Quote:
Originally Posted by pstinard  From the abstract of that paper (which has phenomenally large sample sizes):
"In all breeds, the overall proportion of the bitches that developed disease by 10 years of age was for pyometra 19%, MTs 13%, and either or both of two diseases 30%"
A 30 percent chance of developing pyometra or mammary tumors in unspayed dogs seems like an awfully high risk to take, unless there are factors that counterbalance the risk. The abstract doesn't give the data for Yorkies, but if the rate is anywhere near 30%, that seems like a strong argument for spaying before first heat. If I have time, I'll try to check out the full text of this article on Monday and I'll let you know if it has data specific to Yorkies. |
I forgot to mention that the study includes data for 110 breeds of dogs for which there were more than 1,000 dog years at risk of data per breed. (Each year a dog was insured contributed to one dog-year at risk). The study included 1,959 female Yorkies, which is a very large number. Yorkies were ranked the 61st most at-risk breed for pyometra (which is mid-range for all breeds studied), 24th most at risk for mammary tumors (which is in the top quartile), and 36th most at risk for developing one or the other (high second quartile). IMHO, based on these data, the rate of pyometra for unspayed Yorkies (21%), the rate of mammary tumors (25%), and the rate of one or the other (39%) provide a compelling reason to spay Yorkies before the first heat, UNLESS they are being used as breeding stock, or have a health issue that would make the risk of spaying too great for a particular individual.