Giardia duodenalis infection frequently occurs in dogs and is predominantly attributed to assemblages C and D. The objective of this work was to evaluate the association between G. duodenalis occurrence, its different assemblages detected in both symptomatic and asymptomatic dogs, and the manifestation of specific clinical signs. All examined dogs (n = 82) underwent a clinical evaluation, and fecal specimens were analyzed for other intestinal parasites and Clostridium spp. In addition, G. duodenalis assemblages were identified, and certain clinical manifestations were recorded. Out of the 82 dogs, 42 (51.2%) exhibited one or more gastrointestinal symptoms, whereas 40 (48.8%) showed no symptoms. G. duodenalis was detected in 25/82 (30.5%) dogs, with assemblage C identified in 10/25 (40%) and assemblage D in 15/25 (60%). Among coinfections, only Cryptosporidium spp. Presented a higher concurrent rate with G. duodenalis, although it did not influence the presence of clinical signs. No relationship was established between the type of G. duodenalis assemblage and the sex of the host or the nature and duration of gastrointestinal symptoms, except for mucus in feces, which appeared more frequently in dogs infected with assemblage C. Additional studies are needed to explore other assemblages further.
