A Microscopic and Molecular Investigation into the Prevalence of Giardia duodenalis in Stray Dogs in the Bitlis Province
Prevalence of Giardia duodenalis in Stray Dogs
DOI:
https://doi.org/10.1071/ejmbs.v6i1.72Keywords:
Age, Assemblage, β-giardin, Nested PCR, PrevalenceAbstract
Giardia duodenalis is a globally distributed flagellated protozoan parasite infecting the gastrointestinal tract of humans, domestic animals, and wildlife. In dogs, infections are mainly associated with host-adapted assemblages C and D; however, the detection of zoonotic assemblages A and B in canine populations raises concerns regarding their possible role in the epidemiology of human giardiasis. Stray dogs may be particularly important in transmission dynamics because of their continuous exposure to contaminated environments and their potential to disseminate cysts in public areas. This study investigated the prevalence and molecular characteristics of G. duodenalis in 100 stray dogs from Bitlis Province, Türkiye, using microscopic examination and nested PCR targeting the β-giardin gene. Giardia cysts were detected by the native method in 3.0% (3/100) of samples, whereas nested PCR detected G. duodenalis DNA in 5.0% (5/100) of samples, indicating a higher detection rate with molecular analysis. No statistically significant association was found between infection status and sex (p = 1.000) or age group (p = 0.386), although positivity was numerically higher in dogs aged 0–1 month. Sequence analysis of the five PCR-positive samples revealed assemblage B in two isolates, assemblage C in two isolates, and assemblage D in one isolate, with 99.54–100% similarity to GenBank reference sequences. The detection of zoonotic assemblage B, together with dog-adapted assemblages C and D, suggests that stray dogs in Bitlis may have both veterinary and public health significance from a One Health perspective.
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