The posting of the skeleton models went viral on the social media with many Facebook users criticising his mercy killing of two pets as cruel, inhumane and unethical as they were still alive and should not be killed to make skeleton models.
Dean of the Faculty of Science Mrs Supha Harnnongbua said an investigation was conducted after the posting of the student went viral on the social media.
The student posted that the cat and the rabbit he used to make skeleton models died from his mercy killing.
Mrs Supha said it was found that the incident took place in 2013 when the student was then a first year student majoring in skeleton collection of the Zoology Section study.
The lecturer in the study had given carcasses of Guinea pigs to each student for experimental making of skeleton models.
But this student had damaged the carcass and requested for permission to use the cat which died a few days earlier to make the skeleton model instead. His request was accepted.
However she said his posting on Facebook about the mercy killing was just his impetuous decision, and he has apologised for what he posted which was not true.
Investigation also showed the rabbit belonged to his neighbour and it had died a few days earlier.
She said what this student posted on his Facebook was just a matter of misinformation.
She said that student was given a warning already but still the university will consider disciplinary punishment on him to set a precedent for other students not to repeat such unethical action.
National Laboratory Animal Centre director Prof Pradon Chatikavanija said normally any scientific experiment on animal needs to seek prior permit and the experimented animal must be in good health and is not infected.
In any case of mercy killing of the experimented animal, it needs to follow legal procedure stipulated under the Law on Experimented Animals, and ultimately the animal must be legally acquired, he said.