Answer to Question #248113 in Human Anatomy and Physiology for Veee

Question

Explain why avian species are more prone to respiratory diseases than other animals

Answer 1

Increased food intake results in large depositions of body fat, molt of feathers, migration, and reproduction are all physiological and behavioral events that avian species, particularly migratory birds inhabiting the temperate zone of North America, Europe, or Asia, exhibit throughout their annual cycles. Each of the events takes place in a logical and predictable order and needs a significant quantity of energy.

The avian respiratory system is extremely efficient, yet it is also quite sensitive to diseases. When compared to mammals, the avian respiratory tract is significantly different and far more efficient. An wide infraorbital sinus, a choana, and a larynx without an epiglottis distinguish the upper respiratory tract of birds. The lower respiratory tract's air movement is complicated, involving movement between several air sacs and the lungs. Fresh oxygenated air is pushed via the parabronchi of the lungs, the location of gas exchange, during both inspiration and expiration. This particular process improves the efficiency of the avian respiratory system, but it also makes birds more vulnerable to airborne contaminants. 

Most nasal secretions drain directly into the oral cavity and are ingested due to the presence of the choana. As a result, compared to mammals, nasal discharge and sneezing are less common in birds with upper respiratory tract (URT) disorders. In birds with URT disease, crusting around the nares, mucoid discharge, or cellular debris collected in the choanal slit may be present. Periorbital puffiness is a typical symptom in birds with infraorbital sinus infections.