My pit bull lays outside for long periods of time. This morning she was laying outside when I notice medium size bumps all over her body. She has about 50 of them. She is in no pain. The bumps itch, which makes me assume that they are some sort of bites. We gave her benadryl. We live in an urban city. She lays outback on our deck. There are a few plants around the area, but none directly in the yard. Any ideas of what could be causing this. We lived in the same house for about 2 1/2 years and nothing like this has happened before.