title: Salt and water excretion by birds: the lower intestine as an integrator of renal and intestinal excretion.
abstract: 1. In the fowl, the small intestine is important for net absorption of Ca2+ and K+, but not for Na+ nor water (in this and several other species). 2. Net water absorption in birds with large saccate caeca occurs in caeca greater than rectum greater than coprodeum, but net Na+ absorption (an active process motivating other absorptive functions) occurs in rectum less than caeca and coprodeum. 3. Interspecific variability and the scarcity of comparative studies militate against broad, well-founded generalisations in this subject.
mesh_terms: D000818:Animals; D001717:Birds / Q000378:metabolism* / Q000502:physiology; D001834:Body Water / Q000378:metabolism*; D002118:Calcium / Q000378:metabolism; D002432:Cecum / Q000502:physiology; D002988:Cloaca / Q000378:metabolism* / Q000502:physiology; D007413:Intestinal Mucosa / Q000378:metabolism*; D007421:Intestine, Small / Q000378:metabolism; D007668:Kidney / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D012007:Rectum / Q000502:physiology; D012964:Sodium / Q000378:metabolism; D012965:Sodium Chloride / Q000378:metabolism*; D013045:Species Specificity
chemical_list: D012965:Sodium Chloride; D012964:Sodium; D011188:Potassium; D002118:Calcium