Natural infection of calves by Anaplasma marginale in dairy herds of the Metalúrgica Region, Minas Gerais

Pesquisa Veterinária Brasileira

Valeska S.p. Melo²  Lygia M.f. Passos²  Elias J. Facury-filho²  Helton M. Saturnino²  Múcio F.b. Ribeiro¹ 

[1] ,Universidade Federal de Minas Gerais Escola de Veterinária Belo Horizonte MG

关键词: Anaplasma marginale;    anaplasmosis;    cattle;    epidemiology;    Anaplasma marginale;    anaplasmose;    bovinos;    epidemiologia;   

DOI  :  10.1590/S0100-736X2001000400004

来源: SciELO

【 摘 要 】

The dynamic of natural infections by Anaplasma marginale in calves was evaluated during a period of one year on two farms located in the Metalúrgica Region, State of Minas Gerais, Brazil. Blood samples were collected weekly for rickettsemia and packed cell volume (PCV) determination. The animals born from March to July suffered the infection in October and November, independently of their age, whilst calves born from September to December acquired the infection during the first days of life. These animals presented patent rickettsemia from 30 days of life. During the patent period PCV decreased after one week of infection, ranging from 20 to 23%. It was concluded, that in the region studied, the transmission of A. marginale is influenced by climatic conditions, and that calves born during the dry season are more likely to acquire the infection when they are exposed to high transmission levels during the subsequent raining season.

【 授权许可】

CC BY-NC   
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