Document Type

Thesis - Open Access

Award Date


Degree Name

Master of Science (MS)

Department / School

Animal Science


An experiment consisting of three separate trials was conducted to determine the effect of adding erythromycin thiocyanate at various levels to growing-finishing swine rations. The study was concerned with the effect of the antibiotic on feed palatability, feed consumption, rate of gain, feed efficiency, and fecal bacteria when added to various rations fed to growing-finishing swine. It was concluded that erythromycin stimulated gains and improved feed efficiency when added to protein supplements at 25 grams per ton even though it decreased the acceptability of the supplement initially. When erythromycin was added to the supplement at 50 grams per ton palatability was affected resulting in decreased gain, particularly during the first few weeks when the gain is mostly growth. The addition of erythromycin to complete mixed rations or to ground corn at 25 and 50 grams per ton stimulated gains slightly. When 25 or 50 grams or erythromycin or 25 grams of chlortetracycline were added per ton of complete mixed ration for 100 pound pigs daily gain, fecal coliform counts and feed efficiency were increased.

Library of Congress Subject Headings

Swine -- Feeding and feeds
Antibiotics in animal nutition


Includes bibliographical references



Number of Pages