Iodine absorption, excretion, recycling, and tissue distribution in the dairy cow. [/sup 131/I tracer technique]

Journal Article · Wed Oct 01 04:00:00 EDT 1975 · J. Dairy Sci.; (United States)

DOI:https://doi.org/10.3168/jds.S0022-0302(75)84753-9· OSTI ID:7299572

Miller, J K; Swanson, E W; Spalding, G E

Research on iodine metabolism was reviewed with special reference to cattle and milk secretion. Iodine metabolism in the fetus and thyroid activity as related to milk secretion and iodine feeding have also been considered. Between 70 and 90 percent of dietary iodine is absorbed directly from the bovine rumen, reticulum, and omasum. In the abomasum, rate of iodide secretion is approximately 18 times the rate of absorption. Circulating thyroxine is not secreted into the abomasum but enters the small intestine in the bile. Most of the iodide secreted into the abomasum is reabsorbed from the small and large intestines; absorption of thyroxine averages less than 10 percent. The thyroid usually contains an amount of iodine equal to the daily dietary intake; extrathyroidal tissues concentrate only .006 to .04 percent as much radioiodine per unit weight as the thyroid. At normal iodine intake (<10 ..mu..g/kg body weight daily), iodine losses average 30 percent of the daily intake in feces, 40 percent in urine, and 8 percent in milk. Milk iodine is influenced by amount and chemical form of dietary iodine, stage of lactation or milk yield, seasonal effects, goitrogens, and thyroid status. Cows secrete less iodine into milk than most other species and have an efficient iodine recycling system via the gastrointestinal tract which conserves iodine and can protect them against low dietary iodine. (auth)

• Research Organization: Comparative Animal Research Lab., Oak Ridge, TN
• OSTI ID: 7299572
• Journal Information: J. Dairy Sci.; (United States), Journal Name: J. Dairy Sci.; (United States) Vol. 58:10; ISSN JDSCA
• Country of Publication: United States
• Language: English

Related Subjects

550501* -- Metabolism-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
ANIMALS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BODY
BODY FLUIDS
CARBOXYLIC ACIDS
CATTLE
CLEARANCE
DAYS LIVING RADIOISOTOPES
DIGESTIVE SYSTEM
DISTRIBUTION
DOMESTIC ANIMALS
ELEMENTS
ENDOCRINE GLANDS
EXCRETION
FOOD
GASTROINTESTINAL TRACT
GLANDS
HALOGENS
HORMONES
INTERMEDIATE MASS NUCLEI
INTESTINAL ABSORPTION
IODINE
IODINE 131
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
MAMMALS
METABOLISM
MILK
NONMETALS
NUCLEI
ODD-EVEN NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
ORGANS
PEPTIDE HORMONES
RADIOISOTOPES
RUMINANTS
SECRETION
THYROID
THYROID HORMONES
THYROXINE
TISSUE DISTRIBUTION
TRACER TECHNIQUES
UPTAKE
VERTEBRATES