DSpace Collection:
http://dspace.cvasu.ac.bd/jspui/handle/123456789/79
2024-03-29T07:42:26ZAN INVESTIGATION ON PERSISTENCY OF SALMONELLA PARATYPHI B VARIANT JAVA IN EXPERIMENTALLY INFECTED BACKYARD CHICKEN
http://dspace.cvasu.ac.bd/jspui/handle/123456789/2067
Title: AN INVESTIGATION ON PERSISTENCY OF SALMONELLA PARATYPHI B VARIANT JAVA IN EXPERIMENTALLY INFECTED BACKYARD CHICKEN
Authors: Yeasmin Tania, Sabiha
Abstract: Salmonella is by far the most widely distributed food-borne zoonotic pathogen. There are >2500 serovars of Salmonella enterica. All motile serovars are zoonotic, and poultry harbors a good number of them including Salmonella Paratyphi B variant Java (S. Java). Recently, isolates belonging to this serovar have been isolated from human non-typhoidal clinical cases of gastroenteritis in Bangladesh. Their source of origin in Bangladesh was unknown, but poultry could be a putative source, because reports in literature indicate that poultry could be its reservoir. But information on its persistency in infected/colonized backyard chickens is absent and this information is important to know because rural people in Bangladesh are closely associated with backyard chickens. Most motile serovars are generally colonized in poultry without causing any clinical disease, but can be shed from them to the environment causing a public health hazard. To explore the persistency of S. Java of human non-typhoidal case origin in backyard chickens and its potential to cause clinical disease 27 backyard chickens were infected orally at the rate of 1 ml per bird containingn106 CFU (Colony Forming Unit) and observed for 30 days post infection (DPI). The shedding of S. Java in faeces was screened using novobiocin-added Modified Semisolid Rappaport Vassiliadis (MSRV) medium and Brilliant Green Agar (BGA) by seeing spreading turbid growth on MSRV and bright red colonies on BGA. Persistency of the organism in different internal organs was investigated by taking inoculums of them from four sacrificed birds, and all dead birds.
Fecal samples from the infected chickens were collected by sterile swabs and then immediately immersed into test tubes containing peptone water and incubated for 24 hours at 37ºC. Following incubation, the broth cultures were inoculated onto MSRVP medium which was further incubated for 24 hours at 42ºC. Irrespective of shedding nature – continuous or intermittent, the last day at which fecal sample from a bird was diagnosed positive with S. Java, was considered its total period of shedding. S. Java shedding probability from the infected chickens was 67% (95%CI 44-82%) on DPI 2, 38% (95% CI 19-56%) on DPI 7, 17% (95% CI 5-34%) on DPI 16 and 4% (95% CI is 0.3-18%) on DPI 30. The survival probability of chickens was 82% (95% CI 61-92%) on DPI2; 63% (95% CI 42-78%) on DPI 8, 52% (95% CI 32-69%) on DPI 11 and 48% (95% CI 29-65%) on DPI 30. Of the infected chickens, 6 developed granulomatous lesions into lungs.2013-06-01T00:00:00ZStudy of prevalence of Gallibacterium in chickens in Bangladesh
http://dspace.cvasu.ac.bd/jspui/handle/123456789/2066
Title: Study of prevalence of Gallibacterium in chickens in Bangladesh
Authors: Dewan, Khadiza Begum
Abstract: The aim of the present study was to determine the prevalence of Gallibacterium spp. in chickens in Bangladesh through a cross-sectional study. A six months long study was conducted from July 2012 to December 2012 in the Chittagong and Gazipur districts. A questionnaire was used to record additional information, such as age of bird, kind of farm, sex, pathological lesion present, sample collection site etc. In total, 127 dead and live chickens were sampled of which 62 were broiler and 65 were layer birds. From these 127 chickens 156 swab samples were collected. All the swab samples were streaked onto blood agar base supplemented with 5% citrated bovine blood. After overnight incubation, if any colonies were found with about 1-2 mm in diameter plus a clear β-haemolytic zone, they were primarily considered as Gallibacterium. Such colonies were further tested with catalase and oxidase tests and those gave positive results were identified as Gallibacterium. They were subsequently preserved and finally tested with PCR using DNA from boiled isolates and previously published primer set to detect a 16S rRNA gene specific for Gallibacterium. The results disclose that the prevalence of Gallibacterium in chickens was about 20% and its prevalence in layer and broiler chickens were 12.9% and 26.2%, respectively (P>0.05). The isolation rate of Gallibacterium was higher from trachea compared with any other organs/sites. PCR test with the use of primers: 1133fgal (5’–TAT TCT TTG TTA CCA RCGG–3’) (Forward primer) and 114r (5’–GGT TTC CCC ATT CGG–3’) (reverse primer) might have poor sensitivity, if DNA is used from boiling of the isolates.2013-06-01T00:00:00ZPREVALENCE OF MYCOPLASMA SYNOVIAE IN THE POULTRY BREEDER FARMS AT CHITTAGONG
http://dspace.cvasu.ac.bd/jspui/handle/123456789/2065
Title: PREVALENCE OF MYCOPLASMA SYNOVIAE IN THE POULTRY BREEDER FARMS AT CHITTAGONG
Authors: Abid, Md. Harisul
Abstract: Throughout the world Mycoplasma synoviae (MS) is an important pathogen of poultry especially for chicken and turkey. It causes respiratory tract infection and infectious sinusitis. The study was conducted to determine the seroprevalence of Mycoplasma synoviae (MS) infection with associated risk factors and identification of MS organism in unvaccinated flocks of commercial breeder farms of Chittagong district from January 2012 to December 2012. The risk factors were selected as farm, flock size, age and season. Blood samples were aseptically collected from the wing vein using (3-ml) sterile disposable syringes. A total of 365 serum samples were collected and tested for MS using serum plate agglutination (SPA) test for determination of Mycoplasma synoviae seroprevalence. On the other hand tracheal swabs were collected from each sero-positive flocks for Polymerase Chain Reaction (PCR) to determine the presence of Mycoplasma synoviae (MS) organism. For statistical analysis (Chi square test and Pearson correlation) was used. Among the farms the highest prevalence was found to be 69.23% and the lowest was 28.57% with the average 60%. The seroprevalence of MS infection in the breeder farms was highest 70.53% with the flock size >10000 birds whereas it was lowest 53.79% in the flocks ranging from 4000- 7000. According to age group the prevalence was found highest 69% in >60 weeks age group of birds and lowest 42.25% in 10-19 weeks group. The seroprevalence of MS in winter season was found as highest as 64.37% whereas it was found lowest 57.52% in summer season. There was significant difference (p<0.05) among the seroprevalence of MS in different breeder farms, flock size and age groups but there was statistically no significant (p>0.05) difference in seroprevalence of MS among the winter, summer and rainy season. The results showed that occurrence of MS have a significant relationship with the age, flock size and farm condition. To confirm the presence of MS in the samples PCR test was applied using specific published primers to amplify a 214 bp region of the 16S rRNA gene of the organism. The DNAs of MS were extracted using boiling method. In PCR all sero–positive flocks showed positive result for MS. As it was possible to identify MS using PCR from samples taken directly from tracheal swabs avoiding time consuming and laborious conventional culture method, it may be suggested that the PCR method could be used as an alternate of culturing method for identification of the organism.2014-06-01T00:00:00ZA Study on experimental infection of Salmonella enterica serotype Kentucky in Backyard Chicken
http://dspace.cvasu.ac.bd/jspui/handle/123456789/2058
Title: A Study on experimental infection of Salmonella enterica serotype Kentucky in Backyard Chicken
Authors: Najmin, Shamima
Abstract: Salmonella is a widely-reported zoonotic bacterial pathogen and poultry is one its major reservoir and source to infect humans. There are >2500 serovars of Salmonella and all motile serovars are zoonotic. S. Kentucky is of one of the motile serovars which has recently been identified from poultry and humans in Bangladesh and the human isolates from non-typhoidal clinical cases were genetically closely related to those from poultry. However, its pathogenic potentials and shedding probability and duration from infected/colonized chickens have never been reported. To assess its pathogenic potentials and shedding probability 22 backyard chickens were infected orally, each with 106cfu, which were then observed for 23 days to see clinical signs, gross and histo-pathological changes, survivability, shedding of the organism in faeces and evidence of colonization in different internal organs, by organism isolation and identification. Novobiocin added Modified Semisolid Rappaport Vasiliadis (MSRV) and Brilliant Green Agar (BGA) were used for the organism isolation and identification following standard procedures. Polymerase chain reaction (PCR) using universal primers for Salmonella was also applied on some representative samples to identify the presence of Salmonella. Four chickens, 2 on day 2 post infection (DPI 2) and the other 2 on DPI 15 were sacrificed and the internal organs were examined bacteriologically and histo-pathologically using standard procedures. The results showed that the zoonotic S. Kentucky strain of human non-typhoidal clinical case origin could cause reduced feed intake, watery or pasty fecal droppings, catarrhal enteritis and typhlitis in backyard chickens. No noticeable histopathological changes were seen in any internal organs after DPI 2, but spleen had reactive changes in prolonged course of infection. The probability of S. Kentucky shedding was 77% (95% CI 54-90%) on DPI 2, 41% (95% CI 21-60%) on DPI 12 and 13% (95% CI 3-31%) on DPI 21. The survival probability of the infected chickens was 50% (95% CI 28-68%) on DPI 6, 32% (95% CI 14-51%) on DPI 15 and 14% (95% CI 3-31%) on DPI 23.2013-06-01T00:00:00Z