Septicaemia is a systemic response to the presence of bacteria and/or their toxins in the blood stream.
This can be either from a single or multiple source of infection in a variety of body organs and in response to a wide range of bacterial infections.
The response to the bacteria or toxins is meant to be protective but can be as harmful as the presence of the bacteria or toxins themselves.
Septicaemic calves generally present as lethargic and depressed and may have an elevated temperature and show signs of multi organ involvement including joints and the respiratory tract.
Common causes include diarrhoea and acidosis but other bacterial infections including meningitis are possible. Calves usually show signs of septicaemia within the first week of life.