OK, I know this is a weird question. 

I`m switching to a new feed and the closest dealer is about 3 hours away, so I`d like to stock up to make the trip less frequently.

I`ve been told that the mice LOVE this feed, and was wondering if storing it in my fairly new (5 year old) aluminum trailer for the winter would be a safe option?  I would cover the drainage holes with a piece of metal so they wouldn`t chew through the rubber mats.  Are there any other places they could get in?

A mouse can get through any area that is a nickle sized and larger. It can also chew through wood, plastic and fiberglass.

Any holes through the trailer body are potential entry spots, caulked or otherwise. We use Decon or an equivalant in our LQs when they are stored. Despite our best efforts, we are unable to completely block the mice from entering, and often find remenants in the Spring.

Covering any holes with metal would be effective. The whole area will have to be secured, otherwise you will be providing a snack bar for many fat critters.

Great suggestion about the freezer - I`ll see what I can dig up.  I do have a couple of plastic bins that I can use, but they won`t hold all the feed.

Would mice be able to enter (chew) through the screens on the trailer?  They`d somehow have to climb the walls (?).  I plan to keep a couple of windows slightly open for winter ventilation.

The mice can and will chew through a plastic bin and plastic garbage cans. I've gone to feed the dogs, and upon removing the lid, encountered beady little eyes upset with my intrusion.

A fridge set upon it's back also works as a storage unit for feed. However, it should not be utilised around children, who can become trapped inside. Some local regulations require that all doors have to be removed from non functioning fridges and freezers.

Depending upon your location, I would say that mice might not be your only concern.  You may be attracting racoons and other small varmints and even bears.

I keep my feed in a large sheet metal box inside my barn that was custom made after racoons ate through my heavy duty plastic garbage cans.

Mice and rats can be particularly dangerous because their droppings can carry the haunte' virus that can be contracted when sweeping.be very cautious when doing so,use a dustpan and avoid sweeping vigorously.

the very worst thing that you can attract with feed being stored,IMO,is a skunk.We attracted one (who probably had our garage closet scoped out some time ago) by leaving cat food sitting out in a bowl for our cat.not much incentive for him to stay around the barn,either.Tonight,I was able to turn on the closet light where said skunk was napping and,at dark,thank God,it came out in search of something to eat,I presume.I put the garage door down and,it won't be raised again until broad daylight.Plus no cat food/no open closet door.

Our exterminator said that it's probably been right at home for a while,because,it's used to our coming/going and the sounds and noises.If it had not been,well,by now,things would have been very unfortunate for us here I imagine.

I also have used chest freezers for storage. Find one with compartments and you can store supplements, powdered meds, ect.  Works great.

I have an Audi that I would think is a pretty tight vehicle especially compared to a horse trailer. I left an onion in the car and mice ate it, they ate my lid to my coffee cup and chewed a larger than normal hole in a bag of grain in my car.

So my mice have onion coffee breath.

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