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Distinguishing features
Lupines are perennial or sometimes annual herbs with
palmately compound leaves; their leaflets are narrow; their
flowers are in terminal racemes, pea-like, often blue, but yellow or white in some
species. They have pods up to 1 inch in length. |
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Description.
Lupines are in the Legume family which is characterized by irregular, five-petaled
flowers with a central "keel." Flowers are most often blue; occasionally white,
red or yellow varieties are seen. Leaves: the leaf, a palmately compound leaf
with five to seven elongated, ovoid leaflets, is somewhat distinctive. |
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Geographic range.
Both cultivated garden lupines and native lupines of the
western rangelands are toxic. In rangelands, they occur from the dry, open
ranges of the Great Plains to the Rocky Mountains. |
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Toxic principle.
Lupinine, a quinolizidine alkaloid, induces nicotinic
effects in animals. Leaves, seeds and fruits all contain lupinine, which
is retained in dried plants. Pods may concentrate the toxin, becoming a source
of poisoning during the winter season when livestock are moved through infested
areas or contaminated hay is fed. |
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Toxicity. Lupines are a major toxic problem in range sheep. Lupines
are toxic when ingested at 1% or less of body weight. |
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Clinical
signs
Salivation,
ataxia, seizures and dyspnea are major acute clinical signs and are
more common in sheep that in cattle.
Head-pressing
and excitement may also be seen.
Effects
not related to the nervous system include the "crooked calf
syndrome" (i.e., carpal flexure, torticollis and scoliosis in
calves exposed in utero during days 40-70 of gestation). The
toxic principle for this effect is the alkaloid anagyrine.
Interestingly, anagyrine is not teratogenic to sheep fetuses.
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It
has been proposed that cattle are affected by anagyrine due to ruminal
metabolism of the alkaloid to a teratogenic metabolite. The
mode of teratogenic action may involve an immobilizing affect on the
fetus; skeletal malformations occur because the fetus remains in one
position for extended periods of time. |
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Laboratory
diganosis: not
useful
Lesions:
characteristic
limb and spinal deformities
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Treatment.
Oral detoxification and control of seizures in severely
affected animals is the only recourse. |
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Prevention
through correct range management is preferred. Alter
grazing rotations so that cows are not exposed to lupines between days 40 to 70
of gestation. |
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