Canine filariasis manifestations

Canine filariasis mainly refers to canine dirofilariasis, and may also refer to canine filariasis. Adult dirofilaria mainly parasitize in the pulmonary artery and left ventricle, with clinical symptoms such as cough, decreased endurance, and weight loss. Meanwhile, canine filaria mainly parasitize in the trachea and bronchi, presenting with symptoms like cough, difficulty breathing, and loss of appetite.

Canine filariasis first considers dirofilaria infection, also known as heartworm. Adult heartworms mainly parasitize in the pulmonary artery and right ventricle. If the infection continues to worsen, adult heartworms can be found in the right atrium, anterior and posterior venae cava, and pulmonary artery. Adult heartworms are long, slender white worms, with males measuring 12-16cm. Dogs mainly become infected through mosquito and flea bites.

The clinical symptoms of heartworm infection mainly depend on the severity and duration of the infection. Main symptoms include cough, decreased endurance, and persistent weight loss. Additionally, there may be palpitations, internal heart sounds, accompanied by difficulty breathing, fever, and abdominal distension. If the disease exacerbates, severe anemia may occur, leading to gradual wasting and death. Furthermore, heartworm infection can also cause nodular skin disease. This is characterized by itchy skin and accompanied by skin ulcers. The center of the skin nodules is a purulent area, and microfilaria can usually be found in the surrounding blood vessels. Canine filaria adult worms mainly parasitize in the trachea and bronchi, and sometimes can be found in the pulmonary parenchyma.

Canine filaria male worms are slender, with a body length of 5.6-7mm. The cause of canine filariasis infection in dogs is mainly due to maternal dogs licking puppies or fecal contamination. The severity of the clinical symptoms mainly depends on the degree of infection and the number of nodules, presenting with chronic symptoms but sometimes causing death. The most obvious clinical manifestations are stubborn cough, difficulty breathing, loss of appetite, and progressive weight loss.