Q: I have one ferret whose poop is runny and yellow, sometimes kinda grainy, but never bloody. He did have an infection but was on antibiotics. Should he still be? He lost weight but eats well.
A: What you are describing is not normal for a ferret, so something is functioning improperly in your ferret’s gastrointestinal system.
The grainy and yellow part is evidence of poor absorption of ingested food material. And when the feces are runny, vital fluid and electrolytes are being lost. If food material is not absorbed, your ferret loses weight and starts looking thin and unthrifty. If the abnormal stools happen infrequently, the changes in your ferret may happen slowly over time and may not be obvious immediately.
Some infections need to be treated for just a week but other infections need a much longer time period to be resolved. Many infections in the gastrointestinal tract fall into the latter category. So, it may be that your ferret required a longer time period on antibiotics. Finally, some gastrointestinal infections can be very difficult to treat and multiple antibiotics are needed before the bacterial infection is properly resolved.