Dr Andrew Tucker – Charles Street Veterinary Consultancy
Pasteurella multocida is a bacteria that can colonise existing lung lesions, increase their severity, resulting in pneumonic pastuerellosis. P. multocida pneumonia is difficult to reproduce experimentally unless there are already existing lung lesions such as those caused by A. pleuropneumoniae (APP) and M. hyopneumoniae (Mycoplasma). Pastuerellosis is transmitted by aerosol, contact and ingestion and is most common under poor husbandry conditions like overcrowding, dusty or ammoniacal atmospheres etc.How do you know if it’s on your farm?
Pastuerella affects predominantly the grower phase but can also affect the breeding herd. It is often more prevalent after a stress incident like mixing, weighing or transport. Affected pigs may be lethargic and show difficult breathing (abdominal type breathing), coughing, nasal discharge, fever and cyanosis of the extremities. Clinical signs often last for five to ten days and may end in recovery or death. Recovered pigs often remain thin.
Clinical signs, post mortem and histological findings suggest the presence of P. multocida and this can then be confirmed by culture of the organism.
How do you treat or prevent it?
Severely affected pigs should be treated by antibiotic injection, type dependant on the on-farm situation. Euthenasia should be carried out on collapsed and severely congested pigs as well as thin pigs with severe respiratory distress. Water and in-feed medication can both be used at specific times as part of a medication plan.
One of the most effective ways of controlling this disease is by implementing an all-in all-out system to reduce the spread of disease. Controlling the predisposing pathogen like M.hyopneumoniae is also very important. Lastly, husbandry conditions such as stocking density should be improved and dust and ammoniacal levels reduced.
Pig Diseases – D.J. Taylor; Diseases of Swine – Straw, Zimmerman, D’Allaire, Taylor