Zearalenone intoxication of pigs

Mycotoxicosis due to ingestion of zearalenone was detected on 2 pig farms on the Atherton Tableland in northern Queensland. In one herd of 200 pigs, this resulted from feeding maize which had been stored with a high moisture content. In the other herd of 1400 pigs, it resulted from feeding sorghum grain which was rain affected before harvest. Concentrations of zearalenone in the feeds ranged up to 8 mg/kg. Most prepubertal gilts in the herds displayed enlarged teats and signs of oestrus such as having red, swollen vulvas. In several cases both rectal and vaginal prolapses occurred. On one of the farms, 25 pigs died as a direct result of prolapses. Autopsy of a 3-monthold gilt revealed apparently enlarged ovaries and uterine horns. Sows and boars seemed to be unaffected. Four gilts failed to conceive following mating during the period of zearalenone ingestion, but apart from this and the deaths from prolapses, production of the herds appeared ti be unaffected.

Detection of Chlamydiaceae DNA in veterinary specimens using a family-specific PCR

Aims: The aim of this work was to develop a rapid molecular test for the detection of the Chlamydiaceae family, irrespective of the species or animal host. Methods and Results: The method described herein is a polymerase chain reaction targeting the 16S rRNA gene of the Chlamydiaceae family, and the results demonstrate that the test reacts with five reference Chlamydiaceae but none of the 19 other bacterial species or five uninfected animal tissues tested. The results also indicate the enhanced sensitivity of this test when compared with conventional culture or serology techniques. This is demonstrated through parallel testing of six real clinical veterinary cases and confirmatory DNA sequence analysis. Conclusions, Significance and Impact of the Study: This test can be used by veterinary diagnostic laboratories for rapid detection of Chlamydiaceae in veterinary specimens, with no restriction of chlamydial species or animal host. The test does not differentiate chlamydial species, and if required, speciation must be carried out retrospectively using alternate methods. However, for the purpose of prescribing therapy for chlamydiosis, this test would be an invaluable laboratory tool.

Global trade in ornamental fish from an Australian perspective: The case for revised import risk analysis and management strategies

Over 1 billion ornamental fish comprising more than 4000 freshwater and 1400 marine species are traded internationally each year, with 8-10 million imported into Australia alone. Compared to other commodities, the pathogens and disease translocation risks associated with this pattern of trade have been poorly documented. The aim of this study was to conduct an appraisal of the effectiveness of risk analysis and quarantine controls as they are applied according to the Sanitary and Phytosanitary (SPS) agreement in Australia. Ornamental fish originate from about 100 countries and hazards are mostly unknown; since 2000 there have been 16-fold fewer scientific publications on ornamental fish disease compared to farmed fish disease, and 470 fewer compared to disease in terrestrial species (cattle). The import quarantine policies of a range of countries were reviewed and classified as stringent or non-stringent based on the levels of pre-border and border controls. Australia has a stringent policy which includes pre-border health certification and a mandatory quarantine period at border of 1-3 weeks in registered quarantine premises supervised by government quarantine staff. Despite these measures there have been many disease incursions as well as establishment of significant exotic viral, bacterial, fungal, protozoal and metazoan pathogens from ornamental fish in farmed native Australian fish and free-living introduced species. Recent examples include Megalocytivirus and Aeromonas salmonicida atypical strain. In 2006, there were 22 species of alien ornamental fish with established breeding populations in waterways in Australia and freshwater plants and molluscs have also been introduced, proving a direct transmission pathway for establishment of pathogens in native fish species. Australia's stringent quarantine policies for imported ornamental fish are based on import risk analysis under the SPS agreement but have not provided an acceptable level of protection (ALOP) consistent with government objectives to prevent introduction of pests and diseases, promote development of future aquaculture industries or maintain biodiversity. It is concluded that the risk analysis process described by the Office International des Epizooties under the SPS agreement cannot be used in a meaningful way for current patterns of ornamental fish trade. Transboundary disease incursions will continue and exotic pathogens will become established in new regions as a result of the ornamental fish trade, and this will be an international phenomenon. Ornamental fish represent a special case in live animal trade where OIE guidelines for risk analysis need to be revised. Alternatively, for countries such as Australia with implied very high ALOP, the number of species traded and the number of sources permitted need to be dramatically reduced to facilitate hazard identification, risk assessment and import quarantine controls. Lead papers of the eleventh symposium of the International Society for Veterinary Epidemiology and Economics (ISVEE), Cairns, Australia

A one-tube fluorescent assay for the quarantine detection and identification of Tilletia indica and other grass bunts in wheat

A molecular assay with enhanced specificity and sensitivity has been developed to assist in the surveillance of Karnal bunt, a quarantineable disease with a significant impact on international trade. The protocol involves the release of DNA from spores, PCR amplification to enrich Tilletia-specific templates from released DNA and a five-plex, real-time PCR assay to detect, identify and distinguish T. indica and other Tilletia species (T. walkeri, T. ehrhartae, T. horrida and a group comprising T. caries, T. laevis, T. contraversa, T. bromi and T. fusca) in wheat grains. This fluorescent molecular tool has a detection sensitivity of one spore and thus bypasses the germination step, which in the current protocol is required for confirmation when only a few spores have been found in grain samples. The assay contains five dual-labelled, species-specific probes and associated species-specific primer pairs in a PCR mix in one tube. The different amplification products are detected simultaneously by five different fluorescence spectra. This specific and sensitive assay with reduced labour and reagent requirements makes it an effective and economically sustainable tool to be used in a Karnal bunt surveillance program. This protocol will also be valuable for the identification of some contaminant Tilletia sp. in wheat grains.

Enhanced diagnostic platforms for Post Entry Quarantine (PEQ)

Enhanced diagnostic platforms for Post Entry Quarantine (PEQ) and market access (Phase 1).

Improved Post Entry Quarantine Diagnostics

Develop a new diagnostic platform for Post Entry Plant Quarantine to support the detection of Emergency Plant Pests in the Australian Grains and Nursery Industries.

Post Entry Plant Quarantine

The seeds of the majority of commercial crops must be grown for one generation in post-entry plant quarantine on arrival in Australia. Live plants and cuttings must also undergo quarantine screening on arrival, and spend a minimum of three months in quarantine.

Significant features of the epidemiology of equine influenza in Queensland, Australia, 2007.

An outbreak of equine influenza (EI) caused by influenza A H3N8 subtype virus occurred in the Australian states of Queensland and New South Wales in August 2007. Infection in the Australian horse population was associated with the introduction of infection by horses from overseas. The first case of EI in Queensland was detected on 25 August 2007 at an equestrian sporting event. Infection subsequently spread locally and to other clusters through horse movements prior to the implementation of an official standstill. There were five main clusters of infected properties during this outbreak and several outliers, which were investigated to find the potential mechanism of disease spread. To contain the outbreak, Queensland was divided into infection status zones, with different movement controls applied to each zone. Vaccination was implemented strategically in infected areas and within horse subpopulations. Control and eventual eradication of EI from Queensland was achieved through a combination of quarantine, biosecurity measures, movement control, rapid diagnostic testing and vaccination.

Risk-based surveillance for avian influenza control along poultry market chains in South China: The value of social network analysis.

Over the past two decades, the poultry sector in China went through a phase of tremendous growth as well as rapid intensification and concentration. Highly pathogenic avian influenza virus (HPAIV) subtype H5N1 was first detected in 1996 in Guangdong province, South China and started spreading throughout Asia in early 2004. Since then, control of the disease in China has relied heavily on wide-scale preventive vaccination combined with movement control, quarantine and stamping out. This strategy has been successful in drastically reducing the number of outbreaks during the past 5 years. However, HPAIV H5N1 is still circulating and is regularly isolated in traditional live bird markets (LBMs) where viral infection can persist, which represent a public health hazard for people visiting them. The use of social network analysis in combination with epidemiological surveillance in South China has identified areas where the success of current strategies for HPAI control in the poultry production sector may benefit from better knowledge of poultry trading patterns and the LBM network configuration as well as their capacity for maintaining HPAIV H5N1 infection. We produced a set of LBM network maps and estimated the associated risk of HPAIV H5N1 within LBMs and along poultry market chains, providing new insights into how live poultry trade and infection are intertwined. More specifically, our study provides evidence that several biosecurity factors such as daily cage cleaning, daily cage disinfection or manure processing contribute to a reduction in HPAIV H5N1 presence in LBMs. Of significant importance is that the results of our study also show the association between social network indicators and the presence of HPAIV H5N1 in specific network configurations such as the one represented by the counties of origin of the birds traded in LBMs. This new information could be used to develop more targeted and effective control interventions.

Australia's newest quarantine for biological control

The paper describes the QC3 quarantine facility and supporting infrastructure which were purpose built for weed biological control at the Ecosciences Precinct. The quarantine is one of two new weed quarantine facilities in Australia and will service northern Australia. An account of the sharing philosophy between CSIRO and the Queensland Government and the necessity of working very closely with architects, project managers, builders and quarantine personnel is also given. This philosophy contributed to certification of the facility without any undue delays.

Fluoroquinolone-resistant extraintestinal pathogenic Escherichia coli, including O25b-ST131, isolated from faeces of hospitalized dogs in an Australian veterinary referral centre

To determine rates of carriage of fluoroquinolone-resistant Escherichia coli and extraintestinal pathogenic E. coli (ExPEC) among dogs in a specialist referral hospital and to examine the population structure of the isolates. Fluoroquinolone-resistant faecal E. coli isolates (n232, from 23 of 123 dogs) recovered from hospitalized dogs in a veterinary referral centre in Sydney, Australia, over 140 days in 2009 were characterized by phylogenetic grouping, virulence genotyping and random amplified polymorphic DNA (RAPD) analysis. The RAPD dendrogram for representative isolates showed one group B2-associated cluster and three group D-associated clusters; each contained isolates with closely related ExPEC-associated virulence profiles. All group B2 faecal isolates represented the O25b-ST131 clonal group and were closely related to recent canine extraintestinal ST131 clinical isolates from the east coast of Australia by RAPD analysis. Hospitalized dogs may carry fluoroquinolone-resistant ExPEC in their faeces, including those representing O25b-ST131.

Low-dose methyl bromide fumigation as a quarantine disinfestation treatment for nectarines against Queensland fruit fly (Diptera:Tephritidae)

White nectarines (Prunus persica var. nucipersica) were fumigated with methyl bromide (MB) at a nominal treatment dose of 18 g m-3 at 18°C for 5 h and 30 min as a quarantine disinfestation treatment against Bactrocera tryoni, the Queensland fruit fly. Three large scale trials were conducted against each of the four immature lifestages, eggs and first, second and third instars. There were no survivors from the estimated 43,614 eggs, 41,873 first instars, 41,345 second instars and 33,549 third instars treated, thereby resulting in an efficacy of GROTERDAN99.99% mortality at the 95% confidence level for each lifestage. Of the 12 trials reported herein, the highest concentration of MB, sampled from the chamber headspace analysed by gas chromatography, was 18.7 g m-3. The maximum chamber temperature from 5 min readings was 19.7°C and the maximum fruit core temperature was 19.5°C. The treatment time for all trials was exactly 5.5 h. Thus the recommended treatment dose to disinfest nectarines from B. tryoni is 19.0 g m-3 MB at 20.0°C for 5.5 h. Fruit quality trials were conducted on white nectarines at three combinations of treatment parameters: 15 g m-3 MB at 19°C for 5.25 h; 18 g m-3 MB at 19°C for 5.5 h and 21 g m-3 MB at 19°C for 5.5 h. The fruit were stored at 0, 4 and 8 days at 4°C and 8 days at 4°C followed by 4 d at 22°C. They were then were assessed for skin colour, flesh colour, skin defects, flesh defects, fruit weight loss, flesh firmness, total soluble solids, titratable acidity and rots. There was no significant difference between untreated control and MB treated fruits in any of the parameters measured. Thus the treatments did not have adverse effects on fruit quality.

Ecology of uncultivated oscillospira species in the rumen of cattle, sheep, and reindeer as assessed by microscopy and molecular approaches

The ecology of the uncultured, but large and morphologically conspicuous, rumen bacterium Oscillospira spp. was studied. Oscillospira-specific 16S rRNA gene sequences were detected in North American domestic cattle, sheep from Australia and Japan, and Norwegian reindeer. Phylogenetic analysis of the sequences obtained allowed definition of three operational taxonomic units within the Oscillospira clade. Consistent with this genetic diversity, we observed atypical smaller morphotypes by using an Oscillospira-specific fluorescence in situ hybridization probe. Despite the visual disappearance of typical large Oscillospira morphotypes, the presence of Oscillospira spp. was still detected by Oscillospira-specific PCR in the rumen of cattle and sheep. These observations suggest the broad presence of Oscillospira species in various rumen ecosystems with the level, and most likely the morphological form, dependent on diet. An ecological analysis based on enumeration of the morphologically conspicuous, large-septate form confirms that the highest counts are associated with the feeding of fresh forage diets to cattle and sheep and in two different subspecies of reindeer investigated.