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Prevalence of Toxoplasma gondii in retail fresh meat products from free-range chickens in Spain
2021
Salinas, María Jesús Gracia | Campos, Cristina Escolano | Peris, María Paz Peris | Kassab, Nabil Halaihel
Toxoplasma gondii is one of the most prevalent zoonotic protozoan parasites worldwide and affects the vast majority of warm-blooded animal species, including humans. Postnatal infection in humans occurs through the ingestion of sporulated T. gondii oocysts or via the oral intake of parasite tissue cysts during the consumption of raw or undercooked meat. In this regard, given their high exposure to oocysts, chickens (Gallus domesticus) raised on the ground constitute a potential source of T. gondii. For the first time in Spain, a survey was undertaken in commercial retail free-range poultry. A total of 50 thighs from different animals were analysed. The samples were homogenised and an acid pepsin digestion procedure was applied prior to molecular analysis. Toxoplasma gondii DNA was isolated from meat by qPCR. Two sets of primers were used for DNA amplification targeting the specific sequence of a 529 bp repeat element and another set of primers was utilised for the surface antigen protein-1 gene. DNA extracted from 5 out of 50 tissue samples was positive for both genes by qPCR amplification. The 10% prevalence of Toxoplasma infection found in commercial free-range chickens raises public health issues.
Show more [+] Less [-]Comparison of chicken immune responses after inoculation with H5 avian influenza virus-like particles produced by insect cells or pupae
2021
Huang, Dean | Chao, Yu-Chan | Lv, Zhengbing | Jan, Jia-Tsrong | Yang, Yuzhi | Hsiao, Pei-Wen | Wu, Jiaying | Liao, Chiu-Hsun | Wu, Tzu-Hsien | Wang, Lih-Chiann
Novel clade 2.3.4.4 H5 highly pathogenic avian influenza virus (HPAIV) outbreaks have occurred since early 2015 in Taiwan and impacted the island economically, like they have many countries. This research investigates the immunogenicity of two HPAIV-like particles to assess their promise as vaccine candidates. The haemagglutinin (HA) gene derived from clade 2.3.4.4 H5 HPAIV and matrix protein 1 (M1) gene were cloned into the pFastBac Dual baculovirus vector. The resulting recombinant viruses were expressed in Spodoptera frugiperda moth (Sf)21 cells and silkworm pupae to generate Sf21 virus-like particles (VLP) and silkworm pupa VLP. Two-week-old specific pathogen–free chickens were immunised and their humoral and cellular immune responses were analysed. The silkworm pupa VLP had higher haemagglutination competence. Both VLP types elicited haemagglutination inhibition antibodies, anti-HA antibodies, splenic interferon gamma (IFN-γ) and interleukin 4 (IL-4) mRNA expression, and CD4⁺/CD8⁺ ratio elevation. However, chickens receiving silkworm pupa VLP exhibited a significantly higher anti-HA antibody titre in ELISA after vaccination. Although Sf21 VLP recipients expressed more IFN-γ and IL-4, the increase in IFN-γ did not significantly raise the CD4⁺/CD8⁺ ratio and the increase in IL-4 did not promote anti-HA antibodies. Both VLP systems possess desirable immunogenicity in vivo. However, in respect of immunogenic efficacy and the production cost, pupa VLP may be the superior vaccine candidate against clade 2.3.4.4 H5 HPAIV infection.
Show more [+] Less [-]Antimicrobial resistance and recovery of Salmonella, Campylobacter, and Escherichia coli from chicken egg layer flocks in Canadian sentinel surveillance sites using 2 types of sample matrices
2021
Agunos, Agnes | Gow, Sheryl P. | Leger, David F. | Flockhart, Logan | Daignault, Danielle | Desruisseau, Andrea | Zabek, Erin | Pollari, Frank | Reid-Smith, Richard J.
Eggs are important to the diet of Canadians. This product is one of the supply-managed commodities in Canada, but unlike other commodities, where food safety risks are extensively explored and reported, information on the prevalence of enteric organisms (e.g., Salmonella, Campylobacter) and antimicrobial resistance (AMR) in layers in Canada are limited. This study was conducted to determine the prevalence of select bacteria and the associated AMR patterns in layer flocks using 2 sample matrices. Farms were located within FoodNet Canada and the Canadian Integrated Program for Antimicrobial Resistance Surveillance sentinel sites (SS). Fecal samples (Ontario: ONSS1a, ONSS1b) and environmental sponge swabs (British Columbia: BC(SS2a)) were collected. Salmonella prevalence was 29% and 8% in ONSS1a and ONSS1b, respectively, and 7% in BC(SS2a). S. Kentucky and S. Livingstone were the most frequently isolated serovars and no S. Enteritidis was detected. Campylobacter was not detected in the BC sponge swabs but was isolated from 89% and 53% of Ontario fecal samples (ON(SS1a) and ON(SS1b), respectively). Seven C. jejuni from Ontario were ciprofloxacin-resistant. Escherichia coli prevalence was high in both sample types (98%). Overall, tetracycline resistance among E. coli ranged from 26% to 69%. Resistance to ceftiofur (n = 2 isolates) and gentamicin (n = 2) was relatively low. There were diverse resistance patterns (excludes susceptible isolates) observed among E. coli in Ontario (10 patterns) and British Columbia (14 patterns). This study revealed that fecal samples are more informative for farm-level monitoring of pathogen and AMR prevalence. Without further validation, sponge swabs are limited in their utility for Campylobacter detection and thus, for public health surveillance.
Show more [+] Less [-]Detection of extended-spectrum β-lactamase (ESBL) producing Escherichia coli in chickens
2021
Rahman, Wahidur | Hossai̇n, Md. | Ali̇, Md. | Sultana, Tania | Hossain, K. M. Mozaffor
Indiscriminate use of antibiotics in poultry farms increases the chance of antibiotic resistant and extended-spectrum β-lactamase (ESBL) producing bacteria in Bangladesh. Therefore, the study was under taken to detect ESBL producing Escherichia coli (E. coli) in chickens. Materials and methods: A total of 60 cloacal swab samples (20 from commercial layer, 20 from commercial broiler and 20 from commercial sonali chickens) were collected from Rajshahi district of Bangladesh. The E. coli was isolated from these samples and identified based on cultural, staining, and biochemical characteristics. The disk diffusion method was used to assay the antibiotic resistant/sensitivity patterns of the isolated E. coli. Phenotypc detection of ESBL producing E. coli was also done.The prevalence of E. coli in chickens was 61.67% in Rajshahi district of Bangladesh, where the prevalence was 60%, 60%, and 65% in commercial layer, commercial broiler, and commercial sonali chickens, respectively. The antibiotic sensitivity assay of E. coli isolated from commercial layer chickens showed 100%, 80%, 50%, 40%, and 40% resistant to amoxicillin, tetracycline, cefotaxime, ciprofloxacin, and ceftazidime, respectively. E. coli isolated from commercial broiler chickens showed 100%, 100%, 60%, 50%, and 40% resistant to amoxicillin, tetracycline, cefotaxime, ceftazidime, and ciprofloxacin, respectively. E. coli isolated from commercial sonali chickens showed 90%, 70%, 50%, 50%, and 40% resistant to amoxicillin, tetracycline, cefotaxime, ciprofloxacin, and ceftazidime, respectively. In phenotypic detection, the overall prevalence of ESBL producing E. coli was 43.33%, where 40%, 50%, and 40% in the commercial layer, commercial broiler, and commercial sonali chickens, respectively in Rajshahi district of Bangladesh.These results indicated that chickens are a potential reservoir for ESBL producing E. coli and their antibiotic resistances are obviously significant. These findings will help us to make proper guideline for the treatment, prevention and control of E. coli prevalent in chickens in Bangladesh.
Show more [+] Less [-]Molecular characterization of fowl adenoviruses isolated from chickens in Malaysia
2021
Faizul Fikri M. Y. | Syamsiah Aini S. | Ong, G. H. | Maizatul Z. | Muhammad Redzuan S. | Mohammad Jiha R. | Leow, B. L.
Recently, Fowl Adenovirus (FAdV) cases have been reported in many countries worldwide. FAdV is a contagious agent associated with inclusion body hepatitis (IBH) and hydropericardium syndrome (HPS) in chickens. It belongs to the Aviadenovirus genus of the family Adenoviridae. The virus is classified into five species (A to E) and further divided into 12 serotypes. Depending on the serotypes, they have diverse characteristics of virus that can either be pathogenic or nonpathogenic strain. From the viewpoint of epidemiological as well as vaccine development, it is very important to detect FAdV strains. Previous studies have been conducted on molecular research, but the continuity of this study in Malaysia has been limited. This study aims to identify the serotype classification of five Malaysian FAdV isolates obtained from field outbreaks during 2017-2019. In this study, polymerase chain reactions (PCR) were conducted based on Hexon gene. Results from the nucleotide sequence analysis discovered that the five isolates showed high similarity with FAdV-8b strains. High bootstrap values in phylogenetic analysis supported the clustering of the Malaysian FAdVs isolates into FAdVs species E. Consequently, the result of this study contributed important information on the epidemiology and culminated in the importance of control strategies against FAdV infection in Malaysia.
Show more [+] Less [-]Molecular phylogenetics of Newcastle disease virus isolated from chickens in 2019
2021
Faizul Fikri M. Y. | Leow, B. L. | Muhammad Redzwa, S. | Faizah Hanim M. S. | Syamsiah Aini S.
Newcastle disease (ND) is an economically important, contagious poultry viral disease reported across the globe. No recent reports on ND circulating in Malaysia. Therefore, the aim of the study is to characterize 16 Newcastle disease viruses (NDVs) isolated from chickens in Malaysia in the year of 2019. All isolates were genotypically analyzed using reverse transcription-polymerase chain reaction (RT-PCR) with primers specific to the viral fusion (F) protein gene. Analysis of the F protein cleavage site’s deduced amino acid sequences revealed that from the Newcastle disease virus (NDV) isolates, three of them were virulent with two different motifs of 112RRQKRF117 and 12RRRKRF117 while other isolates were avirulent. Phylogenetic analysis demonstrated that three isolates were grouped in genotype VII, five in genotype I while eight in genotype II. All genotype VII isolates were clustered under sub-genotype VII.2 (VIIh and VIIi) which is the same strain causing previous outbreaks in Malaysia. Therefore, findings in this study demonstrated that there is no new introduction of NDV genotypes in Malaysia. However, farms should implement biosecurity measures at strict level as well as executing continuous monitoring and surveillance of the disease as these implementations would help them to conduct proper preventive measures and control of panzootic viruses in future.
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