Veterinary Services

Viral-type pneumonia was the likely cause of death of a 15-week-old gilt. There were three deaths in one pen in the previous three to four days. Affected pigs were found on their sides shaking and kicking. They were receiving penicillin in feed and the gilt had received amoxycillin. The right cranial lung lobe was dark purple and consolidated and there were multiple haemorrhages in the dorsal aspect of the right diaphragmatic lung lobe. No organisms were isolated in culture from the lung.  The histopathological findings in the lungs were consistent with an acute viral-type pneumonia. Though the changes were non-specific, the degenerative changes in the epithelium were suggestive of swine influenza. However, real time RT-PCR for Influenza A virus (including pandemic H1N1 2009) was negative.

Alimentary tract disorders

Severe viral-type enteropathy was diagnosed in two-week-old, Duroc-cross piglets with a scour problem. The scour was reported to commence at ten days of age and over 50 per cent of the piglets in a litter were affected although only occasional litters were involved. The sows were vaccinated against E.coli. Piglets were receiving toltrazuril at four days of age. There was no response to spectinomycin treatment. One of four piglets was positive for type C rotavirus in the PAGE test. No coccidia or cryptosporidia were detected in any of the four piglets. Histopathological findings suggested that rotavirus could be the cause. There was no evidence of bacterial involvement.

Concurrent infections with Lawsonia intracellularis and Brachyspira hyodysenteriae were diagnosed in an outbreak of diarrhoea in growing pigs. Another finishing unit reported three deaths and diarrhoea in a group of 80 pigs due to swine dysentery. A group B Salmonella species was isolated in culture from the intestinal contents of eight-week-old weaners with a history of diarrhoea. Sporadic cases of intestinal torsion and gastric ulceration were encountered.

Musculoskeletal disorders

Polyarthritis due to infection with Mycoplasma hyorhinis was diagnosed in 12 to 13-week-old large white cross Landrace gilts. Pigs in the affected group were exhibiting stiffness, lameness, knuckling and squealing when standing. Two gilts submitted for investigation were found to have excess reddish-brown fluid in the synovial joints, from which Mycoplasma hyorhinis was isolated.