Today I opened up the first of two bags of feed I had picked up from the feed store a couple weeks ago and inside found a dark dirt-like substance clinging to the sides of the bag. On closer inspection I realized the dirt was moving. I took that bag plus the other one from the batch back to the feed store and they confirmed grain mites and refunded the cost.
This is the first time I've found grain mites in my feed and after reading a little bit on the web I'm wondering a couple things.
1- I stored those bags in contact with bags of alfalfa pellets. I didn't see any evidence of the mites outside the infected bags, and after opening one of the bags of alfalfa I didn't see anything inside it either. Should I be throwing out these bags just as a precaution? Do grain mites even infect hay pellets?
2- How does grain mite infected feed happen? I've been using this same feed for well over a year and not had a problem before. I can get it from 2 feed stores in my area, but neither of them stock it (always special order) so it's not like it's been sitting on their shelves for a long time. If I do get another infected bag, should I consider switching suppliers? Or is the problem with the brand?
3- I store open bags in plastic garbage cans. I already cleaned out the one that the infected bag was in with hot soapy water. Is there anything I should do to clean up the shelf where the unopened bags were stored? I figure I'll vacuum them with the shop vac, but was wondering if I should do more than that? Maybe spread some food grade DE?
I store my grain in my garage- because the gas furnace is in there it's stays reasonably warm (though colder than the house) and pretty dry. Not ideal conditions for grain mites.