Synonyms

No known synonym

Name of the disease in English

Poisoning by a photosensitizing plant

The disease in brief

Photosensitization which makes the skin very sensitive to light can come from plant poisoning:

-Des plantes contenant la substance photosensibilisante provoque une photosensibilisation primaire : La renouée persicaire (Plygonum persicaria), le sarrasin 5fagopyrum sp.), le millepertius (Hypericum sp.), lforage legumes: White clover (Trifolium repens), hybrid clover (Trifolium hybridum), alfalfa (Medicago sativa), vetch (Vicia sp.)

-Des plantes hépatotoxiques  comme le lupin (Lupinus sp.), le sorgho (Sorghum sp.) et la sporidesmine une mycotoxine se développement sur de l’herbe desséchée quand la pluie revient: Ils provoquent une photosensibilisation secondaire.

-La phylloérythrine,photosensibilisante, est un dérivée de la chlorophylle qui se forme dans le tube digestif des ruminant et évacuée en partie dans les fecés, en partie par le foie via la bile si tout va bien; si la fonction hépatique est perturbée ou l’évacuation de la bile empêchée, la phyloérythrine se retrouve dans le sang et dans la peau.Elle provoque une photosensibilisation secondaire.

Clinic & diagnosis

Photosensitization is suspected when specific lesions are seen in specific locations or with particular behavior:

-Le poil est hérissé, ou la peau est rouge et douloureuse au toucher, puis la eau perd ses poils, prend un brulé ou cartonné (parfois se détache en lambeaux), enfin devient crouteuse, épaissie et grisâtre.

-These lesions are limited to white or light skin, or hairless areas, or the udder or teats or muzzle or lips; or the bovine may fear light, be restless or exhibit colic-like symptoms by tapping its belly.

Typical sign of the disease

No description

Pictures

See below

Diagnostic formulas

No description

Differential diagnosis

-Leptospirosis UR15

– Intoxication/Senecio-N27 

– Congenital calf porphyria OR “pink tooth disease” – DR42 

Confirm a suspicion?

The toxic plant can be found by a field survey. It is also possible to confirm secondary photosensitization by taking blood on EDTA to measure gamma GT, which is a marker of cholestasis.

Prognosis and treatment

Put the cattle in the shade and protect them from the toxin, but also put in place:

-Anti-inflammatory treatment is useful in non-pregnant patients:

-Local treatment of skin lesions

The prognosis is reserved in all cases; photosensitization secondary to liver damage may remain of no economic value after recovery.

Prevention

Identify risky plants in cattle feed or their environment; remove them from the ration or reduce their quantity; deprive cattle of access to risky wild plants.

References

Jouve C. (2009) Contribution to the development of a website on plant toxicology in ruminants: Monographs of the main plants incriminated according to data from CNITV-Th. Med .Vet. Claude Bernard-Lyon University1 271p