Hi, I'm Dr. Bonk. I'm sorry to hear about your piglet. The most important concept of wound care is cleanliness which isn't always easy with our outdoor animals. The best way to clean a dirty wound is to rinse with warm water. You may also flush the wound with a dilute betadyne or chlorohexadine solution. If there are any pockets under the skin around the edges, these will have to be flushed out 2-3 times a day to prevent an abscess.
If the skin around the edges is dark purple/black in color, it will most likely die and be sloughed. Be aware if this is the case, the wound will look worse before it looks better.
Vetricyn is a wonderful spray that can be used on all types of abrasions in all animals. It can even be used in the eyes and ears so it is a must-have for any animal owners. Most feed stores will carry it, as well as veterinary clinics. It can be sprayed on the wound 3-4 times daily.
If the wound becomes excessively red and painful, has an odorous discharge, or the piglet stops eating and becomes listless, antibiotics are needed. Piglets respond well to penicillin, tetracycline, and sulfa drugs.
I hope this helps, please let me know if you have any further questions. Thank you and good luck!