A comparison of the feeding values of red clover hays of low and average phosphorus supplement, as the roughage in the ration for growing calves

This thesis is a report of work done by The University of Tennessee Experiment Station during the year of 1941-42 with which the writer assisted.

The experiment was a continuation of work begun in 1939 to obtain information relating to the effects of feeding red clover hays of varying phosphorus contents to growing beef calves (3). Results from the first year's work indicated that when beef calves were fed rations in which hays of varied phosphorus content furnished the roughage "the animals receiving the high phosphorus red clover hay made better use of their feed, maintained a higher blood phosphorus and a thriftier condition, as evidenced by making greater gains and more growth than animals receiving the low phosphorus hay of the same species".

At the end of the first year's experiment it was thought advisable to continue the work. The objective for the second year's work was to "study the growth of calves fed rations differing only in the phosphorus content of the red clover hays” (14). Results obtained for the second year were not consistent with those for 1939. The low phosphorus hay gave consistently better results as measured by gain in weight. It was thought that this might be due to certain undesirable factors (e.g. foreign matter) in the high phosphorus hay. Also, the phosphorus content of the low phosphorus hay used during the second year contained 0.16 percent phosphorus which was considerably above that for either the first or third year.

The work was continued this past year to (A) compare the feeding value of a red clover hay of a good average phosphorus content with one of low phosphorus content, as the roughage in wintering ration for growing calves, and (B) to compare the effects of adding a liberal phosphorus supplement to rations fed for objective A.