Photosensitization of cattle in southeast Texas: identification of phototoxic activity associated with Cooperia pedunculata.
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.
Agricultural Research Service, USDA, College Station, TX 77841.
L D
LD
Rowe
J O
JO
Norman
D E
DE
Corrier
S W
SW
Casteel
B S
BS
Rector
E M
EM
Bailey
J L
JL
Schuster
J C
JC
Reagor
D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000209:etiology*; D004817:Epidermis / Q000473:pathology; D005260:Female; D008297:Male; D051379:Mice; D010787:Photosensitivity Disorders / Q000209:etiology / Q000473:pathology / Q000662:veterinary*; D010939:Plant Poisoning / Q000150:complications / Q000662:veterinary*; D013781:Texas