Having raised birds growing up with my mother and banding my first at my own home in 1982, I have never had this problem before.
Chicks look pale and lethargic and do not seem to beg to be fed. A couple of weeks ago I notice these symptoms and since the mother was not a good feeder, I blamed her for losing her chicks. Then a nest of four banded fully feathered chicks look fine one day and the next two were dead. Then another nest and each time I would hand feed the chicks and they would die. I tried different hand feeding formulas knowing about the Exact recall, I had lots of theories but nothing worked. Overall, few nest were effected.
A couple of days ago, I started itching and finding small red spots on my upper body. Immediately I accused my family of using too much laundry soap and was sure I was allergic to it. I took extra showers and benadryl and the spots would disappear only to reappear later. I demanded that all my clothes be rewashed with no soap! My daughter who normally washes my clothes was sceptical. Why now she asked, nothing has changed? I explained it takes time to develop these things.
Then today, the lovely nest of two Staffords and one fostered border which I posted last was in trouble the non-crested Stafford chick and the border chick were dead. At that point, I finally saw mites! I suspected mites but couldn't find them. I should have taken action when the first nest had the problem...
I jumped in the car and ran to Lowe's and bought Hot Shot pest strips and Sevin dust. I hung the pest strip and dusted between the nest pad and the nest with Sevin dust. All non-breeding birds are going to get a dose of ivermectin in the water today after I finish the post.
Looks like breeding season is going to be over. I do have the three nests which are only a couple days old and I will let any setting set but this will probably finish me off. Hope I do not lose anymore chicks.
Talked to a friend, a long time breeder who had this problem for the first time this year and he said that someone he knew went to the Doctor twice before figuring out that his red spots were the aviary mites too.
Another interesting observation is that the nest that developed the problems were only those not getting KD powder in the water or in the case of the stafford and border nest, I had just taken them off it the day before. I normally use KD in the water after all eggs hatch but have not when another hen is sitting on eggs in the same cage. This time I had stopped the KD, to give some vitamins in the water and the problem showed up immediately, even by evening I noticed the chicks not begging; Hind site is always better....Just makes me sick!!