Dead Chickens Research Articles

Avian Pathogenic Escherichia coli Isolated in Poultry Farms in Bangladesh that Use Antibiotics Extensively.

Colibacillosis caused by avian pathogenic Escherichia coli (APEC) is causing economic losses to the global poultry industry. Increased prevalence of antibiotic resistance in APEC is the leading cause for increased indiscriminate use of various antimicrobial compounds in farms. The study aimed to investigate the presence of phenotypic and genotypic markers for antibiotic resistance, metals, and biocides in APEC from Bangladeshi poultry and details about the antimicrobials used in poultry farms. In total, 55 APEC were isolated from hearts or liver samples of 86 sick or dead chickens using culture on agar plate and biochemical testing. APEC isolates were tested for antibiotic susceptibility to 14 antimicrobial agents according to the European Committee on Antimicrobial Susceptibility Testing. A series of PCRs was performed to screen the presence of genes for quinolones, colistin, aminoglycosides, ESBL, metals, and biocides. Detailed information regarding antibiotic use was collected from farmers during clinical investigations. Resistance was found to 10 antibiotics and prevalence was as follows: ampicillin (86%), ciprofloxacin (86%), trimethoprim-sulphamethoxazole (73%), chloramphenicol (33%), mecillinam (13%), gentamicin (11%), cefoxitin (11%), cefotaxime (9%), tigecycline (2%), and nitrofurantoin (2%). The most common multiresistance phenotype was CIP-AMP-SXT, and 35% of isolates were multidrug resistant. Genotypic analysis confirmed the presence of quinolone resistance genes [qnrS1 and aac-(6')-lb-cr], silver-resistant genes (silE), and mercury-resistant genes (merA) but not others. In total, 88% farmers were using different antimicrobial compounds, and, of them, 56% were using antimicrobials without prescriptions from veterinarians. Ciprofloxacin was most extensively used followed by oxytetracycline. Critically important antibiotics like ciprofloxacin, colistin, and gentamicin are extensively used in the farms. This study confirmed the presence of antibiotics, metals, and biocide-resistant APEC in poultry farms in Bangladesh. Increased resistance to quinolones is a serious ongoing problem. The indiscriminate use of antibiotics in poultry farms is alarming and should be stopped.

A comprehensive epidemiological approach documenting an outbreak of H5N1 highly pathogenic avian influenza virus clade 2.3.4.4b among gulls, terns, and harbor seals in the Northeastern Pacific

Highly pathogenic avian influenza viruses (HPAIV) H5N1 clade 2.3.4.4b continue to have unprecedented global impacts on wild birds and mammals, with especially significant mortality observed in colonial surface-nesting seabirds and in some marine mammal species. In July of 2023 H5N1 HPAIV 2.3.4.4b was detected in Caspian terns nesting on Rat Island, Washington USA. An estimated 1,800–1,900 adult terns populated the breeding colony, based on aerial photographs taken at the start of the outbreak. On a near-weekly basis throughout July and August, we counted and removed carcasses, euthanized moribund birds, and collected swab and tissue samples for diagnostic testing and next-generation sequencing. We directly counted 1,101 dead Caspian tern adults and 520 dead chicks, indicating a minimum 56% loss of the adult colony population and potential impacts to reproductive success. Combining the observed mortality on Rat Island with HPAI-related Caspian tern deaths recorded elsewhere in Washington and Oregon, we estimate that 10–14% of the Pacific Flyway population was lost in the summer of 2023. Comparatively few adult Glaucous-winged gulls (hybrids) nesting on Rat Island died (~3% of the local population), although gull chick mortality was high. Sixteen harbor seals in the immediate or nearby area stranded during the outbreak, and H5N1 HPAIV was detected in brain and/or lung tissue of five seals. These cases are the first known detections of HPAIV in a marine mammal on the Pacific coast of North America. Phylogenetic analyses support the occurrence of at least three independent avian-mammalian virus spillover events (tern or gull to harbor seal). Whole genome sequencing indicated that H5N1 HPAIV may have been introduced to Washington from Caspian terns in Oregon. Ongoing monitoring and surveillance for H5N1 HPAIV in the marine environment is necessary to understand the epidemiology of this virus, assess conservation impacts to susceptible species, and provide support for data-driven management and response actions.

Sick and Dead Chicken Detection System Based on YOLO Algorithm

Sick and Dead Chicken Detection System Based on YOLO Algorithm

Identification and Antibiotic Resistance of Pasteurella multocida Isolated from Infected Layer Chickens in West Java, Indonesia

Bacterial infections, such as those caused by Pasteurella multocida serotype A, pose significant threats to poultry farming. The use of antibiotics to treat these infections can lead to antibiotic resistance. The present study aimed to identify Pasteurella multocida from 14 Hisex Brown layer chicken hen farms, with chikens aged 25-55 weeks, in West Java, Indonesia, and to evaluate their resistance to various antibiotics. Three samples from each farm were collected from dead chickens having symptoms of fowl cholera. Initially, the study involved isolating and identifying isolates from liver, heart, and lung organs via polymerase chain reaction. The colony was then tested for antibiotic resistance using the disk diffusion method. The results showed that 13 samples were Pasteurella multocida and nine were serotype A. The test results also indicated that all isolates were resistant to colistin (10 µg) and sensitive to tetracycline (30 µg), amoxicillin (25 µg), enrofloxacin (5 µg), sulfamethoxazole (25 µg), lincomycin (109 µg), and ciprofloxacin (5 µg). The study concluded that none of the Pasteurella multocida type A isolates were any longer sensitive to colistin, with some isolates still sensitive to tetracycline, amoxicillin, enrofloxacin, sulfamethoxazole, lincomycin, and ciprofloxacin, and two isolates showing multidrug resistance patterns. Keywords: Antibiotic, Fowl cholera, Pasteurella multocida, Layer chicken

Hygiene performance rating at farm level - an auditing scheme for evaluation of biosecurity measures’ effect on prevalence of Campylobacter from selected broiler producers

BackgroundPreventing pathogens from entering the broiler premises is the main biosecurity measure at farm level. In conventional broiler production, chickens are kept indoors during the entire production period. Pathogens can enter the broiler-producing unit from sources such as water, equipment, personnel, insects, and rodents. The possible routes must be controlled, and corrective measures applied when necessary. The objective of this study was to (1) develop a hygiene protocol and test the scheme on 30 farms, and (2) compare the results to their Campylobacter-colonised status. A Hygiene Performance Rating protocol at farm level (HPR-F) was developed to systematically review the production to identify risk areas to biosecurity. The HPR-F consists of 13 categories with related questions. For each question, a score was given from 1 to 3, where 1 meant “acceptable”, 2 was “potential for improvements”, and 3 was “not acceptable”. Scores for each question were multiplied with weight factors for hygienic impact and economic consequences describing whether the necessary improvement depends on a significant investment or is a cheap quick-fix and calculated into a percentage where 100% is perfect hygiene. The 30 farms in the study were selected from one county in Norway. The Campylobacter-results for each of the 30 farms in 2019–2021 were given according to rules in the Norwegian Action Plan against Campylobacter faecal sampling on-farm 3–6 days prior to slaughter.ResultsThe overall results from the HPR-F showed that the general hygiene level was high in all farms. The mean total hygiene score was 82% and varied from 70 to 92%. The category Handling dead chicken had the highest hygiene score (93%), and Ventilation had the lowest score (55%). The HPR-F results were compared to the Campylobacter-status for the 30 farms: Campylobacter-negative flocks had slightly higher total scores than Campylobacter-positive flocks (P = 0.19). Among others, the category Outdoor area (vegetation close to the premises’ walls) was identified as the most stable factor in relation to be colonised with Campylobacter.ConclusionsThe HPR-F tested in this research trial provides a tool for veterinarians, advisors, and poultry farmers to improve biosecurity at farm level and enhance the preventive animal health initiatives.

Bottom-up effects drive the dynamic of an Antarctic seabird predator-prey system.

Understanding how populations respond to variability in environmental conditions and interspecific interactions is one of the biggest challenges of population ecology, particularly in the context of global change. Although many studies have investigated population responses to climate change, very few have explicitly integrated interspecific relationships when studying these responses. In this study, we aimed to understand the combined effects of interspecific interactions and environmental conditions on the demographic parameters of a prey-predator system of three sympatric seabird populations breeding in Antarctica: the south polar skua (Catharacta maccormicki) and its two main preys during the breeding season, the Adélie penguin (Pygoscelis adeliae) and the emperor penguin (Aptenodytes forsteri). We built a two-species integrated population model (IPM) with 31 years of capture-recapture and count data and provided a framework that made it possible to estimate the demographic parameters and abundance of a predator-prey system in a context where capture-recapture data were not available for one species. Our results showed that predator-prey interactions and local environmental conditions differentially affected south polar skuas depending on their breeding state of the previous year. Concerning prey-predator relationships, the number of Adélie penguin breeding pairs showed a positive effect on south polar skua survival and breeding probability, and the number of emperor penguin dead chicks showed a positive effect on the breeding success of south polar skuas. In contrast, there was no evidence for an effect of the number of south polar skuas on the demography of Adélie penguins. We also found an important impact of sea ice conditions on both the dynamics of south polar skuas and Adélie penguins. Our results suggest that this prey-predator system is mostly driven by bottom-up processes and local environmental conditions.

Characterization of predominant genotype (QX) of avian infectious bronchitis virus isolated from layer chickens in Bangladesh

Avian infectious bronchitis (AIB) is a highly transmissible infection that affects the poultry industry globally. This study aims to isolate and characterize emerging strains of infectious bronchitis virus (IBV) from field samples of layer chickens in Bangladesh. A total of 108 samples (trachea, lung, and kidney) were taken from dead and sick layer chickens from 18 farms in 4 areas detecting outbreaks in Bangladesh. The samples were processed and inoculated in embryonated chicken eggs (ECEs) and finally screened by the trypsin-induced hemagglutination (THA) test. Using various techniques such as hemagglutination inhibition (HI), agar gel immuno-diffusion (AGID), virus neutralization test (VNT), reverse transcription-polymerase chain reaction (RT-PCR), and nucleotide sequencing, we were able to identify and confirm the isolated IBV viruses. The study also determined the hemagglutination (HA) pattern of isolated virus using avian and mammalian red blood cells. The pathogenicity of the isolated IBV was determined using embryonated chicken eggs and day-old chicks. The study found that 8 samples were positive for IBV using ECEs, and 4 were positive by the THA test. These isolates were confirmed using HI, AGID, and VN tests. S1 gene-based RT-PCR confirmed all four isolates as IBV, with the recent isolates belonging to the genotype-QX and being similar to IBV isolates from Thailand, Saudi Arabia, and India. The HA pattern of the recent isolates showed that the isolated IBV was virulent. The pathogenicity test also revealed that the four isolates were highly pathogenic. The study indicated that the prevalent genotype (QX) of the IBV strain is present in the layer chicken population of Bangladesh.

Molecular epidemiology of infectious bronchitis virus in eastern and southern China during 2021–2023

As a highly infectious and contagious pathogen in chickens, infectious bronchitis virus (IBV) is currently grouped into nine genotypes (GI to GIX). However, the classification of serotypes of IBV is still not clear. In this study, 270 field strains of IBV were isolated from dead or diseased chicken flocks in eastern and southern China during Jan. 2021-Apr. 2023. These isolated IBV strains could be classified into two genotypes, GI (including five lineages GI-1, GI-13, GI-19, GI-22 and GI-28) and GVI based on the complete S1 sequence. Further analysis showed that the GI-19, GI-13, GI-22, GI-28 and GVI were the dominant genotypes with the proportions of 61.48%, 8.89%, 8.89%, 7.78% and 8.89% respectively, and the homology of S1 protein of these isolates ranged from 86.85% to 100% in GI-19, 92.22% to 100% in GI-13, 83.1% to 100% in GI-22, 94.81% to 100% in GI-28 and 90.0% to 99.8% in GVI, respectively. Moreover, cross-neutralization test with sera revealed that these isolates in GI-19 lineage could be classified into at least three serotypes according to the antigenic relationship. In addition, structure assay using PyMOL indicated that one mutation such as S120 in receptor binding site (RBD) of GI-19 might alter the antigenicity and conformation of S protein of IBV. Overall, our data demonstrate that not only multiple genotypes, but also multiple serotypes in a single genotype or lineage have been co-circulated in eastern and southern China, providing novel insights into the molecular evolution of the antigenicity of IBV and highlighting the significance of the selection of the dominant isolate for vaccine development in IBV endemic region.

Multidrug Resistant Pseudomonas aeruginosa Isolated from Chicken: A Public Health Concern

Infection of Pseudomonas aeruginosa has been responsible for economic losses in younger birds. This research was designed to report and document multidrug resistant P. aeruginosa recovered from chicken during infection. Sixty-seven freshly dead chicken were used in this research, the trachea, the liver, and the heart were targeted for P. aeruginosa isolation. The isolates were identified based on the cultural, morphological, and biochemical characteristics. Antimicrobial test was carried out on the pure isolates using the disc diffusion method. A total of 23 isolates of P. aeruginosa were recovered; 19 isolates were recovered from the trachea, 3 from the liver and 1 from the heart. All the isolates were showing green pigment on nutrient agar, they were all Gram-negative rods, motile, catalase and citrate positive. The result of the antibiotic susceptibility showed that ampicillin was most resisted with a resistance of 95.7% (22) while gentamicin was least resisted with 39.1% (9), and 69.5% (16) of the isolates were showing resistance to more than three antibiotics. The most encountered resistant pattern was AMP, TLY with 87%. The result from this study revealed that multidrug resistant P. aeruginosa in poultry may be emerging and serving as a reservoir for resistant P. aeruginosa gene.

Carrion type and extent of breeding success together influence subsequent carrion choice by adult burying beetles

Abstract Insects can adjust their behaviour in relation to experience in a wide range of contexts including foraging, mate selection and choice of oviposition site. Here, we investigate whether burying beetles Nicrophorus vespilloides modulate their choice of carrion type in relation to the outcome of their past breeding experience. Burying beetles require the carcass of a small vertebrate, such as a mouse or a chick, to reproduce. Beetle parents convert this carrion into an edible nursery for their larvae, whom they typically care for throughout larval development. We tested whether a beetle's past breeding experience influenced its subsequent choice of carrion when presented simultaneously with either a dead mouse or a dead chick. We found that beetles that bred on a mouse and produced many larvae in their first breeding attempt subsequently favoured mice over chicks for their second breeding attempt. Beetles that had produced fewer larvae on a dead mouse switched to favouring dead chicks in their second breeding attempt. Those that had bred on a dead chick chose carrion at random subsequently, regardless of their previous breeding success. Our general conclusion is that burying beetles can integrate different sources of information about their past breeding experience with current cues when selecting carrion for reproduction.

Rapid Dissemination of blaNDM-5 Gene among Carbapenem-Resistant Escherichia coli Isolates in a Yellow-Feather Broiler Farm via Multiple Plasmid Replicon.

Although carbapenems have not been approved for animal use, carbapenem-resistant Escherichia coli (CREC) strains are increasingly being detected in food-producing animals, posing a significant public health risk. However, the epidemiological characteristics of CREC isolates in yellow-feather broiler farms remain unclear. We comprehensively investigated the genetic features of carbapenem-resistance genes among E. coli isolates recovered from a yellow-feather broiler farm in Guangdong province, China. Among the 172 isolates, 88 (51.2%) were recovered from chicken feces (88.5%, 54/61), the farm environment (51.1%, 24/47), and specimens of dead chickens (15.6%, 41/64). All CREC isolates were positive for the blaNDM-5 gene and negative for other carbapenem-resistance genes. Among 40 randomly selected isolates subjected to whole-genome sequencing, 10 belonged to distinct sequence types (STs), with ST167 (n = 12) being the most prevalent across different sources, suggesting that the dissemination of blaNDM-5 was mainly due to horizontal and clonal transmission. Plasmid analysis indicated that IncX3, IncHI2, and IncR-X1-X3 hybrid plasmids were responsible for the rapid transmission of the blaNDM-5 gene, and the genetic surrounding of blaNDM-5 contained a common mobile element of the genetic fragment designated "IS5-△ISAba125-blaNDM-5-bleMBL-trpF-dsbC". These findings demonstrate a critical role of multiple plasmid replicons in the dissemination of blaNDM-5 and carbapenem resistance.

Nutritional muscular dystrophy in broiler thigh muscles: pathological analysis of a problem in the field

Objective. This study aims to use histopathologic method to investigate nutritional muscular dystrophy in broilers due to vitamin E deficiency. Materials and methods. Tissue samples taken from 20 dead chicks and total 28 blood samples sent by taking from diseased also eight chicks were analyzed. The amount of vitamin E determined in feed analysis was found to be 5% less than the amount declared to be present in the feed ration. Results. The average amount of α-tocopherol in blood serums was measured as 0.285 µg/g. Plasma calcium and phosphorus levels were found to be high, whereas sodium, potassium, and magnesium levels were found to be normal levels. Histopathologically, nutritional muscular dystrophy was defined in 18 of 20 chicks (90%). In the histopathologic examination of muscular sections, varying degrees of hyaline degenerations, necrosis, mineralization, lipidosis, and mononuclear cell infiltrations were observed. Conclusions. It was determined that when the fat content of the ration was increased, vitamin and mineral levels, particularly vitamin E, changed within the ration content, and the health of the chicks deteriorated, resulting in histopathologic damages in different organ tissues. The study concludes that the poultry farming industry should attach importance to feed management systems for chick’s the proper and healthy feeding.

Molecular Detection and Serological Investigation of Newcastle Disease in Intensive, Semi-Intensive, and Backyard Production Systems in Central and Southwestern Areas of Ethiopia.

The purpose of this research is to detect Newcastle disease virus and to assess the seropositivity among backyard, semi-intensive, and intensive farms located in central and southwestern areas of Ethiopia. A total of 239 oropharyngeal and cloacal swab samples were collected from symptomatic birds found in Holeta, Burayu, Jimma towns as well as Seka Chekorsa and Nadhigibe woredas of Jimma Zone. In addition, ninety blood samples were collected from wing veins of unvaccinated birds found in the study areas of Jimma zone. Side-by-side information related to risk factors estimated to contribute to the susceptibility of the disease was collected by interviewing owners of sampled birds. Reverse transcription polymerase-chain reaction (RT-PCR) was conducted to detect NDV. Likewise, Enzyme-linked immunosorbent assay (ELISA) was performed to determine the seropositivity of ND. The proportion of samples where NDV was detected was 24.6%. Similarly, 68.9% of the sampled birds were seropositive. It was observed that adult birds were more likely to encounter the disease than youngs (OR = 11.6; 95% CI: 4.0-33.3; P = 0.000). Birds owned by respondents who leave diseased birds in the flock were more likely infected (OR = 6.2; 95% CI: 1.8-21.2; P=0.004) as compared to those isolated and mode of disposal of dead chicken significantly affect exposure (OR = 0.13; 95% CI: 0.10-4.88; P = 0.044). Likewise, access to veterinary services highly likely reduces susceptibility to the disease (OR = 12.4; 95% CI: 3.2-46.9; P = 0.000). It was also found that birds farmed intensively were the most at risk (OR = 2.8; 95% CI: 0.58-13.71; P = 0.199). Detection of ND from a significant proportion of sampled birds and their high seropositivity percentage revealed the circulation of the virus in the study areas.

Impact of early feed restriction and continued supplementation with coated organic acid and essential oils on sustainability of laying performance, egg quality, fertility, hatchability, immunity status, and gut microbiota of Japanese quail hens

Abstract Three hundred and sixty, 42-day-old Japanese quail (JQ) hens were randomly divided into six experimental groups with 5 replicates/group. Each replicate consisted of 12 birds (8 females and 4 males). During the growing period, chickens were fed restricted (FR) during only the second week of age at days 7, 9, 11, and 13. Three levels of FR were applied: 0.0 (control), 12.5 (12.5FR), and 25.0% (25FR) of the ad libitum intake of chickens measured on the previous day (groups 1, 2 and 3). In the other three groups (4, 5 and 6) the control, 12.5FR and 25.0FR diets were supplemented with coated organic acid + essential oils (COAWEO ) at 100 g/ton feed. The trial lasted from 6 to 18 weeks of age. Feed intake was significantly reduced by 12.5% FR compared with the control group. FR improved all external and internal egg quality of JQ hens except for egg weight, while albumen % decreased in the group fed 12.5FR diet. Coated organic acid with essential oils did not affect all JQ hens’ external and internal egg quality. Feed restriction did not affect fertility, pipped and dead chicks, and hatchability, as total and fertile egg percentage. COAWEO increased fertility and hatchability percentage. FR did not affect blood serum biochemistry and immunity characteristics except for high density lipoprotein (HDL) and hemagglutination inhibition test for infectious bursal disease virus (HI IBDV). Coated organic acid with essential oils did not affect quail blood characteristics but significantly decreased total lipids and increased IL6 at 18 weeks of age. Dietary COAWEO decreased E. coli, Clostridia, and Salmonella while increasing Lactobacillus counts. It can be concluded that 25.0% FR supplemented with COAWEO considerably improved the sustainability of productive performance of JQ hens without adverse effects on egg production, quality, fertility and hatchability traits, serum biochemistry and immune markers, and gut microbiota.

The impact of management practices on the disease and mortality rates of broilers and layers kept by small-scale farmers in Dodoma urban district, Tanzania

The demand for chicken products in Tanzania has increased due to population growth and rising incomes. As a result, the production of broilers and layers has been promoted to fill the gap due to their high productivity. However, exotic breeds of chicken are susceptible to diseases, thus requiring good disease management practices. The current study aimed to increase production of exotic breeds of chicken in the Dodoma region, which is growing rapidly, by identifying management factors associated with disease and chicken mortality. One hundred and four households that keep broilers or layers were selected randomly from the Dodoma urban district. The households were interviewed to gather information about chicken diseases, mortality, and management practices. The proportion of sick and dead chickens per farm was determined and used in beta regression to test its association with management practices and chicken breed. The proportion of sick chickens in a flock was low when stocking density was low and in large households, but it was higher when the farmer lacked knowledge of disease management. Further, mortality rates were high when farmers lacked disease knowledge and cleaning frequency was low, and low when farmers had extensive experience in chicken production. Improvement of extension services and education programmes for poultry farmers on good disease management practices is necessary to increase the production of layers and broilers in the region.

Emergence of Salmonella Infantis carrying the pESI megaplasmid in commercial farms of five major integrated broiler operations in Korea

Considering Salmonella transmission occurs through several routes in integrated broiler operations, control of nontyphoidal Salmonella in commercial farms is essential. This study aimed to compare the distribution of persistent Salmonella serovars in environments and dead chickens between 5 major integrated broiler operations in Korea. The prevalence of Salmonella-positive farms in dust prior to placement by operations was 0 to 25%, but the prevalence in dust and feces at the time of depletion was increased to 16.7 to 41.7% and 16.7 to 66.7%, respectively. Moreover, the prevalence of farms with Salmonella in chickens that died within 1 week old and at 4 to 5 weeks old ranged from 8.3 to 58.3% and 16.7 to 41.7%, respectively. The prevalence of Salmonella enterica serovar Infantis-positive farms in dust prior to placement and in chickens that died within 1 week old was 5.2 and 3.4%, respectively, but the prevalence in dust and feces at the time of depletion and in chickens that died at 4 to 5 weeks old was significantly increased to 27.6, 41.4, and 20.7%, respectively (P < 0.05). Interestingly, the plasmid of emerging S. Infantis (pESI) was only identified in S. Infantis, and the prevalence of multidrug-resistance was significantly higher in pESI-positive S. Infantis (99.2%) than in pESI-negative S. Infantis (6.7%) (P < 0.05). The distribution of pulsotypes between pESI-positive and pESI-negative S. Infantis were varied, but a majority of S. Infantis were clustered only 2 pulsotypes. Moreover, pESI-positive S. Infantis harbored more virulence factors than pESI-negative S. Infantis. This study is the first report on characteristics of S. Infantis carrying the pESI plasmid in commercial broiler farms in Korea.

Dissemination of mcr-1 and β-lactamase genes among Pseudomonas aeruginosa: molecular characterization of MDR strains in broiler chicks and dead-in-shell chicks infections

ObjectivesPseudomonas aeruginosa (P. aeruginosa) is one of the most serious pathogens implicated in antimicrobial resistance, and it has been identified as an ESKAPE along with other extremely significant multidrug resistance pathogens. The present study was carried out to explore prevalence, antibiotic susceptibility phenotypes, virulence-associated genes, integron (int1), colistin (mcr-1), and β-lactamase resistance' genes (ESBls), as well as biofilm profiling of P. aeruginosa isolated from broiler chicks and dead in-shell chicks.DesignA total of 300 samples from broiler chicks (n = 200) and dead in-shell chicks (n = 100) collected from different farms and hatcheries located at Mansoura, Dakahlia Governorate, Egypt were included in this study. Bacteriological examination was performed by cultivation of the samples on the surface of both Cetrimide and MacConkey’s agar. Presumptive colonies were then subjected to biochemical tests and Polymerase Chain Reaction (PCR) targeting 16S rRNA. The recovered isolates were tested for the presence of three selected virulence-associated genes (lasB, toxA, and exoS). Furthermore, the retrieved isolates were subjected to phenotypic antimicrobial susceptibility testing by Kirby–Bauer disc diffusion method as well as phenotypic detection of ESBLs by both Double Disc Synergy Test (DDST) and the Phenotypic Confirmatory Disc Diffusion Test (PCDDT). P. aeruginosa isolates were then tested for the presence of antibiotic resistance genes (ARGs): int1, mcr-1, and ESBL genes (OXA-10, OXA-2, VEB-1, SHV, TEM, and CTX-M). Additionally, biofilm production was examined by the Tube Adherent method (TA) and Microtiter Plate assay (MTP).ResultsFifty –five isolates were confirmed to be P. aeruginosa, including 35 isolates from broiler chicks and 20 isolates from dead in-shell chicks. The three tested virulence genes (lasB, toxA, and exoS) were detected in all isolates. Antibiogram results showed complete resistance against penicillin, amoxicillin, ceftriaxone, ceftazidime, streptomycin, erythromycin, spectinomycin, and doxycycline, while a higher sensitivity was observed against meropenem, imipenem, colistin sulfate, ciprofloxacin, and gentamicin. ESBL production was confirmed in 12 (21.8%) and 15 (27.3%) isolates by DDST and PCDDT, respectively. Antibiotic resistance genes (ARGs): int1, mcr-1, and ESBL genes (OXA-10, SHV, TEM, and CTX-M), were detected in 87.3%, 18.2%, 16.4%, 69.1%, 72.7%, and 54.5% of the examined isolates respectively, whereas no isolate harbored the OXA-2 or VEB-1 genes. Based on the results of both methods used for detection of biofilm formation, Kappa statistics [kappa 0.324] revealed a poor agreement between both methods.Conclusionsthe emergence of mcr-1 and its coexistence with other resistance genes such as β-lactamase genes, particularly blaOXA-10, for the first time in P. aeruginosa from young broiler chicks and dead in-shell chicks in Egypt pose a risk not only to the poultry industry but also to public health.Graphical

Seroprevalence and molecular detection of infectious laryngotracheitis virus (ILTV) in commercial chicken in Gazipur district of Bangladesh

Infectious laryngotracheitis (ILT) is one of the major diseases of chickens that cause great economic losses in commercial chicken farms. It is caused by the infectious laryngotracheitis virus (ILTV). This research work was designed to investigate the seroprevalence of ILTV in commercial chicken farms in Gazipur district. A total of 590 blood sera were collected randomly from commercial chicken farms from different locations in Gazipur district. An antigen-coated indirect ELISA was performed to determine the antibody titer against ILTV in these sera. Moreover, gross and histopathological changes in different organs were investigated. Polymerase chain reaction (PCR), a molecular detection method, was performed to detect the fragment of the glycoprotein ‘C’ (gC) gene of ILTV in the infected chicken. Overall, 195 out of 590 serum samples were positive for anti-ILTV IgG, representing 33.05% of positive cases. The highest mean titer of ILTV antibody was found in anti-ILTV-vaccinated layer chickens with a mean titer of 3554. In seasonal variation, the highest prevalence of ILTV was recorded during the winter, followed by the rainy and summer seasons. The prevalence of ILTV was the highest at the age of 10-30 weeks in layer chickens. Necropsy findings of dead chickens showed severe congestion and fibrosis in the lungs and trachea, with occlusion of the tracheal lumen by mucus, caseous exudates and blood. Microscopically, hemorrhage and huge infiltrations of inflammatory cells were found in trachea and lungs. Moreover, the nucleotide sequence of ‘gC’ gene of ILTV was amplified successfully and yielded 1.26 kbp amplicons. This study suggested that ILTV was endemic in Gazipur district and the PCR technique is a useful molecular tool for diagnosis of ILTV in the commercial chicken industry. Ann. Bangladesh Agric. (2023) 27 (1): 121-135

Phylogenetic analysis of Eimeria tenella isolates from chicken of sub-tropical mountains of Meghalaya, India.

Coccidiosis is the most common and pathogenic intestinal disease caused by different species of Eimeria is chicken. In this study, we describe the prevalence, molecular diagnosis and evolutionary insight of Eimeria tenella in chicken of Meghalaya's sub-tropical mountainous area. Faecal samples (337 no.) and dead chicks (298 no.) were collected every month from January to July' 2023 from poultry farms (4nos.) in and around Umiam, Ri-Bhoi, Meghalaya. The chicks were categorized into different age groups viz. < 3, 3-6 and > 6 weeks. Samples were examined by flotation techniques and post-mortem. The oocysts were sporulated in 2.5% potassium dichromate solution. Eimeria tenella's 18S rRNA gene genomic DNA was extracted, amplified, and sequenced. Fecal sample and postmortem examinations revealed 24.04% and 33.22% infections of Eimeria sp., respectively. Oocyst per gram (OPG) was recorded highest and lowest in July (26,500) and February (9800), respectively. Amplification of the 18S rRNA small subunit gene (SSU) by Polymerase Chain Reaction (PCR) revealed a 1790bp band size. The amplicon was sequenced and deposited in the NCBI database. BLAST analyses of the SSU rRNA gene of E. tenella, Umiam, Meghalaya isolate (OR458392.1) revealed sequence similarities of more than 99% with SSU rRNA gene sequences available in the NCBI database. Pair wise alignment exhibited nucleotide homology ranging from 71.59 to 100.0% with the maximum sequence homology (100.0%) shared with the E. tenella isolate from Turkey (HQ680474.1) and the lowest homology of 95.6% with UK (HG994972.1). Umiam isolate were found to have 97.08% and 100.0% nucleotide similarities with E. tenella from both the UK (AF026388.1) and the USA (U40264.1), respectively. However, nucleotide similarities of 98.24%, 85.33%, 84.75% and 81.35% were observed with E. tenella strain Bangalore (JX312808.1), E. tenella isolate Kerala-1 (JX093898.1), E. tenella isolate Kerala-3 (JX093900.1) and E. tenella isolate Kerala-2 (JX093899.1), respectively. Phylogenetic analysis of SSU rRNA sequences of E. tenella Umiam, Meghalaya isolate with cognate sequences throughout the world revealed these sequences are distinct but at the same time share a close phylogenetic relationship with Indian isolates from Bangalore and Andhra Pradesh. In addition, the distant phylogenetic relationship was observed with cognate gene sequences of United States of America, Canada, China. Phylogenetic analysis of SSU rRNA sequences of E. tenella Umiam, Meghalaya isolate with cognate sequences throughout the world revealed these sequences are distinct but at the same time share a close phylogenetic relationship with Indian isolates from Bangalore and Andhra Pradesh. Distant phylogenetic relationship was observed with cognate gene sequences of United States of America, Canada, China.

Characterization of infectious laryngotracheitis virus isolated from commercial layer chickens in Bangladesh during the year 2021-2022.

Infectious laryngotracheitis virus (ILTV) is responsible for causing infectious laryngotracheitis (ILT), which is a rapidly spreading and extremely transmissible disease in chickens. The current research aims to isolate and characterize ILTV from layer chickens in Bangladesh. A total of 345 samples (trachea, larynx, and lungs) were collected from ILT-suspected dead and sick layer chickens of 32 ILT-suspected farms in three different outbreak districts (Gazipur, Tangail, and Mymensingh) of Bangladesh during the outbreak year 2021-2022. Rapid detection kits examined the samples for avian influenza virus (AIV) and Newcastle disease virus (NDV). ILTV-specific primers were used to screen 72 NDV- and AIV-negative samples by polymerase chain reaction (PCR). Using chorioallantoic membrane (CAM), the study isolated the ILT virus from 9 to 10-day-old seronegative embryonated chicken eggs (ECEs) using selected PCR-positive samples. The virus was confirmed using nucleotide sequencing, agar gel immunodiffusion test (AGIDT), viral neutralization test (VNT), and pathogenicity evaluations using mortality index for chicken embryos (MICEs) and intra-tracheal pathogenicity index (ITPI). The results indicated that among the PCR-positive 10 samples, only two (Alim_ILT_1001 and Alim_ILT_1,000) were found positive using ECEs. There were two field isolates of ILTVs, as shown by the amplicon size of the ICP4 gene-based PCR. A phylogenetic study of the ICP4 gene revealed that the recent isolates have a close similarity with the ILTV isolates of Turkey, Bangladesh, and Australia. AGIDT revealed strong precipitation lines due to ILTV-specific antibodies reacting with field viruses, while VNT neutralized both isolates with conventional ILTV antibodies. The pathogenicity testing indicated that Alim_ILT_1001 had MICE and ITPI values of 0.77 and 0.63, whereas Alim_ILT_1,000 had 0.71 and 0.57. Both the ILTV isolates have similarities with the isolates of Turkey, Bangladesh, and Australia, and they are highly virulent for chickens.