I have not heard of this but our gun dogs are certainly exposed to a lot out in the field that can cause problems. For my dogs, I add Purina's Forti Flora probiotic to their food every other "normal" day at home and every day when hunting, traveling or running hunt tests. Also, I take my own water or bottled spring water to my dogs when away from home.
The spores are on plants and they travel by water they swim in. I also take my own water with me. I rotate between RX Probiotics and Proviable but this is not a bacteria - it is also not a fungus - it is fungus like spore around ponds, lakes and standing water. This year the east coast had quite a lot of it. They are working to develop the technology to test the water. MSU has a center but I was told that there are many false negatives as the spores dissolve by the time they actually get to the lab.
Rose Bud - Golden Retriever (June 2012)
Darcy Bud - Flat Coated Retriever (June 2009)
Belle Bud - Golden Retriever (December 2014)