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1.
Vet Microbiol ; 239: 108446, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31767080

RESUMO

Plasmid-mediated extended-spectrum ß-lactamase and AmpC ß-lactamase (ESBL/pAmpC) producing bacteria are present at all levels of the broiler production pyramid. Young birds can be found positive for ESBL/pAmpC-producing Escherichia coli shortly after arrival at farm. The aim of this study was to determine the effect of different challenge doses of ESBL/pAmpC-producing E. coli on time-until-colonization and the level of excretion in young broilers. One-day-old broilers (specific-pathogen free (SPF) and conventional Ross 308) were housed in isolators and challenged with 0.5 ml ESBL/pAmpC-producing E. coli strains of varying doses (101-105 CFU/ml). Presence and concentration (CFU/gram feces) of ESBL/pAmpC-producing E. coli and total E. coli were determined longitudinally from cloacal swabs, and in cecal content 72 h after challenge. Higher challenge doses resulted in shorter time-until-colonization. However, even the lowest dose (101 CFU/ml) resulted in colonization of the broilers which excreted >106 CFU/gram feces 72 h after inoculation. Conventional broilers were colonized later than SPF broilers, although within 72 h after challenge all broilers were excreting ESBL/pAmpC-producing E. coli. A probabilistic model was used to estimate the probability of colonization by initial inoculation or transmission. The higher the dose the higher the probability of excreting ESBL/pAmpC-producing E. coli as a result of inoculation. In conclusion, low initial doses of ESBL/pAmpC-producing E. coli can result in rapid colonization of a flock. Interventions should thus be aimed to eliminate ESBL/pAmpC-producing bacteria in the environment of the hatchlings and measures focusing at reducing colonization and transmission of ESBL/pAmpC-producing E. coli should be applied shortly after hatching.


Assuntos
Infecções por Escherichia coli/veterinária , Doenças das Aves Domésticas/microbiologia , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Galinhas , Escherichia coli/enzimologia , Escherichia coli/genética , Infecções por Escherichia coli/enzimologia , Infecções por Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Plasmídeos/genética , Doenças das Aves Domésticas/enzimologia , Doenças das Aves Domésticas/genética , Doenças das Aves Domésticas/transmissão , Tempo , beta-Lactamases/genética , beta-Lactamases/metabolismo
2.
BMC Res Notes ; 12(1): 472, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370868

RESUMO

OBJECTIVES: Salmonella is the most important causes of foodborne illness especially from poultry and poultry products. So the aim of this study was to carryout phenotypic characterization, antimicrobials susceptibility pattern and risk factors of Salmonella isolates from farms and markets eggs, cloacae swabs of chickens and stool of egg collectors. A cross-sectional study was conducted from January 2018 to September 2018. Samples were, processed; Salmonella was isolated, phenotypically identified by OmniLog and antimicrobials susceptibility were carried out. RESULT: Over all; 11 (2.65%) of Salmonella enterica were phenotypically characterized out of 415 samples from farms egg content (n = 83), farms eggshell (n = 83), cloacae (n = 83), market eggshell (n = 83) and market egg contents (n = 83) with 2.4%, 0%, 2.4%, 4.8% and 3.6% prevalence, respectively. Out of isolates, 8 (72.72%) displayed multidrug resistance. All isolates showed susceptibility to Gentamicin, Kanamycin and Streptomycin. Lack of separating cracked eggs, washing hand, eggs stay longer unsold, and mixing excreta with feed were associated risk factors for Salmonella presence (P-value < 0.05). The presence of drug resistant Salmonella enterica within egg/and chicken can pose serious health problem. Good hygienic practices are important to reduce risk factors of Salmonella contamination.


Assuntos
Criação de Animais Domésticos/ética , Doenças das Aves Domésticas/epidemiologia , Salmonelose Animal/epidemiologia , Salmonella enterica/isolamento & purificação , Animais , Antibacterianos/farmacologia , Galinhas , Estudos Transversais , Ovos/microbiologia , Etiópia/epidemiologia , Fazendeiros , Fazendas , Fezes/microbiologia , Gentamicinas/farmacologia , Humanos , Higiene/educação , Canamicina/farmacologia , Testes de Sensibilidade Microbiana , Doenças das Aves Domésticas/microbiologia , Doenças das Aves Domésticas/transmissão , Prevalência , Fatores de Risco , Salmonelose Animal/microbiologia , Salmonelose Animal/transmissão , Salmonella enterica/efeitos dos fármacos , Estreptomicina/farmacologia
3.
PLoS Negl Trop Dis ; 13(7): e0007435, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31295245

RESUMO

Toxoplasma gondii is a zoonotic protozoan with a worldwide occurrence, but the determinants of the current pattern in the geographical distribution of T. gondii lineages and strains remain poorly understood. To test the influence of human trade on T. gondii populations, we conducted a population genetic study of 72 T. gondii animal isolates from Senegal, a West African country in which the ongoing inland progress of invasive murine hosts (introduced in port cities of Senegal since the 16th century by European sailors) is well described. Isolates were mainly collected on free-range poultry, which are considered as relevant bioindicators of T. gondii strain diversity in the domestic environment. Sampling was conducted in two port cities of Senegal (Dakar and Saint-Louis) and in one inland region (Kedougou). Population genetic analyses using 15 microsatellite markers revealed different patterns between port cities where lineages non-virulent for mice (type II, type III, and Africa 4) were predominant, and Kedougou where the mouse-virulent Africa 1 lineage was the most common. By considering the current spatial pattern in the inland progress of invasive rodents in Senegal, our results suggest that the invasive house mouse Mus musculus domesticus counter-selects the Africa 1 lineage in the invaded areas. The comparison of the microsatellite alleles of type II strains from Senegal to type II strains from other areas in Africa and Western Europe, using discriminant analysis of principal components and Network analysis, point to a mainly Western European origin of the type II lineage in Senegal. Collectively, these findings suggest that human-mediated intercontinental migrations of murine hosts are important vectors of T. gondii strains. Differential susceptibility of endemic and introduced murine hosts to various T. gondii strains probably determines the persistence of these strains in the environment, and therefore their availability for human and animal infection.


Assuntos
Comércio , Variação Genética , Doenças das Aves Domésticas/transmissão , Toxoplasma/genética , Toxoplasmose Animal/epidemiologia , Toxoplasmose Animal/transmissão , África Ocidental/epidemiologia , Alelos , Animais , Galinhas/parasitologia , Reservatórios de Doenças/parasitologia , Europa (Continente)/epidemiologia , Genética Populacional , Genótipo , Geografia , Humanos , Camundongos/parasitologia , Repetições de Microssatélites , Filogenia , Filogeografia , Polimorfismo de Fragmento de Restrição , Doenças das Aves Domésticas/parasitologia , Virulência
4.
Vet Microbiol ; 235: 25-34, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31282376

RESUMO

Five, class II, virulent Newcastle disease virus (vNDV) isolates of different genotypes from different host species were evaluated for their ability to infect, cause disease, and transmit to naïve chickens. Groups of five birds received a low, medium, or high dose, by the oculonasal route, of one of the following vNDV: three chicken-origin, one cormorant-origin, and one pigeon-origin. Three naïve birds were added to each group at two days post-inoculation (DPI) to evaluate transmission. Virus shedding was quantified from swabs (2/4/7 DPI), and seroconversion was evaluated at 14 DPI. All inoculated and contact birds in the chicken-origin vNDV groups succumbed to infection, displaying clinical signs typical of Newcastle disease and shed virus titers above 6 log10 EID50/ml. Birds receiving a high and medium dose of the cormorant virus showed primarily neurological clinical signs with 80% and 60% mortality, respectively. The chickens showing clinical disease shed virus at titers below 4 log10 EID50/ml, and the remaining bird in the high dose group seroconverted with a high HI titer. For the pigeon-origin virus, no clinical signs were observed in any of the birds, but all 5 chickens in the high challenge dose and one bird in the medium challenge group shed virus at mean titers of 3.1 and 2.2 log10 EID50/ml, respectively. Overall, the chicken-origin viruses infected chickens and efficiently transmitted to naïve birds, while the cormorant- and pigeon-origin viruses infected chickens only at the higher doses and did not transmit to other birds.


Assuntos
Galinhas/virologia , Columbidae/virologia , Doença de Newcastle/transmissão , Vírus da Doença de Newcastle/patogenicidade , Doenças das Aves Domésticas/transmissão , Animais , Animais Selvagens/virologia , Vacinação , Virulência , Eliminação de Partículas Virais
5.
Vet Parasitol ; 271: 1-6, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31303197

RESUMO

Heterakis gallinarum is a widely distributed cecal nematode that parasitizes gallinaceous birds including chickens and turkeys. H. gallinarum infection poses a problem for the poultry industry as the nematode egg serves as a vector for the protozoan parasite, Histomonas meleagridis, the causative agent of histomonosis. The only means of detecting H. gallinarum in the environment is microscopic identification of the eggs in soil or feces; however, H. gallinarum eggs are often mistaken for those of Ascaridia galli. Three primer sets were designed from sequences cloned from the H. gallinarum genome to develop a diagnostic PCR. Each of these primer sets amplified a single product from H. gallinarum, but were unable to amplify DNA from H. meleagridis, Ascaridia galli, or Cestode sp. H. gallinarum DNA was amplified from Lumbricus sp. (earthworms) and Alphitobius diaperinus (darkling beetles), confirming that the earthworm acts as a paratenic host for H. gallinarum and suggesting that the darkling beetle may be a carrier for this nematode.


Assuntos
Infecções por Ascaridida/veterinária , Ascaridídios/genética , Monitoramento Ambiental/métodos , Reação em Cadeia da Polimerase/veterinária , Doenças das Aves Domésticas/diagnóstico , Doenças das Aves Domésticas/parasitologia , Animais , Ascaridídios/parasitologia , Infecções por Ascaridida/diagnóstico , Besouros/parasitologia , DNA de Helmintos/genética , Oligoquetos/parasitologia , Doenças das Aves Domésticas/transmissão , Infecções Protozoárias em Animais/transmissão , Solo/parasitologia , Trichomonadida/fisiologia
6.
Poult Sci ; 98(10): 4492-4497, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31180119

RESUMO

In ovo vaccination is currently being considered as a means of delivery for live Mycoplasma gallisepticum (MG) vaccines. This study was performed to determine the transmissibility of strain F MG (FMG) from in ovo-vaccinated chicks to non-vaccinated pen mates. Eggs from an MG clean flock were incubated together for 18 D, at which point all live embryonated eggs were either not injected or administered a dilution of an FMG vaccine at 106 CFU per dose, 1 × 104 CFU per dose, 1 × 102 CFU per dose, or 1 CFU per dose. Non-injected eggs were hatched in a separate incubator. Ten non-injected, sentinel birds, and 1 in ovo-vaccinated FMG chick were placed in each of 32 isolation units located in 2 replicate rooms (8 replicates per dose). At 6 wk of age, surviving birds that had been vaccinated in ovo were removed, swabbed for FMG detection by PCR, and bled for serum plate agglutination (SPA) and ELISA testing for the presence of antibodies against MG (1, 2, 6, and all 8 in ovo-vaccinated chicks in the 106, 104, 102, and 1 CFU dosages). At 12 wk of age, the remaining sentinel birds were likewise sampled. No sentinel birds died. The in ovo-vaccinated birds that survived to 6 wk were serologically positive except for 5 birds in the 1 CFU treatment. The percentages of MG-positive sentinel birds and sentinel birds with antibody production against MG at 12 wk from each unit were not different between all MG dosages (P = 0.48, PCR; P = 0.77, SPA; P = 0.85, ELISA). Body weights of the in ovo-vaccinated chicks at 6 wk of age (P = 0.43) and the sentinel birds at 12 wk of age (P = 0.95) were each not affected by FMG treatment. These findings indicate that layer chickens in ovo vaccinated with a live-attenuated FMG vaccine were capable of transmitting FMG to other chicks with which they were in direct contact.


Assuntos
Vacinas Bacterianas/administração & dosagem , Infecções por Mycoplasma/veterinária , Mycoplasma gallisepticum/imunologia , Doenças das Aves Domésticas/transmissão , Animais , Vacinas Bacterianas/imunologia , Galinhas , Feminino , Infecções por Mycoplasma/imunologia , Infecções por Mycoplasma/transmissão , Óvulo , Doenças das Aves Domésticas/imunologia , Vacinas Atenuadas/administração & dosagem , Vacinas Atenuadas/imunologia
7.
J Vet Sci ; 20(3): e27, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-31161745

RESUMO

In 2016, novel H5N6 highly pathogenic avian influenza virus emerged in Korea. During the outbreak, the virus caused the largest culling, especially in brown chicken lines. We determined the pathogenicity and transmissibility of the virus in 2 white chicken lines of the specific pathogen-free chickens, broilers and brown chicken line of Korean native chicken (KNC). A KNC had a longer virus shedding period and longer mean death time than others. Our study showed that this characteristic in the KNC might have contributed to a farm-to-farm transmission of the brown chicken farms.


Assuntos
Vírus da Influenza A/patogenicidade , Influenza Aviária/virologia , Doenças das Aves Domésticas/virologia , Animais , Cruzamento , Galinhas/virologia , Influenza Aviária/transmissão , Doenças das Aves Domésticas/transmissão , República da Coreia , Virulência
8.
Poult Sci ; 98(10): 4441-4448, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31111928

RESUMO

This work was designed to study the dynamics of transmission of Newcastle disease virus (NDV), genotype VIId, from Muscovy ducks (Cariana moscata) infected either by intramuscular (IM) or intranasal (IN) inoculation, to in-contact broiler chickens (Gallus gallus). IM-infected Muscovy ducks (G1d) exhibited only 5% mortality, and the concentration of virus shed from the cloaca was greater and for longer period than virus shed from the trachea. In contrast, IN-infected ducks (G2d) exhibited no mortality, and virus shedding from the trachea was higher than that from the cloaca starting from 4 days post infection (dpi) and continued up to 16 dpi, while in IM-infected ducks (G1d), tracheal shedding stopped at 11 dpi. Chickens in contact with IM-infected and IN-infected ducks, G1c and G2c, respectively, not only developed severe clinical symptoms and death (80% and 20% mortality, respectively), but also shed the virus at higher concentrations than infected ducks. G1c chickens had higher viral shedding titers in both the trachea and cloaca than G2c chickens until 11 dpi. All broiler chickens infected by IM route (G3c) died, while the IN route of infection resulted in lower mortality (70%) in G4c. Generally, all IM-infected birds produced an earlier and higher level of NDV hemagglutination inhibition (HI) antibody titer, along with higher rates and shorter periods of viral shedding than those infected by the intranasal route. Our conclusion is that Muscovy ducks are efficient carriers of NDV-genotype VIId and transmit the virus to contact chickens.


Assuntos
Galinhas , Patos , Doença de Newcastle/transmissão , Vírus da Doença de Newcastle/imunologia , Doenças das Aves Domésticas/transmissão , Animais , Genótipo , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Doenças das Aves Domésticas/virologia
9.
PLoS One ; 14(5): e0216478, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31067261

RESUMO

Infectious virus-laden aerosols generated during poultry processing may mediate airborne transmissions of avian influenza at live poultry markets. To develop effective control measures to reduce aerosol dispersion, we characterised the aerosol flow pattern of the mechanical defeatherers, a major source of aerosol dispersion during poultry processing at live poultry markets in China. Mechanical defeatherers create a strong air circulation during operation with inflow and outflow velocities over 1 m/s. A partial lid was designed to suppress the outflow and reduce aerosol dispersion. Computational fluid dynamics simulations confirmed that the partial lid prototype reduced the aerosol escape rate by over 65%. To validate the effectiveness of the partial lid in reducing aerosol dispersion, a field study was conducted at a retail poultry shop in Guangzhou and the concentrations of influenza viral RNA and avian 18S rRNA dispersed in air were monitored during poultry processing, with and without the use of the partial lid. At the breathing zone of the poultry worker, the use of the partial lid effectively suppressed the upward airflow and reduced the concentration of avian 18S rRNA in the air by 57%. The economic and practical partial lid can be easily implemented to reduce generation of influenza virus-laden aerosols at live poultry markets.


Assuntos
Indústria de Processamento de Alimentos , Vírus da Influenza A , Influenza Aviária/transmissão , Influenza Humana/transmissão , Modelos Biológicos , Doenças das Aves Domésticas/transmissão , Aves Domésticas , Aerossóis , Animais , China , Humanos
10.
PLoS One ; 14(5): e0217174, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31100096

RESUMO

Extended-spectrum ß-lactamase (ESBL)- and plasmid mediated AmpC-type cephalosporinase (pAmpC)-producing Escherichia coli (ESBL/pAmpC E. coli) in food-producing animals is a major public health concern. This study aimed at quantifying ESBL/pAmpC-E. coli occurrence and transfer in Italy's broiler production pyramid. Three production chains of an integrated broiler company were investigated. Cloacal swabs were taken from parent stock chickens and offspring broiler flocks in four fattening farms per chain. Carcasses from sampled broiler flocks were collected at slaughterhouse. Samples were processed on selective media, and E. coli colonies were screened for ESBL/pAmpC production. ESBL/pAmpC genes and E. coli phylogroups were determined by PCR and sequencing. Average pairwise overlap of ESBL/pAmpC E. coli gene and phylogroup occurrences between subsequent production stages was estimated using the proportional similarity index, modelling uncertainty in a Monte Carlo simulation setting. In total, 820 samples were processed, from which 513 ESBL/pAmpC E. coli isolates were obtained. We found a high prevalence (92.5%, 95%CI 72.1-98.3%) in day-old parent stock chicks, in which blaCMY-2 predominated; prevalence then dropped to 20% (12.9-29.6%) at laying phase. In fattening broilers, prevalence was 69.2% (53.6-81.3%) at the start of production, 54.2% (38.9-68.6%) at slaughter time, and 61.3% (48.1-72.9%) in carcasses. Significantly decreasing and increasing trends for respectively blaCMY-2 and blaCTX-M-1 gene occurrences were found across subsequent production stages. ESBL/pAmpC E. coli genetic background appeared complex and bla-gene/phylogroup associations indicated clonal and horizontal transmission. Modelling revealed that the average transfer of ESBL/pAmpC E. coli genes between subsequent production stages was 47.7% (42.3-53.4%). We concluded that ESBL/pAmpC E. coli in the broiler production pyramid is prevalent, with substantial transfer between subsequent production levels.


Assuntos
Proteínas de Bactérias/metabolismo , Cefalosporinase/metabolismo , Galinhas/microbiologia , Infecções por Escherichia coli/veterinária , Transmissão Vertical de Doença Infecciosa/veterinária , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/transmissão , beta-Lactamases/metabolismo , Animais , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/transmissão , Plasmídeos , Doenças das Aves Domésticas/microbiologia
11.
Parasitol Res ; 118(7): 2311-2315, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31093752

RESUMO

The role of the American cockroach, Periplaneta americana as transport host for Eimeria tenella was evaluated. Twenty-four cockroaches were orally fed with sporulated oocysts of E. tenella. Their feces and digestive tract were examined for oocysts by sugar centrifugal flotation technique and PCR. Infectivity of the oocysts recovered from the digestive tract of infected cockroaches as well as from their feces was evaluated by orally inoculating them into Boris Brown chickens. E. tenella oocysts were found in the digestive tract and feces of infected cockroaches up to day 4 after ingestion of oocysts. Furthermore, oocysts that were recovered from the digestive tract and feces of cockroaches remained infective for 4 and 3 days after ingestion of oocysts, respectively. Presence of oocysts in the feces of chicken that had been inoculated with either digestive tract or feces of P. americana demonstrated the infectivity of E. tenella oocysts from digestive tract or feces, suggesting that P. americana may play a role in the transmission of E. tenella among chicken and between chicken flocks.


Assuntos
Galinhas/parasitologia , Coccidiose/veterinária , Eimeria tenella/isolamento & purificação , Periplaneta/parasitologia , Doenças das Aves Domésticas/transmissão , Animais , Coccidiose/parasitologia , Coccidiose/transmissão , Eimeria tenella/genética , Fezes/parasitologia , Oocistos , Doenças das Aves Domésticas/parasitologia
12.
Poult Sci ; 98(10): 5040-5044, 2019 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-31064012

RESUMO

Recent epidemiological surveys have shown that class I Newcastle disease virus (NDV) is widely distributed in China. However, little is currently known about its transmission. Therefore, in this study, we compared the transmission of class I and class II NDV. Specific-pathogen-free chickens were divided into a class I NDV inoculation group and an aerosol-exposed infection group and kept in 2 separate isolators (A and B, respectively) that were connected with an airtight plastic pipe. After inoculation, air samples were collected regularly with an All-Glass Impinger-30 (Liaoyang, China), and the airborne virus contents were analyzed using the plaque count method. In addition, oral and cloacal swabs were collected regularly to detect virus shedding using quantitative reverse transcription PCR. Similar trials were conducted simultaneously with class II NDV in isolators C and D. We consistently detected class I NDV aerosols in both isolators A and B up to 40 D post-inoculation (dpi). The aerosol concentration reached a maximum of 13.81 × 103 plague-forming units per cubic meter of air at 18 dpi and was significantly higher than that of class II NDV at 21 and 24 dpi. We also detected class I virus shedding from 2 to 40 dpi in the inoculated chickens and from 7 to 40 D post-aerosol-exposed infection in the aerosol-exposed chickens. This phenomenon may explain why class I NDV has been the primary epidemic strain of NDV in recent years.


Assuntos
Galinhas , Doença de Newcastle/transmissão , Vírus da Doença de Newcastle/fisiologia , Doenças das Aves Domésticas/transmissão , Aerossóis , Animais , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/classificação , Doenças das Aves Domésticas/virologia , Reação em Cadeia da Polimerase em Tempo Real/veterinária , Organismos Livres de Patógenos Específicos , Eliminação de Partículas Virais
13.
PLoS One ; 14(5): e0216984, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31125350

RESUMO

In the re-emergence of Highly Pathogenic Avian Influenza (HPAI), live bird markets have been identified to play a critical role. In this repeated cross-sectional study, we combined surveillance data collected monthly on Jakarta's live bird markets over a five-year period, with risk factors related to the structure and management of live bird markets, the trading and slaughtering of birds at these markets, and environmental and demographic conditions in the areas where the markets were located. Over the study period 36.7% (95% CI: 35.1, 38.3) of samples (N = 1315) tested HPAI H5 virus positive. Using General Estimation Equation approaches to account for repeated observations over time, we explored the association between HPAI H5 virus prevalence and potential risk factors. Markets where only live birds and carcasses were sold, but no slaughtering was conducted at or at the vicinity of the markets, had a significantly reduced chance of being positive for H5 virus (OR = 0.2, 95% CI 0.1-0.5). Also, markets, that used display tables for poultry carcasses made from wood, had reduced odds of being H5 virus positive (OR = 0.7, 95% CI 0.5-1.0), while having at least one duck sample included in the pool of samples collected at the market increased the chance of being H5 virus positive (OR = 5.7, 95% CI 3.6-9.2). Markets where parent stock was traded, were more at risk of being H5 virus positive compared to markets where broilers were traded. Finally, the human population density in the district, the average distance between markets and origins of poultry sold at markets and the total rainfall per month were all positively associated with higher H5 virus prevalence. In summary, our results highlight that a combination of factors related to trading and marketing processes and environmental pressures need to be considered to reduce H5 virus infection risk for customers at urban live bird markets. In particular, the relocation of slaughter areas to well-managed separate locations should be considered.


Assuntos
Virus da Influenza A Subtipo H5N1/patogenicidade , Influenza Aviária/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Animais , Galinhas/virologia , Patos/virologia , Monitoramento Ambiental , Humanos , Indonésia/epidemiologia , Vírus da Influenza A , Influenza Aviária/transmissão , Influenza Aviária/virologia , Aves Domésticas/virologia , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Fatores de Risco
14.
Avian Pathol ; 48(5): 406-415, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31090444

RESUMO

Highly contagious Newcastle disease (ND) is associated with devastating outbreaks with highly variable clinical signs among gallinaceous birds. In this study we aimed to verify clinical ND suspicions in poultry holdings in Egypt suffering from respiratory distress and elevated mortality, comparing two groups of ND-vaccinated poultry holdings in three governorates. Besides testing for Newcastle disease virus (NDV), samples were screened for infectious bronchitis virus (IBV) and avian influenza virus (AIV) by RT-qPCR as well as by non-directed cell-culture approach on LMH-cells. Virulent NDV was confirmed only in group A (n = 16) comprising small-scale holdings. Phylogenetic analysis of the fusion protein gene of 11 NDV-positive samples obtained from this group assigned all viruses to genotype 2.VIIb and point to four different virus populations that were circulating at the same time in one governorate, indicating independent epidemiological events. In group B, comprising large commercial broiler farms (n = 10), virulent NDV was not present, although in six farms NDV vaccine-type virus (genotype 2.II) was detected. Besides, in both groups, co-infections by IBV (n = 10), AIV H9 (n = 3) and/or avian reovirus (ARV) (n = 5) and avian astrovirus (AastVs) (n = 1) could be identified. Taken together, the study confirmed clinical ND suspicion in small scale holdings, pointing to inefficient vaccination practices in this group A. However, it also highlighted that, even in an endemic situation like ND in Egypt, in cases of suspected ND vaccine failure, clinical ND suspicion has to be verified by pathotype-specific diagnostic tests. RESEARCH HIGHLIGHTS Velogenic NDV circulates in small-scale poultry holdings in Egypt. Viral transmission occurred among neighbouring farms and over long distances. Co-infections with multiple pathogens were identified. Pathotype specific diagnostic tests are essential to verify ND suspicions.


Assuntos
Doença de Newcastle/epidemiologia , Vírus da Doença de Newcastle/isolamento & purificação , Doenças das Aves Domésticas/epidemiologia , Vacinação/veterinária , Vacinas Virais/imunologia , Animais , Embrião de Galinha , Galinhas , Coinfecção/veterinária , Surtos de Doenças/veterinária , Egito/epidemiologia , Feminino , Genótipo , Vírus da Bronquite Infecciosa/genética , Vírus da Bronquite Infecciosa/isolamento & purificação , Vírus da Influenza A/genética , Vírus da Influenza A/isolamento & purificação , Doença de Newcastle/prevenção & controle , Doença de Newcastle/transmissão , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Vírus da Doença de Newcastle/ultraestrutura , Filogenia , Doenças das Aves Domésticas/prevenção & controle , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Vacinas de Produtos Inativados/imunologia
15.
mSphere ; 4(2)2019 04 03.
Artigo em Inglês | MEDLINE | ID: mdl-30944215

RESUMO

Salmonella enterica subspecies enterica serovar Gallinarum biovar Pullorum (S Pullorum) is the etiological agent of pullorum disease, causing white diarrhea with high mortality in chickens. There are many unsolved issues surrounding the epidemiology of S Pullorum, including its origin and transmission history as well as the discordance between its phenotypic heterogeneity and genetic monomorphism. In this paper, we report the results of whole-genome sequencing of a panel of 97 S Pullorum strains isolated between 1962 and 2014 from four countries across three continents. We utilized 6,795 core genome single nucleotide polymorphisms (SNPs) to reconstruct a phylogenetic tree within a spatiotemporal Bayesian framework, estimating that the most recent common ancestor of S Pullorum emerged in ∼914 CE (95% confidence interval [95%CI], 565 to 1273 CE). The extant S Pullorum strains can be divided into four distinct lineages, each of which is significantly associated with geographical distribution. The intercontinental transmissions of lineages III and IV can be traced to the mid-19th century and are probably related to the "Hen Fever" prevalent at that time. Further genomic analysis indicated that the loss or pseudogenization of functional genes involved in metabolism and virulence in S Pullorum has been ongoing since before and after divergence from the ancestor. In contrast, multiple prophages and plasmids have been acquired by S Pullorum, and these have endowed it with new characteristics, especially the multidrug resistance conferred by two large plasmids in lineage I. The results of this study provide insight into the evolution of S Pullorum and prove the efficiency of whole-genome sequencing in epidemiological surveillance of pullorum disease.IMPORTANCE Pullorum disease, an acute poultry septicemia caused by Salmonella Gallinarum biovar Pullorum, is fatal for young chickens and is a heavy burden on poultry industry. The pathogen is rare in most developed countries but still extremely difficult to eliminate in China. Efficient epidemiological surveillance necessitates clarifying the origin of the isolates from different regions and their phylogenic relationships. Genomic epidemiological analysis of 97 S Pullorum strains was carried out to reconstruct the phylogeny and transmission history of S Pullorum. Further analysis demonstrated that functional gene loss and acquisition occurred simultaneously throughout the evolution of S Pullorum, both of which reflected adaptation to the changing environment. The result of our study will be helpful in surveillance and prevention of pullorum disease.


Assuntos
Evolução Molecular , Genoma Bacteriano , Doenças das Aves Domésticas/transmissão , Salmonella enterica/genética , Animais , Proteínas de Bactérias/metabolismo , Teorema de Bayes , Galinhas , China/epidemiologia , Filogenia , Polimorfismo de Nucleotídeo Único , Doenças das Aves Domésticas/microbiologia , Salmonelose Animal/transmissão , Sorogrupo , Sequenciamento Completo do Genoma
16.
Virology ; 531: 203-218, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30928699

RESUMO

In May of 2018, virulent Newcastle disease virus was detected in sick, backyard, exhibition chickens in southern California. Since, the virus has affected 401 backyard and four commercial flocks, and one live bird market in California, and one backyard flock in Utah. The pathogenesis and transmission potential of this virus, along with two genetically related and widely studied viruses, chicken/California/2002 and chicken/Belize/2008, were evaluated in both 3-week- and 62-week-old chickens given a low, medium, or high challenge dose. All three viruses were highly virulent causing clinical signs, killing all the chickens in the medium and high dose groups, and efficiently transmitting to contacts. The three viruses also replicated in the reproductive tract of the adult hens. Virus shedding for all viruses was detected 24 hours after challenge, peaking with high titers at day 4 post challenge. Although not genetically identical, the studied isolates were shown to be phenotypically very similar, which allows the utilization of the available literature in the control of the current outbreak.


Assuntos
Doença de Newcastle/transmissão , Vírus da Doença de Newcastle/fisiologia , Vírus da Doença de Newcastle/patogenicidade , Doenças das Aves Domésticas/transmissão , Fatores Etários , Animais , California/epidemiologia , Galinhas , Surtos de Doenças , Feminino , Masculino , Doença de Newcastle/epidemiologia , Doença de Newcastle/virologia , Vírus da Doença de Newcastle/genética , Vírus da Doença de Newcastle/isolamento & purificação , Doenças das Aves Domésticas/epidemiologia , Doenças das Aves Domésticas/virologia , Virulência , Eliminação de Partículas Virais
17.
Vet Microbiol ; 231: 100-106, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955795

RESUMO

Extended-spectrum beta-lactamase (ESBL) and plasmidic AmpC (pAmpC) producing Escherichia coli are found in the poultry production even without antibiotic use. The spread of these bacteria has been suggested to occur via imported parent birds, enabling transmission to production level broilers vertically via eggs. We studied transmission of ESBL/pAmpC-producing E. coli and E. coli without antibiotic selection by sampling imported parent birds (n = 450), egg surfaces prior to and after the incubation period (n = 300 and n = 428, respectively) and the laying house environment (n = 20). Samples were additionally taken from embryos (n = 422). To study the prevention of transmission, a competitive exclusion (CE) solution was added onto freshly laid eggs prior to incubation period (n = 150). Results showed carriage of ESBL/pAmpC-producing E. coli in parent birds (26.7%), the environment (5%) and egg surfaces before the incubation period (1.3%), but not from egg surfaces or embryos after the incubation period. Whole genome sequencing revealed ESBL/pAmpC-producing E. coli isolates belonging to clonal lineages ST429 and ST2040. However, the finding of E. coli cultured without antibiotic selection in two (2.2%) embryos strengthens the need to study E. coli transmission in poultry production in more depth. Since ESBL/pAmpC-producing E. coli seem not to persist on egg surfaces, there is no need to use CE solution ex ovo as a prevention method. The results indicate that other routes, such as for example transmission through fomites or horizontal gene transfer by other bacterial species, could be more important than vertical transmission in the spread of resistance in broiler production.


Assuntos
Galinhas/microbiologia , Infecções por Escherichia coli/veterinária , Escherichia coli/isolamento & purificação , Transmissão Vertical de Doença Infecciosa/veterinária , Doenças das Aves Domésticas/transmissão , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/biossíntese , Cloaca/microbiologia , Escherichia coli/enzimologia , Infecções por Escherichia coli/transmissão , Genoma Bacteriano , Óvulo/microbiologia , Aves Domésticas/microbiologia , Doenças das Aves Domésticas/microbiologia , Sequenciamento Completo do Genoma , beta-Lactamases/biossíntese
18.
PLoS One ; 14(4): e0215857, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31002703

RESUMO

BACKGROUND: From 2013 to 2017, more than one thousand avian influenza A (H7N9) confirmed cases with hundreds of deaths were reported in mainland China. To identify priorities for epidemic prevention and control, a risk assessing framework for subnational variations is needed to define the epidemic potential of A (H7N9). METHODS: We established a consolidated two-stage framework that outlined the potential epidemic of H7N9 in humans: The Stage 1, index-case potential, used a Boosted Regression Trees model to assess population at risk due to spillover from poultry; the Stage 2, epidemic potential, synthesized the variables upon a framework of the Index for Risk Management to measure epidemic potential based on the probability of hazards and exposure, the vulnerability and coping capacity. RESULTS: Provinces in southern and eastern China, especially Jiangsu, Zhejiang, Guangzhou, have high index-case potential of human infected with A (H7N9), while northern coastal provinces and municipalities with low morbidity, i.e. Tianjin and Liaoning, have an increasing risk of A (H7N9) infection. Provinces in central China are likely to have high potential of epidemic due to the high vulnerability and the lack of coping capacity. CONCLUSIONS: This study provides a unified risk assessment of A (H7N9) to detect the two-stage heterogeneity of epidemic potential among different provinces in mainland China, allowing proactively evaluate health preparedness at subnational levels to improve surveillance, diagnostic capabilities, and health promotion.


Assuntos
Epidemias/prevenção & controle , Subtipo H7N9 do Vírus da Influenza A/patogenicidade , Influenza Humana/epidemiologia , Modelos Estatísticos , Doenças das Aves Domésticas/epidemiologia , Animais , Aves , China/epidemiologia , Feminino , Humanos , Incidência , Subtipo H7N9 do Vírus da Influenza A/fisiologia , Influenza Humana/prevenção & controle , Influenza Humana/transmissão , Influenza Humana/virologia , Masculino , Densidade Demográfica , Aves Domésticas , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia , Medição de Risco , Tempo (Meteorologia)
19.
Poult Sci ; 98(8): 3176-3180, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-30953077

RESUMO

The purpose of this study was to determine if Eimeria oocysts recovered from litter at the time of chick placement in commercial broiler houses contained oocysts that were infectious for chickens. Over 100 litter samples were collected from 30 poultry farms representing a total of 60 different broiler houses with 9 houses sampled more than once over 1.5 yr. The samples were collected just before the placement of newly hatched chicks and after an anticoccidial drug (ACD) or Eimeria vaccine (VAC) program, and processed for counting oocysts followed by Eimeria species determination using ITS1 PCR. Broiler chicks were inoculated with recovered Eimeria oocysts to determine if the litter oocysts were viable and capable of causing patent infection. At placement, E. maxima (Emax) oocysts were detected in 70 of 75 houses after ACD program and 46 of 47 houses after VAC program. Eimeria acervulina, E. praecox, and/or E. tenella (Eapt) were detected in 75 of 75 houses after ACD program and 47 of 47 houses after VAC program. Viability testing revealed that 33.0% of broiler houses contained viable Emax oocysts, while 46.9% contained viable Eapt oocysts. During VAC programs, the concentration of Emax oocysts at placement and the total number of Emax oocysts shed by chickens in viability studies showed a very strong correlation (r = 0.83). Likewise, during ACD programs, the concentration of Eapt oocysts at placement and the total number of Eapt oocysts shed by chickens in the viability study showed a strong correlation (r = 0.62). In general, Eimeria oocyst levels at placement and number of viable oocysts shed by chickens in the viability study were similar among houses on the same farm. However, the number of Eimeria oocysts shed in the viability studies was considerably less than expected based on the number of oocysts given. These data suggest that nearly 100% of all poultry houses contain Emax and Eapt oocysts at placement with 30 to 50% of the houses containing viable Eimeria oocysts, thus possibly representing a source of the protozoa to newly hatched chicks.


Assuntos
Coccidiose/veterinária , Eimeria/isolamento & purificação , Oocistos/isolamento & purificação , Doenças das Aves Domésticas/transmissão , Animais , Animais Recém-Nascidos , Galinhas , Coccidiose/prevenção & controle , Coccidiose/transmissão , Coccidiostáticos/administração & dosagem , Abrigo para Animais , Doenças das Aves Domésticas/parasitologia , Doenças das Aves Domésticas/prevenção & controle , Vacinas Protozoárias/administração & dosagem , Vacinação/veterinária
20.
Transbound Emerg Dis ; 66(4): 1653-1664, 2019 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-30964232

RESUMO

Poultry can become infected with low pathogenic avian influenza (LPAI) viruses via (in)direct contact with infected wild birds or by transmission of the virus between farms. This study combines routinely collected surveillance data with genetic analysis to assess the contribution of between-farm transmission to the overall incidence of LPAI virus infections in poultry. Over a 10-year surveillance period, we identified 35 potential cases of between-farm transmission in the Netherlands, of which 10 formed geographical clusters. A total of 21 LPAI viruses were isolated from nine potential between-farm transmission cases, which were further studied by genetic and epidemiological analysis. Whole genome sequence analysis identified close genetic links between infected farms in seven cases. The presence of identical deletions in the neuraminidase stalk region and minority variants provided additional indications of between-farm transmission. Spatiotemporal analysis demonstrated that genetically closely related viruses were detected within a median time interval of 8 days, and the median distance between the infected farms was significantly shorter compared to farms infected with genetically distinct viruses (6.3 versus 69.0 km; p < 0.05). The results further suggest that between-farm transmission was not restricted to holdings of the same poultry type and not related to the housing system. Although separate introductions from the wild bird reservoir cannot be excluded, our study indicates that between-farm transmission occurred in seven of nine virologically analysed cases. Based on these findings, it is likely that between-farm transmission contributes considerably to the incidence of LPAI virus infections in poultry.


Assuntos
Galinhas , Patos , Vírus da Influenza A/fisiologia , Influenza Aviária/epidemiologia , Doenças das Aves Domésticas/epidemiologia , Perus , Criação de Animais Domésticos , Animais , Monitoramento Epidemiológico , Fazendas , Feminino , Incidência , Influenza Aviária/transmissão , Influenza Aviária/virologia , Países Baixos/epidemiologia , Doenças das Aves Domésticas/transmissão , Doenças das Aves Domésticas/virologia
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