Prevalence of Giardia in dairy cattle in Lusaka and Chilanga districts, Zambia.

Abstract Giardia is an intestinal protozoan parasite of mammals including humans. A cross-sectional study was conducted to estimate prevalence of Giardia infections in smallholder and commercial dairy herds in Chilanga and Lusaka districts of Zambia. A total of 377 calves aged from 1 to 365 days were sampled on 34 farms. All faecal samples were analyzed for Giardia antigen using a commercially available ELISA kit. Overall prevalence of Giardia was 34.5% (95% CI = 29.7–39.3). Among smallholder farms, animal level prevalence ranged from 0 to 100% (mean = 44.6 ± 36.9 standard deviations) and 12.5 to 60.9% (mean = 33.5 ± 16.7 standard deviations) within commercial herds. Prevalence was highest in calves less than three months old ( p  = 0.010), and there was no significant difference in the prevalence between smallholder and commercial farms ( p  = 0.300). Giardia prevalence was not associated with occurrence of diarrhoea in the calves ( p  = 0.205). The study demonstrates that Giardia infections are common in dairy herds in the study areas, especially in calves less than three months of age.