Another Daft Q or 2...Learning More Every Day!!

A Polish bantam may have problems making the right, er, connections with your LF Orps!    However where there is a will there is a way 

Having said that the breeds are so disparate that I would probably want to prevent it from happening - even with with Wellie, Sussex and speckledy - or at least not incubate any of the eggs.

Think about it from a practical point of view - what would such a breeding bring to the offspring?

You can tell if an egg is fertile by cracking it open and looking for an enlarged blastoderm (germ cell) on the yolk.  In an unfertile egg it is small and irregular.  In a fertile egg it is round and looks like a bullseye.

Obviously you can't incubate a cracked egg lol, but if one egg is fertile, then there is a high probability that others (from the same hen) are too.

I'd agree with Casey I don't think these crosses make much, if any, sense at all.  I'd suggest you stick to a pure breed mating or at least a L/F pure breed cross.  A cross between a bantam polish cock and one of the L/F breeds you name would have some odd characteristics I'd think.  Don't forget you'll get cocks and hopefully hen offspring.  The cocks will be useless and will need to be culled.  The Speckledy is a hybrid hen and therefore useless to breed from in any case.

HF

I used one of my Marans eggs this weekend, and was amazed to find it fertile!  My Marans girl is pretty hefty, and my cockerel is a tiny Sabelpoot... I don't even want to think of the mechanics lol!

After cracking todays 6 eggs ready for scrambling i found 2 of them fertilised which surprised me after the 'connection' post...i have to agree with your last post Hillfooter