Lupinosis
| Lupinosis | |
|---|---|
| Other names | Phomopsin toxicosis |
| Specialty | Veterinary medicine, Toxicology |
| Symptoms | Liver damage, jaundice, lethargy, inappetence, death |
| Complications | Abortion, reduced lambing, poor wool quality, nutritional myopathy |
| Usual onset | Acute, subacute, or chronic |
| Duration | Variable depending on exposure |
| Causes | Ingestion of phomopsins produced by Diaporthe toxica |
| Risk factors | Grazing on dead lupin plants (especially in summer/autumn) |
| Diagnostic method | Histopathology, clinical signs, grazing history |
| Prevention | Avoid grazing lupin stubble or infected plants |
| Treatment | Supportive care, removal from toxic feed |
| Prognosis | Poor if severe liver damage is present |
| Frequency | Endemic in parts of Western Australia |
| Deaths | Significant economic losses in livestock |
Lupinosis, also known as phomopsin toxicosis or mycotoxinic lupinosis, is a mycotoxicosis primarily affecting sheep, caused by ingestion of phomopsins—mycotoxins produced by the fungus Diaporthe toxica (formerly identified as Phomopsis leptostromiformis). The fungus colonizes lupin plants following seed emergence but lies dormant until saprophytic growth occurs when plants senesce at the end of the season. The disease has also been reported in cattle, goats, donkeys, horses, and pigs, and has been experimentally induced in various other species, including rabbits, guinea pigs, mice, rats, dogs, ducklings, and chickens.
First recognized in Germany in 1872 following numerous sheep deaths linked to lupin ingestion, lupinosis has since been reported in countries such as the United States, Poland, New Zealand, Australia, South Africa, and Spain. In Australia, particularly Western Australia, where lupin stubble is extensively used as fodder, the disease has had a significant economic impact. In 1983, lupinosis was estimated to cause an annual economic loss of $16.3 million (1983 AUD).
Clinically, lupinosis is characterized by severe liver damage, leading to symptoms such as inappetence, weight loss, lethargy, jaundice, and often death. Microscopically, the disease is marked by arrested and abnormal mitosis of hepatocytes. The disease course may be acute, subacute, or chronic, depending on the amount and duration of phomopsin exposure. Additional effects include reproductive issues like abortions in late pregnancy, embryonic deaths, reduced lambing percentages, decreased wool production and quality, nutritional myopathy, and starvation ketosis in cattle.