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Incidence of unusually high numbers of stillbirths was observed at a piggery unit at the Veterinary University research farm in Tamil Nadu State of India. Systematic examination of the tissue from stillborn piglets led to the identification of presence of Porcine circovirus 2 (PCV2). Detailed analysis utilizing electron microscopy, polymerase chain reaction and sequencing confirmed the presence of PCV2 in the tissue of affected piglets. Histopathology analysis of the affected piglet tissue showed lymphoid cell depletion of lymphnodes, spleen and infiltration of liver, kidney, myocardium, etc. Retrospective examination of the morbidity and mortality history in the farm revealed high mortality in young and weanling piglets suggestive of PCV2 infection-induced diseases. This is the first report of emergence of major disease incidence in farmed swine due to PCV2 infection in India.

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Infectious Bursal Disease (IBD) is a viral, contagious immunosuppressive disease posing an important threat to the commercial poultry industry. Evolution of highly virulent strains of IBD virus warranted the need for detailed characterization of the immune responses offered by the currently available vaccines. Two extensively used live vaccines of varied attenuation levels - intermediate and intermediate plus - strains were analyzed for the induction of immune responses. Both the vaccines induced protective antibody titers with the onset, quicker and higher with the intermediate plus vaccine. The intermediate plus strain vaccinate was observed to induce higher levels of IFN-γ in the birds. These results were supported by immunophenotype analyses with an increase in CD8+ and simultaneous decrease in CD4+ cell population. Both vaccine strains conferred protective immunity against virulent challenge. The study warrants the use of intermediate plus vaccines in disease endemic regions and intermediate vaccines in non-endemic regions to prevent IBD infection.

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Bluetongue is an infectious disease caused by bluetongue virus (BTV), which affects sheep, goat, cattle and certain wild ruminants. However severe clinical signs are usually seen with significant mortality in sheep than cattle and goat. To date, comparative studies on innate immune responses of sheep and goat infected with BTV is lacking. In this study, we compared the innate immune response of sheep and goat by infecting the peripheral blood mononuclear cells (PBMCs) with BTV serotype 23. In our study, we observed that sheep PBMCs supports higher virus replication than goat PBMCs. To delineate the role of innate immune response in differential viral replication observed in this study, we examined TLR3 (Receptor for dsRNA virus) mRNA expression and cytokine profiles (IL-1ß, Il-6, IL-8, Il-10, IL-12p40, TNF-α, IFN-γ and IFN-α) following Poly I:C (TLR3 ligand) stimulation and BTV 23 infection. In our present study, sheep PBMCs had significantly higher TLR3 mRNA levels, TLR3 specific ligand (Poly I:C) stimulation resulted in increased levels of IFN-γ at transcriptional and translational levels along with IL-8 and IL-10 at transcriptional levels. Whereas, the levels of TNF-α was higher in goat PBMCs at transcriptional levels. BTV infected sheep PBMCs expressed significantly higher levels of IFN-γ at transcriptional and translational levels along with IL-6, IL-8 and IL-10 at transcriptional levels. Whereas the expression levels of TNF-α and IFN-α at transcriptional and translational levels were significantly high in goat PBMCs. To examine the potential factor for consistent increase in the expression of TNF-α, we sequenced the promoter region of TNF-α and identified a total of five single nucleotide polymorphisms (SNP) and one indel in goat TNF-α promoter region. Luciferase assay for transcriptional activity of the promoter showed that goat TNF-α has significantly enhanced transcriptional activity in comparison with sheep TNF-α promoter. Altogether, our data suggests that the expression levels of TNF-α and IFN-α and/or IL-10 plays crucial role in replication of BTV 23.

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2,4-Dihydroxyacetophenone thiosemicarbazone (DAPT) forms a 1:1 complex with copper(II) which can be extracted into n-butanol or ethyl acetate from acetic acid-sodium acetate (pH 5.0) buffer, and a 1:1 nickel(II) complex which can be extracted into n-butanol from ammonium chloride-ammonia (pH 7.5) buffer. The difference between the pH(1 2 ) values for extraction of the two complexes is 3.4 and this has been exploited for their sequential extraction and determination. The molar absorptivities for the copper and nickel complexes are 1.5 x 10(4)l.mole(-1).cm(-1) at 390 nm and 8.2 x 10(3)l.mole(-1).cm(-1) at 385 nm respectively. The procedure has been applied to the analysis of cupronickel.

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Urea hydrolysis has been employed to raise the pH for homogeneous precipitation of zinc ammonium phosphate. From 30 to 100 mg of zinc can conveniently be determined by this technique (relative standard deviation 0.2% for 89 mg). The interference of nickel was minimized by using ammonium tartrate as masking agent, but copper could not be effectively masked with the same tartrate. Ammonium tartrate obtained from a different source was found to mask the copper more effectively. Investigations showed that the latter tartrate contained an appreciable amount of ammonium oxalate.

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Winkler's procedure for the determination of dissolved oxygen has been modified to cope with substantial amounts of oxidizing or reducing substances in the samples. The manganese(III) is treated with an excess of hydroquinone, the unconsumed part of which is then titrated with standard ceric sulphate solution. A blank determination is also carried out, in which the order of addition of reagents is reversed so that the solution is always acidic, to allow for the interfering substances present. Results obtained by using this modified procedure on clean samples are in good agreement with results obtained by the usual Winkler method.

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A method is described for the amperometric titration of nickel and successive amperometric determination of copper and nickel. Nickel (1.0-16.0 mg) and copper (1.0-11.0 mg) could be determined with an average error of less than 1%. Cobalt interferes but chloride does not. Interference by aluminium, iron(III) and chromium can be eliminated. Zinc and manganese do not interfere if the correct applied voltage is chosen. The procedures can be utilized in the analysis of alloys such as nichrome, Raney nickel, constantan, german silver and manganin. It is best to use the standard addition method for less than 3 mg of nickel.