Intoxicação por Senecio brasiliensis em bezerros: padrão e evolução de lesões hepáticas

Abstract

ABSTRACT.-Panziera W., Gonçalves M.A., Oliveira L.G.S., Lorenzett M.P., Reis M., Hammerschmitt M.E., Pavarini S. Characterization and evolution of liver lesions during the outbreak are also described. Two hundred and six 4-month-old female calves were weaned and placed in a 25-hectare pasture heavily infested by S. brasiliensis at of varying growth stages. The calves remained in this pasture for three months and were later transferred to another area where six calves aged 7-8-month-old developed clinical signs including unthriftiness, diarrhea, and subcutaneous dependent edema in the submandibular region. All these six affected calves died within 15 days from the onset of clinical signs and one of those was necropsied. Grossly the first of three patterns of hepatic lesions described in this report was observed and it was characterized by an enlarged liver, with round borders and an orange hue to the capsular and cut surfaces. Histologically there was marked diffuse vacuolar hepatocellular degeneration, bilestasis, hepatocellular megalocytosis, and mild bile duct proliferation and periportal fibrosis. Two months after the onset of the outbreak, in another visit to the farm, it was observed that an additional 28 calves got sick and 14 died. Affected calves observed in this second on-site visit were 9-10 month-old and their main clinical sign was photosensitization characterized by varying degrees of photophobia, tearing from the eyes, marked drooling, mucopurulent ocular discharge, increased nasal secretion, and ventral diphtheric glossitis. Two of the fourteen calves that died were necropsied and displayed the second pattern of hepatic lesions observed in the outbreak. Liver had smooth and whitish capsular surfaces and a moderate decrease in size. There was moderate irregularity to the cut surface of hepatic parenchyma and pale areas intercalated with red ones. Histologically there was marked periportal fibrosis, marked bile duct proliferation, hepatocellular megalocytosis, focal areas of hepatocellular necrosis, and hemorrhage and veno-occlusive changes. In this second on-site visit, GGT serum activity was determined in 15 affected calves and 13 of them had increased values (26-175 U/L). Seven months after the onset of the outbreak, a third visit was made to the farm when was learned that and additional 27 calves have been affected, 23 of which died within a period of 40 days. At the necropsy of three of these calves the third pattern of hepatic lesions were observed. The liver was decreased in size and markedly firm. The capsular surface was smooth and whitish and the capsular surface 1 Recebido em 1 de junho de 2016.Aceito para publicação em 29 de agosto de 2016.

Poisoning of cattle by Senecio spp. in Brazil: a review

“…Several studies have demonstrated the sensitivity of cattle to Senecio intoxication and the high frequency of cases in cattle (Méndez et al 1987, Driemeier et al 1991, Basile et al 2005, Pedroso et al 2007, Grecco et al 2010, Giaretta et al 2014a, Panziera et al 2017. Typically, spontaneous disease is observed in 2-year-old or older grazing cattle (Barros et al 2007, Barros 2016.…”

“…Typically, spontaneous disease is observed in 2-year-old or older grazing cattle (Barros et al 2007, Barros 2016. Occurrence in calves is uncommon (Basile et al 2005, Panziera et al 2017). However, it has been shown experimentally that young cattle are more susceptible to intoxication than are older cattle (Torres & Coelho 2008).…”

“…2D), ears, udder and teats, periocular and vulvar skin, the skin of the dorsum, and ventral aspects of the tongue. Initially, the signs are characterized by photophobia, lacrimation, nasal secretion, and erythematous and exudative cutaneous lesions that evolve to severe crust lesions (Motta et al 2000, Tokarnia et al 2012, Giaretta et al 2014a, Panziera et al 2017). The lesion on the tongue is observed in the ventral portion (ventral diphtheric glossitis).…”

Shapes of pathology

“…In Brazil, several plants are associated with hepatogenous photosensitization including Brachiaria spp., Lantana spp., Panicum dichotomiflorum, Myoporum laetum, Enterolobium gummiferum, Enterolobium contortisiliquum and Senecio spp. (Tokarnia et al 2012a, Leal et al 2017, Panziera et al 2017. The mycotoxin sporidesmin, produced by the fungus Pithomyces chartarum, and toxic plants including Lantana camara (Morton 1994), Panicum coloratum (kleingrass), among other Panicum species are reported as causes for hepatogenous photosensitization in the United States (Chen et al 2019).…”

In vitro ovicidal effect of a Senecio brasiliensis extract and its fractions on Haemonchus contortus

“…Senecio brasiliensis is a native species found in south and southeast of Brazil [15]. It is toxic to the livestock [16, 17] due to the presence of pyrrolizidine alkaloids (PAs), which are widely found in the Asteraceae, Boraginaceae, and Fabaceae families [18, 19]. However, the leaves and inflorescence of S. brasiliensis are used in traditional medicine for the treatment of stomach pain [20], a practice justified by the antiulcerogenic and cytoprotective effect of PAs [21, 22].…”