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Background: Specialized freeze-drying process is being used in the field for different thermostable vaccine preparation worldwide. The thermostability remains only in undiluted conditions. If dilution is made at the morning and used for the whole day, the vaccine efficacy is compromised at high ambient temperature. In this study, trehalose based specialized vaccine diluent was used to improve the stability of Peste des petits ruminants (PPR) vaccine in diluted condition. Methods: The available PPR vaccine was reconstituted with conventional diluent and with trehalose based test diluent. The diluted vaccine was kept at ambient temperature without maintaining any cool chain. Stability of diluted vaccine virus was further assessed in vivo and in vitro at different temperatures. Goats were vaccinated and Vero cells were infected with reconstituted vaccines and were assessed at 0, 3, 6, 9 and 24 hours post dilution. Antibody titer was measured and virus infectivity titer was determined in both cultured cell lysate and supernatant. The presence of the virus particles in Vero cell was confirmed by standard RT-PCR targeting Fusion (F) gene of PPR virus. Results: In vivo results revealed that the number of goats possessed antibodies to PPR virus was higher in trehalose based vaccine formulation than the conventional PBS based diluent. Reconstituted vaccine virus (using PBS and trehalose diluent) infected Vero cells produced 70-80% cytopathic effect (CPE) in 5th days of post infection. Both diluents produced and maintained infectivity titer from log10 TCID50 5.5 to log10 TCID50 3.6, until the use of vaccines incubated for 9 hours after dilution. On the other hand, at 24 hours of post dilution only trehalose formulated vaccine produced log10 TCID50 2.5 whereas no infectivity titer was observed at the same time using conventional one. Conclusion: The present study suggests that trehalose preserves the quality of reconstituted vaccine in terms of infectivity titers. Trehalose can be a diluent of choice for reconstitution of PPR vaccine in field. [ABSTRACT FROM AUTHOR]

Dhaka Zoo with 2000 animal heads of 184 species from significant genetic diversity and five million visitors' influx round the year is placing it a public health important spot. This study was conducted to investigate histoplasmosis in animals at Dhaka Zoo to ascertain animal health, welfare and public health safety standard. One hundred and two necropsied tissue samples preserved in 10% neutral buffered formalin at necropsy from 36 animals of 25 different species were collected from Dhaka Zoo during 2007 - 2009. Twenty five out of 36 study animals were suffering from granulomatous diseases of mycotic and/or bacterial origin. Among them three animals were found suffering from histoplasmosis. Clinical history, nodular lesions from necropsy findings, granulomatous reactions with fungal spores on histopathology; macrophages laden with histoplasma organisms on histopathology and on special staining were revealed histoplasmosis in six rhesus macaques (Macaca mulatta). Present study provides evidence of existing histoplasmosis and similar long standing zoonotic diseases in majority of rest of the animals with health risk that shades health safety standard at Dhaka Zoo. [ABSTRACT FROM AUTHOR]

Dhaka Zoo with 2000 animal heads of 184 species from significant genetic diversity and five million visitors' influx round the year is placing it a public health important spot. This study was conducted to investigate blastomycosis in animals at Dhaka Zoo to ascertain animal health, welfare and public health safety standard. One hundred and two necropsied tissue samples preserved in 10% neutral buffered formalin at necropsy from 36 animals of 25 different species were collected from Dhaka Zoo. Twenty five out of 36 study animals were suffering from granulomatous diseases. Among them three animals were found suffering from blastomycosis. Clinical history, nodular lesions from necropsy findings, granulomatous reactions with fungal spores on histopathology and spherical yeast cells with double contoured wall and broad base budding on special staining were used for the confirmation of blastomycosis in spotted deer (Cervus axis/Axis axis), nilgai (Boselaphus tragocamelus) and horse (Equus caballus). Present study provides evidence of existing blastomyosis and similar long standing zoonotic diseases in majority of rest of the animals with health risk that shades health safety standard at Dhaka Zoo. [ABSTRACT FROM AUTHOR]