Contagious bovine pleuropneumonia
Contagious bovine pleuropneumonia (CBPP) is a very important infectious disease of cattle in tropical Africa.
This disease can result to mortality reaching 80% in a naive herd.
Many cattle that survive will eventually become carriers. Uninfected herd may get the infection from the carriers.
Contagious bovine pleuropneumonia is caused by Mycoplasma mycoides subsp. mycoides, Usually the small colony type.
Cattle and buffalo are the primary hosts for M. mycoides SC.
M. mycoides SC is mainly transmitted from animal to animal in respiratory aerosols.
The organism can be found in saliva, urine, fetal membranes and uterine discharges of infected animal.
Close contact is necessary for transmission but M. mycoides SC might be spread over longer distances under favourable climatic conditions.
Carrier animals can harbour the organisms in encapsulated lung lesions for several months or more which can be shed when stressed.
Clinical Signs
Acute cases in cattle are characterized by fever, loss of appetite, depression, drop in milk production.
Respiratory signs, which may include coughing, purulent or mucoid nasal discharges, and rapid breathing.
Severely affected cattle may stand with their head and neck extended and forelimbs apart, breathing through the mouth.
Severely affected cattle may die within 3 weeks.
A few cattle with CBPP may die peracutely with no clinical signs other than fever.
Diarrhoea, abortion and stillbirth have been reported.
In calves of about 6 months of age, it presents with arthritis. Respiratory signs may not be apparent. The affected joints may be so painful that the animal is very reluctant to bend them.
Chronic CBPP is characterized by recurrent fever, loss of condition, and respiratory signs that may be apparent only when the animal is exercised.
The organism is generally fragile in the environment.
They are susceptible to many disinfectants including 1% sodium hypochlorite, 70% ethanol, phenol based disinfectants, formaldehyde.
Outbreaks are eradicated with strict biosecurity measures including quarantines, movement controls, slaughter of infected and in-contact animals, and cleaning and disinfection ( see biosecurity )
Vaccines may be used to control CBPP in endemic areas.
Tetracycline and fluoroquinolones are effective in treating but may not eliminate the infection. Chronic cases may be resistant to antibiotic treatment.