another question about ISA Browns

[poupoule]

Hi guys,

I have 2 ISA Browns, 1 Leghorn (not sure of the spelling) and a Red IslandxAustralorp rooster (I think). I also have in a differnt coop a bantam and 2 silkies. The bantan sat on some eggs (some of hers and some of my big breed) and 3 (out of 10 )chicks hatched (2 weeks old now

), but none of the big breed. One of my silkie also strated to sit on some eggs (mix again) but after candling them all the ISA Brown eggs were not fertile.
So here are my questions. Can you actually breed ISA Browns with other breeds? Or is it my rooster's fault? The rooster was given to me last year. Do they stop being fertile or low in sperm when they get old? Would it be time for me to replace him, or is it the ISA Browns fault? I love their egg production but would like to increase my flock, especially my big breed whhich produce decent size eggs. Can anybody out there help? Thanks

 

[RAREROO]

Do ou know how old your roo is? I have heard they do get infertile with age.

 

[poupoule]

No I have no idea how old he is, but the egg from the Leghorn hen is fertile and she is with him and the ISA Browns.