ADDITION OF YERBA MATE (Ilex paraguariensis A. St. Hil.) IN TILAPIA FEED FOR THE GROWTH OF THE MAYAN CICHLID (Cichlasoma uropthalmus Günther)

Resumen

Native species with aquatic potential can be found in Southeastern Mexico, such as the Mayan cichlid (Cichlasoma uropthalmus Günther), which is commercially valuable and adaptable to farming conditions. The aim of this study was to evaluate the cytotoxicity and the effect of yerba mate (Ilex paraguariensis A. St. Hil.) on the growth parameters of the Mayan cichlid when added to a balanced tilapia feed. Dried, lightly toasted, and crumbled yerba mate from the ROSAMONTE brand was used. The cytotoxicity test was carried out using a bioassay with Artemia salina L. Serial dilutions from the yerba mate aqueous extract (0.78–100 mg mL^-1) were used to determine the mortality of the nauplii after 24 h of exposure and to calculate the lethal dose (DL50). The fish were distributed at random in nine interconnected fish tanks within a recirculation system, with 10 fish per unit. For 45 d, the fish were fed with a commercial tilapia diet (PURINA), homogenously mixed with non-pelletized yerba mate. Three replicates were established per treatment, corresponding to diets with 0, 1, and 2 % yerba mate (treatments T1 to T3). The feed was offered until the fish were satiated three times a day. A probit analysis was carried out to evaluate DL50. The productive parameters were evaluated with normality and homogeneity tests and arcsine transformation for the percentage data, followed by a one-way analysis of variance (ANOVA) and a Tukey test (p < 0.05). The DL50 obtained was 42.42 mg mL^-1, indicating a lack of toxicity. No significant differences were found in the productive parameters (p > 0.05). The best values were recorded in T3 for final weight (0.53 ± 0.04 g), food conversion rate (2.69 ± 0.06), and condition factor (1.86 ± 0.43), and in T2 for weight gain (0.43 ± 0.06 g) and specific growth rate (4.16 ± 0.89 %). The highest survival rate was obtained in T1 (93.3 ± 11.51 %) and T3 (93.3 ± 5.77 %). Yerba mate is not toxic and can be added to the diets of C. urophthalmus, although it does not significantly improve their growth.