A sheep has so much fat around it's heart to protect the valves in  the heart. There is also a lot of fat there to maintain the body  temperature of the heart.
Definition and Causes. Upper respiratory tract infection (URI) is a nonspecific term used to describe acute infections involving the nose, paranasal sinuses, pharynx, larynx, trachea, and bronchi.The prototype is the illness known as the common cold, which is discussed here, in addition to pharyngitis, sinusitis, and tracheobronchitis.efinition and Causes. Upper respiratory tract infection (URI) is a nonspecific term used to describe acute infections involving the nose, paranasal sinuses, pharynx, larynx, trachea, and bronchi.
Medical Definition of Upper respiratory infection Our Upper Respiratory Tract Infection Main Article provides a comprehensive look at the who, what, when and how of Upper Respiratory Tract Infection Upper respiratory infection: An infection of the upper part of the respiratory system which is above the lungs. An upper respiratory infection can be due to any number of viral or bacterial infections. These infections may affect the throat (pharyngitis), nasopharynx (nasopharyngitis), sinuses (sinusitis), larynx , trachea (tracheitis) or bronchi (bronchitis). Upper respiratory infection is commonly abbreviated URI.