Sudden deaths with few lesions could be the first sign of an infection in a group of pigs. Other symptoms include:
Redness and blotching of the skin may also be seen, especially on ears, tail, legs, and ham. Bloody diarrhea may occur, as well as abortions in pregnant sows. Strongly consider carrying a thermometer and taking temperatures of sick pigs.
If you observe these signs, contact your manager or veterinarian.