Photosensitization of cattle in southeast Texas: identification of phototoxic activity associated with Cooperia pedunculata. Academic Article uri icon


  • A microbiological assay (Candida albicans) was used to screen plants in southeast Texas where bovine photosensitization (PS) of unknown cause was a recurring problem. Phototoxic activity was identified associated with dead leaf tips of Cooperia pedunculata, a native, perennial forb of the Amaryllis family (Amaryllidaceae) from central, southeast, and south Texas and parts of Mexico. A syndrome compatible with naturally occurring PS in cattle was induced in laboratory mice after oral administration of dead leaf material from C pedunculata. Availability and phototoxic activity of dead leaf material of C pedunculata corresponded with occurrence of PS in cattle. Seemingly, C pedunculata was involved in recurring PS.

published proceedings

  • Am J Vet Res

author list (cited authors)

  • Rowe, L. D., Norman, J. O., Corrier, D. E., Casteel, S. W., Rector, B. S., Bailey, E. M., Schuster, J. L., & Reagor, J. C

citation count

  • 12

complete list of authors

  • Rowe, LD||Norman, JO||Corrier, DE||Casteel, SW||Rector, BS||Bailey, EM||Schuster, JL||Reagor, JC

publication date

  • November 1987