نوع مقاله : مقاله پژوهشی
نویسندگان
انستیتو تحقیقات بین المللی ماهیان خاویاری، موسسه تحقیقات علوم شیلاتی کشور، سازمان تحقیقات، آموزش و ترویج کشاورزی (AREEO)، رشت، گیلان، ایران
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Introduction: Sustainable aquaculture relies on balanced diets that ensure optimal growth and health. Nanotechnology applications in aquaculture, such as using selenium and iron nanoparticles (Se-NPs, Fe-NPs), show promise for enhancing nutrition. However, their combined effects on intestinal health in beluga are unclear. Therefore, this study aimed to investigate the individual and combined effects of different dietary levels of Se-NPs and Fe-NPs on the intestinal histopathology of juvenile beluga, to identify the optimal and safest supplementation ratio.
Materials and methods: A total of 135 beluga juveniles (with an initial weight of 276.4 ± 32.3 g and an initial length of 40 ± 2 cm) were randomly distributed in 27 fiberglass tanks at 9 different treatments with 3 replicates. Treatments included T1 (control, no added NPs), T2 (1 mg/kg Se-NPs), T3 (2 mg/kg Se-NPs), T4 (100 mg/kg Fe-NPs), T5 (100 mg/kg Fe-NPs +1 mg/kg Se-NPs), T6 (100 mg/kg Fe-NPs +2 mg/kg Se-NPs), T7 (200 mg/kg Fe-NPs), T8 (200 mg/kg Fe-NPs +1 mg/kg Se-NPs), and T9 (200 mg/kg Fe-NPs +2 mg/kg Se-NPs). Before starting the experiment, the fish were adapted to the rearing conditions for a week. The amount of feed during the rearing period was 2-3% of the fish's weight, adjusted according to water temperature. The fish were fed three times a day (8:00-15:00 and 21:00) for 8 weeks. To find the histopathological changes, six fish intestine tissues from each group (two fish of each replicate) were sampled at the end of the experiment. Samples were dehydrated by routine methods and embedded in paraffin wax. They were sectioned by microtome and stained with Hematoxylin and Eosin (H&E).
Results and discussion: Histopathological examination revealed intestinal alterations including villi degeneration, inflammatory cell infiltration in both submucosal and muscular layers, hyperemia, and necrosis. Evaluation of treatment responses showed that the combination of 100 mg/kg Fe-NPs with 1 mg/kg Se-NPs (T₅) demonstrated the most favorable outcome, with tissue integrity comparable to the control group. The T₈ treatment also showed relatively preserved intestinal morphology. In contrast, treatments with higher nanoparticle concentrations exhibited significantly more severe pathological changes, including prominent hyperemia and inflammatory infiltration. These findings indicate that the 100:1 Fe-NPs to Se-NPs ratio effectively mitigates the adverse effects of both elements.
Conclusions: It is concluded that the combined use of iron and selenium nanoparticles at doses of 100 mg/kg Fe-NPs and 1 mg/kg Se-NPs in the diet of beluga is the most appropriate and optimal combination, resulting in minimal histopathological damage to the intestinal tissue. This ratio effectively balances the pro-oxidant potential of iron with the antioxidant capacity of selenium, thereby preserving intestinal health and integrity.
Conflicts of interest: The authors have no conflicts of interest to declare for the publication of the present work.
Funding: This article is a part of the project number 12-32-12-011-98001-991148, which was carried out with the agricultural research education and extension organization (AREEO).
Acknowledgments: The authors are grateful to researchers of the International Sturgeon Research Institute for their support during this study.
کلیدواژهها [English]
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