I’ve never heard of chocolate dilution (b/b) being linked to infertility in any breed. Although, dilutes are undesirable in some breeds, because the genes affect pigment too and are sometimes associated with alopecia. Well, at least, blue dilution (d/d) is connected to the skin/coat issues. The closest thing I can think of related to infertility is the merle gene, which causes dilution in random areas. When homozygous it results in hearing, vision and possibly infertility problems. However, the merle gene has nothing to do with chocolate dilution. I would get more information from Havanese breeders. Breed standards, genetics and breeding are not a typical veterinarian’s specialty.
Havanese Club of America:http://www.havanese.org/
Genetic Links:http://bowlingsite.mcf.com/Genetics/Colo…