So far this year I haven't had a single Silkie or Cochin egg be fertile. I've incubated some three times and every couple of days I crack some to check for the bullseye. In the Cochin pen there is one rooster and six hens. The Silkie pen has two roosters and seven hens. Because of their abundant fluff I trimmed the Silkies two weeks ago to improve fertility but it has made no difference. The oldest birds are only 18 months old. What can I do? Provide candle light and soft music?