Clinical and laboratory findings in sheep experimentally poisoned by Palicourea marcgravii and the use of magnesium chloride with possible therapeutic effect on poisoning

Cunha I.M., Lessa D.A.B., Carvalho V.A.N., Alencar N.X., Teixeira A.L.S., Caldas S.A., Souza G.N. & Helayel M.J.SA. 2021. Clinical and laboratory findings in sheep experimentally poisoned by Palicourea marcgravii and the use of magnesium chloride with possible therapeutic effect on poisoning. Pesquisa Veterinaria Brasileira 41:e06931, 2021. Universidade Federal Fluminense, Av. Almirante Ary Parreiras 503, Santa Rosa, Niteroi, RJ 24230-340, Brazil. E-mail: isabellemedvet@gmail.com This study aimed to examine the efficacy of magnesium chloride therapy in sheep experimentally poisoned by Palicourea marcgravii and describe the clinical and laboratory findings that may aid in early ante mortem diagnosis of this poisoning. P. marcgravii is an important plant within a group of 22 species in Brazil that cause "sudden death." Its toxic component is sodium monofluoroacetate. It was observed that a time for evolution of poisoning was longer in our study compared to other studies that used the same dose of P. marcgravii in sheep. However, all animals that were poisoned and subsequently treated with magnesium chloride died. The sheep presented characteristic clinical signs before death in addition to other signs that have not been previously described for this type of poisoning, such as abdominal breathing, coughing, head pressing, and nystagmus. This is the first evaluation of hematological parameters of sheep poisoned by P. marcgravii. Leukocytosis with neutrophilia, hyperfibrinogenemia, and hyperglycemia, associated with hypophosphatemia and elevated levels of serum aspartato aminotransferase (AST), glutamate dehydrogenase (GLDH), urea, creatinine, creatine kinase (CK) and lactate dehydrogenase (LDH), were observed. Additionally, changes were noted in necropsy, such as engorged jugular, large vessel congestion, pulmonary edema. Histological examination revealed vacuolar hydropic degeneration in the distal twisted uriniferous tubules in the kidneys, similar to those reported in previous studies on P. marcgravii poisoning.