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Nanotechnology has recently played a key role in tackling many aquacultures issues. Hence, the present study targets the evaluation of dietary inclusion of nano iron oxide (nFe

The current perspective is a pioneer to assess the efficacy of Salvia officinalis leave powder (SOLP) on growth, intestinal enzymes, physiological and antioxidant status, immunological response, and gene expression of Common carp (Cyprinus carpio). We also looked into fish resistance after being challenged with Aeromonas sobria, a pathogenic zoonotic bacteria. Fish (N = 120) were fed four different experimental diets in triplicate for 8 weeks. The control diet (SOLP0 - without SOLP); meanwhile, the other three diets included SOLP of 2, 4, and 8 g kg

To further optimize practical diets with respect to IAA requirements, this study was conducted to confirm and refine the tryptophan requirement, which is a potentially limiting AA in our matrix of ingredients. In order to ensure the best information on Trp requirement, our study used wide range of Trp levels and quality of fit of the models for calculating requirement estimates. Twelve iso‑nitrogenous and isoenergetic diets (practical defined ingredients) containing 30% protein and 8% lipid were formulated to meet the nutritional requirement of juvenile Nile tilapia (Oreochromis niloticus) with the exception of tryptophan. A basal diet deficient in tryptophan was assigned to meet all other known nutrient requirements of the Nile tilapia. L-tryptophan was then added to the basal diet at 0.04% increments to produce tryptophan levels ranging from 0.21 to 0.61% of the diet. The diet which supported the best performance of Nile tilapia in previous work, was used as a reference diet. Each diet was fed to three replicate groups of juvenile Nile tilapia (7.9 ± 0.1 g) in a recirculation system for eight weeks. Saturation kinetic model, broken line models with linear or quadratic ascending portions, were used to evaluate dose-response relationships of thermal-unit growth coefficient, apparent net protein retention, tryptophan retention against dietary tryptophan. Akaike weights were calculated and used for model selection in addition to the model's overall R2. The tryptophan requirement of juvenile Nile tilapia was estimated at 0.31% (0.25–0.37%), 0.33% (0.26–0.39%), 0.25% (0.24–0.25%), 0.27% (0.25–0.31%) of the diet for optimum growth, tryptophan deposition, feed efficiency, and apparent net protein deposition (95% of maximum value), respectively.

Ammonia is a critical hazardous nitrogen metabolic product in aquaculture. Despite trials for its control, ammonia intoxication remains one of the most critical issues to overcome. In this study, we explored the modulatory effect and potential mechanism by which Yucca schidigera extract (YSE) can ameliorate ammonia intoxication-induced adverse effects on tilapia health and metabolism. A total number of 120 Nile tilapia were evenly assigned into four groups with three replicates each. The first group served as normal control group, the second group was exposed to ammonia alone from the beginning of the experiment and for four weeks. The third group was supplied with YSE in water at a dose of 8 mg/L and exposed to ammonia. The fourth group was supplied with YSE only in water at a dose of 8 mg/L. YSE supplementation succeeded in improving water quality by reducing pH and ammonia levels. Moreover, YSE supplementation markedly alleviated chronic ammonia-induced adverse impacts on fish growth by increasing the final body weight (FBW), specific growth rate (SGR), feed intake and protein efficiency ratio (PER) while reducing the feed conversion ratio (FCR) via improvements in food intake, elevation of hepatic insulin-like growth factor (ILGF-1) and suppression of myostatin (MSTN) expression levels with the restoration of lipid reserves and the activation of lipogenic potential in adipose tissue as demonstrated by changes in the circulating metabolite levels. In addition, the levels of hepato-renal injury biomarkers were restored, hepatic lipid peroxidation was inhibited and the levels of hepatic antioxidant biomarkers were enhanced. Therefore, the current study suggests that YSE supplementation exerted an ameliorative role against chronic ammonia-induced oxidative stress and toxic effects due to its free radical-scavenging potential, potent antioxidant activities and anti-inflammatory effects.

An 8-week feeding trial was conducted to evaluate the production performance of all male Nile Tilapia (Oreochromis niloticus) fed diets supplemented with increasing levels of trace mineral premixes (copper, selenium, zinc, iron, manganese) from inorganic (I) and organic (O) sources. A practical trace mineral basal diet was developed using only plant ingredients. Nine experimental diets were prepared from the basal formula by adding graded levels of inorganic or organic trace mineral premixes to deliver 0 (control diet), 0.5, 1.0, 2.0 or 4.0 times the micromineral requirement for tilapia as stated in the NRC (2011) . Juvenile Nile tilapia (initial weight 7.13 ± 0.24 g) were randomly stocked into 50-L aquaria at 25 fish per aquarium. Each of the nine treatments was replicated five times except treatment 8 (I-4) with four replicates. According to the results of our study, there were no significant effects of trace mineral premix levels and sources on the growth performance, survival rate and whole body proximate composition of Nile tilapia (P > .05). However, the trace mineral concentrations in the whole body and fillet were significantly influenced by the dietary levels of premixes. With the exception of selenium, there were no major differences in the micromineral contents in the fillet between fish fed the organic or inorganic sources of microminerals. Fish fed diets with organic selenium (Selplex, Alltech®) had significantly higher selenium levels in the fillet with the adjusted mean of 0.0191 mg/100 g fillet compared to 0.0161 mg/100 g in fish fed inorganic selenium (Na-Selenite).

A 10-week growth trial was conducted to optimize the amino acid (AA) profile of diets offered to Nile tilapia. Nine diets with different AA profiles were formulated to evaluate the response of this species to the shift of dietary AA profiles. A diet containing 30% crude protein, supporting the highest growth rate of fish in previous work, was used as a reference diet (30AAR), while a 24% crude protein diet (24AAR), which previously induced growth depression, was used as a basal diet. This diet contained 22.2% crude protein derived from intact proteins and 1.8% from crystalline AAs (CAAs). All of the indispensable AAs (IAAs) in the 24AAR diet were then enhanced to match levels of the 30AAR diet to confirm potential limitation of IAAs (24AAE). Dispensable AAs (DAAs) were after that incorporated at 4% of the diet to elucidate their role in the low protein diet (24AAE + N). Finally, to confirm possible limitations of one of the AA (Trp, Ile, Arg, His, Val) these IAAs were individually dropped from diet 24AAE + N. Results indicated that supplementation of DAA in the lower protein diet is needed to overcome limitations of nonspecific nitrogen and optimize protein efficiency. Growth performance of fish fed diets without DAA supplementation was not comparable to those of fish fed diets supplemented with DAA in spite of their IAA supplements up to an IAA profile of the reference diet. In our ingredient matrix, Val is likely limiting and the supplementation of this IAA is needed to improve the performance of fish.