Intoxicação experimental pelos frutos de uva-Japão, hovenia dulcis (rhamnaceae), em bovinos / Experimental poisoning by the fruits of hovenia dulcis (rhamnaceae) in cattle

Hovenia dulcis Thunberg (uva-Japão) é uma árvore caducifolia nativa da China e de alguns lugares do Japão. Nos últimos anos essa planta foi utilizada como forma de sombreamento para aviários no Oeste e Meio-Oeste de Santa Catarina e passou a disseminar-se por toda a região. Os bovinos comem avidamente seus frutos maduros quando caem ao chão. Suspeitas de intoxicação ocorreram no outono e início de inverno e coincidiam com a maturação dos frutos. A doença foi reproduzida em 2004 por outros autores através da administração dos frutos a bovinos, em dose única de 24,5g/kg. Nos anos subsequentes não ocorreram reclamações sobre a intoxicação pelos frutos dessa planta, embora, muitos criadores afirmavam que os bovinos, na temporada de maturação, continuavam a ingerir os frutos. Experimentalmente, nove bovinos que receberam frutos da planta em doses únicas entre 30 e 50g/kg, apenas dois bovinos adoeceram gravemente e um morreu. O quadro clínico e as lesões foram semelhantes à intoxicação reproduzida em 2004, porém, a dose necessária para reproduzirmos a doença foi 100% superior à dose tóxica preconizada como letal em 2004.

Hovenia dulcis Thunberg (Japan grape) is a deciduous tree native of China and some parts of Japan. Over the last years, the tree has been used for shading in poultry farms of western and middle western Santa Catarina, spreading in the region. Cattle ingest the ripe fruits of H. dulcis fallen to the ground. The fruits were suspected to cause poisoning during fall and early winter, period of their maturation. The disease has been reproduced in 2004 by other authors with a single dose of 24.5g/kg. In the subsequent years no complaints regarding the toxicity of H. dulcis fruits have been reported, although many breeders observed that cattle continued to consume them during the ripening season. We administered the fruits at single doses of 30-50g/kg to nine calves, only two of them became seriously ill and one died. The clinical picture and lesions were similar to the poisoning reproduced in 2004, however, the dose required to reproduce the poisoning was 100% higher than the lethal dose found in 2004.

Outbreak of ataxia in pigs associated with consumption of piquillín (Condalia microphylla).

The plant piquillín (Condalia microphylla) grows in arid regions of Argentina and is the cause of mal del piquillín in cattle. The salient histologic features of this leukomyelopathy are vacuolation of white matter and axonal degeneration in the spinal cord. The histologic lesions can be experimentally reproduced in cattle and pigs by feeding milled bark of the plant, but naturally occurring piquillín toxicosis has not been reported previously in pigs. The authors report an outbreak of progressive ataxia on an Argentine hog farm, where partially consumed piquillín plants were found in the pens of affected pigs. Histologic lesions included vacuolation of white matter, edema, and mild axonal degeneration in lumbosacral segments of the cord. The diagnosis of mal del piquillín was based on the history, clinical signs, histologic changes, and elimination of other potential causes of leukomyelopathy. No new outbreaks developed after elimination of piquillín from the hog lots. Results of this investigation indicate that C microphylla toxicosis can affect pigs under natural conditions and should be included in the differential diagnosis for porcine ataxia and leukomyelopathy in regions where the plant grows.