Research Progress Report 345 Project 1295 August, 1968

Comparison of Winter Gains of Weanling Replacement Heifers With and Without Vitamin ADE Injection*
K. J. Drewry, Randall Peterson, Jr., C. J. Kaiser,
C. J. Callahan, L. A. Nelson and T. W. Perry,
Departments of Animal Sciences,
Veterinary Clinics: and Southern Indiana Forage Farm

Introduction
Vitamins may be defined as organic chemical compounds required in very small amounts and functioning as "accessory nutritional factors" in normal physiological development and maintenance of animals. A deficiency of any one vitamin may seriously affect normal body function.

Vitamins A, D and E are fat-soluble vitamins and are not synthesized by the animal. The B-complex vitamins (water soluble group) are required by beef cattle; however, these vitamins are normally synthesized in sufficient quantities by rumen bacteria.

The chief function of Vitamin A is to maintain health of soft, moist tissues such as the mucous membranes of the respiratory system. Thus, Vitamin A aids in prevention of many respiratory ailments.

One of the first symptoms of Vitamin A deficiency is the inability to see well in poor light. Secondary deficiency symptoms may be: depressed rate of gain, lowered resist-
ance to stress, swelling of brisket and legs (edema), depressed appetite and poor muscular coordination. Vitamin A deficiency is most likely to occur during late winter months especially if a poor quality forage is fed or with high concentrate feeding.

VitaminD is second to Vitamin A in importance. Vitamin D is essential for the proper use of calcium and phosphorus in developing sound bones and teeth, and is very important in young, growing animals. Rickets, a malfunction in proper use of calcium and phosphorus, can be prevented by Vitamin D supplementation. Symptoms of rickets are swollen joints, arched backs, bent knees, stiffness, poor appetites and depressed weight gains.

The most common sources of Vitamin D for beef cattle is sunlight. Action of ultra violet light in sunshine converts the substance 7-dehydro cholesterol, found in the skin of all animals, into Vitamin D. Another source of Vitamin D is sun-cured roughages. Bleached or poor quality hay may contain as much and in some case more Vitamin D as high quality hay with good green color.

* Injectable Vitamin A, D and E contributed by Hoffman-LaRoche Inc., Nutley, N. J.

PURDUE UNIVERSITY • Agricultural Experiment Station • Lafayette, Indiana