اثر پروتئین هیدرولیز شده اتولیزی ماهی بر عملکرد رشد، بازماندگی و فراسنجه های خونی بچه فیل ماهی پرورشی (huso huso)

این مطالعه به منظور بررسی اثر سطوح مختلف پروتئین هیدرولیز شده ماهی به روش اتولیز بر عملکرد رشد، بازماندگی و برخی شاخص‌های خونی بچه فیل‌ماهی (huso huso) در یک دوره 48 روزه انجام شد. 750 قطعه بچه فیل‌ماهی با وزن اولیه 0.5 ± 3 گرم به طور تصادفی در 5 گروه آزمایشی شامل گروه شاهد (بدون پروتئین هیدرولیز شده)، 3 تیمار با سطوح مختلف جایگزینی پروتئین هیدرولیز شده با پودر ماهی (تیمار 1، 2 و 3 به ترتیب 2.75، 5.5 و 8.25%) و تیمار 4 کنترل مثبت (غذای تجاری) توزیع شدند. نتایج نشان داد که بچه فیل ماهیان تغذیه‌شده با جیره‌های آزمایشی حاوی پروتئین هیدرولیزشده بازماندگی بیشتری نسبت به گروه شاهد داشتند (0.05>p). شاخص‌های رشد در تیمارهای مختلف واجد پروتئین هیدرولیزشده بیشتر از گروه شاهد بودند، اما این اختلاف معنی‌دار نبود (0.05p). همچنین، تعداد گلبول‌های قرمز گروه شاهد با تیمار 1 اختلاف معنی‌دار داشت (0.05>p). میزان نوتروفیل گروه شاهد با تیمارهای 1 و 3 و تیمارهای 2 و 3 با یکدیگر اختلاف معنی‌دار نداشتند (0.05p). کمترین درصد لنفوسیت مربوط به تیمار 4 بود که با دیگر تیمارها و گروه شاهد اختلاف معنی‌دار داشت (0.05>p). از نظر هموگلوبین، هماتوکریت و شاخص‌های mcv، mch و mchc و درصد مونوسیت و ائوزینوفیل بین گروه‌های آزمایشی اختلاف معنی‌دار مشاهده نشد (0.05

effects of autolytical fish protein hydrolysate on growth performance, survival rate, and hematological indices in farmed juvenile beluga, huso huso

introduction: aquaculture's rapid expansion has led to a high demand for fishmeal, a key protein source in aquafeed. to address this, alternatives like fish protein hydrolysates (fphs) are being investigated. fphs are produced from the enzymatic digestion of proteins in fish processing waste. they have been found to enhance fish growth, feed efficiency, immune responses, and disease resistance. fphs contain functional and bioactive peptides, making them a viable substitute for fishmeal in aquafeeds. they are also a rich source of proteins, amino acids, peptides, and antioxidants, which are beneficial for fish health and welfare. however, it is important to determine the optimal fph inclusion level to avoid potential negative effects from excessive use. this study investigates the effects of different levels of autolytical fhp on the growth performance, survival, and some blood parameters of juvenile beluga, huso huso over a 48-day period.materials and methods: a total of 750 belugas with an initial weight of 3 ± 0.5 g were randomly distributed into five experimental groups: a control group (without fhp), three treatments with different levels of fhp replacing fishmeal (t1, t2, and t3 with inclusion level of 2.75%, 5.5%, and 8.25%, respectively), and a positive control group (commercial feed, t4). the experiment was carried out in 15 tanks (500-l), each containing 50 fish. the inflow water rate was 2 l/min, and the water exchange rate was 6 to 7 times per day in each tank. the fish's growth performance was evaluated by measuring its biometric characteristics every 15 days. hematological parameters were assessed by collecting blood samples from the treatment and control groups at the end of the study. results: the results indicated that the beluga fed the experimental diets containing fhp had higher survival rates than the control group. the growth indices in the fhp treatments were higher than those in the control group, however, the differences were not statistically significant (p>0.05). analyses of hematological parameters showed no significant difference in white blood cell count between treatments 1, 2, 3 and the control group (p>0.05). however, in treatment 4 it was significantly different from all other groups (p<0.05). the red blood cell (rbc) count of the control group was significantly different from that of t1 (p<0.05), with the highest rbc observed in t1. there were no significant differences in neutrophil percentages between the control group and t1 and t3. additionally, t2 and t3 did not differ significantly from each other (p>0.05). however, t4 showed a significant difference in neutrophil percentage compared to the other treatments (p<0.05). in addition, t4 exhibited the lowest lymphocyte percentage, which was significantly different from the other groups (p<0.05). no significant differences were found between the experimental groups in other blood parameters, such as hemoglobin, hematocrit, red blood cell indices, monocyte and eosinophil percentages (p>0.05).