖ اﻓﺰاﯾﺶ ﻧﻮع ارﮔﺎﻧﯿﺴﻢ ﻏﺬاﯾﯽ ﻏﺎﻟﺐ ﺻﻮرت ﮔﺮﻓﺖ. ﺑﺪﯾﻦ ﻣﻨﻈﻮر، ﭼﻬﺎر اﺳﺘﺨﺮ ﺑﺎ ﺧﺼﻮﺻﯿﺎت ﻫﯿﺪروﺑﯿﻮﻟﻮژﯾﮑﯽ ﯾﮑﺴﺎن در ﻣﺮﮐﺰ ﺗﮑﺜﯿﺮ و ﭘﺮورش ﻣﺎﻫﯿﺎن اﺳﺘﺨﻮاﻧﯽ ﺳﯿﺠﻮال اﺳﺘﻔﺎده ﺷﺪ. ﻧﻤﻮﻧﻪ ﺑﺮداري از ارﮔﺎﻧﯿﺴﻢ ﻫﺎي ﻣﻮﺟﻮد در اﺳﺘﺨﺮ، اﻧﺪازه ﮔﯿﺮي ﻃﻮل و وزن ﺑﭽﻪ ﻣﺎﻫﯿﺎن ﮐﻠﻤﻪ و ﺑﺮرﺳﯽ ﻣﺤﺘﻮﯾﺎت روده و ﻣﻌﺪه آن ﻫﺎ ﻃﯽ 4 ﻣﺎه از اول ﻓﺮوردﯾﻦ ﺗﺎ اواﺳﻂ ﺗﯿﺮﻣﺎه ﺻﻮرت ﮔﺮﻓﺖ. ﻧﺘﺎﯾﺞ ﺣﺎﮐﯽ از آن ﺑﻮد ﮐﻪ ﺑﯿﺸﺘﺮﯾﻦ و ﮐﻤﺘﺮﯾﻦ ﻣﻘﺪار ﺿﺮﯾﺐ ﭼﺎﻗﯽ ﺑﻪ ﺗﺮﺗﯿﺐ 1/196 و 0/633 ﺑﻮده در ﺣﺎﻟﯽ ﮐﻪ ﺑﯿﺸﺘﺮﯾﻦ ﻣﯿﺰان ﺷﺎﺧﺺ ﻏﺎﻟﺒﯿﺖ )Ip( 42/14 ﺑﺮاي ﮔﺎﺳﺘﺮوﭘﻮدا و ﮐﻤﺘﺮﯾﻦ ﻣﻘﺪار آن 2/4 ﺑﺮاي ﺣﺸﺮات آﺑﺰي ﻣﺤﺎﺳﺒﻪ ﮔﺮدﯾﺪ. ﻧﺘﺎﯾﺞ ﺣﺎﺻﻞ از آﻧﺎﻟﯿﺰ Fp ﻧﺸﺎن داد ﮐ ﮔﺎﺳﺘﺮوﭘﻮدا و ﺧﺮﭼﻨﮓ در ﺑﯿﺸﺘﺮ ﻣﻮاﻗﻊ ﺑﻪ ﻋﻨﻮان ﻃﻌﻤﻪ ﻫﺎي اﺻﻠﯽ و ارﮔﺎﻧﯿﺴﻢ ﻫﺎﯾﯽ ﻧﻈﯿﺮ ﺣﺸﺮات آﺑﺰي و دوﮐﻔﻪايﻫﺎ ﺑ زﺋﻮﭘﻼﻧﮑﺘﻮن ﺑﻪ ﻋﻨﻮان ﻃﻌﻤﻪ ﻫﺎي ﻓﺮﻋﯽ ﺑﺮاي ﺑﭽﻪ ﻣﺎﻫﯿﺎن ﮐﻠﻤﻪ در اﺳﺘﺨﺮﻫﺎي ﺧﺎﮐﯽ ﻣﺮﮐﺰ ﺳﯿﺠﻮال ﺷﻨﺎﺧﺘﻪ ﺷﺪﻧﺪ. بررسي ارجحيت غذايي (FP) و محتويات معده و روده بچه ماهيان كلمه در مراحل مختلف گوياي آن است كه در هنگام تغذيه وافر از گاستروپودا ارجحيت غذايي و شدت تغذيه عدد بالاتري را نسبت به ساير غذاها نشان مي دهد

This research was conducted to evaluate the diet of juvenile roach (Rutilus caspicus) stocked in earthen ponds and improve the pond conditions to increase the dominant organisms species. Four earthen ponds with the same hydrobiological properties were studied in the Syjwal bony fish farm. Sampling of the food organisms, measuring the weight and length of the juvenile roaches, and gut examination were carried out over a four-month period from March to June. The results indicated that the highest and the lowest condition factors (K) were 1.196 and 0.633, respectively; while the highest dominance index (Ip) was reported as 42.14 for Gastropoda and the lowest dominance index was reported as 2.4 for aquatic insects. The results of (Fp) analysis showed that the gastropoda and crayfish were mainly considered as the major preys, and organisms such as aquatic insects and bivalves were found as the minor foods in the Syjwal earthen ponds. Evaluation of the food preference (Fp)and the gut content of juvenile roaches in different stages indicate that the gastropoda show a higher food preference and feeding intensity than the other Foods.