Tissue reactions and physiological changes with genetic characterization of Giardia intestinalis infection in cattle...

Giardia intestinalis is a common protozoan parasite affecting both humans and animals. In livestock, infections can impact growth and productivity. To characterize Giardia infections in diarrheal cattle and assess associated physiological and genetic changes. One hundred calves (80 males, 20 females) from Faiyum Governorate were examined. Fecal and blood samples were analyzed for Giardia detection, oxidative stress markers, and immune gene expression. The TPI gene was sequenced for genetic characterization. In this study, 80 males and 20 females from a severely diarrheal cattle herd from the Faiyum Governorate were examined between January 2022 and May 2022 in order to characterize intestinal protozoa that caused severe diarrhea in cattle herds and determine their impact on physiological and immunological parameters. The blood of the infected animals was analyzed for oxidative stress and the infected intestine was examined for gene expression analysis to evaluate the cell-mediated appraisal. Fecal examination of severe diarrheic cattle revealed the presence of Giardia (G. intestinalis) trophozoites in 15 (15%) of 100 cattle analyzed. A microscopic examination of diarrheic-stained fecal smears with Giemsa revealed the presence of G. intestinalis. The TPI gene of the present parasite recognized morphologically as G. intestinalis was positively amplified using the pairs primers of the nested PCR. The PCR product was then directly sequenced and generated 505 bp. With the accession number OP441058, this sequence was added to the GenBank database. Giardia intestinalis causes significant physiological and immunological changes in calves, necessitating early detection and control.