I didn't like the look of the swelling on Dawn's neck yesterday evening - the swelling was larger, hot and sensitive to the touch, and Dawn seemed somewhat uncomfortable, despite the bute in the afternoon. I was also concerned that, if the swelling got any bigger, it might begin to impinge on her windpipe or throat. If the swelling were due to an infection like cellulitis, that can get out of hand very quickly. I've never seen cellulitis except in the legs of a horse, but this looked like something similar to me. So I called the vet, who came a couple of hours later.
Dawn is always very cooperative for the vet, which comes in handy at times like this. Since infection was a real possibility, the vet drew blood. Dawn's temperature was still normal, and she was bright-eyed but uncomfortable in the swollen areas. The skin irritation/flakiness was probably due to a reaction to the venom in the stings, whereas the swelling could be due to an overactive immune response to the stings, although the fact that it popped up several days later made it more likely that it was an infection.
The program is bute twice a day for several days, hydrocortisone creme on the irritated skin, hot packs on the swelling when I can, a paste of baking soda on the swollen areas overnight and oral antibiotics (Uniprim once a day). I'm glad I had the vet out, as the bloodwork report this morning showed an elevated white cell count and also changes in the relative composition of types of white cells, both of which indicate infection. Oddly enough, the bloodwork also showed that Dawn was dehydrated, although that wasn't evident on examination or by her demeanor, so she's also getting electrolytes twice a day. The vet recommended shaving the affected area to improve the treatment with hydrocortisone and also the baking soda paste, but I opted not to do that as our flies are just too bad for Dawn to have no hair to protect her.
This morning, the swelling was much reduced - her skin is actually pleated in one area where it had been especially swollen - I guess the skin stretched a lot and now has to shrink back to normal. She ate her breakfast happily (bute less so - I got a protest of scraping of teeth on the stall wall) and went to turnout smeared with hydrocortisone creme - no flyspray on her neck as I didn't want to further irritate the skin, although I think the creme will scare off the flies.
This afternoon, the swelling was largely gone, although now the whole area on the side of her neck - most of her neck down to her shoulder and then extending down to her chest - was pleated, and there were two small areas where the skin was gone, just at the front of her chest and in the area along her shoulder blade where the pleating had been this morning. I didn't do the hot packs, as the swelling was mostly gone and it was just too hot. I tried putting the baking soda paste on, but she objected violently - it clearly hurt - so I stopped and hosed it off. I put more hydrocortisone creme on the whole large area, and put Swat around the edges to try to keep the flies off. One of the possible complications of cellulitis is sloughing of the skin - I hope this doesn't happen as it's a large area and managing that size of open wound at our barn may be difficult. She was comfortable again after I was done and started eating her hay. I'll see how she is in the morning, and probably call the vet to get some advice - hoping a visit to the vet clinic doesn't end up being required.