Mitigating multiple stresses in Pangasianodon hypophthalmus with a novel dietary mixture of selenium nanoparticles and Omega-3-fatty acid

Abstract

Effects of a novel dietary mixture of selenium nanoparticles (Se-NPs) and omega-3-fatty acids i.e., Eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) on mitigating arsenic pollution, high-temperature stress and bacterial infection were investigated in Pangasianodon hypophthalmus. To aim this, four isocaloric and iso-nitrogenous diets were prepared: control feed (no supplementation), Se-NPs at 0.2 mg kg−1 diet with EPA + DHA at 0.2, 0.4 and 0.6% as supplemented diets. Fish were reared under normal condition or concurrent exposure to arsenic (2.65 mg L−1), and temperature (34 °C) (As + T) stress for 105 days. The experiment was conducted with eight treatments in triplicates. Response to various stresses i.e., primary (cortisol), secondary (oxidative stress, immunity, and stress biomarkers) and tertiary stress response (growth performance, bioaccumulation and mortality due to bacterial infection) were determined. Supplementation of dietary Se-NPs at 0.2 mg kg−1 diet and EPA + DHA at 0.2 and 0.4% reduced the primary stress level. Exposure to arsenic and temperature (As + T) and fed with control diet and EPA + DHA at 0.6% aggravated the cortisol level. Anti-oxidative enzymes (Catalase, superoxide dismutase, glutathione peroxidase and glutathione-s-transferase) and immunity (Nitroblue tetrazolium, total protein, albumin, globulin, A:G ratio, total immunoglobulin and myeloperoxidase) of the fish were augmented by supplementation of Se-NPs and EPA + DHA at 0.2 and 0.4%. Neurotransmitter enzyme, HSP 70, Vitamin C were significantly enhanced (p < 0.01) with supplementation of Se-NPs at 0.2 mg kg−1 and EPA + DHA at 0.2 and 0.4%. Whereas total lipid, cholesterol, phospholipid, triglyceride and very low-density lipoprotein (VLDL) were reduced (p < 0.01) with the supplementation of Se-NPs at 0.2 mg kg−1 diet and EPA + DHA at 0.2 and 0.4%. Tertiary stress response viz. growth performance was also significantly enhanced with supplementation of Se-NPs at 0.2 mg kg−1 and EPA + DHA at 0.2 and 0.4% reared under As + T. Whereas arsenic bioaccumulation in fish tissues was significantly reduced with dietary supplementation of Se-NPs and EPA + DHA. Cumulative mortality and relative percentage survival were reduced with Se-NPs at 0.2 mg kg−1 and EPA + DHA at 0.2 and 0.4%. The investigation revealed that a novel combination of Se-NPs at 0.2 mg kg−1 and EPA + DHA at 0.4% followed by 0.2% has the potential to alleviate temperature stress, bacterial infection and arsenic pollution. Whereas diet containing Se-NPs at 0.2 mg kg−1 diet and EPA + DHA at 0.6% was noticeably enhanced the stress in P. hypophthalmus.

Robust and universal predictive models for frictional pressure drop during two-phase flow in smooth helically coiled tube heat exchangers

“…Recently, intelligent approaches have been widely utilized for modeling thermal and hydrodynamic characterizations of various systems 53 , 54 . The multilayer perceptron (MLP) is the most famous approach among several available neural networks, which has been broadly used for modeling complex systems 55 – 58 . Figure 1 shows the configuration of the present MLP network for modeling of two-phase FPD in coiled tubes.…”

Dietary Chlorella vulgaris mitigated the adverse effects of Imidacloprid on the growth performance, antioxidant, and immune responses of common carp (Cyprinus carpio)

“…To our best knowledge, in fish, Total protein, Albumin, and Globulin are known as important components of the innate immune system (Rao et al, 2006). Albumin is needed for the transportation of metal, hormones, vitamins, drugs, bilirubin, and fat metabolites and regulates the free available hormones and is mainly secreted from the liver in fish to fulfill the high energy demand during stress through protein synthesis (Abdel-Tawwab and Ahmad, 2009;Kumar et al, 2021). In the present investigation, the Albumin was less than Globulin, however rapid utilization of Albumin to meet the immediate energy demand could also increase its rate of synthesis in the liver.…”

“…However, in some cases, no significant differences were observed between Chlorella vulgaris dry powder treatments while in many immunity indices; the highest indices were observed in the fish fed with a diet containing the 5% Chlorella vulgaris dry powder level. The primary stress response is Cortisol which is elevated in fish exposed to poison and high temperature (Kumar et al, 2021). Imidacloprid can target several sites on a hypothalamuspituitary-internal axis which might be the reason for increased Cortisol secretion in this study.…”

Selenium in Bodily Homeostasis: Hypothalamus, Hormones, and Highways of Communication

“…Like in mammals, GCs are a major stress hormone in fish and are secreted by the hypothalamic–pituitary–inter-renal (HPI) axis, analogous to the HPA axis in mammals [ 237 , 238 ]. One study found that treatment of iridescent sharks ( Pangasianodon hypothalamus ) with selenium nanoparticles effectively protected against raised cortisol levels following arsenic and heat stress [ 239 ]. A contrasting result was found in gilthead seabream ( Sparusaurata ), where long-term supplementation with hydroxy-selenomethionine (OH-SeMet) resulted in elevated plasma cortisol levels following a crowding stress test [ 240 ].…”