A number of gastrointestinal conditions must be considered: bacteria, viruses, parasites, and toxic chemicals and plants. The deworming may not be effective if drug resistance has developed. It is advisable to do a fecal analysis because it could be coccidiosis or cryptospordia — deworming medications affect neither of these. As for toxicity, survey the environment for sources of ingested chemicals and grazed foreign plants. Relation of fed diets is to be considered, as for overconsumption and drastic changes in diet, which commonly causes sudden death by poisons produced by the bacterium Clostridium perfringens Type D.
