Spontaneous photosensitization by Heterophyllaea pustulata Hook. f. (Rubiaceae), in sheep from Northwestern Argentina

MICHELOUD, J. F.; COLQUE-CARO, L. A.; COMINI, L. R.; CABRERA, J. L.; NÚÑEZ-MONTOYA, S.; MARTINEZ, O. G.; GIMENO, E. J.

TROPICAL ANIMAL HEALTH AND PRODUCTION

SPRINGER

Lugar: Berlin; Año: 2017 vol. 49

0049-4747

Heterophyllaea pustulata Hook. f. (Rubiaceae) is aphototoxic plant. It grows in the Andean area of northwest ofArgentina, and it causes significant economic losses in thelivestock. This plant induces dermal lesions by photosensitizationprobably due to its content of photosensitizing anthraquinones.This paper describes an outbreak of poisoning inCorriedale sheepfold, which had an incidence of 49%. Earskin biopsies and blood samples were collected of six affectedanimals. Liver enzymes remained within the reference limits.Histopathologically, a deep necrotizing dermatitis was identifiedin all samples. H. pustulata was identified in the areas ofgrazing. Anthraquinone concentration in leaves was 0.84%p/p, expressed as rubiadin. All findings allow us to concludethat the diagnosis is a primary photosensitization. Huge regionaleconomic losses could be attributed to H. pustulatapoisoning, although its toxicity has been little studied.