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Many zoonotic diseases are found in wild animals and present a serious risk to human health, in particularly the virus carried by birds flying freely around the world is hard to control. There are three main bird migration routes which cover the most areas of China. It is important to investigate and fully understand the types of avian transmitted diseases in key areas on the bird migration routines and its impacts on both birds and human health. However, no literature is available in how about the risk of virus carried by migrating birds, and how to predict and reduce this risk of virus spreading to human being so far. In this paper, we first reviewed the main pathogen types carried by birds, including coronaviruses, influenza viruses, parasites, Newcastle disease virus (NDV), etc., and then discussed the spread risk of avian viruses to human being and animals in key areas of biosafety prevention. We also analyzed and discussed the risk of cross-spread of diseases among different bird species in nature reserves located on bird migration routes which provide sufficient food sources for migratory birds and attract numerous birds. Diseases transmitted by wild birds pose a serious threat to poultry farms, where high density of poultry may become avian influenza virus (AIV) reservoirs, cause a risk of avian influenza outbreaks. Airports are mostly built in suburban areas or remote areas with good ecological environment. There are important transit places for bird migration and densely populated areas, which have serious risk of disease transmission. Finally, this paper puts forward the following prevention suggestions from three aspects. First, establish and improve the monitoring and prediction mechanism of migratory birds, and use laser technology to prevent contact between wild birds and poultry. Second, examine and identify virus types carried by birds in their habitats and carry out vaccination. Third, protect the ecological environment of bird habitat, and keep wild birds in their natural habitat, so as to reduce the contact between wild birds and human and poultry, and thus reduce the risk of virus transmission.
ABSTRACT
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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Objective: To investigate the genetic diversity of coronaviruses in wild and domestic birds in the bird park and live poultry markets of Ca Mau province in Vietnam in 2020. Methods: A total of 228 samples (121 from wild birds and 107 from poultry) were collected in the territory of Ca Mau province of Vietnam in 2020. The avian samples were tested for the presence of the four genera of coronaviruses using reverse transcription and nested PCR. Molecular genetic analysis using targeted NGS sequencing of RdRp gene was performed for 29 representative samples (12 samples from wild birds and 17 from poultry). Phylogenetic analysis was performed using the neighbour joininig method with 1000 bootstrap replications using MEGA X software. Results: Among wild birds, 21.5% samples were positive for the genetic material of coronaviruses and 38.3% samples were positive for coronaviruses among poultry. Genetic analysis of the partial sequence of RdRp gene from representative samples revealed that wild birds were carriers of gammacoronaviruses and deltacoronaviruses. Among poultry, three genotypes of infectious bronchitis virus (QX, Mass and Q1) were detected in chickens, with QX genotypes being predominant, and viruses of DCoV group were detected in domestic ducks. There was no detection of alphacoronaviruses or betacoronaviruses in the studied birds. Conclusions: Coronaviruses of genera Gammacoronavirus and Deltacoronavirus were detected in wild birds. A high percentage of infectious bronchitis virus was detected in poultry. Thus, there is a need for broader surveillance of coronaviruses in birds, which can be used for evaluation of diversity, evolution and distribution of coronaviruses in Vietnam. Continuous surveillance of coronaviruses circulation in wild and domestic animals is necessary for implementing strategic measures for poultry and domestic animal protection and for evaluation of possible risk of circulating coronaviruses to human health.
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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.
ABSTRACT
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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Background: Infectious laryngotracheitis (ILT) and infectious bronchitis (IB) are two common respiratory diseases of poultry that inflict great economic burden on the poultry industry. Developing an effective agent against both viruses is a crucial step to decrease the economic losses. Therefore, for the first time green synthesized silver nanoparticles using Cyperus rotundus L. aqueous extract was evaluated in vitro as a potential antiviral against both viruses. Results: Silver nanoparticles from Cyperus rotundus were characterized by the spherical shape, 11-19 nm size, and zeta potential of - 6.04 mV. The maximum nontoxic concentration (MNTC) was 50 mu g mL(-1 )for both viruses without harmful toxicity impact. The study suggested that some of the compounds in C. rotundus extract (gallic acid, chlorogenic acid, and naringenin) or its silver nanoparticles could interact with the external envelope proteins of both viruses, and inhibiting extracellular viruses. Conclusions: The results highlight that C. rotundus green synthesized silver nanoparticles could have antiviral activity against infectious laryngotracheitis virus (ILTV) and infectious bronchitis virus (IBV) in chickens.
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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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Infectious bronchitis virus (IBV) is a member of the family Coronaviridae, together with viruses such as SARS-CoV, MERS-CoV and SARS-CoV-2 (the causative agent of the COVID-19 global pandemic). In this family of viruses, interspecies transmission has been reported, so understanding their pathobiology could lead to a better understanding of the emergence of new serotypes. IBV possesses a single-stranded, non-segmented RNA genome about 27.6 kb in length that encodes several non-structural and structural proteins. Most functions of these proteins have been confirmed in IBV, but some other proposed functions have been based on research conducted on other members of the family Coronaviridae. IBV has variable tissue tropism depending on the strain, and can affect the respiratory, reproductive, or urinary tracts; however, IBV can also replicate in other organs. Additionally, the pathogenicity of IBV is also variable, with some strains causing only mild clinical signs, while infection with others results in high mortality rates in chickens. This paper extensively and comprehensibly reviews general aspects of coronaviruses and, more specifically, IBV, with emphasis on protein functions and pathogenesis. The pathogenicity of the Australian strains of IBV is also reviewed, describing the variability between the different groups of strains, from the classical to the novel and recombinant strains. Reverse genetic systems, cloning and cell culture growth techniques applicable to IBV are also reviewed.