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Foot-and-mouth disease (FMD) is a highly contagious viral disease of cloven-hooved animals. Global outbreaks have highlighted the significant economic, trade, psychosocial and animal welfare impacts that can arise from the detection of disease in previously 'FMD-free' countries. Rapid and early diagnosis provides significant advantages in disease control and minimization of deleterious consequences. We describe the process of further development and validation of a reverse-transcription loop-mediated isothermal amplification foot-and-mouth disease virus (RT-LAMP-FMDV) test, using a published LAMP primer set, for use in the field. An internal positive control (IPC) was designed and introduced for use with the assay to mitigate any intrinsic interference from the unextracted field samples and avoid false negatives. Further modifications were included to improve the speed and operability of the test, for use by non-laboratory trained staff operating under field conditions, with shelf-stable reaction kits which require a minimum of liquid handling skills. Comparison of the assay performance with an established laboratory-based real-time reverse transcriptase PCR (rRT-PCR) test targeting the 3D region of FMD virus (Tetracore Inc) was investigated. LAMP has the potential to complement current laboratory diagnostics, such as rRT-PCR, as a preliminary tool in the investigation of FMD. We describe a strategic approach to validation of the test for use in the field using extracted RNA samples of various serotypes from Thailand and then finally unextracted field samples collected from FMD-suspected animals (primarily oral lesion swabs) from Bhutan and Australia. The statistical approach to validation was performed by Frequentist and Bayesian latent class methods, which both confirmed this new RT-LAMP-FMDV test as fit-for-purpose as a herd diagnostic tool with diagnostic specificity >99% and sensitivity 79% (95% Bayesian credible interval: 65, 90%) on unextracted field samples

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Little is known of the prevalence of Cryptosporidium and Giardia parasites in sheep and the genotypes that they harbor, although potentially sheep may contribute significantly to contamination of watersheds. In the present study, conducted in Western Australia, a total of 1,647 sheep fecal samples were screened for the presence of Cryptosporidium and Giardia spp. using microscopy, and a subset (n = 500) were screened by PCR and genotyped. Analysis revealed that although both parasites were detected in a high proportion of samples by PCR (44% and 26% for Giardia and Cryptosporidium spp., respectively), with the exception of one Cryptosporidium hominis isolate, the majority of isolates genotyped are not commonly found in humans. These results suggest that the public health risk of sheep-derived Cryptosporidium and Giardia spp. in catchment areas and effluent may be overestimated and warrant further investigation.

In a survey of internal parasites in sheep at slaughter, high worm egg counts were found in a large proportion of lamb lines, suggesting significant production loss. Counts were lower in adult sheep, but were also significant in many lines. The protozoal parasites Giardia and Cryptosporidium were also commonly detected. Scouring was observed in some lines, and although not clearly related to parasitic infections, worm infections remain the most likely cause. It appears that many producers are not aware of the potential loss due to parasites in sheep intended for slaughter, and further investigation is required into the extent of losses and methods of prevention.

Enteric disorders are common in sheep and have major economic consequences attributable to dags, production losses and mortalities. The purpose of this paper is to provide a review of non-infectious intestinal conditions in sheep with an emphasis on the role of nutrition and the effects of various nutritional factors. The principles of treatment and prevention are discussed, but not reviewed in detail. Non-infectious causes of scouring in sheep are generally not well understood. In particular, the role of various nutritional factors in determining faecal consistency (in both the presence and absence of infectious agents) warrants further investigation. Nutritional manipulation may provide options for management and prevention of scouring in sheep.