Bacteriology of the Liver in Normal Dogs. ∗

Abstract

The presence of organisms in the tissue of normal, healthy animals has been a controversy for some time. However, investigators have definitely proved that the tissues of normal, healthy animals harbor organisms. That the occurrence of organisms in normal tissue in the experimental animal has been a source of incorrect observation and deduction in certain experimental problems has recently been shown by Ellis and Dragstedt. 1

C. B. Hawn, 2 working with Holmes Jackson, first described a spore-bearing bacillus found in the liver of normal dogs. Walbach and Saiki 3 studied this bacillus, using 23 normal, healthy dogs, and found this gram-negative, spore-bearing bacillus in 21 of the 23 dogs. Berg, Zan, and Jobling 4 cultured the liver from 11 normal dogs and found this gram-negative, spore-bearing organism in 100% of their animals. Ellis and Dragstedt, 5 in their investigations on liver autolysis in vivo, encountered the same organism in almost 100% of their animals.

We studied the bacteriology of the contents of the stomach, the duodenum, and the liver in a series of normal, healthy dogs and the bacteriology of the stomach and the liver in 4 normal, healthy puppies, 8 days old. All specimens for culture were obtained under strict aseptic conditions. The material obtained from the animals was cultured aerobically and anaerobically in digest meat broth at 37.5°C. The positive cultures were studied by smear methods stained with gram stain after 24 and 36 hours'incubation.

The liver was cultured aerobically and anaerobically from 40 dogs. There were positive cultures in 37 dogs, negative cultures in 3. Gram-negative, spore-bearing bacillus was found in 34 of the dogs, giving a positive culture in 92.5% and the presence of a gram-negative, spore-bearing bacillus in 85% of the cases. The remaining 6 cases showed the presence of gram-positive, gram-negative bacilli and gram-positive diplococci.