this is my first winter with chickens, and, for the last few days, or temps have been below/barely reaching 30 during the day, and between 14 and 19 at night-- fairly cold for NJ. My one roo has a small area of one of his comb peaks turning black (I know that is frostbite), but my other roo started with what looked like a tiny little blister and has progressed to this (notice the big yellow blister towards the back...it is filled with puss). this roo is my baby so I started putting vaseline and 3x oint on the tips of his comb every other day as soon as I noticed the first little blister...I am assuming this is frostbite. three questions: 1) is this frostbite or something else? and 2) is this more mild or more severe frostbite than when the area turns black? annnnnd 3) any thoughts on whether vaseline or bag balm or similar product works? some people say it is actually harmful so I just want to be sure I am not making things worse.... Thanks!