Bad Apple Branches

[Mounds]

My guinea pigs like apple wood, but they don't eat it very fast. I've had the same pack of apple wood branches from Oxbow for 3 months. Today I noticed that on one of the branches there was a powder substance on the branch I had just given to my Guinea pigs. I looked closer at the other branches and noticed that the others had it to, mostly in the little notches on the sticks. I've kept the branches in a dry, non-humid environment, and they have not had any contact with water, so I thought they would remain relatively shelf stable. I'm going to ask our vet tomorrow morning as well as keeping an eye on them tonight. Is there anything I should do until then? Is this mold? I am really worried. I included some photos of the branches, but it is kinda hard to see in them.

 

[Mounds]

Update: So far they all are doing ok and when I asked the vet he said that if we weren't seeing anything by now they should be ok.

I would still like to know what it was on the branches, because it didn't look like mold exactly and when I tried looking it up there is apparently this disease called powdery mildew that can be on apple branches (caused by the Podosphaera leucotricha fungus, but I couldn't find what happens when ingested because the only things I could find where the etiology and treatment for apple trees), but it doesn't look the same. And if it was mold how could the branches mold if I kept them in a dry environment, and they never got wet. I don't know if I did something wrong in the storing of them, if I order a bad batch, if this is just what happens with apple branches, or even if I'm freaking out for no reason.... in general I'm just pretty confused right now.

 

[Swissgreys]

Firstly I don't think you need to panic.
Sometimes products aren't stored well (prior to sale) and might have issues, but it is unlikely affect your piggies.
Just throw the branches away if you are unsure.

 

[Mounds]

ok thank you