Published online by Cambridge University Press: 09 March 2007
1. Studies were performed with female rats to examine the effect of various levels of orally administered oxytetracycline on body-weight, weight of various portions of the intestinal tract, weight of mesenteric lymph nodes, distribution pattern of the tissue elements in the terminal portion of the ileum, and on the susceptibility to invasion by Salmonella typhi-murium.
2. There was no growth promotion resulting from any antibiotic treatment. A consistent finding was the decrease in the wet weight of mesenteric lymph nodes in the rats given antibiotic.
3. In the bacteriological test, no differences between antibiotic-fed and control groups were observed in isolations from the liver, spleen or intestinal tissue. It was concluded that there were no effects of oxytetracycline administration on invasive capacity of orally administered S. typhi-murium.