Oral bovine serum albumin administration alleviates inflammatory signals and improves antioxidant capacity and immune response under thioacetamide stress in blunt snout bream fed a high-calorie diet.

This investigation looks at the impact of oral bovine serum albumin (BSA) on antioxidants, immune responses, and inflammation signals in blunt snout bream fed a high-calorie diet. 480 fish (average weight: 45.84 ± 0.07 g) were randomly fed a control diet, a high-fat diet (HFD), a high carbohydrate diet (HCD), and a high-energy diet (HED) in six replicates for 12 weeks. After the feeding trial, fish were orally administered with 10% BSA for 10 h, then blood and liver samples from five fish were randomly obtained after 10 h to determine plasma inflammatory markers and inorganic components. Also, the leftover fish were injected with thioacetamide, blood and liver samples were simultaneously obtained at 12, 48, and 96 h, respectively, to determine antioxidant, immune, and inflammatory signals, with survival rates recorded at the same time interval. After 10 h, plasma inflammatory markers such as tumour necrosis factors (TNF-α), interleukin 6 (IL6), nitric oxide (NO), Monocyte chemoattractant protein-1(MCP-1), and cortisol were significantly improved in fish fed HCD and HED as compared to the control. After thioacetamide stress, plasma lysozyme (LYM), complement 3, myeloperoxidase (MPO), and alkaline phosphatase activities, as well as immunoglobulin M, levels all increased significantly (P < 0.05) with increasing time with maximum value attained at 96 h, but shows no difference among dietary treatment. Similar results were observed in liver superoxide dismutase (SOD), catalase (CAT), and glutathione peroxidase (GPX) activities and malondialdehyde (MDA) content, but tended to reduce at 96 h. nf-kb, tnf-α, and mcp-1 tend to decrease with the minimum value attained at 48 h and gradually decrease with increasing time at 96 h. After 96 h of the thioacetamide (TAA) challenge, the survival rate of blunt snout bream fed with an HFD and HCD was significantly lower (P < 0.05) at 48, and 96 h before the administration of BSA. However, no differences were observed among dietary treatments after the BSA administration. Overall, this study indicated that oral dietary administration of BSA might greatly enhance the antioxidant capability and innate immunity and mitigates inflammation signals after TAA stress in blunt snout bream fed high energy diet.

Recent advances in the utilization of insects as an ingredient in aquafeeds: A review.

The aquafeed industry continues to expand in response to the rapidly growing aquaculture sector. However, the identification of alternative protein sources in aquatic animal diets to replace conventional sources due to cost and sustainability issues remains a major challenge. Recently, insects have shown tremendous results as potential replacers of fishmeal in aquafeed. The present study aimed to review the utilization of insects in aquafeeds and their effects on aquatic animals' growth and feed utilization, immune response and disease resistance, and fish flesh quality and safety. While many insect species have been investigated in aquaculture, the black soldier fly (Hermetia illucens), and the mealworm (Tenebrio molitor) are the most studied and most promising insects to replace fishmeal in aquafeed. Generally, insect rearing conditions and biomass processing methods may affect the product's nutritional composition, digestibility, shelf life and required insect inclusion level by aquatic animals. Also, insect-recommended inclusion levels for aquatic animals vary depending on the insect species used, biomass processing method, and test organism. Overall, while an appropriate inclusion level of insects in aquafeed provides several nutritional and health benefits to aquatic animals, more studies are needed to establish optimum requirements levels for different aquaculture species at different stages of development and under different culture systems.

Dietary Aloe vera improves plasma lipid profile, antioxidant, and hepatoprotective enzyme activities in GIFT-tilapia (Oreochromis niloticus) after Streptococcus iniae challenge.

The current study investigated the effects of dietary Aloe vera on plasma lipid profile status, antioxidant, and hepatoprotective enzyme activities of GIFT-tilapia juveniles under Streptococcus iniae challenge. Five dietary groups were designed including a control and 100 % Aloe powder incorporated into a tilapia feed at 0.5, 1, 2, and 4 %/kg feed, which were administered for 8 weeks. Fish fed dietary Aloe at 4 %/kg feed significantly reduced in total cholesterol, while triacylglycerol reduced (P < 0.05) in those fed 0.5, 2, and 4 % Aloe/kg feed compared to unsupplemented ones. High-density lipoprotein was significantly elevated in fish fed 0.5 and 1 % Aloe/kg feed compared to unsupplemented ones, and no significant changes (P > 0.05) were noted in low-density lipoprotein among test groups. Furthermore, high activities of superoxide dismutase, catalase, and glutathione peroxide in liver tissues were observed in Aloe-supplemented fish compared to unsupplemented ones, before and after S. iniae challenge (7.7 × 10(6) CFU cells/mL). Variations were also noted in malondialdehyde activity throughout the trial, but no significant difference (P > 0.05) was observed between groups. Meanwhile, Aloe-supplemented fish reduced serum aspartate and alanine aminotransferase (AST and ALT) activities before and after challenge. Based on the second-order polynomial regression analysis, dietary Aloe inclusion levels less than or equal to 1.88, 1.86, and 2.79 %/kg feed were determined to be suitable in improving plasma lipid profile status, antioxidant, and hepatoprotective enzyme activities in GIFT-tilapia in this study, respectively. Thus, A. vera extracts may be recommended as a tilapia feed supplement to enhance fish antioxidant and hepatoprotective capacities, especially during disease outbreaks.

Dietary Aloe vera supplementation on growth performance, some haemato-biochemical parameters and disease resistance against Streptococcus iniae in tilapia (GIFT).

This study investigated effects of dietary Aloe vera on growth performance, some haemato-biochemical parameters and disease resistance against Streptococcus iniae in tilapia (GIFT). Five groups were designed including a basal diet (control) and 100% A. vera powder incorporated in fish feed at 0.5% 1%, 2%, and 4%/kg feed, which were administered for 8 weeks. Fish fed 0.5%, 1%, and 2% A. vera supplemented diet significantly improved (p < 0.05) weight gain, absolute growth rate and specific growth rate. Feed intake significantly increased in fish fed with A. vera diet at 1% and 2%/kg feed. Feed efficiency ratio, feed conversion ratio, and hepatosomatic index were significantly enhanced in 4% A. vera supplemented fish over unsupplemented ones (p < 0.05). Several haemato-biochemical indices were examined before and after fish were challenged with S. iniae pathogen containing 7.7 × 10(6) CFU cells mL(-1). A. vera supplemented fish showed a significant increase (p < 0.05) in red blood cells, hematocrits (Hb), hemoglobin (Hb), white blood cells (WBC), neutrophils, monocytes, eosinophils, serum total protein, glucose and cortisol after challenge when compared to unsupplemented ones. Meanwhile, 4% A. vera supplemented fish showed a decrease (p < 0.05) in RBC, Hb, Ht, WBC, and mean corpuscular hemoglobin (MCH) after challenge compared to unsupplemented ones and other supplemented ones. In addition, lower mean corpuscular volume values (MCV) (p < 0.05) were observed in fish fed with A. vera diet at 2% and 4% A. vera/kg feed than those fed unsupplemented diet. Unchallenged fish fed 0.5%, 1%, and 2% A. vera showed significantly higher values (p < 0.05) of mean corpuscular hemoglobin concentration (MCHC) than those fed unsupplemented diet and 4% A. vera supplemented diet. There was a significant increase (p < 0.05) in the neutrophil to lymphocyte ratio (N/L) within experimental groups after challenge; N/L ratio in A. vera unsupplemented fish and those supplemented with A. vera diet at 1%/kg feed increased significantly (p < 0.05) throughout challenge period; while those fed 4% A. vera supplemented diet maintained higher values at all experimental stages among groups. There was a significant correlation (p < 0.05, r = 0.53) between N/L ratio and glucose concentration, 96 h after challenge. Aloe had no significant effect (p > 0.05) on the survival of the fish when compared to the control; no mortality was recorded in challenge trial. Overall, our results indicated that dietary aloe supplementation could improve growth, feed utilization, and haemato-biochemical parameters of cultured tilapia.