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Respiration
The ostrich is a regulator and maintains a body temperature of 38.1- 39.7 degrees in extreme temperature conditions, such as, the heat of the savanna and desert regions of Africa .The ostrich utilizes its respiratory system as a means of heat dissipation through panting. Ostriches when panting have a respiratory rate of 40-60 cycles/min, which is 5x that of their resting rate of 6-12 cycles/min. Unlike other birds, the Ostrich is able to pant without experiencing respiratory alkalosis by modifying ventilation of the respiratory medium.

The respiratory medium, of which the ostrich obtains oxygen from, is hot, dry and lacking in moisture. Inhalation begins at the mouth, as well as, the nostrils located at the front of the beak. The air then flows through the anatomical dead space of a highly vascular trachea (~ 78cm) and expansive bronchial system, where it will be further conducted to the posterior air sacs. The Ostrich air sacs are capacious and increase the surface area for respiration. The oxygen rich air flows unidirectional across the respiratory surface of the lungs; this provides the blood that has a crosscurrent flow with a high concentration of oxygen. The blood – gas barrier of the lung tissue is thick. The advantage of this thick barrier may be protection from damage by large volumes of blood flow in times of activity, like running. To compensate for the large “dead” space the Ostrich has a large tidal volume reaching a maximum of 15L. Oxygen poor air flows to the anterior air sacs for exhalation. In all Ostrich respiration can be thought of as a high velocity low pressure system.

Osmoregulation
The coprodeum is located ventral to the terminal rectum and urodeum (where the ureters open). Found between the terminal rectum and coprodeum is a strong sphincter. The corprodeum and cloaca are the main osmoregulatory mechanisms used for the regulation and reabsorption of ions and water, or net water conservation. As expected due to the Ostrich’s moisture lacking habitat, dehydration causes a reduction in faecal water, or dry feces. This reduction is believed to be caused by high levels of plasma aldosterone, aldosterone leads to the rectal absorption of sodium and water. Also expected is the production of hyperosmotic urine; cloacal urine has been found to be more than 500 mOsm.The U:P (urine:plasma) ratio of the ostrich is therefore greater than one. Diffusion of water to the corprodeum (where urine is stored) from plasma across the epithelium is voided. This voided is believed to be caused by the thick mucosal layering of the corprodeum.