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Infectious bronchitis virus (IBV) is among the most impactful poultry pathogens, whose control, based on biosecurity and routine vaccination, is hampered by the existence of countless genetic variants sharing poor cross-protection. A retrospective study was conducted on IBV positive samples collected in Italian broiler farms from 2012 to 2019. In 2015, the adopted vaccination protocol shifted from a Mass and 793B-based vaccines to the administration of Mass and QX vaccines, allowing to study how changes in vaccination strategies may affect IBV epidemiology, control and diagnosis in the field. The most frequently detected lineages were QX (70.3%), 793B (15.8%) and Mass (11.9%). The relative frequencies of QX and 793B detections remained stable throughout the study, while Mass detections significantly increased after the vaccination change. Rather than to an actual growth of Mass population size, this finding may be attributable to different vaccine interactions, with Mass strains being more frequently concealed by 793B vaccines than by QX ones. Based on the obtained results, the two vaccination protocols appear to be similarly effective in fighting IB outbreaks, which in the last decade have been caused primarily by QX field strains in Italy. These results indicate that vaccination strategies may significantly affect IBV epidemiology and diagnosis, and should therefore be considered when choosing and interpreting diagnostic assays and planning control measures.
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The aim of this study was to clone, express and identify the truncated S1 gene of nephrotropic infectious bronchitis virus (IBV) and granulocyte-monocyte colony stimulating factor (GM-CSF) of chicken. Firstly, two genes were amplified by polymerase chain reaction (PCR) and cloned into pMD18-T vector. The truncated S1 gene designated as Sf200 containing five antigenic sites of S1 glycoprotein on amino acid residues (aa) 24-61, (aa) 291-398 and (aa) 497-543 and GM-CSF were then amplified from the respective recombinant pMD18-T plasmids and cloned into pET-32a (+) vector resulting pET-Sf200, pET-GM which were identified by restriction enzyme digestion and sequencing analysis. The in vitro expression of truncated Sf200 and GM-CSF constructs were later expressed in E. coli BL21 with a molecular mass of approximately 38 kDa and 29 kDa respectively as judged by sodium dodecyl sulfate-polyacrylamide gel electrophoresis analysis. Polyclonal antibodies were developed by injecting E. coli expressed Sf200 and GM-CSF into the SPF mice and were used to identify the recombinant proteins by Western blot analysis. These findings indicated that the polyclonal antibodies produced in mice could be used to detect the recombinant truncated Sf200 and GM-CSF and vice versa.
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Objective: Epidemiology and genetic variations of the infectious bronchitis virus(IBV) in Fujian province were studied. Method: Two strains of virus isolated from the diseased chickens in Fujian in 2021 were identified by chicken embryo pathogenicity test, electron microscope observation, and RT-PCR. S1 genes of the isolates were cloned, sequenced, and analyzed using biological software. Result: The two IBV strains were code named FJ-NP01 and FJ-FZ01. The full length of S1 of FJ-NP01 was 1 629 nt encoding 543 amino acids, and that of FJ-FZ01, 1 620 nt encoding 540 amino acids. The S1 gene cleavage site of FJ-FZ01 was HRRRR, same as all reference strains of genotype I branch;while that of FJ-NP01 HRRKR differed from the reported site of IBV isolated from genotype IV but same as that of TC07-2 reference strain of genotype VI. The homology of nucleotide and amino acid between the two isolates was 83.2% and 79.6%, respectively, but merely 75.7%-76.3%and 77.1%-83.5% with the Mass-type conventional vaccines H120 and H52, respectively. Further analysis showed that FJ-NP01was from a recombination event between CK CH GD LZ12-4 and L-1148, the homology of nucleotide acid between 1438-1506 nt of FJ-NP01 with CK CH GD LZ12-4 was 97%, and 95.9% between the other nucleotide acid of S1 gene with L-1148. Conclusion: It appeared that the IBV epidemic experienced in the province was complex in nature and that the existing Mass vaccines would not provide sufficient immune protection to deter the spread.
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[Objective] To prepare broad-spectrum monoclonal antibody against N protein of avian infectious bronchitis virus (IBV), so as to lay a foundation for identifying conservative domain epitope of N protein and establish a universal IBV detection method. [Method] N protein of GX-YL5, a representative strain of IBV dominant serotype in Guangxi, was expressed in prokaryote. BALB/c mice were immunized with the purified protein. After the serum titer of the immunized mice reached 104 or more, the splenocytes were fused with SP2/0 myeloma cells. After screening by indirect ELISA, monoclonal antibody was prepared by ascites-induced method. Western blotting, IFA and indirect ELISA were used to identify the titer, subtype, reaction specificity and cross-reaction spectrum. And the prepared monoclonal antibody was used for immunohistochemical detection. And the prepared monoclonal antibody was used to detect the IBV in the trachea and kidney tissues of SPF chickens artificially infected with 4 representative IBV variants (GX-N130048, GX-N160421, GX-QZ171023 and GX-QZ170728). [Result] The prepared monoclonal antibody N2D5 had a titer greater than 217 and its subtype was IgG2b. The Western blotting and IFA results showed that the monoclonal antibody N2D5 only reacted with IBV, and were negative with Newcastle disease virus (NDV), infectious laryngotracheitis virus (ILTV), avian metapneumovirus (aMPV), infectious bursal disease virus (IBDV), avian leukosis virus (ALV) and Marek's disease virus (MDV). Monoclonal antibody N2D5 reacted with many genotypes in China and all 7 serotypes of IBV currently prevalent in Guangxi, including commonly used standard strains, vaccine strains and field strains. Immunohistochemistry showed that the virus signals could be detected in the trachea and kidney tissues of SPF chickens at different time after artificial infection of 3 representative IBV strains from chicken and 1 isolated strain from duck, which further proved its broad spectrum. [Conclusion] The monoclonal antibody N2D5 of IBV prepared based on hybridoma technology belongs to the IgG2b subtype. It has the characteristics of high specificity, wide response spectrum and strong binding ability with IBV. It can be used as a specific diagnostic antibody for clinical diagnosis of IBV and the study of virus distribution.
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In order to perform the isolation of avian infectious bronchitis virus (IBV) and study the pathogenicity of IBV isolate, the RT-PCR was used to detect nucleic acid extracted from a clinical sample of chickens, which were suspected to be infected with infectious bronchitis virus (IBV) and provided by a farmer in Yuncheng, Shanxi province. And the sample was detected as IBV positive by RT-PCR. Then 9-11-day-old SPF chicken embryonated eggs were inoculated with the sample filtered from the grinding fluid, and the obtained allantoic fluid was blindly passed by three generations (F3) and was also tested as IBV positive;The F11 generation passaged in embryonated eggs caused typical "dwarf embryo" lesions to SPF chicken embryonated eggs, and induced the loss of cilia in tracheal rings. The results showed that an IBV strain was isolated and named as YC181031. The S1 gene amplification and sequencing analysis showed that YC181031 strain belonged to IBV GI-22 genotype, which is also nephropathogenic type IBV. Seven-day-old SPF chicks were used to test the pathogenicity of the isolate. The results showed that several clinical symptoms were showed in chicks infected with YC181031, such as breathing with difficulty, depression, excreting watery droppings and death. The mortality of infected chicks was 20%. Typical pathological changes such as enlargement of kidney and urate deposition in the kidney were observed in infected chicks. The immunohistochemical assay and viral load detection were performed for the tissue samples from infected and dead chicks. The tissue lesions and distribution of virus were observed in the kidney, trachea, lung, glandular stomach, spleen and liver samples of infected chicks. RT-PCR detection of pharyngeal anal swabs showed that the virus shedding by infected chicks could be continuously detected within 14 days of the test period;The viral loads of various tissues were detected by RT-qPCR and the results showed that the viral load from high to low was kidney, trachea, lung, stomach, spleen and liver. The viral load of kidney was significantly higher than that of other tissues (P < 0.05).In this study, the pathogenicity characteristics of GI-22 genotype strain were systematically studied for the first time, providing a reference for the prevention and treatment of the disease.
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The purpose of this experiment was to increase poultry meat production by increasing the number of chickens reared in the same area and managing it by using medicinal herbs Salvia officinalis L and Lavandula angustifolia L. in the broiler chicken diet. 705 one-day-old chicks were randomly distributed into to7 treatments with three replicates for an area of two m2 floor system in each replicate for each treatment, during 35 days of the study. T0 negative control 75 chicks, 25 chicks for each replicate 12-13 chicks per m2 fed standard diet. T1 positive control (stocking density without supplementation)105 chicks, 35 each replicate chicks 17-18 per m2 fed standard diet. The same stocking density for T2, T3, T4, T5, and T6 have been given standard feed with supplemented herbals, salvia 0.7%, 0.9%, lavender0.7%, 0.9%, and mixed 0.7% respectively. Depending on the results, chickens reared in stress stocking density with supplementations led to higher improvement of body weight, meat production, body weight gain (BWG), feed conversion ratio(FCR g feed/g weight), production index PI, carcass weight (g) and dressing percentage, RBCs 106cells/mm3, lymphocyte%, of increasing activity of thyroid hormones T3, T4 (nmol/L) boost antibody titers of ND and IBV when compared with positive control. However, heterophil%, stress indicator H/L ratio, glucose mg/ dL and cholesterol mg/ dL significantly reduced. The results showed that adding sage and lavender plants to broiler feed is effective in improving productivity, immunity, and resistance characteristics in reducing the adverse effects of stress caused by increasing the intensity of broiler rearing in the same area.
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Protecting livestock against diseases by enhancing its immunity is essential and required in poultry industry. Therefore, the aim of the present study was to evaluate the possible immunoenhancing effects of Inosine-Acedoben-Dimepranol (IAD) in broiler chicks. A total of 150 chicks were used in the present study, divided into 6 groups (25 for each) and subjected to different treatments. It has been found that IAD significantly (P 0.05) increased total leukocytic count, with increased granulocyte (neutrophils, eosinophils, basophils), lymphocyte and monocyte counts compared to control chicks. IAD significantly (P 0.05) increased total protein as a result of increased globulins in plasma when compared with those of control. IAD has been found to significantly (P 0.05) increase immune response of IB vaccine in IAD + IB vaccine-treated groups compared to control measured by ELISA. IAD exhibited antiviral effect indicated by increased survival percent of chicks challenged with virulent IB virus with survival 100% in the groups received IAD large dose plus vaccine. Data of the present study may indicate that supplying chicks with IAD in drinking water is a good recommendation in poultry industry based on its immune enhancing properties.
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The Indian poultry market is estimated to have an annual growth rate of 8.1% as of today. However, infectious diseases in poultry pose an important constraint in the growth and development of this sector in our region. Among infectious diseases, viral diseases of poultry pose a serious threat to the poultry industry from an economic point of view. Several viral disease outbreaks have been reported by various researchers from different parts of the country. Among the common viral diseases of poultry, incidences of Newcastle disease, Avian Influenza, Fowl Pox, Infectious Bursal Disease, Marek's disease, Infectious Bronchitis, Infectious Laryngotracheitis and Inclusion Body Hepatitis are significant in Assam as well as other parts of India. Thorough epidemiological studies followed by the identification of different serotypes, pathotypes, strains, etc. by genotyping and molecular characterization of viral disease pathogens may lead to ways to control and eradicate the diseases. Importance should be given to maintaining basic preventive measures like biosecurity, farm hygiene, and proper vaccination. In a developing country like India, disease outbreaks can impact the country's economy. In this study, a brief view of the common viral disease of poultry and its diagnosis and control strategies in Assam, India is depicted. However, this review well indicates a plethora of avian diseases that have occurred over the years causing a severe impact on poultry farming as a whole.
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Avian infectious bronchitis (IB) is one of the acute and highly contagious upper respiratory tract infectious diseases in poultry caused by the Infectious bronchitis virus (IBV), which significantly affects the health and development of world poultry farming industry. IBV RNA polymerase lacks a complete correctional function and is prone to gene mutation and RNA-RNA recombination during the replication process, resulting in the emergence of new serotypes, genotypes and mutant strains. The continuous generation of recombinant strains through homologous recombination between strains also complicates the prevention and control of IB. Therefore, monitoring the genetic evolutionary characteristics of circulating strains and evaluating the protective effect of commonly used vaccines against local circulating strains of IBV are the keys to preventing and controlling this disease.
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Poultry industry is dynamically developing worldwide, and the threat from infectious viral diseases also increases. One of them is an acute, highly contagious avian infectious bronchitis (IB), caused by infectious bronchitis virus (IBV), the coronavirus of the fowl. IBV is characterized by extensive variations in the surface spike protein gene. Those genetic variations lead to rapid changes in IBV serotypes that need to be constantly monitored to assess the epidemiological situation in the field. The aim of this article was to present current knowledge and recent epidemiology, based on IBV field strains circulation. Several serotypes can be simultaneously present in a region and as they cross-protect poorly, broiler chickens can be infected more than once within their short period of life. Careful, constant monitoring is necessary to respond fast in case of new genetic IBV variants development. Some of these strains have global range, while the prevalence of others is limited to some geographical areas. Thus, the understanding the IB epidemiology, virus spread and the occurrence of individual strains allows to use the optimal vaccination schedule to limit the disease and improve the poultry production. Finaily, a good recognition of the IB problem in Central and Eastern Europe on the example of Poland as the largest European poultry producer, can be a key factor in the quickest response to emerging new IBV variants. Some practical solutions may help to introduce the similar and effective procedures also in other regions of the world with high intensity of poultry production.
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Air pollution in the environment in which poultry is raised is one of the most serious problems facing the poultry sector across various aspects of production. Perhaps the most dangerous gas emitted from poultry houses is ammonia. The high concentrations of this gas in the air above the permissible limits (15 ppm) will have disastrous consequences. Ammonia directly affects the health and safety of birds, as it is a cause of ammonia blindness in birds accompanied by many respiratory diseases that destroy production and increase breeding costs. In addition, high concentrations of ammonia (above 20 ppm) contribute to enhancing the infection of birds with Newcastle and the bronchitis virus. In general, the greenhouse gases emitted from poultry houses included four main gases (carbon dioxide, nitrous oxide, methane and hydrogen sulphide). Studies regarding their direct effects on the health and productivity of birds have been insufficient. In the direct form, as the concentrations of greenhouse gases rise to very high limits, they cause suffocation and death., the behaviour of the greenhouse gases in the indirect effect is reflected being a source of nutritional stress and a group of diseases and parasites which lead to a decrease in productivity levels. The intensity and concentrations of gas emissions are directly related to many factors such as geographic location, the season of the year, ventilation technologies, humidity, litter quality, nutritional status and stocking density. The advances in ventilation technologies have played a key role in expelling all harmful gases, especially those that depend on negative pressure. However, greenhouse gases remain a real threat to the poultry industry in particular and to the planet's environment in general.
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Proper control of infectious bronchitis, pursued through strict biosecurity and mass vaccination, is essential in intensive broiler production. Despite effective and routinely adopted, hatchery spray vaccination has been hypothesized to affect body temperature and wellbeing of day-old chicks. Recently, gel administration has been proposed as an alternative and proved feasible in experimental settings. In this study, IBV spray and gel vaccination were compared in field conditions. One hundred birds from the same hatch were vaccinated, half by spray and half by gel, with 793B and Mass vaccines. After vaccination, rectal temperature was measured and vaccine intake assessed. The two groups were raised for 35 days in separate pens, and swabs and blood samples were collected at multiple time points for lineage-specific molecular analyses and serology, respectively. Temperature was significantly lower in spray vaccinated chicks 10 minutes and an hour after administration. A similar trend in 793B titres was observed in both groups, while Mass-based vaccine was detected later but persisted longer in gel vaccinated chicks. No differences were observed in mean antibody titres. Compared to spray, gel administration appears equally effective and less impactful on body temperature, thus supporting its application for IBV vaccmatlon.
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Avian infectious bronchitis (IB) is an economically important, highly contagious, acute disease of Chickens caused by a single-stranded positive RNA Virus that belongs to the Coronaviridae family. The Virus can replicate in the oviduct and cause permanent damage in young hens resulting in the false layer occurrence. In laying hens, infectious bronchitis Virus (IBV) infections can cause a severe decline in egg production and a number of effects on egg quality and reduced hatchability. The most effective means of controlling IB in poultry is vaccination. In the areas with increased pressure of circulating field challenge Virus, live attenuated vaccines are also used during the laying period with the intention of keeping local protection of the respiratory tract at a high level. The vaccine strain IB V-173/11 contained in Avishield IB GI-13 vaccine is a strain that genetically (S1 gene) belongs to GI-13 lineage and antigenically to 793B IBV serotype. Viral infections of this serotype occur frequently in Europe and therefore most vaccination programs in broilers, layers and breeders along a live IBV vaccine of the Massachusetts serotype also include a live vaccine of the 793B serotype, GI-I3 lineage. In this paper, results of a safety evaluation of live attenuated IB vaccine strain V-173/11, when administered by spray method in a ten-fold maximum dose repeated by one maximum dose in 28-week-old specific pathogen free (SPF) layer Chickens are presented. As a control, non-vaccinated SPF layer chickens were included in the study. The vaccine is considered to be safe when used in laying period because no vaccinated chicken showed abnormal local or systemic reactions or signs of IB related disease, no chicken died from the causes attributable to the vaccine, egg quality was not altered, and there was no statistically significant difference in. egg production between the vaccinated and non-vaccinated group.
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Broiler population is one of the most important segments of livestock due to its significant contribution in white meat production. Infectious disease outbreaks adversely influence the production potential and consequently cause economic losses. Epidemiological data regarding magnitude of these disease outbreaks is of fundamental importance for planning of a comprehensive control strategy. With retrospective design, this study was conducted from January 2013 through December 2017 in order to assess the disease burden on broilers reared in different open type poultry houses. Out of total 658 commercial farms with capacity of 4221800 broilers, across Chakwal, a representative sample of 70 farms with capacity of 448000 broilers was randomly selected for collection and analysis of disease data. Five years' data of these randomly selected farms revealed highest (44.64%) crude morbidity during monsoon season followed by 23.92%, 22.12% and 17.49% for winter, spring and post-monsoon seasons respectively. The highest (14.90%) prevalence was recorded for new castle disease followed by infectious bursal disease (11.79%), pullorum disease (11.17%), colibacillosis (8.71%), infectious bronchitis (7.87%), inclusion body hepatitis (7.79%), chronic respiratory disease (7.67%), necrotic enteritis (6.48%), coccidiosis (6.09%), mycotoxicosis (5.43%), fowl cholera (4.74%), infectious coryza (4.41%), fowl typhoid (4.22%), omphalitis (3.71%) and hydropericardium syndrome (0.05%). Maximum share in crude morbidity was contributed by bacterial diseases with highest proportional morbidity of 48.68% followed by viral (40.32%), parasitic (5.80%) and fungal (5.20%) diseases. This epidemiological data represents true picture of study population and is a valuable tool for planning of prevention strategy and research priorities.
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The effects of heat shock protein HSPQOABl on the replication of avian infectious bronchitis virus(AIBV) were confirmed by using over expression and RNA interference methods. The results showed that over expression of HSPQOABI inhibited AIBV replication, whereas knockdown of HSPQOABl in- creased AIBV replication. These results indicated that HSPQOABI is a potential anti-viral host factor. These findings provide the basis for further study of the pathogenic mechanism of AIBV and anti-coronavirus infection.
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Emergence of avian infectious bronchitis virus (IBV) variants with altered tissue tropism and host range has been reported from different parts of the world. Little is known about the different IBV variants existing and emerging in India. To explore the same, an IBV isolate, namely B17 isolated from backyard chicken in Tamil Nadu was used in the present study. The complete genome of B17 was sequenced and its phylogenetic relationship with the existing vaccine strain genotypes was analysed. The phylogenetic analysis of both S1 gene and complete genome sequence grouped B17 under Mass41 genotype comprising of M41, Beaudette, H120 and H120 variant with bootstrap value of 95-100%. Further, genomic analysis of B17 revealed the possibilities of emergence of the same from H120 vaccine strain through mutations at various genes.
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The aim of this study was to determine the hematological profile and specific immunity of laying hens with the addition of oil extracts of lycopene or astaxanthin to the diet. The study used High Line W36 chickens that were vaccinated against Newcastle disease, infectious bronchitis, avian rhinotracheitis and egg drop syndrome. It was found that the addition of lycopene (20 mg/kg) and astaxanthin (10 mg/kg) for 30 days did not affect the hematological profile of laying hens. Increasing the content of lycopene to 40 and 60 mg/kg or astaxanthin to 20 or 30 mg/kg of feed for 30 days reduced the number of leukocytes and hemoglobin in the blood compared to the control, which received an equivalent amount of refined sunflower oil in the diet. Lycopene and astaxanthin supplements, regardless of dose and duration of administration, did not affect the titer of antibodies to Newcastle disease, infectious bronchitis, avian rhinotracheitis, and egg drop syndrome in serum of vaccinated laying hens. The obtained data can be used to justify the optimal dose and term of feeding of lycopene or astaxanthin supplements in the development of a model of carotenoid enrichment of chicken egg yolks.
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The informal poultry and pig sector in the Eastern Cape Province (ECP) of South Africa is of significant socio-economic importance as it sustains livelihoods and ensures food security;yet little is known about the distribution and prevalence of infectious and zoonotic diseases in this region. This paper reviews data published for pig and poultry diseases in the province during the last 20 years (2000-2020). The review included relevant published papers identified by a computerised literature search from Web of Science;provincial animal health reports;the national database from the Department of Agriculture, Land Reform and Rural Development (DALRRD);animal health reports submitted by DALRRD to the World Organisation for Animal Health (OIE) via the World Animal Health Information Database (WAHID) interface and laboratory records. A publication was considered eligible if it included qualitative or quantitative information on any disease affecting pigs and poultry including zoonosis. The search retrieved 174 publications, of which 26 were relevant. The review found that Newcastle disease (ND), coccidiosis and fowl pox (FP) were the most reported avian diseases in the national database, whereas avian infectious bronchitis (AIB), ND and highly pathogenic avian influenza (HPAI) were the most reported diseases in the OIE database. Classical swine fever (CSF) was the most reported pig disease in both databases. The retrieved literature on pig and poultry diseases was scarce and no longer up to date, providing decision makers with little information. The review identified important zoonotic diseases that require further studies yet failed to find information on important neglected diseases like leptospirosis.
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Backyard poultry is evolving as a fast-growing sector in recent times across the world. Apart from providing nutritional security, and livelihood to marginalized sector, also fulfils the demand for organic and welfare meat and eggs. However, the productivity is often challenged by incidences of diseases due to poor biosecurity and lack of vaccination. In this study, systematic review and meta-analysis were performed on the global prevalence of infectious diseases in backyard chickens. A total of 22 bacterial, viral, parasitic and fungal diseases were reported from 55 publications between 2000 and 2020 worldwide. Viral diseases were the most reported followed by bacterial and parasitic diseases. 61 out of 91 studies from 55 publications investigated seven major diseases: Avian influenza (AI), Newcastle disease (ND), infectious bronchitis (IB), Mycoplasma gallisepticum (MG), Mycoplasma synoviae (MS), Salmonella infection, and infectious laryngotracheitis (ILT). The overall pooled prevalence estimate for all the diseases worldwide was 33% (95% confidence interval (CI): 28-38). The pooled estimates for most reported viral diseases AI and ND were 12.5% (95% CI: 7-18) and (30% CI: 19-43), respectively. IBD (71% CI: 13-100), MS (76% CI: 67-85) and helminth infestations (72% CI: 44-93) were the highly prevalent diseases among viral, bacterial and parasitic infections, respectively. The continent wise pooled prevalence ranged from 17 to 32%. The present results will help in devising the best possible strategies to minimize the disease risk for commercial poultry and humans as well as for improving the productivity of backyard poultry farming.