- Jaundice is the yellowing of body tissues like gums and conjunctiva due to liver malfunction or excessive breakdown of red blood cells, leading to an accumulation of the yellow pigment (bilirubin) in the body.
- Jaundice typically results from serious liver damage, where the liver cannot process the excess bilirubin and allow its removal from the body.
- Liver malfunction can be caused by a variety of toxic plants.
- Cirrhosis occurs when liver cells are so damaged, they die and are replaced by scar tissue. Cirrhosis is a sign of chronic liver disease.
- Liver damage, producing jaundice and cirrhosis, also results in reduced growth rate/weight loss, death, and extra costs due to management/treatment.
- Jaundiced animals can be prone to sunburn. This is because the liver also processes the light-sensitive chemical chlorophyll that plants use to capture sunlight; a damaged liver may not remove all active chlorophyll from the circulation thereby leaving the skin hypersensitive to sunlight.
- At the abattoir severely affected (yellow) carcases or livers may be condemned.
- Various toxins cause liver damage resulting in jaundice and/or
- Mycotoxins produced by fungus and commonly found in lupins (Lupinosis) and spoiled or mouldy feed (Aflatoxicosis).
- A variety of toxic plants (e.g. Lantana, St John’s Wort) can cause liver damage, jaundice and light sensitivity.
- Theileriosis and tick fever are infections of cattle by (different) protozoan parasites spread by infected ticks. The parasites can rupture red blood cells (haemolytic anaemia) and produce jaundice.
- Leptospirosis is a bacterial infection, often spread by rats, that can also result in jaundice from haemolytic anaemia. Leptospirosis is a zoonotic disease; you and your workers may be at risk if cattle are infected.
- Anaemic animals often have pale gums, jaundice (yellowing of eyes and mucous membranes), lethargy, may abort, collapse and can die.
- Chronically affected animals have ill thrift, pale gums, jaundice and death (especially after a stressful event).
- Photosensitive animals develop crusty lesions on less well-covered parts of the body, like the ears, face and nose.
- Veterinarians assist in diagnosis and management.
- The first step is to identify the cause of jaundice; is it due to rupture of red blood cells (haemolysis) or liver damage? Is there an infectious component?
- Immediately remove animals from the source of toxicity.
- Provide animals with access to shade if showing signs of photosensitisation.
- Feed oats and cereal hay and prevent access to green pick for 6 weeks to prevent photosensitisation.
- Minimise stress and avoid yarding, especially if anaemic.
- Vaccinate against leptospirosis and consider vaccination against tick fever if in an infected tick region.
- Manage movement of cattle to minimise contact with bush ticks (for Theileria)
- Limit grazing of paddocks with toxic plants—especially naïve cattle on lantana.