I have about 20 dorset type ewes that did not breed for some reason last winter and I was wondering if anybody has tried using hormones or the CIDR sponges to get them into heat.  These ones did breed last year, were flushed during breeding and nothing.  I want to move to January lambing anyway.  My Cheviot ram bred all my cheviot ewes but not these ones for some reason. 

Thanks, Dan