A female dog is usually diestrous (goes into heat typically twice per year), although some breeds typically have one or three cycles per year. The proestrus is relatively long at 5 to 9 days, while the estrus may last 4 to 13 days, with a diestrus of 60 days followed by about 90 to 150 days of anestrus. Female dogs bleed during estrus, which usually lasts from 7–13 days, depending on the size and maturity of the dog. Ovulation occurs 24–48 hours after the luteinizing hormone peak, which is about somewhere around the fourth day of estrus; therefore, this is the best time to begin breeding. Proestrus bleeding in dogs is common and is believed to be caused by diapedesis of red blood cells from the blood vessels due to the increase of the estradiol-17β hormone . 
Common misspellings: criptorchidism, criptorchid, cryptorkidism, cryptorkid, criptorkidism, criptorkid,cryptorkydism,cryptorkyd, criptorkydism, criptorkyd, cryptorchydism, cryptorchyd, criptorchydism, criptorchyd,testical, testecal, testacal, testucal, testecle, testacle, testucle, nuter, nutered, nutering.
Alternative, slang synonyms for testicles: ball, balls, nut, nuts, goolies.
Alternative, including slang, synonyms for desexing: nut, nutting, nutted, the snip, the chop, castrate, castrating, castrationing, castration, gonadectomy, sterilisation, sterilising, sterilised, sterilization, sterilizing, sterilized, neutered, neutering, neuter, fix, fixed, fixing, desex, desexing.
Some pathologists subclassify grade 2 mast cells as high grade 2 or low grade 2 mast cell tumors; high grade 2 tumors behave like grade 3 tumors and low grade 2 mast cell tumors behave like grade 1 tumors. Beware that grading mast cell tumors is very subjective. In one study, mast cell tumors were graded by a group of pathologists and they commonly disagreed upon the grade of the tumors. A much better testing method of determining the how malignant or benign a mast cell tumor will behave is a proliferative study. This includes PCNA (proliferating cell nuclear antigen), AgNOR (agyrophilc nuclear oganizing regions), and Ki67. Tyrosine kinase receptors (a receptor for mast cell growth factor) is also important and tests related to this include cKIT mutations and KIT staining patterns. All of these tests in the panel are important, however cKIT mutations are very dangerous and the Ki67 also seems to be very important. These tests are more expensive than standard testing (histopathology), but they seem to be worthwhile.