Six decades of infectious bursal disease in poultry: The journey so far and challenges ahead

Despite six decades of concerted efforts, Infectious bursal disease (IBD) still remains a major threat to the poultry industry worldwide. Most importantly, the emergence of variant and very virulent strains of infectious bursal disease virus (IBDV) has dramatically changed the epidemiology of the disease, thus resulting in the renewed efforts in the search for effective control measures. Currently, live attenuated, inactivated, and immune-complex vaccines are among the immune-therapeutic approaches employed for the control of IBD in the field alongside adequate biosecurity, albeit with various degrees of success and limitations. Progress in genetic engineering has allowed the generation of reverse genetic IBDV mutants, recombinant live viral vectors expressing the IBDV VP2 immunodominant protein, intra-serotypic recombinant IBDV viral-like particle co-expressing the outer capsid protein structures derived from 2 or more serotype 1 strains or the incorporation of either VP2 or VP2-4-3 polyprotein sequences alongside molecular adjuvants that can be used as IBD vaccine candidates to elicit an immune response. However, despite these advances, outbreaks are still reported even in flocks that have up to date vaccination records and somewhat excellent management practices. This paper reviews aspect of genetic characteristics of IBDV and reflects on the progress and future challenges in providing effective IBD vaccine to achieve effective control of both classical and very-virulent IBDV serotypes that constitute a major devastation to poultry production and health.

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Directed evolution of Metarhizium fungus improves its biocontrol efficacy against Varroa mites in honey bee colonies

Scientific Reports ◽

10.1038/s41598-021-89811-2 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Jennifer O. Han ◽

Nicholas L. Naeger ◽

Brandon K. Hopkins ◽

David Sumerlin ◽

Paul E. Stamets ◽

...

Keyword(s):

Directed Evolution ◽

Honey Bee ◽

Entomopathogenic Fungi ◽

Management Practices ◽

Abiotic Factors ◽

Control Measures ◽

Residual Effects ◽

Effective Control ◽

Great Promise ◽

Bee Colonies

AbstractEntomopathogenic fungi show great promise as pesticides in terms of their relatively high target specificity, low non-target toxicity, and low residual effects in agricultural fields and the environment. However, they also frequently have characteristics that limit their use, especially concerning tolerances to temperature, ultraviolet radiation, or other abiotic factors. The devastating ectoparasite of honey bees, Varroa destructor, is susceptible to entomopathogenic fungi, but the relatively warm temperatures inside honey bee hives have prevented these fungi from becoming effective control measures. Using a combination of traditional selection and directed evolution techniques developed for this system, new strains of Metarhizium brunneum were created that survived, germinated, and grew better at bee hive temperatures (35 °C). Field tests with full-sized honey bee colonies confirmed that the new strain JH1078 is more virulent against Varroa mites and controls the pest comparable to current treatments. These results indicate that entomopathogenic fungi are evolutionarily labile and capable of playing a larger role in modern pest management practices.

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Comparative proteomic analysis of Fusarium oxysporum f. sp. cubense strains (Foc R1 and Foc TR4) provides better insights into mechanisms of their virulence, habitat adaptation and pathogenesis

10.1101/2021.12.29.474485 ◽

2021 ◽

Author(s):

Thangavelu Raman ◽

Kalaiponmani Kalaimughilan ◽

Edwinraj Esack

Keyword(s):

Fusarium Oxysporum ◽

Management Practices ◽

Response Regulator ◽

Control Measures ◽

Effective Control ◽

Ph Response ◽

Molecular Approaches ◽

Regulator Protein ◽

Fructose 1,6 Bisphosphate ◽

Related Proteins

Fusarium oxysporum f. sp. cubense (Foc), a devastative soil-borne fungal pathogen causing vascular wilt (i.e. Panama disease) which leads to severe crop losses in most of the banana-growing regions of the world. As there is no single source of effective management practices available so far, understand the pathogenicity of the organism may help in designing effective control measures through molecular approaches. The study aims to compare the proteome of the two pathogenic Foc virulent strains, Race 1 (Foc R1) and tropical race 4 (Foc TR4) that are capable of infecting the Cavendish group of bananas using 2-dimensional (2-D) gel electrophoresis, MALDI-TOF/MS and MS/MS analysis. The results of the study revealed that the proteins, peroxiredoxins, NAD-aldehyde dehydrogenase (NAD-ALDH), MAPK protein, pH-response regulator protein palA/rim-20 and isotrichodermin C15 hydroxylase have shared homology with the fungal proteins, which regulate the osmotic stress response, signal transduction, root colonization and toxin biosynthesis. These are the important functions for the pathogen survival in an unfavourable environment, and successful establishment and infection of the banana host. The present study also identified several putative pathogenicity related proteins in both Foc R1 and Foc TR4. Specifically, certain Foc TR4 specific putative pathogenicity related proteins, phytotoxins biosynthesis gene, fructose 1,6-bisphosphate aldolase class II, Synembryn-like proteins found to contribute strong virulence. Overexpression or knockout of the elective genes could help in devising better control measures for the devastative pathogens in the future. To the best of our knowledge, this is the first report on the proteomics of Foc R1 and Foc TR4 strains of Indian origin that infect Cavendish bananas.

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DISEASES OF POULTRY IN ZARIA, NIGERIA: A TEN YEAR ANALYSIS OF CLINIC RECORDS

Nigerian Journal of Animal Production ◽

10.51791/njap.v25i1.2269 ◽

2021 ◽

Vol 25 (1) ◽

pp. 88-92

Author(s):

P. D. HALLE ◽

J. U. UMOH ◽

L. SAIDU ◽

P. A. ABDU

Keyword(s):

Respiratory Disease ◽

Newcastle Disease ◽

Rainy Season ◽

Chronic Respiratory Disease ◽

Infectious Bursal Disease ◽

Viral Diseases ◽

Poultry Production ◽

Bursal Disease ◽

Poultry Disease ◽

Health Programme

A 10-year study of poultry diseases diagnosed at the Avian clinic of Veterinary Teaching Hospital, Ahmadu Bello University, Zaria was conducted. In all 2999 cases were studied. The commonest diseases afflicting poultry were Newcastle disease, 31.2%, Gumboro 12%, Ectoparasitism 7.7%, Fowl pox 6.8%, Helminthiasis 6.6% and Coccidiosis 6.1%. Most outbreaks occurred in the months of May and June with the highest incidence in 1989. Fowl pox (EP), infectious bursal disease (IBD) and coccidiosis were more prevalent during the rainy season (May-October) while Newcastle disease (NCD) and Aspergillosis were more prevalent in the dry season (November - April). More cases of chronic respiratory disease (CRD), helminthiasis and salmonellosis were found in poultry over 12 weeks old while gumboro, fowl pox and coccidiosis were found more in birds less than 7 weeks old. It was concluded from this study that viral diseases (NCD, IBD, FP) ectoparasitism and helminthiasis were the most important poultry disease in Zaria and young birds were more susceptible. The need for an effective poultry health programme is imperative. It is therefore recommended that effective and uniform vaccinations schedules should be conducted along with regular deworming and ectoparasite control to enhance poultry production

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INFECTIOUS BURSAL DISEASE (GUMBORO DISEASE)

Archives of Veterinary Medicine ◽

10.46784/e-avm.v1i1.219 ◽

2008 ◽

Vol 1 (1) ◽

pp. 5-17

Author(s):

Maja Velhner

Keyword(s):

Rna Virus ◽

Genetically Engineered ◽

Bursa Of Fabricius ◽

Infectious Bursal Disease ◽

Antigenic Structure ◽

Economic Losses ◽

Oil Emulsion ◽

Live Vaccines ◽

Bursal Disease ◽

Serotype 1

Infectious bursal disease (IBD) is widespread in many countries with intensive poultry industry. The causative agent is an RNA virus that belongs to Birnaviridae family. Two serotypes of IBDV exist. Serotype 1 strains originate from chickens, while serotypes 2 viruses are isolated from turkeys. Serotype 1 strains are further divided as classical, variant and very virulent. All the categories of young chickens are prone to the disease. Due to resultant immunosuppression the birds are exposed to secondary bacterial and viral infection that causes additional economic losses. The virus multiplies in the bursa of Fabricius inducing lymphocyte depletion (all strains) and inflammation (classical and very virulent strains). Approximately four days post infection, atrophy of bursa occurs followed by recovery process. Spleen, thymus and bone marrow are also damaged and the intensity of damage depends on the virus involved. Damages of these organs could be detected by pathohistological examination. The inflammatory response in bursa coincides with strong influx of CD3+ cells that take part in virus clearance and recovery. The disease can be controlled by the application of vaccination. Parent flocks are vaccinated with oil emulsion vaccines providing transfer of maternally derived antibodies to the progeny. In this way chickens are protected at an early age, while live vaccines provide protection during rearing. Live vaccines are classified as mild, intermediate and “hot”. Stronger vaccines can overcome high levels of maternal antibodies more efficiently and are recommended in questionable filed situation. Such vaccines may cause destruction of the bursa followed by a quick and full recovery. The knowledge about the antigenic structure of the virus leads to the production of genetically engineered vaccines that could be used in the future.

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Critical Appraisal of Management Practices in Nepalese Guava Orchards

Journal of the Institute of Agriculture and Animal Science ◽

10.3126/jiaas.v26i0.665 ◽

2005 ◽

Vol 26 ◽

pp. 127-133 ◽

Cited By ~ 1

Author(s):

AK Shrestha

Keyword(s):

Management Practices ◽

Critical Appraisal ◽

Psidium Guajava ◽

Control Measures ◽

Effective Control ◽

Peak Period ◽

Rainfed Condition ◽

Guava Fruit ◽

Production Constraints ◽

June July

A survey was conducted to appraise the guava farming in Nepal with respect to the orchard management practices, cultivar status and major production constraints during July- December 2001. Guava plantation was extensively distributed throughout terai, inner terai and mid hill districts ranging in altitude from 115 masl to 1600 masl. Indian varieties dominated the guava plantation in Nepal although mix population of both improved and local cultivars was reported in majority of orchards. Preponderance of seedling origin guava plantation was noticed. The management practices were poor. Over 80% of the orchards received neither FYM nor chemical fertilizer. Similarly, more than 90% of the orchards were under rainfed condition. The peak period of flowering was reported during April/May followed by Feb/March that may extend up to June/July. As a consequence, the fruit availability period is mainly restricted to four months, i.e. July/ August to Oct/Nov. Most of the growers pointed out guava wilt as the main biotic constraint in guava production. The outcomes indicted the urgent need to adopt the effective control measures against the guava wilt malady to flourish guava enterprise in Nepal. Furthermore, off-season production of guava fruit has the great potential in Nepalese market. Key words: cultivar, guava wilt, orchard, Psidium guajava J. Inst. Agric. Anim. Sci. 26:127-133 (2005)

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Chemiluminescent Detection of Infectious Bursal Disease Virus with a PCR-Generated Nonradiolabeled Probe

Journal of Veterinary Diagnostic Investigation ◽

10.1177/104063879300500205 ◽

1993 ◽

Vol 5 (2) ◽

pp. 166-173 ◽

Cited By ~ 7

Author(s):

A. Akin ◽

C. C. Wu ◽

T. L. Lin ◽

R. W. Keirs

Keyword(s):

Disease Virus ◽

Infectious Bursal Disease Virus ◽

Salmonella Enteritidis ◽

Blot Hybridization ◽

Infectious Bursal Disease ◽

Slot Blot ◽

Slot Blot Hybridization ◽

Bursal Disease ◽

Serotype 1 ◽

Labeled Probe

A polymerase chain reaction (PCR)-generated digoxigenin-labeled nonradioactive oligonucleotide probe was developed and utilized in slot-blot hybridization coupled with chemiluminescence for the detection of infectious bursal disease virus (IBDV). The probe was prepared from the RNA of the standard challenge strain (STC) of IBDV serotype 1 by reverse transcription followed by 2 PCR amplifications with 2 separate sets of primers. RNA of STC viruses prepared from bursae infected with STC viruses was subjected to the first PCR with the outer primers V8 and V9 that amplified a 607-base pair (bp) segment. The PCR product from the first PCR was eluted following agarose gel electrophoresis and subjected to the second PCR with the nested primers V6 and V7 that flanked a 351-bp segment. In the second PCR, dTTP was substituted by digoxigenin-11-dUTP in the PCR reaction mixture so that the amplified 351-bp DNA products were labeled with digoxigenin. The specificity of the PCR-generated digoxigenin-labeled probe was tested on different strains of IBDV, several unrelated avian viruses, and bacteria by slot-blot hybridization assay. Hybridization was detected by chemiluminescence. The sensitivity of the probe was assayed using lo-fold serial dilutions of purified RNA from the STC strain of IBDV. The PCR-generated digoxigenin-labeled probe hybridized with genomic RNA of STC and variant strains A, D, E, G, and GLS-5 of IBDV serotype 1 but not OH strain of IBDV serotype 2. The probe did not react with avian reovirus, infectious bronchitis virus, Salmonella enteritidis, Escherichia coli, or Staphylococcus aureus. The probe was very sensitive, and as little as 72 fg of RNA from the STC strain of IBDV could be detected. The results indicate that this PCR-generated digoxigenin-labeled nonisotopic probe is specific for IBDV and may be utilized in a diagnostic assay for all IBDV serotype 1 strains.

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