Assessment of immune response in cattle against experimentally prepared trivalent (O, A, and Asia-1) FMD vaccine in Bangladesh

This research work was conducted to investigate the effects of age, sex and breed on the induction of immune response against experimentally prepared inactivated trivalent (type O, A, and Asia-1) FMD vaccine. Twenty six cattle were divided into four test groups (Group A, B, C, and D; 5 cattle in each group) and one control group (n=6) based on breed (local and cross), age (≤12 months and >12 months), and sex (male and female). Test cattle were vaccinated with the experimentally prepared trivalent FMD vaccine. Pre- and post vaccinated sera from the vaccinated cattle were collected upto 63 days, and the sera were tested using liquid phase blocking enzyme linked immunosorbent assay (LPBE) that was specific for FMD serotypes O, A, and Asia-1. Antibody titers of all the pre-vaccinated serum samples were found to be under protection level. The females were found to be more protected (90%; n=9/10) as compared to males (70%; n=7/10). The titers obtained were statistically analyzed using t–test to observe the effects of age, breed and sex. It was observed that the mean values of antibody titer in cattle aging >12 months against O, A, and Asia-1 serotypes were significant (P12 months showed better immune response towards trivalent FMD vaccine

Reverse transcription polymerase chain reaction (RT-PCR) based detection and serotyping of FMD Virus from field samples of Gazipur, Bangladesh, and adaptation of the virus in BHK-21 cell

The study aimed for the detection and serotyping of Foot and Mouth Disease virus (FMDV) circulating in Kapasia Upazila, Gazipur district of Bangladesh during 2013. Twelve samples comprising of tongue epithelium (n=8) and inter digital tissue (n=4) were collected from suspected cattle, and inocula were prepared. The inocula were inoculated into confluent BHK-21 cell line for virus propagation. After 3 subsequent passages; progressive cytopathic effects (CPE) specific for FMDV i.e., rounding and flattening of cells, breaking down of the intercellular bridge and finally cell death (almost 100%) were observed; these were indicative of successful virus propagation in the cells. Viral RNA was extracted, and Reverse Transcription Polymerase Chain Reaction (RT-PCR) was performed using three sets of primers corresponding to the serotype and lsquo;O', and lsquo;Asia-1' and and lsquo;A', respectively. Out of the 12 samples, 10 (83.33%) were found to be positive for FMDV, and all of those were of serotype and lsquo;O'. It is concluded that FMDV serotype and lsquo;O' is circulating among the cattle of Gazipur district, Bangladesh. [J Adv Vet Anim Res 2015; 2(3.000): 291-295

Isolation of Pasteurella multocida from chickens, preparation of formalin killed fowl cholera vaccine, and determination of efficacy in experimental chickens

Objectives: The objectives of this study were to isolate and identify Pasteurella multocida from fowl cholera (FC) suspected chicken, and to prepare and efficacy determination of formalin killed fowl cholera vaccine using the isolated P. multocida strain. Materials and methods: A total of five suspected dead chickens were collected from Brothers Poultry Farm located at Gazipur district, Bangladesh. The samples were processed and the P. multocida was isolated through conventional bacteriological techniques, were finally confirmed by polymerase chain reaction using P. multocida specific primers targeting cap gene. The P. multocida isolate was used to develop a formalin killed fowl cholera vaccine. The efficacy of the newly prepared vaccine was determined in Starcross-579 chickens (n=30) aging 15 weeks either by injecting 1 mL (group-A; n=10) or 0.5 mL (group-B; n=10) vaccine containing approximately 3.2x108 CFU/mL P. multocida organism; 10 birds were kept as unvaccinated control. The sera from the vaccinated and control birds were collected and were subjected for antibody titre determination by enzyme-linked immunosorbent assay (ELISA). Finally the vaccinated birds were challenged using virulent strains of P. multocida to confer the protection against FC. Results: P. multocida could be isolated from both the samples. The formalin killed vaccine prepared from the isolated bacteria was subjected for the determination of antibody titre in chicken, and found that the antibody titres in the birds of group A and group B were 4.513 and 4.07 respectively after primary vaccination, and 4.893 and 4.37 respectively after booster vaccination. Most of the vaccinated birds were found to be survived after challenging with virulent strain of P. multocida. Conclusion: It is concluded that the causal agent of FC (P. multocida) was successfully isolated from FC affected dead chickens. The prepared formalin killed fowl cholera vaccine induces protective immune response and conferred protection against challenge infection caused by the virulent strain of P. multocida. [J Adv Vet Anim Res 2016; 3(1.000): 45-50

Remedy of contamination of multidrug resistant Salmonella and Escherichia coli from betel leaves (Piper betle) keeping them fresh for long time

Objective: The present study was carried out to identify the associated Salmonella and Escherichia coli in betel leaves (Piper betle), and to develop an effective method to remove those microbes. Materials and methods: Betel leaves were collected from local and whole sale markets, and borouj (cultivation place). Salmonella and E. coli were isolated and identified by cultural, morphological, and biochemical tests followed by confirmation by polymerase chain reaction (PCR) targeting the genus specific 16S rRNA genes. Antibiogram of the isolated bacteria was performed by disc diffusion method. Different concentrations of Salmosan-A Soln were used to remediate the contaminating bacteria keeping the quality of betel leaves for longer periods. Results: Total Salmonella counts in the betel leaves were 3.9×105, 4.9×106, 3.5×104, 1.1×103 and 1.5×103 CFU/mL, while E. coli counts were 5.5×107, 6.3×107, 4.4×105, 3.3×103 and 3.1×103 CFU/mL in the betel leaves collected from K.R. market, Kewatkhali Bazaar, whole sale market, borouj in Kushtia and borouj in Natore, respectively. Antibiogram study revealed that the isolated bacteria were sensitive to doxycyclline, ciprofloxacin, chloramphenicol and cefotaxime. Application of 0.3% Salmosan-A Soln was found to be the most effective and suitable, where [J Adv Vet Anim Res 2018; 5(1.000): 73-80

Molecular characterization of Duck Plague virus isolated from Bangladesh

Duck plague (DP) is the most feared duck disease in the world. For isolation, identification, molecular detection and characterization of DP virus (DPV), a total of 94 samples were collected from commercial farms (n=6) and households (n=13) from Rajshahi (n=37), Netrokona (n=35) and Mymensingh (n=22) districts of Bangladesh. The samples were processed and inoculated into 11-13 days old embryonated duck eggs for virus propagation. Virus was identified using agar gel immunodiffusion test (AGIT) and passive hemagglutination (PHA) test, and was confirmed by polymerase chain reaction (PCR) targeting DNA polymerase and gC genes, followed by sequencing. Pathogenicity tests were performed using duck embryos, ducklings and ducks. Among the 94 samples, 17 isolates were confirmed as DPV by PCR amplification of partial DNA polymerase (446-bp) and gC genes (78-bp), respectively. One of the isolates (Anatid herpes 1 BAU DMH) was sequenced and found to be closely related with a Chinese variant of DPV (GenBank: JQ647509.1). Thus, we assume that both Bangladeshi and Chinese isolates of DPV may have a common ancestor. [J Adv Vet Anim Res 2015; 2(3.000): 296-303

Surveillance, epidemiological, and virological detection of highly pathogenic H5N1 avian influenza viruses in duck and poultry from Bangladesh

Avian influenza viruses (AIVs) continue to pose a global threat. Waterfowl are the main reservoir and are responsible for the spillover of AIVs to other hosts. This study was conducted as part of routine surveillance activities in Bangladesh and it reports on the serological and molecular detection of H5N1 AIV subtype. A total of 2169 cloacal and 2191 oropharyngeal swabs as well as 1725 sera samples were collected from live birds including duck and chicken in different locations in Bangladesh between the years of 2013 and 2014. Samples were tested using virus isolation, serological tests and molecular methods of RT-PCR. Influenza A viruses were detected using reverse transcription PCR targeting the virus matrix (M) gene in 41/4360 (0.94%) samples including both cloacal and oropharyngeal swab samples, 31 of which were subtyped as H5N1 using subtype-specific primers. Twenty-one live H5N1 virus isolates were recovered from those 31 samples. Screening of 1,868 blood samples collected from the same birds using H5-specific ELISA identified 545/1603 (34%) positive samples. Disconcertingly, an analysis of 221 serum samples collected from vaccinated layer chicken in four districts revealed that only 18 samples (8.1%) were seropositive for anti H5 antibodies, compared to unvaccinated birds (n=105), where 8 samples (7.6%) were seropositive. Our result indicates that the vaccination program as currently implemented should be reviewed and updated. In addition, surveillance programs are crucial for monitoring the efficacy of the current poultry vaccinations programs, and to monitor the circulating AIV strains and emergence of AIV subtypes in Bangladesh