Microscopic and Molecular Prevalence of Giardia duodenalis in diarrheic pet dogs

Abstract

This study was aimed to microscopically and molecularly identification the prevalence rate of Giardia duodenalis in diarrheic pet dogs with evaluation the associated risk factors. Fresh fecal samples were collected from 79 diarrheic dogs, and used to preparation the slide smears stained with Giemsa, and to extraction the DNAs that tested molecularly by the conventional polymerase chain reaction (PCR) assay through targeting the 18S rRNA gene. Our findings revealed that 2.53% and 29.11% of study dogs were positive to G. duodenalis using the light microscopy and PCR assay, respectively. In relation to risk factors, the positive results by microscopy and molecular assay were distributed significantly among the groups of age and sex factors. Regarding age factor, prevalence rate of G. duodenalis was increased significantly in dogs aged ≤4 months using of microscopy (7.69%) and molecular assay (53.85%) when compared to results of both assay in other age groups; 5-11 months (0% and 18.42%), and ≥12 months (0% and 13.33%). Concerning sex factor, the results of females and males were showed no significant differences between the values of both microscopy (3.45% and 0%), and molecular assay (29.31% and 28.57%). In conclusion, this study confirmed the effectiveness of molecular PCR assay in diagnosis of G. duodenalis infection suggesting that biomolecular methods are of great importance in clinical and epidemiological surveys. In addition, molecular classification tools are important to understand the pathogenesis and host range of Giardia isolates derived from a variety of animals. The significance of Giardia infection in dogs warrants further investigation, particularly with regard to production loss.