Porcine deltacoronavirus (PDCoV) was first identified in Hong Kong in 2009-2010 and reported in United States swine for the first time in February 2014. However, diagnostic tools other than polymerase chain reaction for PDCoV detection were lacking and Koch's postulates had not been fulfilled to confirm the pathogenic potential of PDCoV. In the present study, PDCoV peptide-specific rabbit antisera were developed and used in immunofluorescence and immunohistochemistry assays to assist PDCoV diagnostics. The pathogenicity and pathogenesis of PDCoV was investigated following orogastric inoculation of 5-day-old piglets with a plaque-purified PDCoV cell culture isolate (3 × 10(4) TCID50 per pig). The PDCoV-inoculated piglets developed mild to moderate diarrhea, shed increasing amount of virus in rectal swabs from 2 to 7 days post inoculation, and developed macroscopic and microscopic lesions in small intestines with viral antigen confirmed by immunohistochemistry staining. This study experimentally confirmed PDCoV pathogenicity and characterized PDCoV pathogenesis in neonatal piglets.

, 10 ml per pig.All three PEDV prototype isolates tested in this study, regardless of their phylogenetic clades, had similar pathogenicity and caused severe enteric disease in 5-day-old pigs as evidenced by clinical signs, faecal virus shedding, and gross and histopathological lesions. Compared with pigs inoculated with the three US PEDV prototype isolates, pigs inoculated with the S-INDEL-variant isolate had significantly diminished clinical signs, virus shedding in faeces, gross lesions in small intestines, caeca and colons, histopathological lesions in small intestines, and immunohistochemistry staining in ileum. However, the US PEDV prototype and the S-INDEL-variant strains induced similar viraemia levels in inoculated pigs. Whole genome sequences of the PEDV prototype and S-INDEL-variant strains were determined, but the molecular basis of virulence differences between these PEDV strains remains to be elucidated using a reverse genetics approach.

Bovine tuberculosis of cattle results primarily from infection with Mycobacterium bovis, a member of the Mycobacterium tuberculosis complex. Despite intensive control efforts, bovine tuberculosis persists as a costly disease, with adverse impacts on animal health and welfare, the trade of animals and animal products, and the livelihoods of producers. In addition, the persistence of this disease necessitates the maintenance of costly regional and federal networks for control/eradication campaigns. The mainstays of bovine tuberculosis control are (i) abattoir surveillance with epidemiological investigations after detection of M. bovisinfected animals, to identify bovine tuberculosis-affected herds (1); (ii) application of antemortem testing for routine surveillance, movement of animals, and identification and removal of infected animals from tuberculosis-affected herds (2); and (iii) management of the disease in wildlife reservoirs, such as whitetailed deer in Michigan (3), brushtail possums (Trichosurus vulpecula) in New Zealand, Eurasian wild boar (Sus scrofa) and red deer (Cervus elaphus) in Spain (4), and Eurasian badgers (Meles meles) in the United Kingdom/Ireland (5). Tuberculin-based cellular immune assays, including measurements of in vitro interferon gamma release and measurements of delayed-type hypersensitivity (DTH) reactions via skin test procedures, are the principal diagnostic tests used for the control of bovine tuberculosis in cattle in most countries (6, 7). In the United States, the caudal fold test (CFT) (intradermal injection of M. bovis purified protein derivative [PPD] in the caudal skin fold) is used as a primary test and the comparative cervical test (CCT) (intradermal injection of Mycobacterium avium and M. bovis PPDs at separate sites in the neck) and the Bovigam assay (Prionics Ag, Schlieren, Switzerland) (an interferon gamma release assay) are used as secondary or confirmatory tests (8).Several serological tests designed to detect antibodies (Abs) to immunodominant M. bovis antigens (e.g., MPB83, MPB70, ESAT-6, and CFP10) have emerged for potential application in cattle (9-13). A commercial enzyme-linked immunosorbent assay (ELISA) for MPB83 and MPB70 (M. bovis Ab test; IDEXX Laboratories, Westbrook, ME) (9) has been approved by the Office International des Epizooties and the U.S. Department of Agriculture (USDA) for use in cattle in bovine tuberculosis control programs, although applications of this test are primarily limited to ancillary purposes such as confirmation of infections and potentially detection of M. bovis-infected cattle anergic in the skin test. A