Fore sure humidity has something to do with Balls developing a IR. Our first two years in our new building we had some females get IR and we just couldn't figure it out until we took a look at our relative humidity. We were down in the low 20% range. We since have fixed that problem and we have a small percentage of IR that we had the first two seasons. There are many other things to consider as well, stress, temps, husbandry, etc... But humidity is one for sure. Hope this helps, Brian(BHB)

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