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

• Published in: Tropical animal health and production Vol. 49; no. 7; pp. 1553 - 1556
• Main Authors: Micheloud, J. F., Colque-Caro, L. A., Comini, L. R., Cabrera, J. L., Núñez-Montoya, S., Martinez, O. G., Gimeno, E. J.
• Format: Journal Article
• Language: English
• Published: Dordrecht Springer Netherlands 01.10.2017; Springer Nature B.V
• Subjects: Animals; Anthraquinone; Anthraquinones; Argentina - epidemiology; Biomedical and Life Sciences; Dermatitis; Dermatitis - epidemiology; Dermatitis - etiology; Dermatitis - veterinary; Disease Outbreaks - veterinary; Ear; Economic impact; Economics; Incidence; Lesions; Life Sciences; Liver; Livestock; Outbreaks; Photosensitivity Disorders - epidemiology; Photosensitivity Disorders - etiology; Photosensitivity Disorders - veterinary; Photosensitization; Poisoning; Regional development; Rubiaceae - poisoning; Sheep; Sheep Diseases - epidemiology; Sheep Diseases - etiology; Short Communications; Skin; Toxicity; Veterinary Medicine/Veterinary Science; Zoology; Primary photosensitization; Poisoning plants; Phototoxic; Dermatitis
• ISSN: 0049-4747; 1573-7438
• DOI: 10.1007/s11250-017-1354-0

Heterophyllaea pustulata Hook. f. (Rubiaceae) is a phototoxic plant. It grows in the Andean area of northwest of Argentina, and it causes significant economic losses in the livestock. This plant induces dermal lesions by photosensitization probably due to its content of photosensitizing anthraquinones. This paper describes an outbreak of poisoning in Corriedale sheepfold, which had an incidence of 49%. Ear skin biopsies and blood samples were collected of six affected animals. Liver enzymes remained within the reference limits. Histopathologically, a deep necrotizing dermatitis was identified in all samples. H. pustulata was identified in the areas of grazing. Anthraquinone concentration in leaves was 0.84% p/p, expressed as rubiadin. All findings allow us to conclude that the diagnosis is a primary photosensitization. Huge regional economic losses could be attributed to H. pustulata poisoning, although its toxicity has been little studied.