Variability in the ratio between the numbers of microfilariae and adult heartworms.
D000818:Animals; D001769:Blood / Q000469:parasitology; D004183:Dirofilaria immitis; D004184:Dirofilariasis / Q000469:parasitology / Q000662:veterinary*; D004283:Dog Diseases / Q000469:parasitology*; D004285:Dogs; D008842:Microfilariae