Herbaceous plants have attracted increasing attention in the aquaculture industry for their beneficial effects on the growth, health, and physiology of several fish species. Matali (Tradescantia zebrina) is a medicinal herb widely distributed in southeastern Mexico and recognized for its diverse pharmacological properties. This study aimed to evaluate the effects of T. zebrina on growth performance, cytotoxicity, and digestive morphology in the two-band cichlid (Vieja bifasciata), a native species with aquaculture potential. Cytotoxicity of the aqueous extract of T. zebrina was assessed using Artemia nauplii exposed for 24 h to serial dilutions ranging from 100 to 0.78 mg mL-1. Subsequently, diets supplemented with 0% (T1), 5% (T2), 10% (T3), and 15% (T4) T. zebrina were evaluated for their effects on growth performance and digestive morphology in V. bifasciata over a 45-day feeding trial. The results demonstrated that the aqueous extract of T. zebrina was non-toxic, suggesting that its inclusion in fish diets is safe. The highest weight gain was recorded in T2 (2.28 ± 0.43 g), whereas the greatest total length was observed in T3 (5.07 ± 0.04 cm). Survival was highest in T4 (100%). Based on weight gain, specific growth rate, and feed conversion ratio, T2 was identified as the most effective treatment for promoting growth (P < 0.05). In addition, dietary supplementation with T. zebrina produced modifications in digestive morphology. Overall, the inclusion of 5-10% T. zebrina in the diet can serve as a feed supplement without adversely affecting V. bifasciata growth. Further studies involving gene expression, immunological responses, and enzymatic activity are recommended to validate additional potential benefits of T. zebrina in aquaculture.

The objective of this work was to evaluate the effects of three commercial diets for ornamental fish (BIOMAA Spiruflake^® (T1), Tetra TetraMin Tropical Flakes^® (T2), LOMAS tropical fish flakes^® (T3)) compared to a balanced feed for trout (Silver Cup TM (T4)) on the growth, survival, digestive enzyme activity, and intestinal and liver morphology of guppy (Poecilia reticulata) fry after 31 days of feeding. The highest growth was in T2 (0.101 ± 0.004 g) and T4 (0.084 ± 0.008 g) (p < 0.05). Fish fed with T1, T2, and T4 presented the greatest total length. T4 (98 ± 2.828%) and T1 (96 ± 5.656%) had the highest survival. Fish fed with T2 and T4 showed the best growth index values (AWG, SGR, FCR). T4 showed greater alkaline protease, trypsin, and chymotrypsin activity and better in vitro digestibility. The fish fed the T4 diet had the lowest intestinal fold height and the smallest hepatocyte diameter. A cheaper aquaculture diet (T4) significantly improved guppy juvenile nutrition compared to ornamental feeds. Further research should focus on developing species-specific ornamental diets for enhanced fish welfare.