Immunology/Virology of Respiratory Pathogens in Bovine Medicine

Bovine respiratory disease (BRD) is a multifactorial complex resulting from factors including aspects of the host response.  While research has historically focused on the relationship between naïve immune status and BRD risk, recent investigations indicate that excessive inflammatory response to infection may also contribute substantially to BRD.  Evidence suggests that activation of pro-resolving pathways is related to BRD resistance in recently weaned beef calves.  Intriguing findings of recent studies indicate that probiotics and prebiotics may modulate respiratory inflammation or resistance.  Activation of “trained” innate immunity may be a method by which nonspecific respiratory immunity may be stimulated; however, the possibilities and limitations of trained immunity have yet to be fully defined. This presentation will review these new developments in the context of BRD in beef cattle and dairy calves.