Photosensitization of cattle in southeast Texas: identification of phototoxic activity associated with Cooperia pedunculata
Rowe, L.D.; Norman, J.O.; Corrier, D.E.; Casteel, S.W.; Rector, B.S.; Bailey, E.M.; Schuster, J.L.; Reagor, J.C.
American Journal of Veterinary Research 48(11): 1658-1661
1987
ISSN/ISBN: 0002-9645 PMID: 3434912 Document Number: 299393
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 C. pedunculata, a native, perennial forb of the 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. It is concluded that C. pedunculata is involved in recurring PS.