Bacillary Haemoglobinuria
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| Also known as: | Red Water Clostridium novyi Type D |
Description
A disease of cattle and sheep caused by Clostridium haemolyticum which is a bacteria from the class Clostridia. C. haemolyticum is found in soil, poorly drained/wet pastures and is highly fatal to livestock. The bacteria produces a beta toxin which causes hepatic necrosis and intravascular haemolysis. The disease is often associated with a disease in the liver that causes anaerobic conditions allowing the growth of bacteria and hence toxin production. The damage to the liver is frequently caused by liver fluke.
Signalment
Cattle are the most commonly affected animal but sheep can also be infected. Animals in better body condition seem to be more susceptible to disease.
Diagnosis
Often clinical signs are enough to make a presumptive diagnosis. Additionally urine can be collected and either left to settle or centrifued. This will confirm the presence of haemolysis rather than frank blood in the urine where the red cells will settle at the bottom.
A definitive diagnosis can be made by isolating C.haemolyticum from the liver however it can be difficult to culture. Additionally the organism can be confirmed on fluorescent antibody or immunohistochemical testing of liver tissue.
Clinical Signs
Animals can be found dead often in lateral recumbency, bloat and little signs of struggle with blood in the nostrils, mouth, rectum and vagina. If animals are seen alive, the most obvious sign is a port wine coloured urine that froths on voiding. Animals are also often depressed, reluctant to move, pyrexic, have pale mucous membranes and are jaundice and sometimes in respiratory distress.
Pathology
post mortem findings include rapid decomposition of the carcass, organs are also decomposed with subcutaneous hameorrhages, odema and emphysema present. Abdominal and thoracic fluid are blood stained and a large quantity will be in the pericardium. The animal is severely anaemic and may be jaundiced. Red urine in the bladder, and the kidneys will be speckled with haemoglobin. There is usually a single large necrotic focus in the liver that is sometimes partially liquefied in the centre, and an irregular outline with a hyperaemic edge. Microscopically, fluorescent antibody testing can identify the organism. The presence of Clostridia post mortem must be interpreted with great caution as they are common post mortem invaders.
Treatment
It is unlikely that cases are recognised early enough for treatment to be effective. Very high doses of penicillin or oxytetracycline can be used and animals often need a blood transfusion if possible.
Prevention
Vaccination is available and lasts for up to 6 months. Liver fluke control should also be instituted to prevent any damage to the liver. Infected carcasses should be removed from pasture as spores can survive for up to NB: Distinguish Red Water from Black Disease! The former will have bleeding out of any orifice while the latter does not