Creatine plays a vital part in the energy metabolism and physiological roles. It is exclusively found in ingredients of animal origin, so using all‐plant protein‐based diets increases the risk of creatine deficiency. The objectives of this current study were to determine the optimal level of dietary guanidinoacetic acid (GAA) with regard to the nutrient digestibility, growth performance, feed utilization and carcass quality of Nile tilapia (Oreochromis niloticus). The fish (27.33 ± 0.70 g) were fed with five different isonitrogenous and isoenergetic diets for 60 days: T1 was the positive control diet (HF; 6% fish meal inclusion); T2 was the negative control formulated to contain no GAA (NC, free fish meal); and T3, T4 and T5 were NC supplemented with 0.06%, 0.12% and 0.18% of GAA respectively. At the end of the experiment, it was found that growth performance and feed utilization were not significantly different (p > .05) among the groups. However, fish from the T3 and T4 groups had slightly better weight gain and growth rate, as well as improved digestibility of protein, methionine, lysine and histidine (p < .05). Fish fed the dietary GAA at 0.06 or 0.12% had clearly larger width increment than the other groups. This is important as consumers prefer large dorsal muscles. This result from this study showed no adverse effect on haematological parameters, serum biochemistry parameters, fillet texture quality and histopathological change in the liver of Nile tilapia. Therefore, these results indicate that GAA supplementation at 0.06%–0.12% in Nile tilapia diet can potentially improve fish growth and feed utilization without setback on health.

This study evaluated the potential of?spent coffee grounds extract (CGE) as?an?antioxidant supplement in?the diet of?Nile tilapia (Oreochromis niloticus). Four experimental diets with varying CGE levels were formulated: 0% (CGE0, control), 2% ...

This study evaluated the optimal dietary inclusion level of microencapsulated roselle ( Hibiscus sabdariffa L.) calyx extract (MRE) and its effects on growth, physiological responses, pigmentation, and tissue histology in fancy carp ( Cyprinus carpio L.). Fish (27.09 ± 1.14 g) were randomly assigned to 500 L tanks (30 fish/tank) and fed diets containing 0% (MRE‐0), 1% (MRE‐1), 2% (MRE‐2), 3% (MRE‐3), and 4% (MRE‐4) MRE for 60 days, with three replicates per treatment. Fish fed MRE‐2, MRE‐3, and MRE‐4 showed significantly higher final weight ( p = 0.001), weight gain (WG) ( p = 0.003), specific growth rate (SGR) ( p = 0.003), and average daily gain (ADG) ( p = 0.003) than those fed MRE‐0 and MRE‐1, with MRE‐3 and MRE‐4 exhibiting the lowest feed conversion ratios (FCR) ( p = 0.001). Polynomial regression showed a significant relationship between MRE level and SGR ( R ² = 0.9717), with the predicted optimum at 3.76%, which closely aligning with the observed results. No significant differences were found in survival rate (SR) (90%–100%), hepatosomatic and viscerosomatic indices. Hematological parameters showed significant increases in red blood cell (RBC) counts ( p = 0.027), hemoglobin ( p = 0.003), total protein ( p = 0.033), and immunoglobulin levels ( p = 0.001) in MRE‐3 and MRE‐4 groups. MRE supplementation significantly enhanced lysozyme ( p = 0.008) and antioxidant enzyme activities (superoxide dismutase [SOD], p = 0.011; glutathione peroxidase [GPx], p = 0.014), with the highest values in MRE‐3 and MRE‐4. Redness (a ^∗ ) values significantly increased in MRE‐3 and MRE‐4‐fed fish, while lightness (L ^∗ ) and yellowness (b ^∗ ) remained unchanged. Carotenoid and anthocyanin levels in skin, fin, and muscle increased with higher MRE levels. Histologically, MRE‐3 improved intestinal villus height, whereas MRE‐4 induced more pronounced hepatic hyaline degeneration. In conclusion, dietary inclusion of 3% MRE was identified as the optimal level for fancy carp, improving growth, feed efficiency, immune and antioxidant responses, pigmentation, and intestinal development without adverse hepatic effects.

The objectives of the present study were to investigate the effects of Jerusalem artichoke powder supplemented in striped catfish larvae (Pangasianodon hypophthalmus) diet. The experiment was conducted as a completely randomized design with five treatments and three replicates: 0% (JA0; control diet), 0.5% (JA0.5), 1.0% (JA1.0), 1.5% (JA1.5) and 2.0% (JA2.0) of Jerusalem artichoke powder supplementation. Striped catfish (initial mean body weight = 4.24±0.10 g/fish) were fed experimental diet for 8 weeks. The results found that fish fed Jerusalem artichoke powder showed higher growth performance and feed utilization than control group. Moreover, fish fed JA2.0 showed the highest final weight, weight gain, average daily growth as well as lowest feed conversion ratio (p<0.05). However, survival rate showed no significant difference with all treatment groups with the value between 94.27 to 98.10%. Concerning plasma biochemical parameters, fish fed JA2.0 displayed the highest total protein and total Immunoglobulin (p<0.05). In addition, the fish fed Jerusalem artichoke powder showed higher digestive enzyme activities than control group (p<0.05). Liver and intestinal histopathology were investigated. The results showed that Jerusalem artichoke had no negative effect on liver histopathology. In addition, intestinal histopathology showed that fish fed JA1.5 and JA2.0 had the highest villi height (p<0.05) whereas fish that received JA1.0 and JA2.0 exhibited the highest villi width (p<0.05). This study indicates that supplementation with 2% Jerusalem artichoke powder is an optimal level to stimulate growth, enhance immune function, improve feed efficiency, and promote digestive enzyme activity.

Fishes of the genus Rasbora in the Cyprinidae family comprise 88 species