NO! Especially if your pup trailers are configured for tandem axle tractors! Because with that configuration, the landing gear is farther back than it would be on a pup configured for a single axle - the landing gear will be located almost at the middle of the trailer, which means if the load isn't spread out evenly or more towards the rear, your trailer could become nose-heavy and will tip forward and hit the ground when you pull out from under it (leaving the rear wheels high in the air)

Put the weight in the rear half of the trailer if you have to load one end heavier than the other.