Review on Bovine Pneumonic Pasteurellosis

Abstract

Bovine pneumonic pasteurellosis is an economically important disease of cattle mainly in feedlot industry; and is characterized clinically by acute bronchopneumonia with toxemia. The bacteria have many virulence factors like capsule, fimbriae, endotoxin and leukotoxin. The disease is mostly associated with stress factors as the bacteria are commensals in the upper respiratory tract. The most common predisposing factors that expose cattle to bovine pneumonic pasteurellosis are transportation, the presence of concurrent bacterial, viral and parasitic disease, overstocking, any mass veterinary and animal husbandry practices like mass vaccination, prophylactic treatment, castration, docking, dehorning etc. Suddenly change of macro and micro climatic conditions, starvation and water deprivation of cattle can also expose the cattle to pneumonic pasteurellosis. Because they are stress factors that reduce the immune status of animals; as the result the commensal organism becomes pathogenic to stressed cattle and cause bovine pneumonic pasteurellosis. Bovine pneumonic pasteurellosis can be diagnosed by considering the epidemiology, clinical signs and the necropsy findings. However, confirmatory diagnose of bovine pneumonic pasteurellosis is done by isolation and identification of the causative agent from clinical specimens. Bovine pneumonic pasteurellosis must be differentiated from CBPP; Infectious Bovine Rhinotrachitis (IBRT), lung worms that have almost similar clinical findings. Treatment of the disease is effective in the early stage of the disease by using different antimicrobial drugs. However, the bacteria have many antimicrobial resistance factors and resistant to many antimicrobial drugs. The disease can be prevented and controlled by reducing stress factors, by improving management, by using antimicrobial drugs in their prophylactic treatment and using effective vaccines. But the presence of many serotypes and antimicrobial resistance factors of the organism make the disease difficult to prevent and control. So that reducing stress factors, performing qualitative antibiogram and using efficient vaccine which contains the major serotypes of Mannheimia haemolytica are crucial to control the disease.