scholarly journals Clinical and histopathological studies on neurodegeneration and dysautonomia in buffalo calves during foot-and-mouth disease outbreaks in Egypt

2021 ◽  
pp. 1622-1630
Author(s):  
Yasmin Bayoumi ◽  
Nader Sobhy ◽  
Abdelkarem Morsi ◽  
Wafaa El-Neshwey ◽  
Nora El-Seddawy ◽  
...  

Background and Aim: Signs of dysautonomia were frequently observed in calves that died during foot-and-mouth disease (FMD) virus (FMDV) outbreaks in Egypt from 2015 to 2018. This study aimed to describe the clinical and histopathological features of the central nervous system in malignant cases of FMD and excluding possible concurrent bacterial, and bovine herpes virus 4 (BHV4) infections or both. Materials and Methods: In this study, 335 FMDV-infected buffalo calves aged 1-22 months were clinically examined and followed until recovery or death. Of the 335 calves, 134 died (malignant group) and 201 recovered after exhibiting classic symptoms of FMD (recover group). The calves were subjected to clinical examination. For the malignant group, several laboratory trials were conducted to assess the possible cause/s of dysautonomia-related viral, bacterial, or concurrent infections. Koch's postulates and polymerase chain reaction were employed. Postmortem and histopathological examinations of nervous tissue were performed. Results: In the malignant group, signs of dysautonomia were observed before death, including partial or complete gut dysfunction, loss of anal sphincter tone, rapid breathing sounds, fluctuating body temperature, and cardiac arrhythmias. In the malignant group, histopathological examination of the spinal cord, pons, medulla oblongata, hypothalamus, cerebellum, and cerebrum revealed demyelination, neuronal degeneration, and focal areas of malacia and gliosis. The nervous tissue and heart samples from malignant cases were positive for serotype O FMDV. Conclusion: Findings revealed in this study support the existence of neurodegeneration induced by FMDV infection in buffalo calves.

2021 ◽  
pp. 104914
Author(s):  
Zahra Naeem ◽  
Sohail Raza ◽  
Saba Afzal ◽  
Ali Ahmad Sheikh ◽  
Muhammad Muddassir Ali ◽  
...  

2015 ◽  
Vol 64 (3) ◽  
pp. 849-860 ◽  
Author(s):  
G. Govindaraj ◽  
B. Ganeshkumar ◽  
K. R. Nethrayini ◽  
R. Shalini ◽  
V. Balamurugan ◽  
...  

2014 ◽  
Vol 95 (5) ◽  
pp. 1104-1116 ◽  
Author(s):  
Amin S. Asfor ◽  
Sasmita Upadhyaya ◽  
Nick J. Knowles ◽  
Donald P. King ◽  
David J. Paton ◽  
...  

Five neutralizing antigenic sites have been described for serotype O foot-and-mouth disease viruses (FMDV) based on monoclonal antibody (mAb) escape mutant studies. However, a mutant virus selected to escape neutralization of mAb binding at all five sites was previously shown to confer complete cross-protection with the parental virus in guinea pig challenge studies, suggesting that amino acid residues outside the mAb binding sites contribute to antibody-mediated in vivo neutralization of FMDV. Comparison of the ability of bovine antisera to neutralize a panel of serotype O FMDV identified three novel putative sites at VP2-74, VP2-191 and VP3-85, where amino acid substitutions correlated with changes in sero-reactivity. The impact of these positions was tested using site-directed mutagenesis to effect substitutions at critical amino acid residues within an infectious copy of FMDV O1 Kaufbeuren (O1K). Recovered viruses containing additional mutations at VP2-74 and VP2-191 exhibited greater resistance to neutralization with both O1K guinea pig and O BFS bovine antisera than a virus that was engineered to include only mutations at the five known antigenic sites. The changes at VP2-74 and VP3-85 are adjacent to critical amino acids that define antigenic sites 2 and 4, respectively. However VP2-191 (17 Å away from VP2-72), located at the threefold axis and more distant from previously identified antigenic sites, exhibited the most profound effect. These findings extend our knowledge of the surface features of the FMDV capsid known to elicit neutralizing antibodies, and will improve our strategies for vaccine strain selection and rational vaccine design.


Vaccine ◽  
2017 ◽  
Vol 35 (51) ◽  
pp. 7147-7153 ◽  
Author(s):  
Mana Mahapatra ◽  
Sasmita Upadhyaya ◽  
Sharie Aviso ◽  
Aravindh Babu ◽  
Geoff Hutchings ◽  
...  

2018 ◽  
Vol 66 (1) ◽  
pp. 7-13 ◽  
Author(s):  
Giulia Pezzoni ◽  
Arianna Bregoli ◽  
Santina Grazioli ◽  
Ilaria Barbieri ◽  
Hafsa Madani ◽  
...  

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