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Molecular detection of Haemoproteus in homing pigeons (Colombia livia domestica) in Mazandaran Province
2017
Tabaripour, Seyed Reza | Youssefi, Mohammad reza | Rahbari, Sadegh | Arghavan, Mohammad
Background: Haemoproteus is a parasitic protozoa that over 120 species of it has been reported from wild aquatic birds, sparrows and other birds orders. So far, no study has been performed to determine the species of this protozoa in the north of Iran.Objectives: The aim of this study was to investigate the molecular and structural properties of Heamoproteus protozoa in the blood of infected pigeons in Mazandaran province.Methods: In the present study molecular investigation of Haemoproteus infection was carried out in domestic pigeons of Mazandaran province. For this purpose, samples obtained randomly from 150 pigeons in different regions of Mazandaran. At first, blood samples were stained with Gimsa stain and examined for presence of Haemoproteus gametocytes. Then, positive samples were used for PCR by Cytochrome b genes.. Results: Obtained results after morphological survey showed that 17 samples were positive indicating infection rate of 11.33%. Molecular investigation and analysis of PCR products showed that all of the samples belonged to Haemoproteus columbae species.Conclusion: So, being precisely familiar with this kind of protozoan and its species can limit many mistakes and be helpful in differential diagnosis of different species. This study has revealed that the most common species of Haemoproteus in Mazanadran province is Haemoproteus columbae.
显示更多 [+] 显示较少 [-]Mixed infection of peste-des-petits ruminants and Capripox in goats in south Kivu, Democratic Republic of Congo
2017
Birindwa, B.A. | Gitao, C.G. | Bisimwa, P.N. | Okafor, C. | Bebora, C.L.
Objective: We aimed at determining the prevalence and characterizing the CaPV, determining the CaPV-PPRV coinfection prevalence and providing data about phylogenetic relationship between the fusion protein of PPRV and P32 gene of CaPV. Materials and methods: A total of 150 samples including animals swabs, tissues and blood were collected from unvaccinated goats in a PPR and/or Capripox outbreaks in South Kivu, Eastern of Democratic Republic of the Congo. Conventional PCR and reverse transcriptase (RT-PCR) were used respectively to amplify P32, RPO30, GPCR genes of Capripox virus and Fusion (F) protein of PPRV. Positive samples were sequenced for phylogenetic analysis. Results: Out of 150 tested animals, 64.7% (n=97/150) were PPRV positive, 52.7% (n=79/150) were Capripox positive and 38.7% (n=58/150) were positive for both PPRV and CaPV. The pairwise comparison of P32gene of CaPV and F gene of PPRV showed 99.75% of identity percentage among goatpox virus sequences, 96.95% among PPRV sequences and 47.91% between CaPV and PPRV sequences. Conclusion: The study has demonstrated high prevalence of CaP V-PPRV mixed infection in South Kivu. Lumpy skinvirus disease (LSVD) is a lineage circulating which has a genetic relationship between its P32gene and the Fgene of PPRV giving the challenge to differentiate the two diseases at the clinical farm level.
显示更多 [+] 显示较少 [-]Genetic and pathogenic characterisation of a virulent Akabane virus isolated from goats in Yunnan, China
2022
Gao, Hua-Feng | Wang, Jin-Ping | Yang, Zhen-Xing | Xie, Jia-Rui | He, Yu-Wen | Hong, Qiong-Hua | Xin, Ai-Guo
Akabane virus (AKAV) has been detected in a variety of host species in China, but there are only limited records of its occurrence in goats. However, more attention needs to be paid to understanding the diversity of viruses in this species. The aim of the study was to explore the genotype characteristics and variation trend of AKAV and their relationship with virulence in Yunnan, China. Blood samples were collected from goats during routine surveillance of goat diseases in Yunnan province in 2019. The AKAV CX-01 strain was isolated using BHK-21 cells. To understand pathogenicity, the virus was intraperitoneally (IP) and intracerebrally (IC) inoculated into suckling mice and tissue samples were subsequently analysed histopathologically and immunohistochemically. Akabane virus CX-01 strain induced encephalitis and impairment of the central nervous system with fatal consequences. Phylogenetic analysis based on the ORF sequences of the small segments indicated that the AKAV isolate used was most closely related to the GD18134/2018 Chinese midge and bovine NM BS/1strains, while phylogenetic analysis based on the medium segments showed a close relationship between CX-01 and the Chinese GLXCH01 strain. The CX-01 isolate was related to AKAV genogroup Ia and probably originated from a recombination of different strains.
显示更多 [+] 显示较少 [-]Molecular characterisation of the Mycobacterium bovis causing bovine tuberculosis outbreaks in Poland
2020
Krajewska-Wędzina, Monika | Kozińska, Monika | Radulski, Łukasz | Lipiec, Marek | Augustynowicz-Kopeć, Ewa | Weiner, Marcin | Szulowski, Krzysztof
Since 2009, Poland has been recognised as a country officially free of bovine tuberculosis (bTB), although in each year of the last five there were from 8 to 18 outbreaks of the disease. In 2008–2016, the largest number of cattle infected with bovine mycobacteria were eliminated in the Masovian Province (the central region of Poland) and the largest number of outbreaks of this zoonosis were recorded in this area. The close proximity of farms where bTB was found led to the suspicion that tuberculosis could have been transmitted between the affected herds. The aim of the study was the molecular characterisation of the pertinent M. bovis/caprae strains and determination of the epidemiological relationship of various bTB outbreaks. The material for microbiological tests came from 119 cattle (Bos taurus) from nine herds located in five provinces, neighbouring the Masovian Province. Laboratory tests of tissue material gave results confirming tuberculosis in 54 (45%) animals. All strains belonged to the Mycobacterium bovis species. A two-step analysis of genetic affinity allowed 50 strains to be identified as phylogenetically closely related and separated between three genetic clusters consisting of 2 to 27 strains. Based on the results of genotyping, bTB outbreaks were found in three herds, and three transmission chains were identified among these herds.
显示更多 [+] 显示较少 [-]Molecular study of Cysticercus tenuicollis from slaughtered sheep in Sulaymaniyah province, Iraq
2020
Mohammed Aram Ahmad
Cysticercosis caused by the larval stage of Taenia hydatigena is economically the most important endemic parasitic disease in Iraq. Few data are available relating to the genetic divergence of this helminth. This study aimed to molecularly characterise Cysticercus tenuicollis isolates from sheep in Sulaymaniyah province, Iraq.
显示更多 [+] 显示较少 [-]Virulence factors and antibiotic resistance of avian pathogenic Escherichia coli in eastern China
2019
Xu, Xiaojing | Sun, Qing | Zhao, Lixiang
Avian pathogenicEscherichia coli (APEC) causes serious colibacillosis and significant economic losses. Data on profiles of virulence factors and antibiotic resistances among APEC strains are crucial to the control of infection. In this study, strains were isolated from eastern China, and the prevalence of virulence factors and distribution of antibiotic resistance were determined. APEC strains were isolated and characterised by PCR for O serogroups, virulence factor genes, antibiotic resistance, and phylogenetic groups. O78 was the most prevalent serogroup and type A was the most frequent phylogenetic group. ThefimH,feoB, andiron genes were the most prevalent among the isolates. All isolates were multiresistant, and all strains were resistant to ampicillin and tetracycline, which are widely used in the poultry industry in China. This study provided important data on the presence of virulence genes and antibiotic resistance profiles of APEC from poultry farms in eastern China.
显示更多 [+] 显示较少 [-]Prevalence and phylogenetic analysis of Mycoplasma synoviae strains isolated from Polish chicken layer flocks
2019
Kursa, Olimpia | Tomczyk, Grzegorz | Sawicka, Anna
Introduction: Mycoplasma synoviae (MS) is a chicken pathogen of major economic importance. Material and Methods: Between 2010 and 2016, 906 commercial layer chicken flocks in Poland were examined for MS, and the phylogenetic relationship among the strains was established. Regionally dispersed samples were collected and tested with the use of real-time PCR to detect the 16S–23S intergenic spacer region. Positive samples were also tested with LAMP and conventional PCR to detect the vlhA gene. Results: MS genetic material was detected in 265 (29%) of the tested flocks by real-time PCR, in 227 by the LAMP method and in 202 (22%) by conventional PCR. The by-year percentage of positive samples began at 34% in 2010, rose to 44% in 2012, and declined to 29% in 2016. A phylogenetic analysis of Polish M. synoviae strains using a partial sequence of the vlhA gene showed nine genotypes (A–I), the most frequently occurring being F and C. Pathogenic Polish MS field isolates (n = 27) collected from chickens with clinical signs of infection were grouped for their characteristic symptoms: respiratory for genotypes C, E, F, and I (n = 13), EAA and a drop in laying for genotypes F, E, and C (n = 12), and synovitis for genotype A (n = 2). Conclusion: These data showed the country’s isolate diversity. The high prevalence suggests the need to introduce appropriate control programmes. This is the first report of molecular epidemiological data on M. synoviae infection in layer chickens in Poland.
显示更多 [+] 显示较少 [-]Characterisation of newly emerged isolates of classical swine fever virus in China, 2014–2015
2017
Leng, Chaoliang | Zhang, Hongliang | Kan, Yunchao | Yao, Lunguang | Li, Mingliang | Zhai, Hongyue | Li, Zhen | Liu, Chunxiao | Shi, Hongfei | Ji, Jun | Qiu, Reng | Tian, Zhijun
Introduction: In 2014–2015, the epidemic of classical swine fever (CSF) occurred in many large-scale pig farms in different provinces of China, and a subgenotype 2.1d of CSF virus (CSFV) was newly identified. Material and Methods: The phylogenetic relationship, genetic diversity, and epidemic status of the 2014–2015 CSFV isolates, 18 new CSFV isolates collected in 2015, and 43 other strains isolated in 2014–2015 were fully analysed, together with 163 CSFV reference isolates. Results: Fifty-two 2014–2015 isolates belonged to subgenotype 2.1d and nine other isolates belonged to subgenotype 2.1b. The two subgenotype isolates showed unique molecular characteristics. Furthermore, the 2.1d isolates were found to possibly diverge from 2.1b isolates. Conclusion: This study suggests that the Chinese CSFVs will remain pandemic.
显示更多 [+] 显示较少 [-]Occurrence of Ornithobacterium rhinotracheale in Polish turkey flocks
2022
Kursa, Olimpia | Tomczyk, Grzegorz | Sawicka-Durkalec, Anna
Ornithobacterium rhinotracheale (ORT) causes significant economic losses to the poultry industry around the world. The bacterium often affects poultry as part of multiple infections causing very serious clinical signs that are usually not limited only to the respiratory system. This study’s main objective was the retrospective detection and identification of ORT in turkey flocks. ORT identification was performed in 6,225 samples taken from 133 different flocks between 2015 and 2020. Molecular methods were used, specifically real-time PCR and traditional PCR. We focused on partial 16S rRNA gene sequences of isolates, which were compared with sequences obtained from GenBank. The reaction products were analysed phylogenetically. Molecular methods indicating secondary infections was carried out, and the bacterial composition of the upper respiratory tract was 16S metasequenced for selected flocks to identify any other pathogens. The presence of ORT was detected in 30.83% of samples by real-time PCR and 28.57% by PCR. Phylogenetic analysis of the PCR products from the turkeys samples showed that their sequences resolved into two main genetic groups. Tests for the occurrence of secondary infections showed the presence of Mycoplasma gallisepticum and M. synoviae in some samples but the total absence of Bordetella avium. The upper respiratory tract in turkeys was dominated by two major phyla Firmicutes and Proteobacteria. At the genus level, the genera Ornithobacterium, Mycoplasma, Gallibacterium, Avibacterium, and Escherichia-Shigella were found which may include pathogenic bacteria that can cause clinical symptoms. The results of the analysis of multiple infection carried out in flocks with respiratory signs are probably associated with outbreaks of ornithobacteriosis in turkey flocks in Poland.
显示更多 [+] 显示较少 [-]Molecular characteristics and genetic diversity of Fasciola hepatica from sheep in Xinjiang, China
2022
Xifeng, Wang | Kai, Zhang | Guowu, Zhang | Zhiyuan, Li | Yunxia, Shang | Chengcheng, Ning | Chunhui, Ji | Jun, Qiao | Qingling, Meng | Xuepeng, Cai
Fasciola hepatica is a trematode infecting ruminants worldwide and occasionally affecting other animal species, including humans. It causes significant economic losses. Geographic distribution and patterns of infection must be considered before control and management measures are developed for this parasite. DNA molecular markers are useful for the identification of flukes and elucidation of their genetic evolution. Therefore, the population structure of F. hepatica was studied using this method in sheep in Xinjiang, China. The molecular characteristics, genetic relationships within the population and dispersal patterns of F. hepatica isolates were analysed based on the cox1 and nad1 genes. The population structure of F. hepatica from three regions of Xinjiang was explored and a neutrality test was conducted. The cox1 and nad1 genes have 21 and 42 variable sites, respectively, which can be classified into 34 and 33 haplotypes. Median-joining network and phylogenetic tree analyses showed that there was no significant variation in F. hepatica isolates between the three geographical regions. Analysis of variance revealed that the genetic variation of F. hepatica was mainly present within the populations. The neutrality test indicated that the populations were relatively stable but the Hami population may have undergone short-term expansion. This study revealed for the first time the molecular characteristics, genetic diversity and dispersal patterns of F. hepatica isolates from sheep in Xinjiang, thus providing new insights into the genetic variation and haplotype diversity of F. hepatica from indigenous sheep.
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