Lupine-induced Crooked Calf Disease and a Management method to Reduce Incidence

Abstract

Crooked calf disease is produced when pregnant cows between the 40th and 70th days of gestation graze certain members of the genus Lupinus that contain the quinolizidine alkaloid anagyrine. Calves born to these cows may have twisted or bowed limbs (arthrogryposis), twisted or bowed spine (scoliosis or kyphosis), twisted neck (torticollis), cleft palate, or a combination of any of these. The concentration of the teratogen anagyrine in these lupines is very high early in growth, decreases to a low level during flowering, rises abruptly in mature seeds, and decreases to a very low level after seeds have dropped. Data collected from 6 ranches for 8- to 25-year periods showed no consistent correlation between incidence of the disease and the free-choice feeding of a variety of mineral supplements. Marked variation in incidence did occur, however, during these periods. The variation was related to the period of gestation at which the cows grazed the lupine and to the stage of growth of the lupine-in other words, the amount of anagyrine ingested. Management programs that prevent pregnant cows from eating highly teratogenic early growth or seed-stage lupine plants between gestation days 40 and 70 will reduce crooked calf disease incidence.