Objective:To characterize Pasteurella isolated from backyard chickens using whole cell protein lysate profiles and random amplified polymorphic DNA(RAPD)techniques to show their genetic relationship because Pasteurcll...Objective:To characterize Pasteurella isolated from backyard chickens using whole cell protein lysate profiles and random amplified polymorphic DNA(RAPD)techniques to show their genetic relationship because Pasteurclla multocida(P.multocida)is an important cause of fatal infections in backyard chickens.Methods:Twenty one P.multocida isolates were recovered previously from clinical cases of fowl cholera belonging to individual owners and phenotypically analysed using biochemical tests and serotyping were used far the genetic characterization.Results:Phylogenetic study based on both methods revealed that the recovered population of P.multocida isolated from backyard chickens differs markedly,constituting a well-separated cluster and appearance of 3 distinguishing lineages with greater discrimination shown by RAPDPCR that resulted in two suclusters in cluster A and three subclusters in cluster B and were related greatly with capsular serogroups for the examined strains.The whole cell protein revealed the presence of dominant protein bands at approximately 41 and 61 kDa in all of the examined isolates that may be a virulent proteins share in the increasing of its pathogenicity.Clear distinctive bands ranged from 123 to 1534 bp.Conclusions:Based on the previous findings,there are three spreading clusters that may indicate the association of a small number of P.multocida variants with the majority of cases suggesting that certain clones of P.multocida are able to colonue the examined backyard chickens.Also,the ease and rapidity of RAPD-PCR support the use of this technique as alternative to the more labour-intensive SDS-PACE system for strain differentiation and epidemiological studies of avian P.multocida.Further application of RAPD technology to the examination of avian cholera outbreaks in commercially available flocks may facilitate more effective management of this disease by providing the potential to investigate correlations of P.multocida genotypes,to identify affiliations between bird types and bacterial genotypes,and to elucidate the role of specific bird species in disease transmission.展开更多
In order to investigate the effects of all-trans retinoic acid (ATRA) against bacterial infection in chickens, 35 3-day-old AA broiler chickens were fed adaptively for two days and randomly divided into five groups,...In order to investigate the effects of all-trans retinoic acid (ATRA) against bacterial infection in chickens, 35 3-day-old AA broiler chickens were fed adaptively for two days and randomly divided into five groups, including Escherichia coli experimental group ( group 1 ), Escherichia coli control group (group 2), blank control group ( group 3 ), PasteureUa experimental group ( group 4), and PasteureUa control group ( group 5 ). At 5 days of age, the chickens in group 1 and group 4 were drenched with 5 p.mol/kg ATRA for seven consecutive days according to their weight; the chickens in group 2, group 3 and group 5 were drenched with an equal volume of dimethyl sulfoxlde (DMSO). The clinical symptoms and weight changes in each group were observed and recorded. Seven days later, the chickens were euthanized and dissected to determine the immune organ indexes. The results showed that there were significant differences in body weight between ATRA-administrated chickens and non-administrated chickens after bacterial infection (P 〈 0.05 ) ; moreover, the immune organ indexes of ATRA-administrated chickens exhibited significant differences compared with control group (P 〈 0.05 ), indicating that ATRA could promote the development of immune organs of poultry, thereby enhancing the body immunity against bacterial infection.展开更多
In order to study the anti-bacterial infection effect of polysaccharide from Agaricus blazei Murrill on chickens, the experimental groups were orally administrated A. blazei polysaccharide at low dose and high dose, r...In order to study the anti-bacterial infection effect of polysaccharide from Agaricus blazei Murrill on chickens, the experimental groups were orally administrated A. blazei polysaccharide at low dose and high dose, respectively, for 14 d continuously, and then, the chickens in various groups were infected with Escherichia coli or Pasteurella pneumotropica , so as to observe the clinical symptoms of chickens and record the change in body weight. Anatomy was performed 14 d later, and the organ indices were determined, so as to study the anti-bacterial infection effect of A. blazei polysaccharide on chickens. The results showed that after bacterial infection, the high-dose A. blazei polysaccharide group was significantly differed from other groups in changes of body weight and organ indices. It indicates that oral administration of high concentration of A. blazei polysaccharide could promote the development of poultry organs, thereby improving the immunity of organisms.展开更多
基金Supported by Regular goveromental annual fund every Fiscal year from Assiut university(Grant No.9/020/08595/0)
文摘Objective:To characterize Pasteurella isolated from backyard chickens using whole cell protein lysate profiles and random amplified polymorphic DNA(RAPD)techniques to show their genetic relationship because Pasteurclla multocida(P.multocida)is an important cause of fatal infections in backyard chickens.Methods:Twenty one P.multocida isolates were recovered previously from clinical cases of fowl cholera belonging to individual owners and phenotypically analysed using biochemical tests and serotyping were used far the genetic characterization.Results:Phylogenetic study based on both methods revealed that the recovered population of P.multocida isolated from backyard chickens differs markedly,constituting a well-separated cluster and appearance of 3 distinguishing lineages with greater discrimination shown by RAPDPCR that resulted in two suclusters in cluster A and three subclusters in cluster B and were related greatly with capsular serogroups for the examined strains.The whole cell protein revealed the presence of dominant protein bands at approximately 41 and 61 kDa in all of the examined isolates that may be a virulent proteins share in the increasing of its pathogenicity.Clear distinctive bands ranged from 123 to 1534 bp.Conclusions:Based on the previous findings,there are three spreading clusters that may indicate the association of a small number of P.multocida variants with the majority of cases suggesting that certain clones of P.multocida are able to colonue the examined backyard chickens.Also,the ease and rapidity of RAPD-PCR support the use of this technique as alternative to the more labour-intensive SDS-PACE system for strain differentiation and epidemiological studies of avian P.multocida.Further application of RAPD technology to the examination of avian cholera outbreaks in commercially available flocks may facilitate more effective management of this disease by providing the potential to investigate correlations of P.multocida genotypes,to identify affiliations between bird types and bacterial genotypes,and to elucidate the role of specific bird species in disease transmission.
基金Supported by Project of Educational Reform,Innovation,Guidance and Development for College Teachers in Tianjin Agricultural University(20171003)Student's Platform for Innovation and Entrepreneurship Training Program(201610061008,201710061045)
文摘In order to investigate the effects of all-trans retinoic acid (ATRA) against bacterial infection in chickens, 35 3-day-old AA broiler chickens were fed adaptively for two days and randomly divided into five groups, including Escherichia coli experimental group ( group 1 ), Escherichia coli control group (group 2), blank control group ( group 3 ), PasteureUa experimental group ( group 4), and PasteureUa control group ( group 5 ). At 5 days of age, the chickens in group 1 and group 4 were drenched with 5 p.mol/kg ATRA for seven consecutive days according to their weight; the chickens in group 2, group 3 and group 5 were drenched with an equal volume of dimethyl sulfoxlde (DMSO). The clinical symptoms and weight changes in each group were observed and recorded. Seven days later, the chickens were euthanized and dissected to determine the immune organ indexes. The results showed that there were significant differences in body weight between ATRA-administrated chickens and non-administrated chickens after bacterial infection (P 〈 0.05 ) ; moreover, the immune organ indexes of ATRA-administrated chickens exhibited significant differences compared with control group (P 〈 0.05 ), indicating that ATRA could promote the development of immune organs of poultry, thereby enhancing the body immunity against bacterial infection.
基金Supported by Tianjin Science and Technology Popularization Project(17KPHDSF00110)Education Reform,Innovation and Guidance Program for Teachers in Universities of TianJin Agricultural University(20171003)
文摘In order to study the anti-bacterial infection effect of polysaccharide from Agaricus blazei Murrill on chickens, the experimental groups were orally administrated A. blazei polysaccharide at low dose and high dose, respectively, for 14 d continuously, and then, the chickens in various groups were infected with Escherichia coli or Pasteurella pneumotropica , so as to observe the clinical symptoms of chickens and record the change in body weight. Anatomy was performed 14 d later, and the organ indices were determined, so as to study the anti-bacterial infection effect of A. blazei polysaccharide on chickens. The results showed that after bacterial infection, the high-dose A. blazei polysaccharide group was significantly differed from other groups in changes of body weight and organ indices. It indicates that oral administration of high concentration of A. blazei polysaccharide could promote the development of poultry organs, thereby improving the immunity of organisms.