In the beef cattle diet, common roughages include hay, silage and grass. Silage is a crop that has been preserved in a moist, succulent condition by partial fermentation in a tight container (silo) above or below ground. The majority of the food cattle eat comes from this type of feedstuffs.
Birds (some dinosaurs) and mammals have a four-chambered heart. The ventricle is divided by a septum into two compartments completely separating oxygenated from deoxygenated blood and delivering the maximum amount of oxygen to the head and body at the most efficient pressure.
The Heart and Its Electrical System. The Heart and Its Electrical System. The heart has four chambers. The two upper chambers are called atria (the right atrium and the left atrium), and the two lower chambers are called ventricles. Normally, the heartbeat starts in the right atrium in a group of special heart cells called the sinoatrial (or sinus) node.