ABSTRACT
This molecular-epidemiological study was conducted in several locations in Cairo and Giza Governorates in domestic cats (Felis catus) to detect the most common intestinal helminths in feces and molecularly characterize this nematode. So, three hundred domestic cats were admitted to different clinics around Cairo and Giza Governorates with severe diarrhea, even watery, between January 2023 and April 2023. The ages of the cats ranged from 1 to 2.5 years old. Blood, sera, and urine samples were collected for further investigation of the health condition of the animals. Toxascaris leonina was the major intestinal parasite found in cat stools, with a prevalence rate of 5% (15 cats). Toxascaris leonina (T. leonina) eggs had oval elliptical surfaces and thick cuticles. An embryo was located inside the smooth outer shell wall of the shell. The animals suffer from normocytic normochromic anemia with leukocytosis, relative lymphocytosis, and thrombocytopenia. The amplification of the ITS-rDNA region from the ascaridoid nematodes was successfully performed using NC5 and NC2 primers. The PCR product of the ITS-rDNA fragment was sequenced and yielded 860 bp. The accession number of the sequenced ITS-rDNA region was OQ735413, submitted to Gene Bank, and based on the blast analysis of NCBI, the current ascaridoid nematode proved to be genetically related to the family Ascarididae and identified as T. leonina.