Lupines (Lupinus spp) cause two distinct
forms of poisoning in livestock—lupine poisoning
and lupinosis. The
former is a nervous syndrome caused by alkaloids present in bitter lupines; the
latter is a mycotoxic disease characterized by liver injury and jaundice, which
results mainly from the feeding of sweet lupines. Lupinosis is important in
Australia and South Africa and also has been reported from New Zealand and Europe.
There is increasing use of sweet lupines, either as forage crops or through feeding
of their residues after grain harvest, as strategic feed for sheep in Mediterranean
climate zones. Sheep, and occasionally cattle and horses, are affected, and pigs are
Etiology and Pathogenesis
The causal fungus is Phomopsis
leptostromiformis, which causes Phomopsis
stem-blight, especially in white and yellow lupines; blue varieties are
resistant. It produces sunken, linear stem lesions that contain black, stromatic
masses, and it also affects the pods and seeds. The fungus is also a saprophyte
and grows well on dead lupine material (eg, haulm, pods, stubble) under
favorable conditions. It produces phomopsins as secondary metabolites on
infected lupine material, especially after rain.
Clinical Findings, Lesions, and Diagnosis
Clinical changes are mainly attributable to toxic
hepatocyte injury, which causes mitotic arrest in metaphase, isolated cell
necrosis, and hepatic enzyme leakage, with loss of metabolic and excretory
Early signs in sheep and cattle are inappetence and
listlessness. Complete anorexia and jaundice follow, and ketosis is common.
Cattle may show lacrimation and salivation. Ketosis is a common sequela in
pregnant cattle or recently calved cows. Survivors may develop hepatic
cirrhosis. Sheep may become photosensitive, and a skeletal muscle myopathy can
develop. As disease progresses, liver failure may cause hepatoencephalopathy
characterized by stumbling, disorientation, and recumbency before death. In
acute outbreaks, deaths occur in 2–14 days.
In acute disease, icterus is marked. Livers are enlarged,
orange-yellow, and fatty. More chronic cases show bronze- or tan-colored livers
that are firm, contracted in size, and fibrotic. Copious amounts of transudates
may be found in the abdominal and thoracic cavities and in the pericardial sac.
Some animals may have spongiform lesions in the brain.
Feeding of moldy lupine material, together with clinical
signs and increased levels of serum liver enzymes, strongly indicate
Frequent surveillance of sheep and of lupine fodder
material for characteristic black spot fungal infestation, especially after
rains, is advised. The utilization of lupine cultivars, bred and developed for
resistance to P leptostromiformis is advocated. Oral doses of
zinc (≥0.5 g/day) have protected sheep against liver injury induced by
Last full review/revision December 2014 by Gary D. Osweiler, DVM, MS, PhD