Lame left hind + febrile

Anybody know what this is? My 6yo Tb mare presented with acute onset non weight bearing lameness on left hindleg and was febrile (T 103C). No history of trauma or foreign body penetration. Skin was completely intact but left hindleg was swollen from fetlock to mid cannon. Tx Flunixin i/v and Ceftiofur i/m. No improvement for 4 days. Day 4 serum started to ooze from the swollen tissues eventually bursting out mid cannon as in pic. Temp returned to 100C. Now day 7 and serum still flowing out and has burst out medially. Still giving Ceftiofur but have no idea what it is. Virus?? This is the 3rd horse that this has happened to. Ist was· back in August and resolved but took about 2 months. Was worse. 2nd was mid Feb and still has wound on hindleg and a swollen knee which hasn't burst out yet. Have asked loads of peeps but no body has seen anything like it. I llive in Ireland

I don't see a pic…but what you are describing sounds a lot like cellulitis.

Some sort of toxic weed? There are a few we have locally that will cause fever and stocking up.

Yes I agree its a cellulitis but its proving very difficult to find the cause. I have pictures but not too sure how to upload them? I don't think the cause is a toxic weed as 2 of the horses were housed

Certainly sounds like cellulitis to me. I would strongly recommend having your vet prescribe antibiotics as it can turn septic.
They don't need a cut to get cellulitis, it can come from a tiny scratch in which bacteria has entered the system, it can come from standing around in mud all day, it can come from infection elsewhere in the body etc.
One of my horses got it from a joint infection in his hock, after the vet nerve blocked him without shaving and disinfecting the area first. Needless to say I never returned to that vet.

Kayty, Ceftiofur is an antibiotic, but I think in this case, the wrong one.

Kate82, here are my thoughts on your treatment

1. I like the Flunixin (which I believe is generic Banamine - and you can give injectable Banamine orally which is easier than IV)

2. Ceftiofur doesn't seem to be working like it should, so I think you need a change here. Talk to your vet about switching from Ceftiofur to Bactrim or some other SMZ/TMP that covers both staph (which I think is your problem) and strep.

3. Cold hosing and hand walking might help as well.

That said, I am NOT a vet, just a horse person who has been around the block a time or two.

At any rate, good luck and keep us posted on how things turn out.

Sorry, I am not aware of the antibiotics used o/s, I'm in Aus.

HorsePoor thanks for your post. Ceftiofur is effective against Gram positive and Gram negative bacteria including Staph. She was on antibiotics for 8days and it is doing well. We have about 20 horses and i'll love to know whats causing it because I don't want anymore to get it!!!

You may well never discover root cause because it is just when an infection has entered.

Could be a tiny patch of mud fever or just a little cut or scratch.

If it's persistent then its asviseable to get a swab and identify the bacteria and target with appropriate antibiotics.

Once a horse has had celulitis it can before prone in future if the lymphatic system has been affected.

Agreed, but Ceftiofur is a cephalosporin and is ineffective for MRSA (methicillin resistant Staph aureus).

Glad she is doing better!