Baccharis Pteronioides Toxicity in Livestock and Hamsters

Abstract

Abstract. Baccharis pteronioides DC has been intermittently associated with livestock poisoning in the southwestern United States. In 2004, nearly 100 cows were reported poisoned by B. pteronioides in southern New Mexico. Initial field studies and postmortem examinations found drought conditions, evidence of B. pteronioides consumption, and a reported mortality of nearly 40%. Because postmortem materials were unsuitable for further examination, plant samples were collected for feeding trials and chemical evaluation. Forty-eight Syrian hamsters (8 weeks old) were randomly divided into 4 groups and dosed with 0, 50, 100, and 200 mg of B. pteronioides for 10 days. After dosing, the hamsters were necropsied; sera were analyzed biochemically; and tissues were collected and evaluated histologically. The hamsters treated with 200 mg and several of the 100-mg animals developed anorexia and diarrhea. These animals developed multiple hemorrhagic infarcts in the liver and kidney, with severe hemorrhagic enteritis. Histologically, the higherdosed animals had severe necrotizing vasculitis with vascular thrombosis of hepatic and renal vessels. Many glomerular capillaries contained fibrin thrombi. The superficial intestinal and colonic mucosa was necrotic, with extensive hemorrhage and proliferation of luminal bacteria. Lower-dosed animals had mild hepatocellular swelling, with proliferation of intestinal and gastric bacteria and yeast. The findings indicate that at high doses, B. pteronioides is toxic to hamsters and produces lesions that are very similar to bacterial endotoxin-produced vasculitis and infarction. Research to purify and identify the toxin, the toxic dose, and mechanism of toxicity are ongoing.

Trophic preferences in an assemblage of mammal herbivores from Andean Puna (Northern Chile)

“…It is worth noting that the shrub species predominantly consumed by ashy chinchilla rat, B. tola, has already been reported in the diet of this species in northern Chile (Cortés et al, 2002b). Baccharis tola belongs to a genus composed of species toxic for some herbivores (Alda et al, 2009;Stegelmeier et al, 2009). Terpenes have been isolated from this species (San Martin et al, 1983), being the main secondary compounds of its resin (Langenham, 2003).…”

Experimental poisoning by Baccharis megapotamica var. weirii in buffalo

“…in livestock was never completely resolved (Barros 1998, Rissi et al 2005. It was suggested that dehydration, electrolyte imbalance and septicemia stemming from bacterial invasion through breakdowns in necrotic ruminal epithelium (Rissi et al 2005) and disseminated vascular coagulation (Stegelmeier et al 2009) could play a part. Data from the current experiment suggest that several of these mechanisms of disease production could act concomitantly or in sequence in the pathogenesis and cause of death of buffalo experimentally poisoned by B. megapotamica var.…”

“…This species is suspected of poisoning cattle in both countries (Everist 1981) and proved toxic when administered experimentally to chicks (Duncan et al 1957). B. glomerulifolia, another North American species, was experimentally toxic to mice and chicks (Duncan et al 1957), and B. pteronioides has been associated with cattle poisoning in the southwestern United States (Marsh et al 1920, Stegelmeier et al 2009). B. pteronioides toxicosis was produced in hamsters dosed with 100-200mg of the plant (Stegelmeier et al 2009).…”

“…B. glomerulifolia, another North American species, was experimentally toxic to mice and chicks (Duncan et al 1957), and B. pteronioides has been associated with cattle poisoning in the southwestern United States (Marsh et al 1920, Stegelmeier et al 2009). B. pteronioides toxicosis was produced in hamsters dosed with 100-200mg of the plant (Stegelmeier et al 2009). B. artemisioides causes disease in cattle in a restricted zone of Argentina, northwest of Buenos Aires and southeast of Cordoba (Rizzo et al 1997).…”

Assessment of airborne Asteraceae pollen in Brisbane, Australia

“…B. halimifolia is an aggressive pioneer plant species that can rapidly colonize disturbed environments due to physiological adaptations that facilitate growth in saline and acidic soils (Parsons and Cuthbertson 2001). The species is also resistant to livestock herbivory due to the production of various intracellular toxins (Tokarnia et al 1992;Stegelmeier et al 2009). As a result of these invasive attributes, the Queensland Government has recognized B. halimifolia as a threat to the sustainability of agriculture and other land uses in Queensland (Wilson 2008).…”