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BACKGROUND: The chicken body louse is an obligate ectoparasite of domestic chickens. Chicken body lice feed on feathers, and infestation with this louse is linked to decreases in egg production, hen weight, and feed conversion efficiency. However, it is unknown how chicken body lice impact egg-laying chickens in cage-free environments. Welfare and behavior metrics were collected from flocks of egg-laying chickens either infested with chicken body lice or left uninfested. METHODS: In two trials, two flocks of cage-free commercial egg-laying chickens were infested with chicken body lice or maintained as uninfested controls. At three timepoints, behavior and welfare of all chickens was measured. On-animal sensors were used to quantify pecking, preening, and dustbathing behavior. Other animal-based welfare metrics included recording comb wounds and skin lesions. RESULTS: Birds infested with chicken body lice exhibited significantly more preening behaviors than uninfested birds, even at low louse levels. Moderate or severe skin lesions were detected on birds that were moderately infested with chicken body lice while skin lesions were never detected on uninfested birds. CONCLUSIONS: The welfare of chickens was impacted by the chicken body louse, a chewing louse that primarily feather feeds. Evidence of skin lesions on infested birds suggests that lice may cause more damage to birds than previously thought, and further evaluation of louse economic damage is necessary.

Infectious bronchitis virus (IBV) induces severe economic losses in chicken farms due to the emergence of new variants leading to vaccine breaks. The studied IBV strains belong to Massachusetts (Mass), Canadian 4/91, and California (Cal) 1737 genotypes that are prevalent globally. This study was designed to compare the impact of these three IBV genotypes on primary and secondary lymphoid organs. For this purpose, one-week-old specific pathogen-free chickens were inoculated with Mass, Canadian 4/91, or Cal 1737 IBV variants, keeping a mock-infected control. We examined the IBV replication in primary and secondary lymphoid organs. The molecular, histopathological, and immunohistochemical examinations revealed significant differences in lesion scores and viral distribution in these immune organs. In addition, we observed B-cell depletion in the bursa of Fabricius and the spleen with a significant elevation of T cells in these organs. Further studies are required to determine the functional consequences of IBV replication in lymphoid organs.

Exposure to heat stress can cause a significant increase in the death rate and disease susceptibility of poultry birds, ultimately impacting the profitability of the poultry industry. Despite being a more economical choice, Japanese quails (Coturnix japonica) are not immune to the harmful effects of heat stress. Quails may experience negative effects on their reproductive performance due to excessive reactive molecules caused by heat stress. However, they have developed various mechanisms to maintain their reproductive abilities in such conditions. The neuroendocrine system in birds plays a vital role in regulating their reproductive responses to thermal stress, and it is also connected to other environmental factors such as photoperiod that can impact their reproductive performance. Hormones are crucial in the complex interactions necessary for sexual maturation and reproductive responses to heat stress in Japanese quails living in stressful thermal conditions. [ABSTRACT FROM AUTHOR]

Simple Summary: Ellagic acid, extracted from medicinal foods like raspberries and pomegranates, enhances poultry production and disease resistance by regulating redox, inflammation, and cell death. However, the research on ellagic acid in poultry is nascent, with unclear mechanisms. This mini-review summarizes the latest 10-year findings to promote the practical use of ellagic acid in maintaining poultry health and formulating strategies. It has been approximately 2000 years since the medicinal homologous theory, which primarily holds that food has the same therapeutic value as medicine in order to improve the health of both humans and animals. In recent years, this theory has also been proposed to be used in poultry breeding. Ellagic acid (EA), a natural compound primarily extracted from medicinal homologous foods such as raspberries and pomegranates, is reported to have incomparable advantages in improving the production performance and disease resistance of poultry due to its pharmacological properties, which regulate the processes of redox homeostasis, inflammatory response, and cell apoptotic death. However, the application and research of EA in poultry production are still in the initial stage, and the potential mechanisms of its biological functions affecting animal health have not been clearly identified, which requires more attention worldwide. This mini-review collects the latest 10-year achievements of research on the effects of EA on poultry health, aiming to promote the practical application of EA in maintaining animal health and formulating corresponding targeted strategies. [ABSTRACT FROM AUTHOR]

This study aimed at assessing the experiences of people living with HIV who participated in an agricultural livelihood support initiative in selected districts of Uganda. The initiative, implemented from 2017 to 2018, involved the provision of agricultural inputs such as beans, cassava cuttings, goats, chickens, and pigs to participants. In-depth interviews were conducted with 37 people (28 women and 9 men) from the districts of Kampala, Masaka and Wakiso (specifically Entebbe) in central Uganda, who had participated in the project. Data were analysed thematically focusing on facilitators, challenges and outcomes from the project. The following themes emerged as facilitators: access to land and animal feed, prior farming experience and supportive family and friends. Some participants experienced challenges including animal/poultry diseases, livestock theft, “low quality” agricultural inputs, unfavourable weather conditions, limited finance and land to support livelihood activities and difficulties working in groups. Several participants reported positive livelihood outcomes including improved food security, better nutrition, increased income and improved mental health. However, some participants reported negative outcomes which took the form of a loss of money and time invested when their livestock died from disease. Although participants in the agricultural livelihood initiative faced challenges which reduced the profitability of their projects, the initiative was regarded as beneficial and worthwhile. These findings have relevance to the broader field of livelihoods programming. Future interventions can draw from the experiences of our participants while also taking seriously into consideration the different circumstances of individuals in a targeted population so as to increase the chances of producing more positive outcomes. [ABSTRACT FROM AUTHOR]

To determine the flock's economic worth, free‐range chicken growers must determine the gender, bird movement, behavior, disease detection, and lameness of the chickens. However, because of the complex environmental background and the fluctuating chicken population, it is difficult for farmers to effectively and properly measure those characteristics. Manual estimation is also inaccurate and time‐consuming because probable identification occurs in their life cycle. Therefore, the industry benefits from automated systems that can produce findings quickly and precisely in managing health and diseases. The advancement of machine learning (ML)– and deep learning (DL)–based algorithms are boons for poultry health and disease management. This study reviews the literature using ML and DL techniques in prediction, classification, and disease detection in various metrics, namely, poultry health and disease management. We have considered the research article published from 2010 to 2023 in this study, which uses ML‐ and DL‐based computation techniques in poultry welfare metrics such as gender identification, tracking of poultry, analysis of broiler chicken behavior, detection of poultry diseases, lameness and broiler weight, and stress monitoring. In addition, this review explores the most recent developments, difficulties, strategies, and databases used in image preprocessing feature extraction and classification. The review addresses these challenges and discusses the approaches and techniques researchers employ to tackle them in the field of poultry management and disease detection. [ABSTRACT FROM AUTHOR]

Since the discovery of viruses, humans have always faced a great challenge in dealing with their subsequent diseases. Coronaviruses have created huge challenges in the world. Coronaviruses are RNA genome viruses from the Coronaviridae family that can cause different diseases in both poultry and humans, but no evidence has been provided for their zoonotic potential, which may be due to the different genera of the viruses that cause diseases in these hosts. There are different ways of transmission for the coronaviruses with airborne being the most common and important route. However, the role of migratory birds in their spread has been recently noticed. Due to the novelty and importance of this issue, we decided to conduct a review study on the role of migratory birds in the spread of coronaviruses. The results show that due to the high possibility of the virus mutations in the host's body, the interspecies barrier can be broken and we can see the direct transmission of the coronaviruses from birds to humans. However, due to the novelty of this topic, more studies are required to acquire a comprehensive knowledge on this matter. [ABSTRACT FROM AUTHOR]

Newcastle disease (ND), an infectious illness, affects domestic and wild birds. Poultry production in Mali faces significant obstacles due to this disease. An important cause of loss in Mali's chicken industry, especially in rural areas, is Newcastle disease, with the sole method of prevention being vaccination. Unfortunately, in village poultry farms, this vaccination coverage is very low. This study aims to determine the effectiveness of hyper-immune egg yolk in protecting against Newcastle disease in poultry, as a cheaper and more accessible means of prophylaxis. Forty-five-day-old seronegative chickens (Leghorn strain) were divided into three groups (n = 5) housed separately. Groups I and II were inoculated with the virulent Newcastle strain (Ml029/07) titrating 106 EID50/ml intramuscularly, 100 µl per chicken; thereafter, group I was treated with hyper-immune egg yolk intramuscularly, 2 ml for 3 days. Group III (the control group) received neither virus nor treatment. All groups were placed under clinical observation for 14 days. All chickens in groups I and III remained healthy and recorded no mortality during the entire period, while group II showed signs of ND and had 100% mortality. The hyper-immune egg yolk was able to protect poultry against the ML029/07 strain isolated in Mali. Further studies are recommended, with interventions to make this method of prevention more accessible in areas with poultry populations as a means of protection against ND mortalities. [ABSTRACT FROM AUTHOR]

Necrotic enteritis (NE) is an enteric disease of poultry that alters the structure of the gut microbial community causing dysbiosis. This 28 day experiment investigated the effects of 125% and 135% arginine diets on the gut microbial diversity and composition of broilers during a subclinical NE challenge. One hundred and twenty one-day-old chicks were randomly allocated to 4 treatments with six replicates each-Uninfected + Basal, NE + Basal, NE + Arg 125%, and NE + Arg 135% diet groups. NE was induced by inoculating 1 × 104 E. maxima sporulated oocysts on day 14 and 1 × 108 CFU C. perfringens on days 19, 20, and 21 of age. The NE challenge significantly decreased the number of observed amplicon sequence variants (p = 0.03), the abundance of the phylum Firmicutes (p < 0.01), and the species Mediterraneibacter cottocaccae (p = 0.01) in the ceca of birds on day 21. The NE challenge significantly increased the Bray-Curtis index (p < 0.01), and the abundance of the phylum Bacteroidota (p < 0.01), family Odoribacteraceae (p < 0.01), genus Odoribacter (p < 0.01), and species O. splanchnicus (p = 0.01) on day 21. During NE, the 125% arginine diet restored the abundance of the phylum Bacteroidota (p = 0.03), family Odoribacteraceae (p = 0.03) and Oscillospiraceae (p = 0.03), genus Odoribacter (p = 0.03), and species O. splanchnicus (p = 0.03) and M. cottocaccae (p < 0.01) on day 21. The 135% arginine diet effectively restored the loss in alpha diversity (p = 0.01) caused by NE, the abundance of the phylum Firmicutes (p = 0.01) and Bacteroidota (p < 0.01), family Oscillospiraceae (p = 0.03) and Odoribacteraceae (p < 0.01), genus Odoribacter (p < 0.01), and species O. splanchnicus (p < 0.01) and M. cottocaccae (p < 0.01) on day 21. On day 28, the treatments had a significant effect on the cecal propionate (p = 0.01), butyrate (p = 0.04), and total SCFA (p = 0.04) concentrations. In conclusion, the 125% and 135% arginine diets restored gut microbial composition during a subclinical NE challenge, but not the cecal SCFA profile. Hence, arginine in combination with other feed additives could be used in restoring gut microbial homeostasis during NE in poultry. [ABSTRACT FROM AUTHOR]

The poultry industry, a cornerstone of global food security, faces dynamic challenges exacerbated by viral diseases. This review traces the trajectory of poultry vaccination, evolving from traditional methods to the forefront of innovation Virus-Like Particle (VLP) vaccines. Vaccination has been pivotal in disease control, but traditional vaccines exhibit some limitations. This review examines the emergence of VLPs as a game-changer in poultry vaccination. VLPs, mimicking viruses without replication, offer a safer, targeted alternative with enhanced immunogenicity. The narrative encompasses VLP design principles, production methods, immunogenicity, and efficacy against major poultry viruses. Challenges and prospects are explored, presenting VLP vaccines as a transformative technique in poultry disease control. Understanding their potential empowers industry stakeholders to navigate poultry health management with precision, promising improved welfare, reduced economic losses, and heightened food safety. [ABSTRACT FROM AUTHOR]

As part of the response to the highly pathogenic avian influenza A(H5N1) virus outbreak in U.S. cattle and poultry and the associated human cases, CDC and partners are monitoring influenza A virus levels and detection of the H5 subtype in wastewater. Among 48 states and the District of Columbia that performed influenza A testing of wastewater during May 12–July 13, 2024, a weekly average of 309 sites in 38 states had sufficient data for analysis, and 11 sites in four states reported high levels of influenza A virus. H5 subtype testing was conducted at 203 sites in 41 states, with H5 detections at 24 sites in nine states. For each detection or high level, CDC and state and local health departments evaluated data from other influenza surveillance systems and partnered with wastewater utilities and agriculture departments to investigate potential sources. Among the four states with high influenza A virus levels detected in wastewater, three states had corresponding evidence of human influenza activity from other influenza surveillance systems. Among the 24 sites with H5 detections, 15 identified animal sources within the sewershed or adjacent county, including eight milk-processing inputs. Data from these early investigations can help health officials optimize the use of wastewater surveillance during the upcoming respiratory illness season. [ABSTRACT FROM AUTHOR]

RESEARCH HIGHLIGHTSAvian pathogenic Escherichia coli (APEC) is a significant cause of morbidity, mortality, and production loss to the poultry industry worldwide. Here, we characterized 569 E. coli isolates from avian-diagnosed colibacillosis cases from the state of Georgia, USA. In total, 339 isolates were assigned into 32 serogroups with the majority classifying as O78, O2, O25, O8, O1, O86, O18, and O15. Serogroup O25 was found to link with broilers, while broiler breeders were more often associated with serogroup O1 and pet/ hobby birds with serogroup O8. In addition, some serogroups (O1) were more prevalent in the summer and fall. Analysis for virulence-associated genes (VAGs) found 23.20% of isolates did not harbour any genes linked with the APEC pathotype, while ColV plasmid-associated genes (iroN, ompT, hlyF, iss, and aerJ) were frequently detected among most isolates (with 80–96% prevalence) and some of these genes were linked with serogroup. Phylogenetic analysis, classified isolates into phylogenetic groups B2 (34%), F (19%), A (15%), and G (9%). The phylogenetic group B2 isolates also harboured the highest number of VAGs. This study highlights that the current APEC-causing disease in birds in the State of Georgia has identified several emerging serogroups possessing several VAGs that could potentially lead to challenges in colibacillosis control.Several emerging APEC serogroups were observed in Georgia poultry populations.An association between APEC serogroups and bird type was observed.The prevalence of different APEC serogroups was influenced by season.A multiplex PCR assay targeting common serogroups of APEC in Georgia poultry was developed.Several emerging APEC serogroups were observed in Georgia poultry populations.An association between APEC serogroups and bird type was observed.The prevalence of different APEC serogroups was influenced by season.A multiplex PCR assay targeting common serogroups of APEC in Georgia poultry was developed. [ABSTRACT FROM AUTHOR]

Aims Characterize global genomic features of 86 genomes of Salmonella Gallinarum (SG) and Pullorum (SP), which are important pathogens causing systemic infections in poultry. Methods and results All genomes harbored efflux pump encoding gene mdsA and gold tolerance genes golS and golT. Aminoglycoside (aac(6′)-Ib, aadA5, aph(6)-Id, aph(3′')-Ib, ant(2′')-Ia), beta-lactam (bla TEM-1, bla TEM-135), efflux pump (mdsB), fosfomycin (fosA3), sulfonamide (sul1, sul2), tetracycline [ tet(A) ], trimethoprim (dfrA17), acid (asr), and disinfectant (qacEdelta1) resistance genes, gyrA, gyrB , and parC quinolone resistance point mutations, and mercury tolerance genes (mer) were found in different frequencies. Additionally, 310 virulence genes, pathogenicity islands (including SPI-1, 2, 3, 4, 5, 6, 9, 10, 12, 13, and 14), plasmids [IncFII(S), ColpVC, IncX1, IncN, IncX2, and IncC], and prophages (Fels-2, ST104, 500465-1, pro483, Gifsy-2, 103 203_sal5, Fels-1, RE-2010, vB_SenS-Ent2, and L-413C) were detected. MLST showed biovar-specific sequence types, and core genome MLST showed country-specific and global-related clusters. Conclusion SG and SP global strains carry many virulence factors and important antimicrobial resistance genes. The diverse plasmids and prophages suggest genetic variability. MLST and cgMLST differentiated biovars and showed profiles occurring locally or worldwide. [ABSTRACT FROM AUTHOR]

Following the detection of highly pathogenic avian influenza (HPAI) virus in countries bordering Kenya to the west, we conducted surveillance among domestic and wild birds along the shores of Lake Victoria. In addition, between 2018 and 2020, we conducted surveillance among poultry and poultry workers in live bird markets and among wild migratory birds in various lakes that are resting sites during migration to assess introduction and circulation of avian influenza viruses in these populations. We tested 7464 specimens (oropharyngeal (OP) and cloacal specimens) from poultry and 6531 fresh fecal specimens from wild birds for influenza A viruses by real-time RT-PCR. Influenza was detected in 3.9% (n = 292) of specimens collected from poultry and 0.2% (n = 10) of fecal specimens from wild birds. On hemagglutinin subtyping, most of the influenza A positives from poultry (274/292, 93.8%) were H9. Of 34 H9 specimens randomly selected for further subtyping, all were H9N2. On phylogenetic analysis, these viruses were genetically similar to other H9 viruses detected in East Africa. Only two of the ten influenza A-positive specimens from the wild bird fecal specimens were successfully subtyped; sequencing analysis of one specimen collected in 2018 was identified as a low-pathogenicity avian influenza H5N2 virus of the Eurasian lineage, and the second specimen, collected in 2020, was subtyped as H11. A total of 18 OP and nasal specimens from poultry workers with acute respiratory illness (12%) were collected; none were positive for influenza A virus. We observed significant circulation of H9N2 influenza viruses in poultry in live bird markets in Kenya. During the same period, low-pathogenic H5N2 virus was detected in a fecal specimen collected in a site hosting a variety of migratory and resident birds. Although HPAI H5N8 was not detected in this survey, these results highlight the potential for the introduction and establishment of highly pathogenic avian influenza viruses in poultry populations and the associated risk of spillover to human populations. [ABSTRACT FROM AUTHOR]

Background: Infectious bronchitis (IB) is an important disease of poultry, and vaccination is the best method of preventing IB in the poultry industry worldwide. Objectives: This study was designed to evaluate cytokine and acute‐phase protein (APP) responses and their correlations with antibody titres following vaccination regimes against IB in the broiler. Materials and Methods: Broilers were vaccinated with H120 and 1/96 vaccine strains, and MIX (H120 + 1/96) vaccine strains on Days 0 and 14. Heterophils/lymphocyte (H/L) ratio, APPs including chicken serum amyloid A (SAA), chicken pentraxin 3 (chPTX3), chicken interleukin 1β (IL‐1β), chicken interleukin 6 (IL‐6) levels and antibody titres were measured. Results: An increase in the H/L ratio, SAA, chPTX3, IL‐1β and IL‐6 levels in vaccinated groups was observed 1 day after the first (highest rates) and second (lower levels) vaccination up to 3 days in three different patterns and then started to decrease. The results showed an immediate, short‐lived response and moderate increases in all criteria. Changing patterns of APPs were different but in similar pattern after the first and second immunization in vaccinated groups. A positive correlation between all criteria values on Days 1 and 15 with antibody titres on Day 28 may indicate agonistic cross‐regulation. Conclusion: Different types of IB vaccines could induce different patterns of APPs responses, which can be used to evaluate immune response outcomes in vaccine design, development and administration. The IL‐6 with the highest increase can be a sensitive parameter and chPTX3 with the high increase could be an important criterion. [ABSTRACT FROM AUTHOR]

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Importance: Infectious bursal disease (IBD) is an important viral poultry disease that vaccination can control. Objective: This study examined the immune protection of immune-complex (Vaccine A) and attenuated live (Vaccine B) IBD vaccines in specific-pathogen-free (SPF) chickens against a novel Malaysian variant IBD virus (vaIBDV) challenge. Methods: One-day-old (n =75) SPF chickens were divided randomly into the following three groups of 25 chicks each: Control, Vaccine A, and Vaccine B groups. The vaIBDV strain, UPM1432/2019, was used for the challenge at 21 and 28days post-vaccination (dpv). Five birds from unchallenged and challenged groups were sacrificed seven days post-challenge, and blood, bursa, spleen, and cloacal swabs were collected. The IBD antibodies (Abs), lymphoid lesions, and viral load were determined. Results: The UPM1432/2019 virus induced bursal damage in vaccinated SPF chickens despite Ab titers. The mean Ab titers of the Vaccine A challenged group were significantly lower (p < 0.002) than in the unchallenged group at 28 dpv. The bursal indices of the vaccinated unchallenged groups did not differ significantly from those of the vaccinated challenged groups (p = 0.94). Microscopically, the bursae of the challenged groups showed significant atrophy. The bursal lesion score was higher (p < 0.05) in the control and Vaccine B challenged groups than the Vaccine A challenged group. The challenged group had a higher viral load than the vaccinated groups (p < 0.001). Conclusions and Relevance: Neither vaccine fully protected against a vaIBDV challenge, highlighting the limitations of current vaccines and the need for further research. [ABSTRACT FROM AUTHOR]

Newcastle disease (ND) is among the most important poultry diseases worldwide. It is the major threat to poultry production in Africa and causes major economic losses for both local and commercial chickens. To date, half of ND class II genotypes have been reported in Africa (I, IV, V, VI, VII, XI, XIII, XIV, XVII, XVIII, and XXI). The information on the circulating NDV genotypes is still scarce despite the endemic nature of ND in most countries on the African continent.A total of 659 oro-cloacal swabs were collected from local chickens in Mawenzi live bird market located in Morogoro, Tanzania, between June 2020 and May 2021. Newcastle disease virus was detected by using reverse transcription real-time polymerase chain reaction (RT-qPCR) and conventional PCR followed by sequencing of PCR products. The prevalence of NDV in the surveilled live bird markets was 23.5%. Sequencing and phylogenetic analysis revealed the presence of sub-genotype VII.2. The detected sub-genotype VII.2 has phylogenetic links to Zambian NDV strains implying a Southeast dissemination of the virus, considering that it was first detected in Mozambique. This study underscores the need of active NDV surveillance to determine the distribution of this NDV genotype in the country and monitor its spread and contribution to the emergence of new ND viruses.

Ascites syndrome (AS) in broiler chickens, also known as pulmonary arterial hypertension (PAH), is a significant disease in the poultry industry. It is a nutritional metabolic disease that is closely associated with hypoxia-inducible factors and rapid growth. The rise in pulmonary artery pressure is a crucial characteristic of AS and is instrumental in its development. Hypoxia-inducible factor 1α (HIF-1α) is an active subunit of a key transcription factor in the oxygen-sensing pathway. HIF-1α plays a vital role in oxygen homeostasis and the development of pulmonary hypertension. Studying the effects of HIF-1α on pulmonary hypertension in humans or mammals, as well as ascites in broilers, can help us understand the pathogenesis of AS. Therefore, this review aims to (1) summarize the mechanism of HIF-1α in the development of pulmonary hypertension, (2) provide theoretical significance in explaining the mechanism of HIF-1α in the development of pulmonary arterial hypertension (ascites syndrome) in broilers, and (3) establish the correlation between HIF-1α and pulmonary arterial hypertension (ascites syndrome) in broilers. HIGHLIGHTS: Explains the hypoxic mechanism of HIF-1α. Linking HIF-1α to pulmonary hypertension in broilers. Explains the role of microRNAs in pulmonary arterial hypertension in broilers. [ABSTRACT FROM AUTHOR]

Dimetridazole (DMZ) is a broad-spectrum anti-anaerobic and antiprotozoal drug extensively used for the control of blackhead disease in poultry (especially turkeys). The presence of DMZ and its metabolites in animal food poses potential risks to human health. In this study, we developed a high-performance liquid chromatography tandem mass spectrometry (HPLC/MS-MS) method for the precise detection of DMZ and its metabolite 2-hydroxymethyl-1-methyl-5-nitroimidazole (HMMNI). Our results demonstrate a strong linear relationship (r² > 0.99) between the concentrations of DMZ and HMMNI in tissues and egg within the range of 1~100 ng/g. The limits of detection (LOD) were determined to be 0.5 ng/g, with corresponding limits of quantification (LOQ) at 1.0 ng/g. Furthermore, average recoveries in tissues and egg fell within the range of 84.90% to 103.01%, with coefficients of variation below 15% for both intra-day and inter-day analyses. To investigate the residue elimination pattern of DMZ and HMMNI, diets containing 500 mg/kg DMZ were fed to healthy SanHuang chicken and Hy-line Gray laying hens for 10 consecutive days. The results indicated that the concentration of HMMNI consistently exceeded that of DMZ during the same period, in both broiler tissues and egg. Sebum showed the slowest elimination of DMZ and HMMNI, becoming undetectable after 168 h of withdrawal. In egg, residues of both substances peaked on the first day after drug withdrawal, followed by slow elimination with half-lives of 0.45 days for DMZ and 0.66 days for HMMNI. Based on these findings, WT1.4 software was used to calculate a withdrawal time of 11 days for broilers and an egg abandonment period of 14 days after withdrawal for laying hens, providing a scientific basis for the safe and rational use of DMZ in poultry farming. [ABSTRACT FROM AUTHOR]

Newcastle disease (ND), an economically important disease in poultry, is caused by virulent strains of the genetically diverse Orthoavulavirus javaense (OAVJ). Laboratories rely on quantitative real-time reverse transcription PCR (qRT-PCR) to detect OAVJ and differentiate between OAVJ pathotypes. This study demonstrates that a fusion cleavage site based molecular beacon with reverse transcription loop mediated isothermal amplification (MB-RT-LAMP) assay can detect and differentiate OAVJ pathotypes in a single assay. Data show that the assay can rapidly identify diverse OAVJ genotypes with sensitivity only one log-fold lower than the current fusion qRT-PCR assay (104 copies), exhibits a high degree of specificity for OAVJ, and the molecular beacon can differentiate mesogenic/velogenic sequences from lentogenic sequences. Further, data show that a two-minute rapid lysis protocol preceding MB-RT-LAMP can detect and differentiate OAVJ RNA from both spiked samples and oropharyngeal swabs without the need for RNA isolation. As the MB-RT-LAMP assay can rapidly detect and discriminate between lentogenic and mesogenic/velogenic sequences of OAVJ within one assay, without the need for RNA isolation, and is adaptable to existing veterinary diagnostic laboratory workflow without additional equipment, this assay could be a rapid primary screening tool before qRT-PCR based validation in resource limited settings. [ABSTRACT FROM AUTHOR]

Accurate and timely molecular diagnosis of respiratory diseases in chickens is essential for implementing effective control measures, preventing the spread of diseases within poultry flocks, minimizing economic loss, and guarding food security. Traditional molecular diagnostic methods like polymerase chain reaction (PCR) require expensive equipment and trained personnel, limiting their use to centralized labs with a significant delay between sample collection and results. Loop-mediated isothermal amplification (LAMP) of nucleic acids offers an attractive alternative for detecting respiratory viruses in broiler chickens with sensitivity comparable to that of PCR. LAMP's main advantages over PCR are its constant incubation temperature (∼65 °C), high amplification efficiency, and contaminant tolerance, which reduce equipment complexity, cost, and power consumption and enable instrument-free tests. This review highlights effective LAMP methods and variants that have been developed for detecting respiratory viruses in chickens at the point of need. [ABSTRACT FROM AUTHOR]

Marek's disease (MD) is a neoplastic disease that significantly affects the poultry industry. Long non-coding RNAs (lncRNAs) are crucial regulatory factors in various biological processes, including tumourigenesis. However, the involvement of novel lncRNAs in the course of MD virus (MDV) infection is still underexplored. Here, we present the first comprehensive characterization of differentially expressed lncRNAs in chicken spleen at different stages of MDV infection. A series of differentially expressed lncRNAs was identified at each stage of MDV infection through screening. Notably, our investigation revealed a novel lncRNA, lncRNA 803, which exhibited significant differential expression at different stages of MDV infection and was likely to be associated with the p53 pathway. Further analyses demonstrated that the overexpression of lncRNA 803 positively regulated the expression of p53 and TP53BP1 in DF-1 cells, leading to the inhibition of apoptosis. This is the first study to focus on the lncRNA expression profiles in chicken spleens during MDV pathogenesis. Our findings highlight the potential role of the p53-related novel lncRNA 803 in MD pathogenesis and provide valuable insights for decoding the molecular mechanism of MD pathogenesis involving non-coding RNA. RESEARCH HIGHLIGHTS Differentially expressed lncRNAs in spleens of chickens infected with Marek's disease virus at different stages were identified for the first time. The effects of novel lncRNA 803 on p53 pathway and apoptosis of DF-1 cells were reported for the first time. [ABSTRACT FROM AUTHOR]

Mycoplasma gallisepticum (MG) and Mycoplasma synoviae (MS) are the primary agents responsible for mycoplasma disease in poultry. MG has been identified as a significant cause of chronic respiratory disease in chickens, while MS has been linked to the development of tenosynovitis, joint swelling and other symptoms in chickens, leading to considerable economic losses for the poultry industry. Unfortunately, there is no specific drug for treatment and vaccination is the most important way to control the disease. There are some different types of vaccines, including live vaccines, inactivated vaccines, sub-unit vaccines and vector vaccines. This paper provides a comprehensive review of the development of vaccines for MG and MS. [ABSTRACT FROM AUTHOR]

Avian leukosis viruses (ALVs) include a group of avian retroviruses primarily associated with neoplastic diseases in poultry, commonly referred to as avian leukosis. Belonging to different subgroups based on their envelope properties, ALV subgroups A, B, and J (ALV-A, ALV-B, and ALV-J) are the most widespread in poultry populations. Early identification and removal of virus-shedding birds from infected flocks are essential for the ALVs' eradication. Therefore, the development of rapid, accurate, simple-to-use, and cost effective on-site diagnostic methods for the detection of ALV subgroups is very important. Cas13a, an RNA-guided RNA endonuclease that cleaves target single-stranded RNA, also exhibits non-specific endonuclease activity on any bystander RNA in close proximity. The distinct trans-cleavage activity of Cas13 has been exploited in the molecular diagnosis of multiple pathogens including several viruses. Here, we describe the development and application of a highly sensitive Cas13a-based molecular test for the specific detection of proviral DNA of ALV-A, B, and J subgroups. Prokaryotically expressed LwaCas13a, purified through ion exchange and size-exclusion chromatography, was combined with recombinase polymerase amplification (RPA) and T7 transcription to establish the SHERLOCK (specific high-sensitivity enzymatic reporter unlocking) molecular detection system for the detection of proviral DNA of ALV-A/B/J subgroups. This novel method that needs less sample input with a short turnaround time is based on isothermal detection at 37 °C with a color-based lateral flow readout. The detection limit of the assay for ALV-A/B/J subgroups was 50 copies with no cross reactivity with ALV-C/D/E subgroups and other avian oncogenic viruses such as reticuloendotheliosis virus (REV) and Marek's disease virus (MDV). The development and evaluation of a highly sensitive and specific visual method of detection of ALV-A/B/J nucleic acids using CRISPR-Cas13a described here will help in ALV detection in eradication programs. [ABSTRACT FROM AUTHOR]

Dr. Benjamin S. Pomeroy was a highly respected veterinarian who specialized in poultry production and the control of poultry diseases. He obtained his veterinary degree from Iowa State University and went on to earn a Master of Science and a PhD from Cornell University and the University of Minnesota, respectively. Dr. Pomeroy's research focused on poultry diseases, particularly salmonellosis, and he played a significant role in the development of disease control programs. He also contributed to the establishment of veterinary specialization in avian pathology and was involved in the founding of important professional organizations. Dr. Pomeroy's expertise and contributions to the field of veterinary medicine were widely recognized and he continues to inspire others in the field. [Extracted from the article]

Live coccidiosis vaccines have mainly been used to reduce Eimeria species infection, which is considered the most economically important disease in the poultry industry. Evaluation data on vaccine effectiveness through large-scale field experiments are lacking, especially in broilers. Thus, the effectiveness of a commercial coccidiosis vaccine was evaluated in approximately 900,000 chicks reared on three open-broiler farms where coccidiosis is prevalent. The vaccine's effectiveness after vaccination of 1-day-old chicks was monitored using three parameters (lesion score, fecal oocyst shedding, and production index, PI) in nine trials performed three times on each farm. Lesion scores were confirmed in three different areas of the intestine because the vaccine contained four Eimeria species. The average lesion scores were 0.36 to 0.64 in the duodenal region, 0.30 to 0.39 in the jejuno-ileal region, and 0.18 to 0.39 in the cecal region. The average fecal oocyst shedding rate ranged from 19,766 to 100,100 oocysts per gram, showing large variations depending on farms and buildings within the farm. Compared with the PI of the previous 9–10 trials on each farm, the PI increased by 2.45 to 23.55. Because of the potential for perturbation of the fecal microbiota by live coccidiosis vaccines, the fecal microbiota was investigated using 16S rRNA microbial profiling. Although the β-diversity was significantly different in distribution and relative abundance among farms (PERMANOVA, pseudo-F = 4.863, p = 0.009), a Kyoto Encyclopedia of Genes and Genomes pathway analysis found no significant bacterial invasion of the epithelial cell pathway across farms. This large-scale field trial of a live Eimeria vaccine indicates that coccidiosis vaccines can have meaningful effects on the poultry industry and could be used as an alternative to the prophylactic use of anticoccidial drugs under field conditions. [ABSTRACT FROM AUTHOR]

Infectious bursal disease (IBD) is one of the dangerous diseases of poultry that affects the bursa of Fabricius, which is an important organ of the bird’s immune system. IBD virus is resistant to many drugs, making its control difficult. Vaccination of IBD is in practice for a long time worldwide to control IBD, but secondary issues like vaccine failure and lower efficacy lead to their reduced use in the field. Multiple medicines are currently used, but the phytochemicals have emerged as promising agents for controlling IBD. The drugs to be developed should possess direct antiviral properties by targeting viral entry mechanisms, enhancing the host immune response, and inhibiting viral protein synthesis. Phytochemicals have potential to contribute to food security by minimizing the possibility of disease outbreaks and ensuring that consumers worldwide obtain healthy poultry products. It has been now claimed that direct and indirect activities of phytochemicals can be effective in the control of IBDV. Although available evidence suggest that the phytochemicals can contribute in controlling occurrence IBDV, there is a definite need of focused studies to gain more insight and develop rational strategies for their practical use. This review highlights the disease caused by IBDV, inhibition of viral replication, boosting the immune system, disruption of viral membrane, and important phytochemicals showing antiviral activities against IBDV. [ABSTRACT FROM AUTHOR]

Campylobacter is a leading cause of food-borne gastroenteritis worldwide, linked to the consumption of contaminated poultry meat. Targeting this pathogen at source, vaccines for poultry can provide short-term caecal reductions in Campylobacter numbers in the chicken intestine. However, this approach is unlikely to reduce Campylobacter in the food chain or human incidence. This is likely as vaccines typically target only a subset of the high genomic strain diversity circulating among chicken flocks, and rapid evolution diminishes vaccine efficacy over time. To address this, we used a genomic approach to develop a whole-cell autogenous vaccine targeting isolates harbouring genes linked to survival outside of the host. We hyper-immunised a whole major UK breeder farm to passively target offspring colonisation using maternally-derived antibody. Monitoring progeny, broiler flocks revealed a near-complete shift in the post-vaccination Campylobacter population with an ~50% reduction in isolates harbouring extra-intestinal survival genes and a significant reduction of Campylobacter cells surviving on the surface of meat. Based on these findings, we developed a logistic regression model that predicted that vaccine efficacy could be extended to target 65% of a population of clinically relevant strains. Immuno-manipulation of poultry microbiomes towards less harmful commensal isolates by competitive exclusion, has major potential for reducing pathogens in the food production chain. [ABSTRACT FROM AUTHOR]

Multiparameter flow cytometry is a routine method in immunological studies incorporated in biomedical, veterinary, agricultural, and wildlife research and routinely used in veterinary clinical laboratories. Its use in the diagnostics of poultry diseases is still limited, but due to the continuous expansion of reagents and cost reductions, this may change in the near future. Although the structure and function of the avian immune system show commonalities with mammals, at the molecular level, there is often low homology across species. The cross-reactivity of mammalian immunological reagents is therefore low, but nevertheless, the list of reagents to study chicken immune cells is increasing. Recent improvement in multicolor antibody panels for chicken cells has resulted in more detailed analysis by flow cytometry and has allowed the discovery of novel leukocyte cell subpopulations. In this article, we present an overview of the reagents and guidance needed to perform multicolor flow cytometry using chicken samples and common pitfalls to avoid. [ABSTRACT FROM AUTHOR]

Avian coccidiosis, a parasitic disease prevalent in poultry, is caused by Eimeria species and leads to significant economic losses. The use of attenuated live oocyst vaccines has been adopted as an alternative to the use of anticoccidial drugs. However, the accurate detection and differentiation of vaccine strains from virulent ones remain challenging. Therefore, this study presents a novel TaqMan polymerase chain reaction (PCR) detection method that offers enhanced sensitivity, specificity, and reproducibility compared with traditional PCR techniques. Through whole-genome resequencing and bioinformatics analysis, we identified a molecular marker gene, Em_marker6, with a unique 21-base pair deletion specific to the Eimeria maxima attenuated vaccine strain. Optimized primers and probes targeting this marker enabled rapid quantification cycle value achievement and high fluorescence intensity. The standard curve's slope of -3.540 and correlation coefficient of 0.9971 confirmed precise quantification capabilities. The TaqMan PCR method detected as few as 30 plasmid DNA copies and 50 oocysts per reaction, outperforming traditional PCR techniques by an order of magnitude. No cross-reactivity was observed with other E. maxima wide-type strains or common intestinal pathogens, ensuring the exclusive detection of the E. maxima EMPY vaccine strain. Weekly testing over 3 weeks demonstrated minimal variability, indicating robust consistency in the method's application. Testing on 61 clinical samples revealed a 57.38% positivity rate for E. maxima species and 13.11% for the vaccine strain. The Em_marker6 gene exhibited genetic stability across multiple generations, confirming the detection method's robust stability for the attenuated E. maxima vaccine strain. This study significantly advances the field of avian coccidiosis research and control by providing a valuable tool for monitoring vaccine purity and preventing inadvertent infections in vaccinated flocks, aligning with global efforts to curb antibiotic use in animal feed. [ABSTRACT FROM AUTHOR]

Simple Summary: Simple Summary: The prevention of the spread of poultry diseases within and among farms largely depends on the adoption of good biosecurity practices. Through the process of profiling European poultry producers, we were able to identify the particular aspects that influence the adoption of biosecurity practices. The results suggest a wide and varied attitude towards biosecurity in the poultry farming community. Generally, most producers appear to be aware of the risks associated with poor biosecurity and the outcomes of carrying out or not carrying out certain practices. Yet, compared with producers of laying hens or parent breeding stock, meat poultry producers (broiler, turkeys, and ducks) appear to have more blocking components with regard to biosecurity. The education level had a positive effect on perception about biosecurity. Poultry producers are not a homogeneous group, and to change their attitudes and actions, approaches must consider the producers' mindset and need to be tailored to the specific needs of the producers. Poultry producers' attitudes towards biosecurity practices were assessed by using the ADKAR® (Awareness, Desire, Knowledge, Ability, and Reinforcement) behavioral change model. Conventional poultry producers (n = 155) from different production types including broilers (n = 35), layers (n = 22), breeders (n = 24), turkeys (n = 19), ducks (n = 23), free-range broilers (n = 11), free-range layers (n = 11), and hatcheries (n = 10) from seven European countries were scored for each ADKAR element (1 = total absence to 5 = perfect fulfilment). Each country performed selected interventions (e.g., coaching, participatory meetings, etc.) to improve biosecurity compliance. After the interventions, significant change was observed in three of the four attitude elements. The overall mean scores ( x ¯ ± SD) obtained during the initial assessment (n = 130) were 4.2 ± 0.6 for Awareness, 4.1 ± 0.7 for Desire, 3.8 ± 0.8 for Knowledge, and 4.0 ± 0.7 for Ability, whereas after intervention, the scores were A = 4.3 ± 0.6, D = 4.2 ± 0.7, K = 4.1 ± 0.7, and Ab = 4.1 ± 0.7. The Reinforcement component was only evaluated after the change and obtained a score of 3.7 ± 0.7 on average. Identifying the elements influencing poultry producers and their behavior related to farm management decisions was useful in guiding our educational interventions to effectively change their behavior. [ABSTRACT FROM AUTHOR]

Simple Summary: Necrotic enteritis caused by Clostridium perfringens (CP) is an important disease for the poultry industry. It leads to decreased growth and production performance in chickens. Bacillus amyloliquefaciens SC06 (BaSC06) is known to play a role in preventing damage from the bacterial infection. However, whether CP could affect brain function and behavior and whether BaSC06 has a preventive role in infected animals are not yet reported. Thus, the aim of this study was to investigate whether BaSC06 has a preventative effect on broiler chickens infected by CP. Our results showed that CP is associated with a reduction in stress and fear-related behaviors and causes pathological damage to the pia and cortex of the brain, as well as inhibiting the expression of genes related to stress, while the treatment of BaSC06 alleviates these adverse effects. Poultry studies conducted on Clostridium perfringens (CP) mainly focus on the effects of intestinal health and productive performance. Notably, the probiotic Bacillus amyloliquefaciens SC06 (BaSC06) is known to play a role in preventing bacterial infection. However, whether CP could induce the changes in brain function and behaviors and whether BaSC06 could play roles in these parameters is yet to be reported. The aim of this study was to evaluate the effects of BaSC06 on stress-related behaviors and gene expression, as well as the brain morphology and mRNA sequence of the hypothalamus in broiler chickens. A total of 288 one-day-old chicks were randomly divided into four groups: (1) a control group with no treatment administered or infection; (2) birds treated with the BaSC06 group; (3) a CP group; and (4) a BaSC06 plus CP (Ba_CP) group. The results showed that stress and fear-related behaviors were significantly induced by a CP infection and decreased due to the treatment of BaSC06. CP infection caused pathological damage to the pia and cortex of the brain, while BaSC06 showed a protective effect. CP significantly inhibited hypothalamic GABA and promoted HTR1A gene expression, while BaSC06 promoted GABA and decreased HTR1A gene expression. The different genes were nearly found between the comparisons of control vs. Ba group and Ba vs. CP group, while there were a great number of different genes between the comparisons of control vs. Ba_CP as well as CP vs. Ba_CP. Several different gene expression pathways were found that were related to disease, energy metabolism, and nervous system development. Our results will help to promote poultry welfare and health, as well as provide insights into probiotics to replace antibiotics and reduce resistance in the chicken industry. [ABSTRACT FROM AUTHOR]

SUMMARY Infectious laryngotracheitis (ILT) is a very serious worldwide respiratory disease of poultry, with many countries reporting ILT infections over the last decade. However, few reports are available regarding ILT disease prevalence in poultry in Turkey. Accordingly, the present study investigated ILT infection in Turkish broiler flocks between 2018 and 2022. Circulating ILT strains were characterized by sequence and phylogenetic analysis of two fragments of the infected-cell protein 4 gene. ILT virus (ILTV) was confirmed by quantitative PCR in 8 of the 21 flocks examined. As in other diseases, co-infections with other respiratory pathogens in confirmed ILT cases may worsen the symptoms and prolong the disease course. The present study confirmed co-infections with infectious bronchitis virus (13/21 tested flocks and 5/8 ILTV-positive flocks), indicating the importance of these pathogens in the occurrence of ILT infections. RESUMEN Circulación y caracterización molecular del virus de la laringotraqueítis infecciosa en bandadas de aves de corral con trastornos respiratorios en Turquía, 2018–2022. La laringotraqueítis infecciosa (ILT) es una enfermedad respiratoria muy seria de la industria avícola en todo el mundo y muchos países han notificado infecciones por esta enfermedad durante la última década. Sin embargo, hay pocos informes disponibles sobre la prevalencia de laringotraqueítis infecciosa en la avicultura de Turquía. En consecuencia, el presente estudio investigó la infección por laringotraqueítis infecciosa en parvadas de pollos de engorde en Turquía entre los años 2018 y 2022. Las cepas de laringotraqueítis infecciosa circulantes se caracterizaron mediante análisis de secuencias y filogenéticos de dos fragmentos del gene de la proteína 4 de las células infectadas. El virus ILT (ILTV) se confirmó mediante PCR cuantitativa en ocho de las 21 parvadas examinadas. Como ocurre con otras enfermedades, las coinfecciones con otros patógenos respiratorios en casos confirmados de laringotraqueítis infecciosa pueden complicar los signos clínicos y prolongar el curso de la enfermedad. El presente estudio confirmó coinfecciones con el virus de la bronquitis infecciosa (en 13/21 parvadas analizadas y en 5/8 parvadas positivas para laringotraqueítis infecciosa), lo que indica la importancia de estos patógenos en la aparición de infecciones por la laringotraqueítis infecciosa. [ABSTRACT FROM AUTHOR]

Newcastle disease (ND) is a significant infectious disease in poultry, causing substantial economic losses in developing countries. To control ND, chickens must be vaccinated multiple times a year. In order to develop an improved vaccine that provides long-term protection, the F gene from genotype VII NDV was inserted into the herpesvirus of turkey (HVT) vaccine virus using CRISPR/Cas9-mediated NHEJ repair and Cre/LoxP technology. The immunogenicity and protective efficacy of the resulting recombinant vaccines were evaluated through antibody assays and virus challenge experiments. Two recombinant vaccines, rHVT-005/006-F and rHVT-US2-F, were generated, both exhibiting growth rates comparable with those of HVT in vitro and consistently expressing the F protein. One-day-old specific pathogen-free (SPF) chickens immunized with 2000 PFU/bird of either rHVT-005/006-F or rHVT-US2-F developed robust humoral immunity and were completely protected against challenge with the NDV F48E8 strain at 4 weeks post-vaccination (wpv). Furthermore, a single dose of these vaccines provided sustained protection for at least 52 wpv. Our study identifies rHVT-005/006-F and rHVT-US2-F as promising ND vaccine candidates, offering long-term protection with a single administration. Moreover, HVT-005/006 demonstrates promise for accommodating additional foreign genes, facilitating the construction of multiplex vaccines. [ABSTRACT FROM AUTHOR]

The article discusses the avian influenza A (H7N5) outbreak, emphasizing the importance of monitoring less common subtypes like H7N5 due to their potential to mutate into highly pathogenic strains. While H7N5 is not widely known compared to other subtypes, a recent outbreak in Germany highlights the need for continuous surveillance and research to prevent major outbreaks. The genetic potential of viruses like H7N5 underscores the necessity of robust surveillance, research, and preparedness strategies to mitigate their impact and prevent widespread disease outbreaks. The establishment of an epidemiological monitoring group is crucial to stay ahead of potential new outbreaks and ensure effective management. [Extracted from the article]

The document titled "Cover Advertisements" provides information about Dr. Stanley H. Kleven, a highly respected researcher in the field of avian diseases. Dr. Kleven's research focused on avian mycoplasmosis and he made significant contributions to understanding the diversity between strains and species of avian Mycoplasma. The document also includes information about the journal Avian Diseases, which publishes original observations on avian diseases and is widely circulated among decision-makers in the field. Additionally, the document provides information about advertising rates and formats for the journal. [Extracted from the article]

Four turkeys from a commercial flock with acutely elevated mortality levels were submitted for postmortem examination and diagnostic workup. No clinical signs had been observed before death. On gross examination, hemorrhage and necrosis were present throughout the intestinal tracts, and the spleens were markedly enlarged and speckled. Microscopically, numerous, large basophilic-to-amphophilic intranuclear inclusion bodies were observed in mononuclear cells of the spleen and the lamina propria of the small intestine. In addition, there were lesions of diffuse villus blunting and necrosis of the small intestine, with large numbers of rod-shaped bacteria adhered to the epithelium and in the intestinal lumen. Hemorrhagic enteritis virus (HEV) infection was confirmed via PCR on the spleen. Clostridium perfringens was demonstrated in the small intestine by anaerobic culture and immunohistochemistry. The C. perfringens isolate was type F by PCR and, to our knowledge, necrotic enteritis in turkeys has not been described in association with C. perfringens type F infection.

Chicks are ideal to follow the development of the intestinal microbiota and to understand how a pathogen perturbs this developing population. Taxonomic/metagenomic analyses captured the development of the chick microbiota in unperturbed chicks and in chicks infected with Salmonella enterica serotype Typhimurium (STm) during development. Taxonomic analysis suggests that colonization by the chicken microbiota takes place in several waves. The cecal microbiota stabilizes at day 12 posthatch with prominent Gammaproteobacteria and Clostridiales. Introduction of S. Typhimurium at day 4 posthatch disrupted the expected waves of intestinal colonization. Taxonomic and metagenomic shotgun sequencing analyses allowed us to identify species present in uninfected chicks. Untargeted metabolomics suggested different metabolic activities in infected chick microbiota. This analysis and gas chromatography-mass spectrometry on ingesta confirmed that lactic acid in cecal content coincides with the stable presence of enterococci in STm-infected chicks. Unique metabolites, including 2-isopropylmalic acid, an intermediate in the biosynthesis of leucine, were present only in the cecal content of STm-infected chicks. The metagenomic data suggested that the microbiota in STm-infected chicks contained a higher abundance of genes, from STm itself, involved in branched-chain amino acid synthesis. We generated an ilvC deletion mutant (STM3909) encoding ketol-acid-reductoisomerase, a gene required for the production of l-isoleucine and l-valine. ΔilvC mutants are disadvantaged for growth during competitive infection with the wild type. Providing the ilvC gene in trans restored the growth of the ΔilvC mutant. Our integrative approach identified biochemical pathways used by STm to establish a colonization niche in the chick intestine during development. IMPORTANCE Chicks are an ideal model to follow the development of the intestinal microbiota and to understand how a pathogen perturbs this developing population. Using taxonomic and metagenomic analyses, we captured the development of chick microbiota to 19 days posthatch in unperturbed chicks and in chicks infected with Salmonella enterica serotype Typhimurium (STm). We show that normal development of the microbiota takes place in waves and is altered in the presence of a pathogen. Metagenomics and metabolomics suggested that branched-chain amino acid biosynthesis is especially important for Salmonella growth in the infected chick intestine. Salmonella mutants unable to make l-isoleucine and l-valine colonize the chick intestine poorly. Restoration of the pathway for biosynthesis of these amino acids restored the colonizing ability of Salmonella. Integration of multiple analyses allowed us to correctly identify biochemical pathways used by Salmonella to establish a niche for colonization in the chick intestine during development.

Recently, herpesvirus of turkeys (HVT), which was initially employed as a vaccine against Marek's disease (MD), has been shown to be a highly effective viral vector for producing recombinant vaccines that can simultaneously express the protective antigens of multiple poultry diseases. Prior to the development of commercial HVT-vectored dual-insert vaccines, the majority of HVT-vectored vaccines in use only contained a single foreign gene and were often generated using time-consuming and inefficient traditional recombination methods. The development of multivalent HVT-vectored vaccines that induce simultaneous protection against several avian diseases is of great value. In particular, efficacy interference between individual recombinant HVT vaccines can be avoided. Herein, we demonstrated the use of CRISPR/Cas9 gene editing technology for the insertion of an IBDV (G2d) VP2 expression cassette into the UL45/46 region of the recombinant rHVT-HA viral genome to generate the dual insert rHVTVP2- HA recombinant vaccine. The efficacy of this recombinant virus was also evaluated in specific pathogen-free (SPF) chickens. PCR and sequencing results showed that the recombinant virus rHVT-VP2-HA was successfully constructed. Vaccination with rHVT-VP2-HA produced high levels of specific antibodies against IBDV (G2d) and H9N2/Y280. rHVT-VP2-HA can provide 100% protection against challenges with IBDV (G2d) and H9N2/Y280. These results demonstrate that rHVT-VP2-HA is a safe and highly efficacious vaccine for the simultaneous control of IBDV (G2d) and H9N2/Y280. [ABSTRACT FROM AUTHOR]

Gumboro disease is a viral poultry disease that causes immune suppression on the infected birds leading to poor production, mortality, and exposure to secondary infections, hence a major threat in the poultry industry worldwide. A mathematical model of the transmission dynamics of Gumboro disease is developed in this paper having four compartments of chicken population and one compartment of Gumboro pathogen population. The basic reproduction number R og is derived, and the dynamical behaviors of both the disease-free equilibrium (DFE) and endemic equilibrium are analyzed using the ordinary differential equation theory. From the analysis, we found that the system exhibits an asymptotic stable DFE whenever R og < 1 and an asymptotic stable EE whenever R og > 1. The numerical simulation to verify the theoretical results was carried out using MATLAB ode45 solver, and the results were found to be consistent with the theoretical findings. [ABSTRACT FROM AUTHOR]

The botanical insecticide market is growing because of limitations placed on the use of certain synthetic chemical insecticides. In this sense, the lesser mealworm Alphitobius diaperius (Coleoptera: Tenebrionidae) is the main poultry pest. The insect causes weight loss and damage to the digestive system of poultry, and it is a vector and reservoir of pathogens. Consequently, this study explored the following hypotheses: (i) essential oils (EOs) derived from Mentha spp. are toxic to A. diaperius; (ii) these EOs are compatible with Beauveria bassiana, the natural enemy of the poultry pest, that parasite A. diaperinus; (iii) these EOs also exhibit activity against bacteria that are pathogenic to poultry. In topical applications and ingestion tests, EOs from Mentha arvensis, Mentha spicata, and Mentha piperita were toxic to A. diaperinus. Chromatographic analyses revealed that menthol is the predominant compound in M. arvensis and M. piperita, whereas carvone is the major compound in M. spicata. Both (−)- and (+)-menthol, along with (−)- and (+)-carvone, underwent testing with A. diaperinus. Nevertheless, their activity was not as potent as those of the EOs, suggesting a possible synergistic and/or additive effect. The EOs did not have any adverse effects on the conidial germination, vegetative growth, or conidia production per colony of the entomopathogenic fungus B. bassiana. Consequently, these EOs are compatible with this natural enemy. The EO extracted from M. spicata exhibited significant toxicity against Staphylococcus aureus (ATCC 25923), whereas the remaining EOs displayed moderate toxicity against this bacterium. The EOs derived from Mentha spp., as assessed in this study, hold promise for the development of botanical insecticides tailored for the control of A. diaperinus. These insecticides are selective in favor of the natural enemy B. bassiana and can also serve as effective sanitizers, thanks to their antibacterial properties. [ABSTRACT FROM AUTHOR]

An accurate understanding of the ecology and complexity of the poultry respiratory microbiota is of utmost importance for elucidating the roles of commensal or pathogenic microorganisms in the respiratory tract, as well as their associations with health or disease outcomes in poultry. This comprehensive review delves into the intricate aspects of the poultry respiratory microbiota, focusing on its colonization patterns, composition, and impact on poultry health. Firstly, an updated overview of the current knowledge concerning the composition of the microbiota in the respiratory tract of poultry is provided, as well as the factors that influence the dynamics of community structure and diversity. Additionally, the significant role that the poultry respiratory microbiota plays in economically relevant respiratory pathobiologies that affect poultry is explored. In addition, the challenges encountered when studying the poultry respiratory microbiota are addressed, including the dynamic nature of microbial communities, site-specific variations, the need for standardized protocols, the appropriate sequencing technologies, and the limitations associated with sampling methodology. Furthermore, emerging evidence that suggests bidirectional communication between the gut and respiratory microbiota in poultry is described, where disturbances in one microbiota can impact the other. Understanding this intricate cross talk holds the potential to provide valuable insights for enhancing poultry health and disease control. It becomes evident that gaining a comprehensive understanding of the multifaceted roles of the poultry respiratory microbiota, as presented in this review, is crucial for optimizing poultry health management and improving overall outcomes in poultry production. [ABSTRACT FROM AUTHOR]

The primary natural reservoir of the H5N1 avian influenza virus is poultry and wild birds, particularly waterfowl. Nevertheless, the H5N1 virus subtype can potentially infect humans and other mammals, causing severe illness or even death. The virus is commonly transmitted through direct contact with infected birds or exposure to a contaminated environment. Sporadic cases of avian influenza subtype H5 have been reported in various new hosts, such as minks, otters, foxes, and sea lions, with the potential to cause human infection and trigger a global pandemic. Moreover, various hosts have the potential to act as mixing vessels for influenza viruses because they carry both avian and human-type receptors, not just pigs. Recently, highly pathogenic avian influenza H5 was reported in farmed animals such as dairy cattle, suggesting a new potential mixing vessel for influenza; thus, cattle are also widely infected with the genus influenza type D viruses. This underscores the imperative to adopt the One Health approach, fostering collaboration and integration across animal, planetary, and human health disciplines. Indeed, integrating biosecurity and One Health principles impacts the productivity of commercial poultry operations positively and could help mitigate avian influenza outbreaks. This review also provides an in-depth analysis of the contemporary and molecular epidemiology of H5N1 influenza viruses. Moreover, our examination delves into the potential risk of broadening H5N1 host tropism and its significant relevance within the One Health framework. [ABSTRACT FROM AUTHOR]

Newcastle disease (ND) is among the most common and deadliest poultry diseases worldwide. Thermostable Newcastle disease virus (NDV) vaccines have been widely used to protect village chickens against ND due to their decreased dependence on cold chains for transport and storage. The NDV4 Heat-Resistant (NDV4HR) vaccine is an apathogenic, heat-resistant, live vaccine that can induce immunity in chickens. In this study, 60 one-day-old Arain local hybrid broilers were divided into three groups of 20. Group A had the usual vaccination program in broiler flocks (seven days old: B1 type by eye drop and ND killed vaccine intramuscularly; 18 and 28 days old: LaSota strain orally). Group B did not receive any vaccine, and group C received the NDV4HR vaccine orally, six times from the first day to the 35th day of rearing. All groups were nasally challenged with acute Newcastle virus (genotype VIId) on the 35th rearing day. Regarding the hemagglutination inhibition serum antibody titer of the birds after the challenge, group B had the highest (7.12±1.05), and group C (6.37±1.31) had a higher titer than group A (6±1.22). After the challenge with the Newcastle virus, the necropsy findings and clinical symptoms of the disease were almost similar in groups A and C. Group B showed the most signs, with higher casualties than other groups. Regarding weight gain, group C had the highest weight at the end of the study (2204±106). On the second day after the challenge, groups A and B had virus shedding through the trachea and cloaca, while group B shed the virus only through the trachea. Furthermore, on the seventh day after the challenge, group A shed the virus through the cloaca, whereas group B did it through the trachea and the cloaca. On the other hand, there was no virus shedding in group C. This study showed that the NDV4HR vaccine provokes an antibody response that protects the birds against a virulent virus challenge. [ABSTRACT FROM AUTHOR]

Each year, millions of poultry succumb to highly pathogenic avian influenza A virus (AIV) and infectious bursal disease virus (IBDV) infections. Conventional vaccines based on inactivated or live-attenuated viruses are useful tools for disease prevention and control, yet, they often fall short in terms of safety, efficacy, and development times. Therefore, versatile vaccine platforms are crucial to protect poultry from emerging viral pathogens. Self-amplifying (replicon) RNA vaccines offer a well-defined and scalable option for the protection of both animals and humans. The best-studied replicon platform, based on the Venezuelan equine encephalitis virus (VEEV; family Togaviridae) TC-83 vaccine strain, however, displays limited efficacy in poultry, warranting the exploration of alternative, avian-adapted, replicon platforms. In this study, we engineered two Tembusu virus (TMUV; family Flaviviridae) replicons encoding varying capsid gene lengths and compared these to the benchmark VEEV replicon in vitro. The TMUV replicon system exhibited a robust and prolonged transgene expression compared to the VEEV replicon system in both avian and mammalian cells. Moreover, the TMUV replicon induced a lesser cytopathic effect compared to the VEEV replicon RNA in vitro. DNA-launched versions of the TMUV and VEEV replicons (DREP) were also developed. The replicons successfully expressed the AIV haemagglutinin (HA) glycoproteins and the IBDV capsid protein (pVP2). To assess the immune responses elicited by the TMUV replicon system in chickens, a prime-boost vaccination trial was conducted using lipid nanoparticle (LNP)-formulated replicon RNA and DREP encoding the viral (glyco)proteins of AIV or IBDV. Both TMUV and VEEV replicon RNAs were unable to induce a humoral response against AIV. However, TMUV replicon RNA induced IBDV-specific seroconversion in vaccinated chickens, in contrast to VEEV replicon RNA, which showed no significant humoral response. In both AIV and IBDV immunization studies, VEEV DREP generated the highest (neutralizing) antibody responses, which underscores the potential for self-amplifying mRNA vaccine technology to combat emerging poultry diseases. [ABSTRACT FROM AUTHOR]

Background and Objectives: Antibiotic resistance within the poultry sector presents a considerable health concern due to treatment inefficacy and resistance transmission to humans and the environment. The investigation of plasmid-mediated quinolone resistance (PMQR) in Escherichia coli, acknowledged for its role in advancing resistance, remains inadequately studied in Iranian poultry. This study aimed to evaluate PMQR gene prevalence as well as to determine correlation between resistance phenotype and genotype in E. coli obtained from poultry colibacillosis. Materials and Methods: A collection of 100 E. coli isolates from the viscera of broilers suspected to colibacillosis was assessed. Using the Kirby-Bauer disk diffusion method, antimicrobial susceptibility tests were conducted for ofloxacin, nalidixic acid, levofloxacin, ciprofloxacin, and ampicillin. Additionally, PCR was employed to screen for qnrS, qnrB, and aac(6)Ib-cr genes. Results: Among the analyzed E. coli isolates, 51% demonstrated resistance to at least one of the tested antibiotics, with 17% exhibiting resistance to four different antibiotics. Nalidixic acid displayed the highest resistance rate at 48%, while ampicillin had the lowest at 16%. PMQR genes were detected in 28% of the E. coli isolates, with aac(6')-Ib-cr being the most prevalent at 14%, followed by qnrB in 13%, and qnrS in 7%. Conclusion: The study underscores the vital need for careful antibiotic usage in poultry to curb the emergence of antibiotic-resistant bacteria. The results illuminate the prevalence of PMQR genes and their association with resistance trends in Iranian poultry, forming a pivotal basis for forthcoming approaches to combat antibiotic resistance within the poultry sector. [ABSTRACT FROM AUTHOR]

Introduction Today, the businesses of the poultry industry are facing many challenges, because this industry has to manage a number of unique processes, methods and risks at the same time. Therefore, identifying the business risks of poultry production units can play an effective role in reducing the level of vulnerability of these businesses. Considering the need to increase the productivity of the poultry industry, one of the basic solutions is to identify the risk and measure the existing risks of this industry. Risk identification and quantification can reduce costs for industry stakeholders, and risk reduction leads to better production planning. In this regard, this study identifies the business risks of poultry production units in Khorasan Razavi province. Materials and Methods This study is applied as purpose and descriptive survey in terms of nature and method. This research is based on mixed research, qualitatively and quantitatively. The statistical population is poultry industry experts, 18 of whom were investigated by snowball sampling method as the research sample. This study proposes a new Delphi technique that uses the features of traditional Delphi techniques and the Fuzzy Delphi method. The proposed new Delphi technique is based on the integration of pentagonal fuzzy sets and the Delphi technique. Results and Discussion The results of the modified pentagonal Fuzzy Delphi method showed that five main risks and 36 secondary risks out of 58 identified risks are part of the business risks of poultry production units. Identified business risks of poultry production units, in order of priority, include inputs price fluctuations, command pricing, exchange rate fluctuations, sanctions, chicken price fluctuations, delay in accessing inputs, fluctuations in the purchase price of day-old chickens, fluctuations in drug and vaccine prices, imported inputs, lack of government support in the matter of production, fluctuations in subsidies to inputs, lack of animal inputs, import of poultry products, Promulgation of various instructions, poultry diseases, lack of liquidity of poultry farmers, bankruptcy of poultry farmers, fluctuations in current costs, losses, lack of medicine and vaccines, lack of expansion of poultry business, lack of confidence of poultry farmers in the government, fluctuations in profitability, investment, seasonal fluctuations in egg demand, dependence of poultry farmers on Special suppliers, supply of day-old chicks, lack of energy, exclusivity of the livestock and poultry feed supply system, egg price fluctuations, seasonal fluctuations in chicken production, seasonal fluctuations in chicken demand, weakness in providing working capital facilities to poultry farmers, lack of skilled human resources in time Appropriate, lack of technical knowledge of advanced technologies and lack of variety of poultry food ingredients. Conclusion The business of poultry production units is facing various challenges and risks, and due to the many risks of this industry, production in this industry is facing problems and it is not possible to plan for it, and production will be disrupted in the future. Therefore, in this research, an effort was made to fully identify the business risks of poultry production units. In order to complete and finalize the business risks of poultry production units, the pentagonal Fuzzy Delphi method was used. In this regard, a questionnaire was prepared that included two parts. The first part is about the survey and information about the background of the respondents, and the second part includes the ranking of 54 identified risks. Fuzzy Delphi method in this study was done in two rounds and based on the opinion of experts, 4 more risks were added to the total of 54 risks, and finally 58 risks were analyzed using Fuzzy Delphi method. In Fuzzy Delphi, the selection of risk components among all the components that were identified in the research literature was based on the accepted threshold criterion. The results of the second round of modified pentagonal Fuzzy Delphi showed that there are 36 important sub-risks in the sector of production, market, financial, institutional and personal business risks of poultry production units. Considering the price fluctuations of livestock inputs and exchange rate fluctuations, it is suggested to allocate currency and control it by government policies in order to reduce mentioned fluctuations, or move towards diversifying poultry feed ingredients and formulating new poultry feed rations. Also, in order to avoid fluctuations in the price of chicken or eggs, it is suggested to make the distribution network smarter to prevent these fluctuations. In the poultry market, it is better to set a fair price for each kilogram of chicken according to the production costs of poultry farmers, or not to interfere with the government in the market and allow the government to set the price based on the supply and demand mechanism. [ABSTRACT FROM AUTHOR]

Mycoplasma gallisepticum is one of the smallest self-replicating organisms. It causes chronic respiratory disease, leading to significant economic losses in poultry industry. Following M. gallisepticum invasion, the pathogen can persist in the host owing to its immune evasion, resulting in long-term chronic infection. The strategies of immune evasion by mycoplasmas are very complex and recent research has unraveled these sophisticated mechanisms. The antigens of M. gallisepticum exhibit high-frequency changes in size and expression cycle, allowing them to evade the activation of the host humoral immune response. M. gallisepticum can invade non-phagocytic chicken cells and also regulate microRNAs to modulate cell proliferation, inflammation, and apoptosis in tracheal epithelial cells during the disease process. M. gallisepticum has been shown to transiently activate the inflammatory response and then inhibit it by suppressing key inflammatory mediators, avoiding being cleared. The regulation and activation of immune cells are important for host response against mycoplasma infection. However, M. gallisepticum has been shown to interfere with the functions of macrophages and lymphocytes, compromising their defense capabilities. In addition, the pathogen can cause immunological damage to organs by inducing an inflammatory response, cell apoptosis, and oxidative stress, leading to immunosuppression in the host. This review comprehensively summarizes these evasion tactics employed by M. gallisepticum, providing valuable insights into better prevention and control of mycoplasma infection. [ABSTRACT FROM AUTHOR]

Marek's Disease (MD) is an economically important disease of poultry caused by the MD virus, a member of the genus Mardivirus. MD results in immunosuppression and the disease affects poultry of all ages and is characterized by neoplastic lesions in the visceral organs. In this report, the prevalence and epidemiological features of MD in Plateau State were determined. Records of poultry disease cases presented to selected veterinary clinics in 4 Local Government Areas of Plateau State from 2007 to 2016 were analyzed. In addition, data were collected using questionnaires administered to 160 poultry farmers from February to May 2017. The prevalence of MD in Plateau State was 10.92% (5,620/5,1484). Cases of MD were reported in layers (92.49%), broilers (6.98%), turkeys (0.32%), and geese (0.21%). Also, co-morbidity of MD with coccidiosis (2.24%), colibacillosis (3.26%), Newcastle disease (2.58%), fatty liver syndrome (0.36%), fowl typhoid (2.86), and chronic respiratory disease (0.34%) were documented in the records. Analyzed data from the questionnaire survey revealed that 90.63% (145/160) of poultry farmers in Plateau State were familiar with MD, and 16.88% (27/160) of farmers indicated they have experienced MD outbreaks in their farms. Additionally, 90.00% (144/160) of poultry farmers claimed their birds were vaccinated against MD of which 53.13% (85/160) have vaccinated their birds once, while 36. 25% (58/160) and 0.63% (1/160) vaccinated their birds against MD twice and thrice respectively. On the economic impact of MD, twenty-seven poultry farms had experienced MD with an overall mortality of 17.02% (12,114/71,176) and most of the affected farms claimed to frequently medicate their birds during the outbreaks. To mitigate the impact of MD on poultry in Plateau State, adequate biosecurity measures and vaccination need to be instituted in poultry farms. [ABSTRACT FROM AUTHOR]