Occasionally a calf develops infection in which bacteria or their toxins get into the bloodstream and travel throughout the body, creating a condition called septicemia. Some toxin-forming bacteria rapidly cause death.
The calf goes into shock when internal organs are damaged and start shutting down, and in some instances the infection may localize, creating internal abscesses, or may settle in the joints —causing a painful arthritis (“joint ill"). “Endotoxemia caused by clostridial bacterial (such as C. perfringens) is not a true septicemia, in this instance it‟s just the toxins of the bacteria getting into the blood.
Septicemia can be a common sequel to many types of scours, however, such as infections with E. coli or salmonellae. The salmonellae are highly pathogenic and invasive, and tend to go septicemic more than some other types of scours,"
A septic infection may originate via the navel stump in a newborn calf, or from ingested pathogens via the digestive tract, or the lungs (pneumonia that progresses into septicemia). Calves with adequate passive transfer of immunity (antibodies from the dam‟s colostrum) are less likely to develop septicemia than calves who don‟t ingest adequate colostrum in a timely manner.