Is it possible for tooth infection to drain straight into a horses digestive system?
Anyone know if it is possible for a horse to have an infection under its tooth or teeth that could be draining directly into its digestive system somewhere somehow? - actually seeping out in its digestive system rather than into its mouth and down its throat? Sorry if its a stupid question but just wondering if its theoretically possible!?
In a word, unlikely. What, exactly do you mean "seeping out into its digestive system"? The digestive system starts at the mouth and ends at the anus, with no communication with the other organs or body cavities except through ducts. (liver, pancreas)
It seems like you specifically meant an infection NOT draining into the mouth or throat and thereby having infectious debris swallowed, but of course that is entirely likely with an open or draining infection in the mouth. However, the "stuff" that drains from an abscess or infection is usually not capable of going elsewhere and infecting other parts of the body--the pathogens in that stuff are all dead or dying already.
The lymphatic system drains all areas of the body and can carry infection-fighting cells to and from various lymphatic "staging areas" (lymph nodes, spleen) but this system of vessels runs alongside arteries and veins and does not communicate directly with the digestive tract, either.
In the case of a really god-awful abscess or deeply-seated infection, you could get formation of a fistula between an infected site and a nearby organ, but since the mouth and teeth are a long way away from anything but the esophagus, I'd say this possibility, although it exists physiologically, is not workable anatomically. In other words, the teeth are too far away from the GI tract to make this sort of situation possible.