Snotty noses

Question
I use to rescue pot bellied pigs, and have a total of 9 pot bellies.  
The other day my husband mentioned that one of them had a seriously snotty nose all day.  I went and checked h out and he did indeed looked like he had thick white snot running out of his nose. I didn't think to much about it, we live in NW Michigan it's been a hard cold winter... And I figured once the nice weather got here he would get out of the barn and lay in the sun and it would clear up.
Well, just got home from work was out saying hello to them all and now a second pig now has the same snotty nose.  So now I'm concerned that there is some infection going around?
All of my pigs except 1 are around 10 years old (both of these boys are approx 10)

To the best of my knowledge they are not running a fever and they are drinking and eating as normal?

Any advice would be appreciated

Answer
I am not a veterinarian and can not make a medical diagnosis or prescribe treatment over the internet.

There's three main causes for piggy snotty noses. Illness, allergies, and foreign material.

It's very possible that piggy #1 picked up a cold and passed it along to piggy 32. If that's so, it will probably pass along through your herd. It may or may not be a germ that can jump to humans, but ordinary precautions should be enough to keep an illness at bay.

Pigs can and do develop allergies. Like in people, the two biggest causes are dust and pollen. Both are prevalent in spring and fall. Runny eyes and excessive sneezing are also signs of allergies. Sensitivity seems to be hereditary, so if this is the problem, chances are only related pigs would be affected.

Pigs stick their noses into everything, and often they inhale things they shouldn't If the piggies inhaled something they should not have, their noses will pump out snot to wash away the foreign material. Only the pigs inhaling the material will be affected. And, if the pig goes back and snurdles up more, it will look like the snotty nose has returned.

The critical signs are eating, drinking, peeing, pooping and no lethargy. If piggy is doing all the normal things, normally, piggy will most likely be ok

Nasal cancer is frighteningly common in older pigs, in part, because of how they snort things up those noses. A chronic runny or snotty nose, coughing, choking while eating or shortness of breath can signal an oral, nasal or lung/esophagus cancer.