Seroprevalence of enzootic bovine leukosis in Trakya district (Marmara region) in Turkey.

In this study, 481 cattle belonging to 77 farms from nine localities in Trakya district in the Marmara region of Turkey were blood sampled and serologically tested for enzootic bovine leukosis (EBL). Antibodies to bovine leukosis virus (BLV) were detected in 51 cattle sera (11%) belonging to nine farms in five localities. Cattle tested were mostly female Holstein or Brown Swiss of ages ranging between 18 months and 10 years. Analysis of the relationships between age, breed or sex and seropositivity to EBL in seropositive herds indicated no significant associations (p > 0.05). The relationship between seropositivity and haematological changes was also studied, and seropositive cattle had higher lymphocyte percentage and lower neutrophil percentage than seronegative cattle (p < 0.001).