Palatability of animal oils included in the diet of the Mexican axolotl and its effect on growth and survival

Resumen

Objective: The growth, survival, and condition factor of Ambystoma mexicanum juveniles fed with three commercial feed-based diets coated with different animal oils as potential palatability enhancers were evaluated.

Methodology: Three diets were prepared using commercial feed coated with fish, chicken, and krill oil. The experiment lasted 81 days, the food was provided to the axolotls (6 per experimental unit, in triplicate) every 48 h, at 4% of the total biomass. The total weight of each experimental unit was recorded every 15 days, at the end of the experiment individual weight and height and survival were recorded. The following variables were calculated: Fulton's K, specific growth rate, coefficient of variation of final weight and size heterogeneity.

Results: All three treatments showed an increase in total biomass, with a trend towards better performance in chicken and fish oil treatments compared to krill oil. When performing the statistical analysis, it was found that there were no significant differences among the treatments for any of the variables recorded.

Implications: The three oils used in the present study were good palatable agents in the food intake of A. mexicanum.

Conclusions: It is recommended to use chicken oil as an attractant additive in the formulation of a specific diet due to its low cost.