We describe Dirofilaria immitis occurring in the peritoneal cavity of a dog from Korea. Two worms were found in the fat of the umbrical cord area during operation for an umbrical cord hernia in a dog (four year old, female, Maltese). In gross findings, the worms were slander white and measured 132 mm (female), 111 mm (male). The tail of the male was spirally coiled. In light microscopy, the uterus was filled with not fully developed eggs. Scanning electron microscopy revealed that the cuticule was smooth on the head but those of the tail exhibited complex cuticular striation in the male. Head papillae were located in a cephalic plate forming a rectangular pattern dorsoventrally, with 4 inner labial papillae and four outer cephalic papillae. The mouth opening was very small and the bursal cavity was absent. Laterally there was a pair of amphids.
Case report of an internal granuloma investigated by light and scanning electron microscopy