Contagious bovine pleuropneumonia (CBPP) is an insidious
pneumonic disease of cattle sometimes referred to as lung
sickness. Clinically, CBPP is manifested by anorexia, fever
and respiratory symptoms such as dyspnoea, cough and nasal
discharges. CBPP is found in the acute, subacute and chronic
forms. The disease is characterized by the presence of sero-fibrinous
interlobular oedema and hepatization giving a marbled appearance
of the lung in acute to subacute cases, and capsulated lesions
(sequestra) in the lungs of some chronically infected cattle.
Joint infections are common in calves.
The causative agent
of CBPP is Mycoplasma mycoides subspecies mycoides small colony
variant (MmmSC). Phylogenetically, the organism is a member
of the Mycoplasma mycoides cluster which are pathogens of
ruminants and include M. mycoides subsp. mycoides large colony
(LC), M. mycoides subsp. capri, M. capricolum subsp. capripneumoniae,
M. capricolum subsp. capricolum and Mycoplasma bovine group
7, an unnamed group of bovine mycoplasma isolates. The occurrence
of subacute symptomless infections and chronic carriers after
the clinical phase of the disease, create major problems in
the control of this disease.
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