A new study has found that Convict cichlids, Cryptoheros nigrofasciatus, who experience social stresses are more likely to suffer from digestive disorders.
The research, which was undertaken by scientists from the Center for Behavioural Neuroscience, looked at gall bladder size and bile retention in dominant and subordinate Convicts which had been fed similar quantities of food.
The subordinates had larger gall bladders which were filled with bad bile. The scientists believe that the gall bladder problem may be responsible for reduced growth rates in subordinate fishes.