frostbite comb question

[ZuniBee]

Someone in the thread observed that high humidity level in the coop in freezing/subfreezing weather was the main culprit. I installed an indoor/outdoor recording weather gauge in the coop. The results led to my getting serious with creating adequate venting of the coop. We have had no further problems with frostbite (just finished up a run of 0° b.s.).

This is very interesting. I have been spending a lot of time wondering why my birds are getting frostbite when other folks don't have the problem and say they don't use any heat source and their temps are much lower. I have been using heat lamps every time the temp gets below freezing. I'm going to get an indoor/outdoor recording weather gauge in the coop and see what the humidity is. Thanks for this info.​

 

[ivan3]

Manual of Naval Preventive Medicine
NAVMED P-5010
010-LP-207-1300

9-38. Environmental Factors.

2. Humidity. Cold injury is due, in part, to the effect of low temperatures on moisture in or on the body. The higher the moisture content, especially on the skin surface, the more rapid the heat loss. As humidity rises, the temperature at which cold injury can occur also rises. High humidity can also induce sweating which will further reduce body heat.

3. Wind velocity. Heat loss is further influenced by wind velocity when humidity is high.

Just thought I'd post this as well. Our coop dimensions are such that we have ~275 Cubic Feet. We use a heated dog water bowl and have 9 chooks. The coop is well sealed. During the first winter we used a 125w heat lamp. The roo started developing discoloration of his comb points when the coop temp was just below freezing (25°-30°). The relative humidity in the coop was running at ~90%!.

After constructing adjustable high/low vents on east side of coop we were able to drop the relative humidity to that of the surrounding air. This has also allowed us to still keep a 25w light in the coop on a timer so they can move around at 05:00 (just before dawn usually highest humidity level) without a jump in the coop humidity. Yes, we hear `em whining and moaning on the baby monitor when the temp bottoms out - but no frostbite.

Good luck!​