A case report of a rapid development of fetal anasarca in a canine pregnancy at term.

A 5-year-old healthy pluriparous pregnant Flat-coated Retriever bitch was monitored by ultrasound on post-ovulation days 30 and 57: no deviation from normality picture were observed. On day 60, one of the three most caudal fetuses showed ultrasonographic signs of fetal anasarca: subcutaneous edema and anechoic fluid in thoracic and abdominal cavities. There was an increased volume of extra-fetal fluids. On day 64 a Cesarean section was performed and one of the seven pups that were delivered, a female, showed generalized subcutaneous edema and died soon after birth. She weighed 660 g, compared to a mean of 472 g for the other 6 normal fetuses. A total of 295, 40 and 27.5 mL of liquid were collected from subcutaneous tissue, abdominal and thoracic cavity, respectively. Liver showed sub-glissonian necrotic areas. Molecular analyses with PCR method for canine Herpesvirus, Parvovirus, Adenovirus, Leptospira interrogans, Chlamydia spp., Neospora caninum and Toxoplasma gondii from pools of organs (spleen, kidney and brain) and pleural effusion tested negative. This is the first reported case of fetal anasarca with a rapid onset diagnosed on day 60 post-ovulation just three days after observing a normal ultrasonographic pattern in Flat-coated Retriever. Ultrasonographic diagnosis of fetal anasarca is of primary importance when assisting parturition, due to its inherent risk of dystocia. Ultrasonographic monitoring in the immediate prepartum period may be useful in all breeds as it may help to detect ultrasonographic alterations occurring right before term such as anasarca.