VLA: Proliferative and Necrotising Pneumonia

by 5m Editor
18 February 2011, at 9:16am

UK - Proliferative and necrotising pneumonia has been observed in 10 week old growing pigs, according to the Veterinary Laboratories Agency (VLA) Monthly Scanning Surveillance Report for December 2010.

Alimentary tract diseases


A breeding herd of 180 animals experienced an outbreak of neonatal diarrhoea. 90 per cent of gilt litters were affected with 10 per cent affected group mortality. Gross examination of one 3-day-old piglet revealed evidence of moderate catarrhal enteritis and severe dehydration. K88 (F4) positive E. coli were recovered from the intestinal contents (rotavirus negative).


Faeces samples were received from a unit experiencing a scour problem in 10-day-old piglets. Half of a group of 80 were affected with 12 deaths. Tests for enteropathogenic E. coli, Salmonella species and rotavirus were all negative. However coccidial oocysts (7,800 opg) were detected in one of the two samples suggesting that coccidiosis was the most likely cause of the scour.

Swine Dysentery

Thirsk necropsied three 17-week-old pigs as part of an investigation into an ongoing problem of sudden death in finishing pigs on a large farrow-to-finish unit. Post mortem examination revealed a marked typhlocolitis, confirmed as swine dysentery by the isolation of Brachyspira hyodysenteriae; in addition two of the three pigs had ulceration of the pars oesophagea of the stomach. The quality of the buildings was thought to have been a predisposing factor.

Respiratory Diseases

Swine Influenza

Bury diagnosed swine influenza by detection of virus in nasal swabs in fourweek- old weaners. Approximately 20 per cent of a group of 825 had shown signs of coughing and then meningitis, the same problem had been reported in the previous four batches of pigs from the same breeding unit. Concurrent Streptococcus suis and swine influenza infection has been noted in previous outbreaks and clinical findings suggested a similar situation on this farm. The swabs tested negative for pandemic H1N1 2009 influenza virus. Further identification of the virus is in progress.

Proliferative and Necrotising Pneumonia

Coughing was described over a two-week period in a batch of growers aged 10-weeks-old on an indoor rearing unit. Two fresh plucks were submitted to Bury for necropsy which revealed pneumonia in both, involving the middle lung lobes in one pluck and the left middle and caudal lung lobes in the other. Pasteurella multocida and Streptococcus suis type 2 were both isolated from the lungs, however more significantly, histopathology and immunohistochemistry revealed one lung to have marked proliferative and histiocytic bronchointerstitial pneumonia together with multiple small areas of necrotising alveolitis with significant labelling of tissues by immunohistochemistry for both PRRSV and PCV-2. These findings are consistent with proliferative and necrotising pneumonia (PNP) associated with combined PCV-2 and PRRSV infections.

Further Reading

- You can view the full report by clicking here.
- Find out more information on the diseases mentioned here by clicking here.

Further Reading

- Find out more information on PMWS by clicking here.

5m Editor