First report of Mycoplasma bovis infection in dairy cattle in Guangzhou, subtropical southern China

Mycoplasma bovis is a major bacterial pathogen causing mastitis in dairy cattle, pneumonia and arthritis, and reduced weight gain in calves and reproductive problems in both dairy cattle and bulls, resulting in significant economic losses. The objective of the present investigation was to examine the M. bovis seroprevalence in dairy cattle in Guangzhou, subtropical Southern China by using an enzyme-linked immunosorbent assay (ELISA). A total of 370 serum samples of dairy cattle were collected between July, 2009 and March, 2010 from 5 different farms and examined for M. bovis antibodies using a commercially available ELISA kit. The overall seroprevalence of M. bovis infection in dairy cattle was 5.95% (22/370). One year-old dairy cattle had the highest seroprevalence (10.5%), followed by dairy cattle of 3 year-old (9.61%). Dairy cattle without pregnancy had the highest seroprevalence (9.26%), followed by dairy cattle with 2 pregnancies (8.62%). However, no statistically significant association was found between M. bovis infection and ages or numbers of pregnancies (P>0.05). These results indicate that M. bovis infection was present in dairy cattle in Guangzhou, subtropical Southern China, and integrated strategies and measures should be executed to control and prevent M. bovis infection and disease outbreak in the study region.   Key words: Mycoplasma bovis, seroprevalence, dairy cattle, China, enzyme-linked immunosorbent assay (ELISA).