Spontaneous poisoning by Hovenia dulcis in dairy cattle in Southwest Parana, Brazil

Abstract

Livestock poisoning by plants is a frequent occurrence which determines severe losses, such as the fall in the milk and meat production, the cost of expensive treatments, the state of immunosuppression, or even the animal's death. Cattle ingest toxic plants only when there is food shortage, when they cannot select what they eat, or when they ingest food for preference, which is the case of Hovenia dulcis fruits, very rich in sucrose. This plant is widely distributed in the southern and southeastern Brazilian regions. In literature, there are some cases of severe human liver injury associated with a long-term of H. dulcis leaf and fruit tea intake, and only one report regarding spontaneous poisoning of goats caused by this plant ingestion. However, its toxic effects associated with spontaneous ingestion by cattle have never been reported. This paper reports the first case of spontaneous poisoning in cattle by H. dulcis, which occurred in a dairy farm in southwest Paraná, Brazil. Three cattle individuals showed anorexia, ruminal atony, severe diarrhea and neurological tournament, head pressing, blindness, ataxia, and circling. The necropsy of the animals was done, and the remaining alterations were restricted to the digestive system and brain. The clinical signs presented by the animals are characteristic of polioencephalomalacia (PEM), caused by changes in the thiamine metabolism. Furthermore, clinical signs, gross, and microscopic lesions as well as the large amount of the plant throughout the digestive segment led to a diagnosis.

Plants causing poisoning outbreaks of livestock in South America: A review

“… Plants Species affected Region Main references Aeschynomene indica Pigs Southern Brazil Riet-Correa et al (2003) ; Oliveira et al (2004) Bambusa vulgaris Horses Northern Brazil Barbosa et al (2006a) Casearia commersoniana Goats Northeastern Brazil Bezerra et al (2012) Centaurea solstitialis Horses Argentina and Uruguay Perdomo and Freitas (1978) ; Giannitti and Margineda (2014) Condalia microphylla Cattle and pigs La Pampa province, Argentina Bedotti et al (2006) ; Delgado et al (2011) Equisetum spp. Horses Southeastern Brazil Alvim (1948) Erythroxylum argentinum Sheep Southern Brazil Barros et al (2004) Erythroxylum deciduum Sheep Southern Brazil Borelli et al (2011) Halimium brasiliense Sheep Southern Brazil and Uruguay Riet-Correa et al (2009) Hovenia dulcis Goats and cattle Southern Brazil Colodel et al (1998) ; Bernardi et al (2016) Hybanthus calceolaria Cattle, sheep, and goats Northeastern Brazil Carvalho et al (2014) Hypochaeris radicata Horses Southern Brazil and Southern Chile Araya et al (1998) ; Araújo et al (2008) ; Rodrigues et al (2008) ...…”

Hovenia dulcis Thumberg: Phytochemistry, Pharmacology, Toxicology and Regulatory Framework for Its Use in the European Union

“…Also, some cases of spontaneous poisoning in cattle and goats caused by H. dulcis fruits have been described. Animals developed an acute toxicity that led to their death [97,98]. Therefore, it is very crucial to carry out further research on safety profile of H. dulcis extracts in order to improve the correct use and discourage its misuse.…”