Plasma antibacterial activities in ornate (Terrapene ornata) and eastern box turtles (Terrapene carolina). Issue 5 (10th February 2020) - Adamovicz, Laura
Abstract: Chelonians are one of the most imperiled vertebrate taxa and many species are increasingly threatened by disease, however, the immune response in this group is understudied. We quantified the innate immune response of eastern ( Terrapene carolina ; EBT) and ornate ( Terrapene ornate; OBT) box turtles using plasma antibacterial activity assays. Plasma from both species abolished or significantly reduced the growth of all eight bacterial species evaluated, including Salmonella typhimurium, Escherichia coli, Enterobacter cloacae, Citrobacter freundi, Bacillus subtilis, Staphylococcus epidermidis, and Staphylococcus aureus . Bactericidal capacity was greater in OBT compared to EBT, and OBT plasma retained high antibacterial activities at a broader temperature range (20–40°C) compared to EBT (30–40°C). Plasma antibacterial activity was abolished following treatment with heat, protease, and ethylenediaminetetraacetic acid, indicating that complement is likely responsible for the observed effects. Further characterization of the box turtle immune response may provide insight into the importance of infectious diseases for species conservation, enabling the development of more efficient and effective population management strategies. Abstract : Effects of temperature on the antibacterial activities of plasma from ornate box turtles (OBT; Terrapene ornata ) and eastern box turtles (EBT; Terrapene carolina ) against Escherichia coli . Results represent the means ± standard deviations for six replicates. Asterisks indicate values significantly different from the peak value for each species ( p < .05). Research Highlights: Box turtle plasma has rapid, robust bactericidal activity OBT have higher antibacterial capacity across wider temperatures versus EBT Antibacterial activity is abolished with heat, protease, and EDTA, consistent with a complement‐mediated process