Funding for this research was provided by:
Ministry of Higher Education
Centers for Disease Control and Prevention
Received: 9 March 2018
Accepted: 27 June 2018
First Online: 11 July 2018
Ethics approval and consent to participate
: Informed consent was obtained from the parents or guardians prior to specimen collection. The fieldwork was approved by the ethics committee of the Faculty of Veterinary Medicine, Mansoura University, Egypt.
: Not applicable.
: The authors declare that they have no competing interests.
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