710
WARD, JOHNSON, AND STEWART
SUMMARY
The "Cs deposited on forage from rainfall varied from about
80% on pasture plants collected shortly after a rain to a low of about
10% for alfalfa hay harvested late in the summer. Rainfall intensity
appears to be an important factor in the deposition coefficient.
About 0.33% of the “"’Cs intake in feed is secreted perliter of
milk by cows fed a commonration. However, this percentage is related
to the crude-fiber content of the ration and increases by a factor of
2 if the diet is low in crude fiber as in the case where cowsare fed
large amounts of grain.
REFERENCES
1. J. Z. Holland, Distribution and Physical—Chemical Nature of Fallout, Fed-
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2. Federal Radiation Council, Estimates and Evaluation of Fallout in the United
States from Nuclear Weapons Testing Conducted Through 1962, Report No.
4, May 1963.
3. F. Mraz and H. Patrick, Organic Factors Controlling the Excretory Pattern
of Potassium-42 and Cesium-134 in Rats, J. Nutrition, 61: 535 (1957).
4. R. H. Wasserman, C. L. Comar, and D. N. Tapper, Influence of Dietary
Potassium and Sodium on Cesium-134 Retention in Rats, Proc. Soc. Expil.
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and
Excretion of Cesium-134
and
Potassium-42 in
Grazing
Animals, Health
Lactating Dairy Cows, J. Dairy Sci., 44: 352 (1961),
6. R. J. Garner, Environmental
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Contamination
and