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Post weaning multisystemic wasting syndrome (PMWS) was first described in young pigs in Western Canada in 1991, associated with porcine circovirus 2 (PCV2). Not all infected pigs develop PMWS and the virus is associated with numerous other diseases including porcine dermatitis and nephropathy syndrome (PDNS). PMWS occurs in 5 to 12-week-old pigs, which have wasting, ill thrift, with or without dyspnoea or jaundice, and occasionally pallor or diarrhoea. Morbidity may be up to 15% and mortality up to 80%. PDNS affects 7 to 20-week-old pigs, and includes cutaneous haemorrhages, lethargy and anorexic. Pigs have glomerulo- and interstitial nephritis and systemic necrotising vasculitis on histopathology. PCV2 occurs in Australia but no cases of PMWS have been reported, and only sporadic cases of PDNS. This study used clinical case material from six properties in New South Wales, three from Victoria and one from Queensland. A total of 22 pigs with clinical signs and gross pathology that could be consistent with PMWS or PDNS were fully investigated. Tests included histopathology and immunocytochemical identification of PCV2 antigens. Serological archive samples from 1114 pigs showed that there is widespread exposure to PCV2 and this has been present at least since 1995. Four cases of PDNS were identified in Victoria but there were no cases of PMWS. The authors note the small numbers of animals that were submitted, but pig veterinarians practising in New South Wales reported that they were not seeing clinical signs suggesting PMWS. Serological examination suggested that the virus was not widespread in feral populations, particularly in Northern Territory, but was common in New South Wales on the fringes of greater Sydney. Information about cattle feedlot entry is commonly collected but little has been published about Australian feedlot data. Bovine respiratory disease causes chronic pulmonary damage and inflammation and depression of dry matter intake, so has a marked effect on average daily weight gain. The study was performed on a 7000 head Queensland feedlot and included data on 2468 beef cattle weighing around 340 kg, studied on entry to the feedlot in winter 2004. This study shows that cattle with permanent incisors at time of feedlot entry had higher mean growth rates. The reason for this is unclear but may be due to the increased time since weaning, increased dominance of older cattle in the feedlot, or decreased dry matter intake because of the gingival inflammation and pain associated with eruption of teeth. Bos taurus cattle were more susceptible to bovine respiratory disease than Bos indicus, such as the Santa Gertrudis breed; Herefords were the most susceptible. Minimum temperature had a higher correlation to disease treatments than temperature range. The authors recommend further study of the associations between climate and incidence of bovine respiratory disease over the whole year, at multiple sites. As part of the trial for the Gudair® vaccine for the control of ovine Johne's disease, it had to be shown to reduce mortalities and the faecal shedding of Mycobacterium avium subspp paratuberculosis. As individual faecal tests are very expensive, pooled faecal culture was used. The aims of this study were to identify the most appropriate pooled faecal culture method for the trial and to develop a tool to perform prevalence calculations. A computer model was developed to compare seven methods of estimating the prevalence of Johne's disease from pooled test results. These methods relied on different assumptions about whether the pool size was fixed or variable, and whether the test sensitivity and specificity were perfect, imperfect or uncertain. The authors discuss the methods in detail and suggest that all performed well in most cases. They identified one method that gave accurate and reasonable estimates of the true prevalence and allowed for variable pool size. They note that these methods all underestimate the true prevalence of infection but can be used to estimate prevalence when individual faecal culture tests are not available. They concluded that more research is needed to develop a method that will take into consideration the variation in pool size, test sensitivity and specificity at different levels of pool size and prevalence, as well as with different proportions of multibacillary or pauibacillary sheep. Enzootic abortion of ewes comes from infection with Chlamydophila abortus, and infected sheep are antibody positive. Protocols for sheep export for breeding specify that all sheep must test negative in complement fixation tests. These have low specificity, and cross reactivity with other chlamydia species is common, so although Australia claims freedom from enzootic abortion, sera often give positive reactions. ELISAs are generally preferred to equivalent complement fixation assays as they are technically easier. There are no more antigen stocks for the previously used test, so this paper compared specificity and sensitivity of three complement fixation tests and four ELISAs, to find a suitable replacement assay to use for the export market. Methods were compared using 55 positive ovine samples obtained from experimentally infected sheep from the UK and 50 negative samples from New Zealand. Results showed that three of the ELISAs had similar specificity to one of the complement fixation tests, but only one, the POMP80-90, had suitable sensitivity and was commercially available. The authors note that its specificity of 86% is still not ideal and that the search for a more specific assay should continue. Radiographs of the right distal radius and carpus of a dog with mild weight bearing lameness after exercise showed the presence of an osteophyte and calcification of the medial radius and carpal bones. At surgery it was found that the abductor pollicus longus was trapped by the osteophyte, with the distal part buried in firm connective tissue, causing friction when the flexor carpi radialis moved during running. The osteophyte was surgically removed and the dog recovered over the succeeding 2 months. The role of glucosamine and collagen peptide in resolution of the lameness is unknown, but administration of these substances had no apparent effect on the degree of lameness prior to surgical intervention. Metatarsal rotation is recognised as a presumed inherited and/or congenital disease of large and giant breeds of dogs, and may result from an imbalance of muscular forces in the proximal metatarsus. Rotation can be close to 90 degrees, and if severe and bilateral the plantar surfaces of the hind paws can be apposed. In this case report, bilateral hind limb lameness in an 8-week-old St Bernard was attributed to the severe rotational abnormalities of both hind paws evident radiographically. Surgical correction involved arthrodesis of the left tarsus at 8 months of age, followed by arthrodesis of the right tarsus 6 months later. On both sides, an external circular fixator was used to stabilise the arthrodesis and was left in place for 3 to 4 months. The dog's gait was substantially improved at 13 months after completion of the surgery, and this method of treatment provides an alternative to euthanasia, usually recommended in cases of severe metatarsal rotation. Typical signs of hepatic encephalopathy (HE) in horses are depression, head pressing, circling and aimless wandering, and occur in 50% of horses with confirmed hepatic disease. In this case report of an 11-year-old pregnant mare with chronic active hepatitis and clinical signs of HE, classic histopathological signs of HE were present in the cerebrum of both the mare and fetus, suggesting that fetal CNS injury can occur secondary to HE in the mother. Although the mare responded initially to supportive therapy, the irreversible liver disease found at necropsy explained the subsequent deterioration of her condition when discharged from hospital. This is apparently the first report of equine fetal cerebral pathology consistent with HE occurring as a result of liver disease in the dam. The authors conclude that foals born to mares with a history of hepatic dysfunction during pregnancy should be closely monitored for signs of encephalopathy. Closure of larger fistulae resulting from comminuted fractures of the facial bones of the horse can be unsuccessful if there is excessive tension on, or an insufficient vascular supply to, the skin. In this case report an alternative method of repair is described in two horses with chronic sinocutaneous fistulae. In one of the horses two previous attempts at closure of the fistulae had failed. The repair used H-plasty bipedicle skin flaps and periosteal flaps to give a good cosmetic and functional outcome.

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