I did a stupid thing just before last Christmas. I am reasonably new to this caper but I have incubated quite a few batches of chickens, ending up with roughly half girls, half boys. My husband made the comment that crocodiles hatch males at a higher temperature whereas lower temps produce females. "That should work for chickens, too," he surmised. I was toying with breeding silkies for sale and had some pre-ordered. Naturally, everyone wants girls, not boys (with the occasional exception), so I decided to lower the temperature a bit to see if I could produce more girls than boys. Looking back now, I shouldn't have experimented when I had so many orders but in my desire to have more girls, I felt I didn't want to wait. I can't remember what temperature I dropped it to, but probably over 1 degree C, perhaps closer to 2. The first chick hatched and was so cute. I watched it for the first day in the incubator as it fell over and rolled onto its back kicking its little eggs into the air until it righted itself. When it went into the brooder it kept doing the same thing but didn't appear to be doing it quite so often. I had a buyer who lived 150 kms away who was eager for 2 chicks and she didn't care if they were boys or girls so as we were driving to her to town we delivered "Rolly" to her, promising the next one as soon as it arrived. They were not hatching quickly, but seemed to have a day or two between them. But as each chick hatched, they too had no balance and they began dying after just a couple of days. I immediately removed all the eggs, keeping them warm, while I cleaned the incubator from top to bottom, and replaced the eggs. Every one of that batch died, including the one I had delivered. I agonised over why this had happened and only recently discovered that this was undoubtedly due to the low temperature. That was one experiment that was a total failure.
Shortly afterwards I set another batch of eggs - 8 of them, at just half a degree C lower than normal. One was infertile; the other 7 hatched with no problems and have all turned out to be girls. My next batch are almost all hatched - still at the half a degree lower than normal and it will be interesting to see if the first batch was just a fluke; or maybe I will be as lucky this time. I now have seven chicks that were incubator hatched; and six came from the broody hen. She hatched two then abandoned them. She had also abandoned the six other eggs so I removed them and the two chicks. I still have two eggs from the silkie in the incubator but I have a feeling that mama hen was stealing eggs from one of the other girls who insisted on laying in the same box. Time will tell with them.
So, that's the story of my experience with lower temps. Cross your fingers that I am on the right track.
