Experimental Neurology By Prof Paul Glees Pp xii + 532 (Oxford: Clarendon Press; London: Oxford University Press, 1961) 75s net

The Nervous System

VERY few veterinary surgeons have thought fit to write a book on diseases of poultry. Mr. Ernest Gray has done justice to the subject and is to be congratulated on his effort. A book of this size, written by one with specialized knowledge, will add to the value of any library or private bookshelf. Diseases of Poultry Their Aetiology, Diagnosis, Treatment and Control; with a Section on the Normal Anatomy and Physiology of the Fowl. By Ernest Gray. (Lockwood's Agricultural and Horticultural Handbooks.) Pp. x + 198 + 16 plates. (London: Crosby Lockwood and Son, Ltd., 1940.) 9s. 6d. net.

Diseases of Poultry

For over 30 years a phospholipase C enzyme called alpha-toxin was thought to be the key virulence factor in necrotic enteritis caused by Clostridium perfringens. However, using a gene knockout mutant we have recently shown that alpha-toxin is not essential for pathogenesis. We have now discovered a key virulence determinant. A novel toxin (NetB) was identified in a C. perfringens strain isolated from a chicken suffering from necrotic enteritis (NE). The toxin displayed limited amino acid sequence similarity to several pore forming toxins including beta-toxin from C. perfringens (38% identity) and alpha-toxin from Staphylococcus aureus (31% identity). NetB was only identified in C. perfringens type A strains isolated from chickens suffering NE. Both purified native NetB and recombinant NetB displayed cytotoxic activity against the chicken leghorn male hepatoma cell line LMH; inducing cell rounding and lysis. To determine the role of NetB in NE a netB mutant of a virulent C. perfringens chicken isolate was constructed by homologous recombination, and its virulence assessed in a chicken disease model. The netB mutant was unable to cause disease whereas the wild-type parent strain and the netB mutant complemented with a wild-type netB gene caused significant levels of NE. These data show unequivocally that in this isolate a functional NetB toxin is critical for the ability of C. perfringens to cause NE in chickens. This novel toxin is the first definitive virulence factor to be identified in avian C. perfringens strains capable of causing NE. Furthermore, the netB mutant is the first rationally attenuated strain obtained in an NE-causing isolate of C. perfringens; as such it has considerable vaccine potential.

/pdf/netb-a-new-toxin-that-is-associated-with-avian-necrotic-7iu9qoyskc.pdf

NetB, a New Toxin That Is Associated with Avian Necrotic Enteritis Caused by Clostridium perfringens

http://ssu.ac.ir/cms/fileadmin/user_upload/Mtahghighat/tfood/ARTICLES/microb-safety/Cross-contamination_and_recontamination_by_Salmonella_in_foods_A_review.pdf

Cross-contamination and recontamination by Salmonella in foods: A review

Phylogenetic network analysis and understanding of waterfowl migration patterns suggest that the Eurasian H5N8 clade 2.3.4.4 avian influenza virus emerged in late 2013 in China, spread in early 2014 to South Korea and Japan, and reached Siberia and Beringia by summer 2014 via migratory birds. Three genetically distinct subgroups emerged and subsequently spread along different flyways during fall 2014 into Europe, North America, and East Asia, respectively. All three subgroups reappeared in Japan, a wintering site for waterfowl from Eurasia and parts of North America.

/pdf/intercontinental-spread-of-asian-origin-h5n8-to-north-14h1n5r4mz.pdf

Intercontinental Spread of Asian-origin H5N8 to North America through Beringia by Migratory Birds

Novel Eurasian lineage avian influenza A(H5N8) virus has spread rapidly and globally since January 2014. In December 2014, H5N8 and reassortant H5N2 viruses were detected in wild birds in Washington, USA, and subsequently in backyard birds. When they infect commercial poultry, these highly pathogenic viruses pose substantial trade issues.

/pdf/novel-eurasian-highly-pathogenic-avian-influenza-a-h5-45w6rnswmh.pdf

Novel Eurasian highly pathogenic avian influenza A H5 viruses in wild birds, Washington, USA, 2014.

Population dynamics and antimicrobial resistance of the most prevalent poultry-associated Salmonella serotypes

Developmental, Metabolic, and Other Noninfectious Disorders

Campylobacter jejuni is a leading bacterial cause of human gastrointestinal disease worldwide. While C. jejuni is a commensal organism in chickens, case-studies have demonstrated a link between infection with C. jejuni and the consumption of foods that have been cross-contaminated with raw or undercooked poultry. We hypothesized that vaccination of chickens with C. jejuni surface-exposed colonization proteins (SECPs) would reduce the ability of C. jejuni to colonize chickens, thereby reducing the contamination of poultry products at the retail level and potentially providing a safer food product for consumers. To test our hypothesis, we injected chickens with recombinant C. jejuni peptides from CadF, FlaA, FlpA, CmeC, and a CadF-FlaA-FlpA fusion protein. Seven days following challenge, chickens were necropsied and cecal contents were serially diluted and plated to determine the number of C. jejuni per gram of material. The sera from the chickens were also analyzed to determine the concentration and specificity of antibodies reactive against the C. jejuni SECPs. Vaccination of chickens with the CadF, FlaA, and FlpA peptides resulted in a reduction in the number of C. jejuni in the ceca compared to the non-vaccinated C. jejuni-challenged group. The greatest reduction in C. jejuni colonization was observed in chickens injected with the FlaA, FlpA, or CadF-FlaA-FlpA fusion proteins. Vaccination of chickens with different SECPs resulted in the production of C. jejuni-specific IgY antibodies. In summary, we show that the vaccination of poultry with individual C. jejuni SECPs or a combination of SECPs provides protection of chickens from C. jejuni colonization.

/pdf/reducing-campylobacter-jejuni-colonization-of-poultry-via-4iweyjx782.pdf

Reducing Campylobacter jejuni Colonization of Poultry via Vaccination

Currently, the factors/toxins responsible for Clostridium perfringens-associated avian enteritis are not well understood. To assess whether specific C. perfringens' toxinotypes are associated with ...

https://journals.sagepub.com/doi/pdf/10.1177/104063870701900321

Rocio Crespo

Papers

Novel Eurasian highly pathogenic avian influenza A H5 viruses in wild birds, Washington, USA, 2014.

Population dynamics and antimicrobial resistance of the most prevalent poultry-associated Salmonella serotypes

Developmental, Metabolic, and Other Noninfectious Disorders

Reducing Campylobacter jejuni Colonization of Poultry via Vaccination

Toxinotypes of Clostridium Perfringens Isolated from Sick and Healthy Avian Species