ABSTRACT
The impact of dietary curcumin (CUR) on the growth, antioxidant activity, histomorphology of certain organs, proinflammatory cytokine production, and immune status of Oreochromis niloticus was evaluated. The fingerlings (n = 225, 41.60 ± 0.09 g/fish) were randomly allotted into five experimental groups in triplicate. Fish were fed basal diets complemented with 0, 200, 400, 600, or 800 mg curcumin/kg diet (CUR0, CUR200, CUR400, CUR600, and CUR800, respectively) for 10 weeks. An increase in fish growth was reported in the CUR200 and CUR400 groups. The feed conversion ratio was enhanced by 15% in the CUR400 group. Fish body protein content was increased in the CUR600 group (p ≤ 0.01). Body fat was decreased, and ash content was increased by CUR supplementation in a level-related way (p < 0.05). The villus height was increased in the CUR400 and CUR600 groups. The villus width was increased by CUR supplementation, with the best result found in the CUR600 group. The liver of CUR-fed fish displayed comparatively normal hepatocytes. TNF-α and caspase-3 were significantly upregulated by dietary CUR in a level-related way. The serum catalase activity and GSH level were increased in CUR200 and CUR400 groups. Curcumin supplementation boosted the serum SOD activity and reduced the MDA level. IL10 and IgM levels were increased in the CUR200 and CUR400 groups. Lysozyme activity was increased in the CUR200−400 groups. Serum complement 3 level was increased in the CUR400 group. The percentage survival of O. niloticus challenged with Aeromonas hydrophila was highest in the CUR200-CUR600 groups (100%) and decreased in the CUR800 group (80%). This study concluded that CUR could be added to Nile tilapia diets up to 400 mg·kg−1 to achieve better growth, antioxidant capacity, immune response, and intestinal histology. Long feeding periods on high levels of CUR (600 and 800 mg·kg−1) stimulate inflammatory reactions in fish tissues.
ABSTRACT
The influences of Boswellia serrata resin extract (BSRE) as a feed additive on the growth performance, immune response, antioxidant status, and disease resistance of Nile tilapia, Oreochromis niloticus L. were assessed. One hundred-forty four fingerlings (initial weight: 21.82 ± 0.48 g) were randomly allotted into four groups with three replicates where they were fed on one of four treatments with four levels of Boswellia serrata resin extract 0, 5, 10, or 15 g kg-1, BSRE0, BSRE5, BSRE10, BSRE15, respectively for eight weeks. After the end of the feeding trial, the fish were challenged with Staphylococcus aureus, and mortalities were noted. The final body weight, total body weight gain, and the total feed intake were quadratically increased in BSRE5 treatment (p < 0.01). The protein productive efficiency (PPE) was linearly and quadratically increased in all BSRE supplemented treatments (p < 0.01). Dietary addition of BSRE raised the fish crude protein content and reduced the fat content in a level-dependent manner (p < 0.01). The ash content was raised in the BSRE15 group (p < 0.01). Dietary BSRE supplementation decreased the serum levels of glucose, total cholesterol, triglycerides, and nitric oxide. It increased the serum levels of total protein, albumin, total globulins, α1 globulin, α2 globulin, ß globulin, É£ globulin, Catalase, and SOD (superoxide dismutase) activity, GSH (reduced glutathione), lysozyme activity, and MPO (myeloperoxidase) in a level-dependent manner (p < 0.05). The BSRE15 diet increased the serum level of ALT (alanine aminotransferase) and decreased creatinine serum level (p < 0.05). Dietary BSRE supplementation increased the relative percentage of survival % (RPS) of S. aureus challenged fish. The histoarchitecture of the gills and kidney was normal in the BSRE5 treatment and moderately changed in BSRE10 and BSRE15 treatments. The splenic lymphoid elements were more prevalent, and the melano-macrophage centers (MMC) were mild to somewhat activated in BSRE supplemented treatments. Dietary BSRE supplementation improved the intestinal histomorphology. It can be concluded that BSRE addition can enhance the antioxidant activity, immune status, and disease resistance of O. niloticus to S. aureus infection. The level of 5 g kg-1 BSRE can improve fish growth without causing harmful effects on fish health. The highest levels of BSRE are not recommended as they badly affected the histoarchitecture of many vital organs.
ABSTRACT
The potential effects of cacao bean meal, Theobroma cacao L., (CBM) on the growth, health status, blood biochemical parameters, antioxidant, immune status, physiological parameters, female reproductive performance, and gonadal histological features of fantail goldfish (Carassius auratus, L.) were evaluated using a complete randomized block design with sex as a block. The trial lasted for 60 days. A total of 54 healthy fantail goldfish (36 broodstock females and 18 broodstock males) were randomly allocated into three treatments with supplementation of three levels of cocoa powder 0, 5, and 10 g kg-1 diet, CBM0, CBM5, and CBM10, respectively, with the sex ratio being four females:two males per replicate. The body weight gain and feed conversion ratio of males were increased in the CBM10 treatment (p < 0.05). The CBM10 diet improved relative feed costs (p < 0.05). Females fed on the CBM10 diet had an increase in the serum level of total protein (p = 0.001). Females fed on a diet supplemented with CBM5 showed a decrease in the serum level of triglyceride compared to females fed on CBM0 and CBM10 diets (p = 0.03). CBM10 diet increased the serum superoxide dismutase (SOD) activity of fish compared to CBM0 and CBM5 diets (p = 0.004). Serum levels of testosterone and estradiol were significantly increased in males fed on the CBM10 diet. The female reproductive performance was improved by CBM supplementation (p < 0.05). Ovarian histology exhibited increased granulation and follicle numbers after dietary CBM supplementation compared to the control treatment. Therefore, cacao bean meal can be used as a feed supplement in the diets of fantail goldfish for improving the growth, health status, and female reproductive performance, economic efficiency, and gonadal histological structure.
