Mycobacterium bovis vaccination and subsequent experimental infection outcomes are associated with changes in vitamin D status in dairy calves

Abstract

Graphical Abstract Summary: The study design incorporated 2 phases: the vaccination phase (weeks 0-52) and the experimental infection phase (weeks 52-65). Twenty-eight cattle younger than 8 weeks old were housed at APHA Weybridge throughout the study and fed a body weight-controlled diet. Twenty-two calves in total were included for statistical analyses. A mixed-effects logistic regression model was constructed using the nlme package within R, revealing that vitamin D (vitD) concentrations increased in vaccinates compared with nonvaccinates postinfection, with vaccinated animals reaching higher vitD levels than nonvaccinates by week 65. Linear regression analysis revealed a negative linear relationship between vitD concentration and pathology score irrespective of vaccination status. There was no correlation between interferon-γ cytokine production and vitD concentration. Results suggest that vitD may play a role in the reduction of pathology of bovine tuberculosis. Created with BioRender.com.