Enzootic calcinosis caused by Solanum glaucophyllumin cattle: retrospective analysis of 23 outbreaks in Central Argentina.

Enzootic calcinosis (EC) is a chronic disease mainly affecting ruminants consuming calcinogenic plants. In Argentina, EC is associated by the consumption of <i>Solanum glaucophyllum</i> in beef grazing cattle and is one of the most frequent toxicities affecting livestock from low-flooded areas. In this paper, we describe 23 outbreaks of EC in beef cattle due to consumption of <i>S. glaucophyllum</i> in central Argentina between 1990 to 2024. Outbreaks occurred more frequently during the summer-autumn (February-May) and affected more frequently adult beef cattle. An average morbidity and mortality of 13.75% and 4.22% were registered, respectively. The main clinical signs were progressive emaciation, limbs stiffness, and lameness. Necropsies were performed, and gross findings included multifocal-coalescent mineralization of blood vessels, heart, and lung. Microscopically, severe diffuse mineralization was observed mainly in the endocardium and intima and media layers of the aorta. Intra-alveolar mineralization was observed lining the wall of the alveolar septa, confirming calcium salt deposits by von Kossa staining. Blood calcium and phosphorus values in affected cattle remained within the reference ranges. Consumption of <i>S. glaucophyllum</i> was confirmed in all outbreaks. Despite being an endemic problem in the beef industry in Argentina, there are no effective treatments or control strategies, therefore, further studies are necessary to prevent the occurrence of EC.