This cross-sectional study was conducted to determine the prevalence of canine giardiasis in selected veterinary clinics in Nueva Ecija including Cabanatuan City, Gapan City and San Jose City from August to September 2021 A total of 112 fecal samples were collected from dogs brought to the clinics for consultation of treatment. The samples were examined using direct microscopy and immunochromatographic assay. Direct microscopy revealed a prevalence of 55.36%, (62/112) while 34.8%, (39/112) were positive using immunochromatography. The prevalence is highest in age group of three to six months (65.62%) and lowest in group of one year to three years old (30.33%). Between sex, almost same percentage were infected in both male and female dogs at 56.14% and 54.54%, respectively. Among breeds with three entries, prevalence is highest in large breeds at 70% compared to medium breeds and small breeds at 65.22% and 47 07% Giardiasis is also more prevalent in dogs with no vaccination (73 33%), those that were not dewormed or deworming not updated at 66 66% and 63.63% respectively Co-infection with other pathogens either bacteria, parasitic, virus or combination was common and found at 62.9% of all cases. Several factors were found associated with Giardiasis in univariate analysis including age, breed, housing, water source, origin, but only three were confirmed as risk factors through multivariate logistic regression. The risk factors identified for giardiasis in this study are breed (OR:047 and 0.31), water source (OR:0.241) and origin (OR:0.392). As to agreement between the two tests used, microscopy and immunochromatography, there is a moderate strength of agreement between the two tests. Results of this study highlights the need for education and awareness campaign to promote responsible pet ownership practices, including regular veterinary visits, proper sanitation, and appropriate waste disposal. Further studies can be conducted to investigate the specific strains or subtypes of Giardia present in dogs and their potential zoonotic implications.

Thesis (Doctor of Veterinary Medicine)

includes appendices and bibliographical references.