Molecular epidemiology and risk factors associated with Babesia bigemina infection in cattle.

Bovine babesiosis caused by Babesia bigemina is an important tick-borne disease that affects cattle health and productivity in tropical and subtropical regions. The present study aimed to determine the prevalence of B. bigemina in cattle and to identify associated risk factors in three governorates of the Nile Delta region, Egypt. A total of 400 blood samples were collected randomly from cattle and examined using nested PCR assay. The overall prevalence of B. bigemina prevalence was 8% (32/400). The prevalence did not differ significantly according to locality or sex (P > 0.05). However, significant variations were observed in relation to breed, age, season, tick infestation, and management practices. Mixed-breed cattle showed the highest prevalence (11.4%), followed by Friesian (5.2%) and native breeds (1.8%). Older animals (> 4 years) exhibited the highest infection rate (24%). Seasonal variation indicated that the highest prevalence occurred during summer (13.6%). Management-related factors also influenced infection rates; cattle receiving regular antiprotozoal treatment had a lower prevalence (2.4%) compared with untreated animals (11%). Tick-infested cattle showed higher infection rates (9.8%) compared with non-infested animals (3.5%), while the absence of acaricide application was associated with increased infection risk. Multivariable logistic regression analysis identified mixed breed OR = 6.96; 95% CI: 2.08-60.48), age over 4 years (OR = 7.01; 95% CI: 2.07-23.73), summer season (OR = 4.16; 95% CI: 1.10-15.71), lack of antiprotozoal drug use (OR = 6.04; 95% CI: 1.28-28.44), tick infestation (OR = 3.16; 95% CI: 1.09-10.23), and absence of acaricide application (OR = 2.37; 95% CI: 1.28-6.32) as significant predictors of infection. These findings highlight the important role of vector control and proper management practices in reducing the burden of bovine babesiosis. Continuous surveillance and integrated tick control strategies are essential for improving cattle health and productivity in endemic areas.