Update on bacterial pathogenesis in BRD.
Mannheimia haemolytica, Pasteurella multocida, Histophilus somni, Mycoplasma bovis and Arcanobacterium pyogenes are all frequently implicated in bovine respiratory disease (BRD). M. haemolytica is considered the most important of the group. These bacteria are commensals in the nasopharynx and establish infection in the lungs of cattle that are subjected to a variety of stresses. Factors that permit adherence to and proliferation in the lungs and factors that cause tissue destruction and inflammation have been identified as having major roles in pathogenesis. These virulence factors include protein adhesins, capsular polysaccharide, outer membrane proteins, iron-binding proteins, lipopolysacharide or lipooligosaccharide, enzymes and toxins. These bacterial products function to evade the immune system, damage the immune system and induce a severe inflammatory response.
Confer
Anthony W
AW
Department of Veterinary Pathobiology, Center for Veterinary Health Sciences, Oklahoma State University, Stillwater, OK 74078-2007, USA. anthony.confer@okstate.edu
D000193:Actinomycetales Infections / Q000662:veterinary; D000818:Animals; D055667:Arcanobacterium; D048090:Bovine Respiratory Disease Complex / Q000276:immunology / Q000382:microbiology*; D002417:Cattle / Q000382:microbiology; D016978:Mannheimia haemolytica; D009175:Mycoplasma Infections / Q000662:veterinary; D045682:Mycoplasma bovis; D010326:Pasteurella Infections / Q000662:veterinary; D016979:Pasteurella multocida; D015661:Pasteurellaceae; D048089:Pneumonia of Calves, Enzootic / Q000382:microbiology