Seroprevalence of Bovine Anaplasmosis Caused by Anaplasma marginale in Malaysia
1Samantha Pong, 2Nik Ahmad Irwan Izzauddin Nik Him
1School of Biological Sciences, Universiti Sains Malaysia Penang 11800, Malaysia. Corresponding Author: [email protected]
Anaplasmosis, also known as yellow fever, is an infectious parasitic disease of cattle caused by the protozoan Anaplasma marginale. Anaplasma marginale infects the erythrocytes and causes severe anaemia, weakness, loss of appetite, fever, depression, abortion, dyecreased milk production, constipation, jaundice and sometimes death. In Malaysia, data on A. marginale infection is still behind compared to other parasites such as nematodes. Anaplasmosis in livestock has received little attention in Malaysia with only occasional reports in cattle. In addition, the determinants of tick- and fly-borne transmission are not well understood. Looking into this possibility, this study was carried out to investigate and to compare the prevalence rate of bovine anaplasmosis in Malaysia. A seroprevalence study on bovine anaplasmosis was conducted at the Veterinary Research Institute, Malaysia. Sera of various cattle breeds were collected from farms and abattoirs to be tested for the presence of A. marginale. Competitive enzyme-linked immunosorbent assay (c-ELISA) Anaplasma antibody test kits by VMRD, Inc. were used for this study, where antibodies to A. marginale from sample sera inhibit the binding of horseradish peroxidase (HRP)-labelled monoclonal antibody to the Anaplasma antigen coated on the plastic wells. A total number of 267 serum samples were tested and 79.4% were positive for bovine anaplasmosis. Results showed that the infection percentage is 100% in Pahang while the state with lowest infection percentage is Sabah with 59.2%. A comparison is done between Peninsular Malaysia with Sabah and Sarawak. The infection percentage in Peninsular Malaysia is higher at 87% while Sabah and Sarawak has an infection percentage of 60%. However, there is no significant difference in the rate of infections. The high number of cases in Peninsular Malaysia may be caused by the lack of strict control measures due to dependence on modern tools and drugs, while cases in Sabah and Sarawak may be due to traditional practices carried out frequently that may cause iatrogenic transmission. More samples should be obtained in order to validate the results. In addition, annual studies must be done to monitor the status of A. marginale prevalence in local cattle that is medically and economically significant to Malaysia.
Keywords: Anaplasma marginale, bovine, disease, anaplasmosis.