Abstract
Background:
Neospora caninum is one of the protozoa that have been identified in recent decades and plays an important role in causing disease in cattle, leading to abortions in pregnant animals. Therefore, to highlight the epidemiology of this parasite and the extent of genetic changes in local strains, this study was conducted.

Aim:
The goal of the present study is to find out the infection of Neospora caninum, the commonly causing abortion in cattle in the Iraqi region of Al-Diwaniyah.

Methods:
Two hundred samples were collected from slaughterhouses and butcher shops. Indirect Enzyme-linked immunosorbent assay (ELISA) antibodies had become used to perform the serological test involving the identification of N. caninum antibodies in 200 sera samples. Throughout the course of our study, 400 tissue samples divided into 200 samples each from the brain and muscles were gathered for genetic analyses using a primer set specific to the N. caninum gene via polymerase chain reaction.

Results:
The overall seroprevalence rate of N. caninum in analyzed serum samples was 7.5%. The prevalence rates were 17.5% in females and 5% in males. Also, the rates were 8.57% in 2-6 years of age category and 15.62% in spring. The molecular investigations revealed that the prevalence rate of N. caninum in tissue samples was 6%. The serological and molecular approaches showed 75% and 96.8% sensitivity and specificity. Sequencing and phylogenetic analysis showed that the N. caninum of local isolates is closely related to the global isolates from China, Poland, Australia, Palestine, Brazil, the USA, and Tunisia.

Conclusions:
According to serological results, the infection rate was not significantly related to age and season (p>0.05) but was significantly related to sex (p<0.01). The results of the two methods confirmed that the serological and molecular approaches exhibited an almost quite similar prevalence of N. caninum within tested samples. The present findings support an approach that is more economical, quick, repeatable, and efficient for determining the incidence and prevalence of N. caninum within herd populations during endemic or epidemic conditions.

Key words: ELISA, Neospora caninum, PCR, Serum, Tissue