Anthony,
Fred is absolutely right on all counts. Wild-caught Drymarchon are typically living courses in parasitology, mainly due to the wide varieties of prey items they use. I have a pair of Blacktails that were wild-caught. As soon as I got them I did fecal exams on both. Both had the following:
1. Roundworms
2. Pinworms
3. Tapeworms
4. Coccidia
5. Strongyloides
6. Entamoeba
It took me about 6 months to get these things down to acceptable levels, especially the Coccidia. Any of these can cause regurgitation or vomiting and loss of appetite. It is important to recognize the difference between regurgitaion and vomiting when you are combating this kind of thing. Regurgitation typically occurs with 24 hours or so of eating and the food item will show little sign of digestion. Vomiting can occur up to a week or so after eating and the food item will be heavily digested. Regurgitation will usually indicate a problem with the upper digestive tract, between the throat and the stomach. Vomiting will normally indicate a problem with the lower digestive tract between the stomach and the vent. This distinction can be key in figuring out what sort of bug is causing the problem as some tend to concentrate in the upper digestive tract, while others tend to concentrate in the lower digestive tract. Generally, in cases of regurgitation, I look to environmental problems first such as temperature, stress, etc. In cases of vomiting, I look first at intestinal parasites. One parasitic cause of regurgitaion is a Coccidian called Cryptosporidium. This one is bad, bad news. In snakes it tends to concentrate in the stomach, thus the regurgitation. In Lizards it tends to concentrate in the intestines and will cause vomiting. It is difficult, if not impossible to cure. The normal meds you would use for Coccidians, such as Sulfadimethoxine, seem to have no effect whatsoever. It also can spread through a collection like wildfire...a good reason to quarantine everything for at least 6 months before bringing it into your collection. Crypto is not easily found by normal methods, such as fecal flotations or direct smears unless you are specifically looking for it. It requires a special staining process (an Acid-fast staining) to make it visible under a light microscope and it is much tinier than other parasites you would normally look for.
Fred's advice was sound...all of it. Get a sample to a vet, as soon as you can. If he (or she) does not find anything in a float that would explain the problems, have him do a stomach lavage and check for Crypto. In the meantime, get these snakes away from the rest of your collection, including all cages and furnishings.
