General poisoning notes:

Astragalus lentiginosus is a native plant found in south-central British Columbia. Ingesting the plant causes a variety of problems. Plants contain the alkaloid swainsonine, which can cause locoism. The common symptoms are impairment of the nervous system, depression, and excitement when disturbed. Teratogenic effects have also been noted in lambs and foals. At high altitudes (above 2120 m), cattle suffer from congestive heart failure (swainsonine influences the vascular system). This plant is a major poisonous range plant in the western United States. It is not abundant anywhere in Canada (Cheeke and Schull 1985, Panter et al. 1988).

References:

Cheeke, P. R., Shull, L. R. 1985. Natural toxicants in feeds and poisonous plants. AVI Publishing Company, Inc., Westport, Conn., USA. 492 pp.

James, L. F., Van Kampen, K. R. 1971. Effects of locoweed intoxication on the genital tract of the ram. Am. J. Vet. Res., 32: 1253-1256.

LeGrande, C. E., James, L. F., McMullen, R. W., Panter, K. E. 1985. Reduced progesterone and altered cotyledonary prostaglandin values induced by locoweed (Astragalus lentiginosus) in sheep. Am. J. Vet. Res., 46: 1903-1907.

Panter, K. E., Bunch, T. D., James, L. F., Sisson, D. V. 1987. Ultrasonographic imaging to monitor fetal and placental developments in ewes fed locoweed (Astragalus lentiginosus). Am. J. Vet. Res., 48: 686-690.

Panter, K. E., James, L. F., Hartley, W. J. 1989. Transient testicular degeneration in rams fed locoweed (Astragalus lentiginosus). Vet. Hum. Toxicol., 31: 42-46.

Panter, K. E., James, L. F., Nielson, D., Molyneux, R. J., Ralphs, M. H. 1988. The relationship of Oxytropis sericea (green and dry) and Astragalus lentiginosus with high mountain disease in cattle. Vet. Hum. Toxicol., 30: 318-323.

Ralphs, M. H., Panter, K. E., James, L. F. 1990. Feed preferences and habituation of sheep poisoned by locoweed. J. Anim. Sci., 68: 1354-1362.

Tulsiani, D. R., Broquist, H. P., James, L. F., Touster, O. 1984. The similar effects of swainsonine and locoweed on tissue glycosidases and oligosaccharides of the pig indicate that the alkaloid is the principal toxin for induction of locoism. Arch. Biochem. Biophys., 232: 76-85.

Van Kampen, K. R., James, L. F. 1972. Sequential development of the lesions in locoweed poisoning. Clin. Toxicol., 5: 575-580.

Nomenclature:

Scientific Name: Astragalus lentiginosus Dougl.

Vernacular name(s): Astragalus (A. lentiginosus)

Scientific family name: Leguminosae

Vernacular family name: pea

References:

Agriculture Quebec. 1975. Noms des maladies des plantes du Canada/ Names of plant diseases in Canada. , Quebec City, Que., Canada. 288 pp.

Alex, J. F., Cayouette, R., Mulligan, G. A. 1980. Common and botanical names of weeds in Canada/Noms populaire et scientifiques des plantes nuisibles du Canada. Revised. Agric. Can. Publ., Ottawa, Ont., Canada. 132 pp.

Bailey, L. H., Bailey, E. Z. 1976. Hortus third. Revised. MacMillan, New York, N.Y., USA. 1290 pp.

Scoggan, H. J. 1978, 1979. The flora of Canada. Nat. Mus. Nat. Sci. (Ottawa) Publ. Bot. 7(1)-7(4). 1711 pp.

Van Wijk, H. L. 1911. A dictionary of plant names. Martinus Nijhoff, The Hague, The Netherlands. 1444 pp.

Victorin, M. 1964. Flore Laurentienne. 2nd ed. Univ. Montreal, Montreal, Que., Canada. 952 pp.

Geographic Information

British Columbia

References:

Bailey, L. H., Bailey, E. Z. 1976. Hortus third. Revised. MacMillan, New York, N.Y., USA. 1290 pp.

Boivin, B. 1966, 1967. Énumération des plantes du Canada. Provencheria 6. Nat. Can. (Que.) 93: 253-274; 371-437; 583-646; 989-1063. 94: 131-157; 471-528; 625-655.

Toxic parts:

flowers
leaves
seeds
stems

References:

James, L. F., Van Kampen, K. R. 1971. Effects of locoweed intoxication on the genital tract of the ram. Am. J. Vet. Res., 32: 1253-1256.

LeGrande, C. E., James, L. F., McMullen, R. W., Panter, K. E. 1985. Reduced progesterone and altered cotyledonary prostaglandin values induced by locoweed (Astragalus lentiginosus) in sheep. Am. J. Vet. Res., 46: 1903-1907.

Panter, K. E., James, L. F., Hartley, W. J. 1989. Transient testicular degeneration in rams fed locoweed (Astragalus lentiginosus). Vet. Hum. Toxicol., 31: 42-46.

Panter, K. E., James, L. F., Nielson, D., Molyneux, R. J., Ralphs, M. H. 1988. The relationship of Oxytropis sericea (green and dry) and Astragalus lentiginosus with high mountain disease in cattle. Vet. Hum. Toxicol., 30: 318-323.

Tulsiani, D. R., Broquist, H. P., James, L. F., Touster, O. 1984. The similar effects of swainsonine and locoweed on tissue glycosidases and oligosaccharides of the pig indicate that the alkaloid is the principal toxin for induction of locoism. Arch. Biochem. Biophys., 232: 76-85.

Van Kampen, K. R., James, L. F. 1972. Sequential development of the lesions in locoweed poisoning. Clin. Toxicol., 5: 575-580.

Notes on Toxic plant chemicals:

Swainsonine, the chemical involved in locoism, is found in several plants occurring in Canada, including Astragalus bisulcatus, A. lentiginosus, Oxytropis lambertii, and O. sericea. This indolizidine alkaloid causes locoism in cattle, horses, and sheep; it also causes teratogenic deformities in lambs, calves, and foals. In addition, at high altitudes (above 2120 m) it contributes to congenital heart failure in calves and cows (Cheeke and Schull 1985).

References:

Cheeke, P. R., Shull, L. R. 1985. Natural toxicants in feeds and poisonous plants. AVI Publishing Company, Inc., Westport, Conn., USA. 492 pp.

Molyneux, R. J., James, L. F. 1982. Loco intoxication: indolizidine alkaloids of spotted locoweed (Astragalus lentiginosus). Science (Wash. D. C.), 216: 190-191.

Tulsiani, D. R., Broquist, H. P., James, L. F., Touster, O. 1984. The similar effects of swainsonine and locoweed on tissue glycosidases and oligosaccharides of the pig indicate that the alkaloid is the principal toxin for induction of locoism. Arch. Biochem. Biophys., 232: 76-85.

Animals/Human Poisoning:

Note: When an animal is listed without additional information, the literature (as of 1993) contained no detailed explanation.

Cattle

General symptoms of poisoning:

abdominal edema
appetite, loss of
duodenum, edema of
gall bladder, enlarged
jaw(lower), edema of
thorax(ventral),edema
throat, edema of
ventrical(right),edema

References:

Panter, K. E., James, L. F., Nielson, D., Molyneux, R. J., Ralphs, M. H. 1988. The relationship of Oxytropis sericea (green and dry) and Astragalus lentiginosus with high mountain disease in cattle. Vet. Hum. Toxicol., 30: 318-323.

Horses

Sheep

General symptoms of poisoning:

abortion
blisters, weeping
brain, vacuolation of
cytoplasm vacuolation
death
depression
eyes, dull
fetus, dead
gait, unsteady
heart rate, elevated
incoordination
kidney, congestion of
kidney, vacuolation of
lethargy
liver, congestion of
muscle, weakness of
sperm, detached tails
sperm mobility, poor
testicle degeneration
ventrical(right),edema
ventricle(right),round
weakness

Notes on poisoning:

Astragalus lentiginosus caused fetal abortion in sheep and clinical signs of locoism in pregnant ewes. It also caused fluid accumulation in the placenta, altered cotyledonary development, and decreased fetal heart rates causing cardiac irregularity. At necropsy the fetuses had hypertrophy of the heart, right ventricular dilation, rounded apex of the heart, and generalized edema (Panter et al. 1987).

References:

James, L. F., Van Kampen, K. R. 1971. Effects of locoweed intoxication on the genital tract of the ram. Am. J. Vet. Res., 32: 1253-1256.

LeGrande, C. E., James, L. F., McMullen, R. W., Panter, K. E. 1985. Reduced progesterone and altered cotyledonary prostaglandin values induced by locoweed (Astragalus lentiginosus) in sheep. Am. J. Vet. Res., 46: 1903-1907.

Panter, K. E., Bunch, T. D., James, L. F., Sisson, D. V. 1987. Ultrasonographic imaging to monitor fetal and placental developments in ewes fed locoweed (Astragalus lentiginosus). Am. J. Vet. Res., 48: 686-690.

Panter, K. E., James, L. F., Hartley, W. J. 1989. Transient testicular degeneration in rams fed locoweed (Astragalus lentiginosus). Vet. Hum. Toxicol., 31: 42-46.

Ralphs, M. H., Panter, K. E., James, L. F. 1990. Feed preferences and habituation of sheep poisoned by locoweed. J. Anim. Sci., 68: 1354-1362.

Van Kampen, K. R., James, L. F. 1972. Sequential development of the lesions in locoweed poisoning. Clin. Toxicol., 5: 575-580.

Swine

General symptoms of poisoning:

brain, vacuolation of
coat, rough and dry
cytoplasm vacuolation
depression
eyes, dull
incoordination
kidney, vacuolation of

References:

Tulsiani, D. R., Broquist, H. P., James, L. F., Touster, O. 1984. The similar effects of swainsonine and locoweed on tissue glycosidases and oligosaccharides of the pig indicate that the alkaloid is the principal toxin for induction of locoism. Arch. Biochem. Biophys., 232: 76-85.

Information Source: ©Canadian Poisonous Plants Information System, Canadian Biodiversity Information Facility.