I am Whippet Collie cross, over the last 18 months I have 3 periods of Pyrexia, and the cause can not be identified. I am only responding to Streroids which is traumatic for both me and my owners. I am wondering if there is something environmental that could trigger this, I would guess I live with an average garden no odd plants and mainly walk at playing fields and a recreation environment. I am taken to the Ashdown Forest, there aren't many trees its mainly ferns & heathers. In the summer months I am not allowed off the lead here because of sheep and deer but attacks seem to coincide with visits & when I am off the lead. Does anyone have any pointers regarding allergies either plant or wildlife?