First attempt to fill gaps in the feeding of the axolotl Ambystoma mexicanum (Shaw & Nodder, 1798) in captivity: attractability of some animal oils. Atractability of animal oils for Ambystoma mexicanum

Abstract

Objective: To determinate the attractability of four oils, fish, chicken, krill and red crab (Pleuroncodes planipes) for Ambystoma mexicanum juveniles, evaluating their feeding behavior using a Y aquarium.
Design/Methodology/Approach: Ten axolotls were used per test, fasted for 48 hours. Gels with oils were prepared using gelatin and poured into petri dishes and refrigerated until gelation. A recording of the test was made using two video cameras. In the feed chamber the gelled oil was placed and allowed to stand for 15 minutes. On the other chamber a gelled disk with no other ingredient than gelatin and water was placed. The video recording began once the 15 minutes of gel permanence had finished, removing the barrier so that the axolotls could move through the rest of the aquarium.  All tests were carried out with a recording time of 30 min.
Results: Fish oil demonstrated a lower attraction effect compared to krill, red crab and chicken oils (P <0.05), while chicken oil (30.00 ± 1.73) doubled the attractive effect of krill oil (16.00 ± 1.00).
Limitations of the study/implications: It was necessary to condition a room with controlled environmental temperature for A. mexicanum (18 ± 1 °C).
Findings/Conclusions: Krill and chicken oil are good feeding effectors for A. mexicanum causing positive feeding behavior. The use of chicken oil is desirable because of its low cost compared to krill.