Isolation and characterization of Staphylococcus saprophyticus responsible for death of two six- banded armadillos (Euphractus sexcinctus)

Abstract

Abstract Two six-banded armadillos (Euphractus sexcinctus) suddenly died in a zoo of Nanjing, Jiangsu province, China, after exhibiting weak breath, high temperature, and nasal bleeding. Autopsy revealed dark brown appearance and enlargement of the visceral organs and several granular white necrotic foci in the spleen and liver of the two armadillos. Histological analysis revealed serious congestion, haemorrhage, and multiple necrotic foci in the spleen and liver; lungs exhibited congestion. Moreover, the bacterium suspected to be responsible for the death of the armadillos was observed in the spleen and lung tissue samples. Several gram-positive cocci were observed in the contacting smears of liver tissue samples. Biochemical analysis revealed that the isolated bacterium was Staphylococcus saprophyticus and was designated as S.S NH2021; 16S rRNA and gap gene sequencing of the isolate provided similar findings. Strain S.S NH2021 was resistant only against penicillin. Moreover, the mice challenged with high load of the isolated bacterium died and exhibited histopathological changes similar to those observed in the armadillos. To the best of our knowledge, this is the first report on S. saprophyticus infection in armadillos. This study provides a reference for breeding and management of six-banded armadillos in zoos.