تأثير كمبود اسيد‌هاي آمينه‌ چند زنجيره در جيره ماهي صبيتي جوان (Sparidentex hasta) بر فاكتورهاي رشد، فعاليت آنزيم‌هاي گوارشي و تركيب شيميايي بدن

Effects of branched-chain amino acid deficiency in diets on growth factors, pancreatic enzymes activity and whole body proximate of Sobaity seabream juvenile (Sparidentex hasta

در مطالعه‌ي حاضر اثرات كاهش چهل درصدي اسيدهاي آمينه‌ي ضروري چند زنجيره شامل لوسين، ايزولوسين و والين در جيره غذايي بر فاكتورهاي رشد، تغذيه، تركيب بيوشيميايي لاشه و فعاليت آنزيم‌هاي گوارشي ماهي صبيتي به مدت 42 روز در ايستگاه تحقيقاتي ماهيان دريايي بندر امام خميني در تابستان سال 1393مورد بررسي قرار گرفت. اين تحقيق واجد چهار تيمار غذايي در سه تكرار بود كه شامل جيره غذايي شاهد با ميزان و نسبت مناسب از همه‌ي اسيدهاي آمينه ضروري و سه تيمار با كاهش 40% هر يك از اسيدهاي آمينه لوسين (LEU)، ايزولوسين (ILE) و والين (VAL) نسبت به جيره كنترل بود. كمبود اسيدهاي آمينه چند زنجيره جيره غذايي منجر به كاهش شاخص‌هاي رشد، تغذيه، تثبيت نيتروژن، كاهش شاخص چربي احشايي، چربي خام و انرژي ناخالص لاشه و همچنين كاهش فعاليت آنزيم‌هاي گوارشي لوزالمعده پانكراسي گرديد (0/05

On the current study the effects of reducing branched-chain amino acids (BCAA) in diets of Sobaity sea bream in a constant level (40%) on growth and nutritional indices, pancreatic enzymes activity, whole body chemical proximate and amino acids, was assessed. This experiment was conducted in Marine Fish Research Station of Imam Khomeini harbor during July and August of 2014. For these purposes, four different treatments in triplicate were used during 42 days in the base of feeding with semi purified diets containing crystalline amino acids. The control diet was without any deficiency, the leucine (LEU), isoleucine (ILE) and valine (VAL) diets were deficient in leucine, isoleucine, and valine respectively. According to the results, the survival rate was not affected by treatments. Growth and nutritional factors including final weight, the percentage of weight increase, specific growth rate, protein efficiency and nitrogen retention were decreased in deficient diets related to the control but feed conversion ratio increased. Crude lipid decreased in all deficient treatments that showed disorder in lipid metabolism in regards to BCAA deficiency. Leucine, isoleucine and valine content of the whole body showed no significant differences between treatments in spite of deficiency in diets that showed amino acids sparing for these three essential amino acids. Reduction in pancreatic enzyme activity showed the relations of BCAA on secretion and activities of these enzymes.