(Hinde K, et al, (2014), Holsteins Favor Heifers, Not Bulls: Biased Milk Production Programmed during Pregnancy as a Function of Fetal Sex. So, seriously, someone posted french maran chicks on craiglist and said they are 90% guaranteed to be pullets because - and I quote - "I have learned to sex the eggs and have gotten good. All logic and education tells me that an egg simply can't be sexed. " If i must choose to make a dollar or a friend , I will choose the friend every time .The dogs in my avatar pic are fat Sam, the assumed cross of a greedy black Lab and a sneaky Collie, and grumpy Meg, the smallest and narkiest Jack Russell for 50 miles in any direction.Breeder of Marsh Daisies; keeper of a pick-n-mix laying flock of Leghorns, Marans, ISA Browns, Black Rocks, Daisy culls and various Mystery Muttleys.Larger eggs do not make for roosters (and vice versa). he said the eggs that are more pointed are roosters and the more round eggs are the hens ? " JP" My mentor Home of "West Slope Seramas"" The great thing about not telling a lie . " If i must choose to make a dollar or a friend , I will choose the friend every time .In all of the candling threads and articles I have read, not once has sexing been a topic. i tryed this in the incubator and i used the pointed eggs to see if i could get all roos guess what out of ten eggs nine where cockerals so i don't know now i m trying with the smaller round eggs will see what happens ??????? " JP" My mentor Home of "West Slope Seramas"Breeder of Marsh Daisies; keeper of a pick-n-mix laying flock of Leghorns, Marans, ISA Browns, Black Rocks, Daisy culls and various Mystery Muttleys.
Hi there I'm afraid my opinion is that it's nonsense.
The theory of 'sexing' an egg defies all known theories and I wouldnt waste my money.