Short communication: preliminary observations on the serum levels of HSP70 and its correlation with serum cortisol, thyroid hormones, and acute-phase protein concentration in cattle naturally infected with foot-and-mouth disease virus

The study aimed to explore the serum levels of HSP70 and identify its possible association with serum cortisol, thyroid hormones, and acute-phase protein concentrations in cattle naturally infected with foot-and-mouth disease (FMD) virus. After the FMD outbreak in an organized dairy cattle farm in India, blood samples were obtained from clinically infected (n = 40) and apparently healthy (n = 30) animals. Samples were processed and tested by an in-house DIVA assay for confirmation of FMD infection. Serum was analyzed for HSP70, cortisol, T4, T3, haptoglobin, and serum amyloid A by enzyme-linked immunosorbent assay (ELISA). HSP70 concentrations were significantly higher in the serum of clinically infected cattle (p < 0.01) than the healthy group. To the best of our knowledge, this is the first report describing the elevated serum levels of HSP70 under infectious diseases of bovines. Cortisol (p < 0.05), haptoglobin (p < 0.001), and serum amyloid A (p < 0.05) concentrations also markedly increased in the diseased animals; however, no differences (p > 0.05) were found in T4 and T3 levels between healthy and infected cattle. Elevated HSP70 concentration correlated positively with high cortisol (p < 0.05) and haptoglobin (p < 0.001) levels suggesting an essential link between these acute events during clinical infectious phase of FMD.