VLA: Respiratory Problems Cause Losses

by 5m Editor
17 February 2011, at 9:17am

UK - Actinobacillus pleuropneumoniae, Glasser's disease and PCV/PRRS caused respiratory symptoms and losses on pig units, according to the Veterinary Laboratories Agency (VLA) Monthly Scanning Surveillance Report for November 2010.

Alimentary Tract Diseases


Salmonellosis due to a multi-resistant S. Typhimurium Copenhagen was diagnosed following necropsy of five, approximately six-week-old, rearing piglets from an all-in/all-out unit of 440. The pigs came onto the unit in early October. Prior to this, the unit had been free of pigs for 10 days following destocking and disinfection. The main clinical signs observed were scour and ill-thrift with some cases of sudden death. There was no evidence of concurrent viral infection with PRRS. Other pathogens isolated from the lung included Mycoplasma hyorhinis by DGGE and Haemophilus parasuis on culture.

Gastric ulcers

A two-year-old sow that had farrowed two weeks earlier became lethargic and anorexic and died the next day. Necropsy at RVC revealed pallor of the carcase and 'watery' blood. The stomach was distended by red-black fluid in which granular 'coffee-grounds'-like material was suspended. There was hyperkeratinisation of the epithelium of the pars oesophagea and an approximately 1-cm diameter ulcer, from which the bleeding was presumed to have originated.

Respiratory Diseases


Sutton Bonnington diagnosed pandemic swine influenza H1N1 (2009) in two eight- to nine-week-old piglets from a breeding-nursery unit. There were clinical signs of respiratory disease in about 50 per cent of 1,500 weaners, initially mild signs but becoming more severe as the outbreak progressed. Clinical signs included coughing, sneezing, ocular discharge, weight loss and laboured breathing. Most pig workers on the farm had flu-like symptoms at the time, which theoretically could have been a potential source of infection. An untypable Streptococcus suis was also isolated from the lungs of one piglet indicating secondary bacterial infection.

PCV-2 and PRRS

Bury diagnosed concurrent PCV-2 associated disease and PRRSV as the cause of coughing and wasting with malaise in 14-week-old pigs. Approximately 15 per cent of a group of 290 pigs were affected with 11 deaths on a single-sourced indoor nursery-finisher unit with a total of 460 pigs that had been performing well. Histopathology on lymph node, kidney and lung confirmed PCV-2 associated disease. The pig also tested positive for PRRSV by PCR; concurrent PRRSV infection is a recognised risk for more severe PCV-2 associated disease. Streptococcus suis type 7 was isolated from the kidney; the pig may well have been terminally septicaemic secondary to the viral infections. PCV-2 vaccination has now been instituted at weaning.

Actinobacillus pleuropneumoniae

Bury investigated sudden deaths and respiratory disease in 15-week-old finishers on a large single-sourced indoor finisher site. The problem had been going on for two to three weeks and five per cent post weaning mortality was reported. Portions of lung from three pigs were submitted on one of which there was evidence of overlying fibrinous pleurisy and from this lung Actinobacillus pleuropneumoniae was isolated. The other portions of lung showed areas of focal pulmonary consolidation suggestive of APP although this was not isolated; Pasteurella multocida was isolated from all three portions of lung. No evidence of PCV-2 associated disease was detected by histopathology on lymph node and lung, and no PRRSV or swine influenza virus involvement was detected.

Glasser's disease

Glasser's disease was diagnosed as the cause of a sudden upsurge of coughing, mortality and lethargy affecting 30 per cent of 740 21-week-old housed finishers on a well managed all-in/all-out unit. Affected boars showed marked oedematous scrotal enlargement. A generalised fibrinous pleurisy and pericarditis were detected at post mortem examination, consistent with Glasser's disease and Haemophilus parasuis was isolated from multiple sites. No PRRSV or swine influenza virus were detected and histopathology did not reveal involvement of PCV-2 associated disease.

Further Reading

- You can view the full report by clicking here.

Further Reading

- Find out more information on the diseases mentioned in this article by clicking here.

Further Reading

- Find out more information on PMWS by clicking here.

5m Editor