Assessment of Neospora caninum infection in bulls using serological and molecular techniques

Jamal Gharekhani; Rebin Rafaat Mohammed; Reza Heidari; Nasser Hajipour; Michele Trotta; Sergio Villanueva-Saz

doi:10.1016/j.vprsr.2023.100940

Assessment of Neospora caninum infection in bulls using serological and molecular techniques

Vet Parasitol Reg Stud Reports. 2023 Nov:46:100940. doi: 10.1016/j.vprsr.2023.100940. Epub 2023 Oct 14.

Authors

Jamal Gharekhani¹, Rebin Rafaat Mohammed², Reza Heidari³, Nasser Hajipour⁴, Michele Trotta⁵, Sergio Villanueva-Saz⁶

Affiliations

¹ Department of Laboratory Sciences, Central Veterinary Laboratory, Iranian Veterinary Organization, Hamedan, Iran. Electronic address: Gharekhani_76@yahoo.com.
² Department of Pathobiology, Faculty of Veterinary Medicine, Urmia University, Urmia, Iran; Director of the Central Clinical Laboratory of Sulaimani, Iraq.
³ Medical Biotechnology Research Center, AJA University of Medical Sciences, Tehran, Iran; Research Center for Cancer Screening and Epidemiology, AJA University of Medical Sciences, Tehran, Iran.
⁴ Department of Pathobiology, Faculty of Veterinary Medicine, University of Tabriz, Tabriz, Iran.
⁵ Clinical Immunology Laboratory, Veterinary Faculty, University of Zaragoza, Zaragoza, Spain.
⁶ Clinical Immunology Laboratory, Veterinary Faculty, University of Zaragoza, Zaragoza, Spain; Department of Animal Pathology, Veterinary Faculty, University of Zaragoza, Zaragoza, Spain; Instituto Agroalimentario de Aragón-IA2 (Universidad de Zaragoza-CITA), Zaragoza, Spain.

PMID: 37935541
DOI: 10.1016/j.vprsr.2023.100940

Abstract

Neospora caninum is a significant cause of abortion and economic losses in cattle worldwide. The main aim of the present work was to detect the prevalence of N. caninum infection in bulls in Hamedan (Iran) using serology and molecular techniques. All blood samples (n = 792) were screened for detecting the antibodies to N. caninum using enzyme-linked immunosorbent assay (ELISA). Then seropositive animals were rechecked using the immunofluorescent antibody test (IFAT). Also, blood, epididymis, and spinal cord samples were collected from animals for molecular analysis using nested PCR. In serology, using ELISA, 3.91% of animals were seropositive for N. caninum. Additionally, true prevalence based on the sensitivity and specificity of the ELISA was calculated 1.25% (95% CI: 0.48-2.02%). Neospora-infection in animals, calculated as the number of bulls seropositive and/or one sample positive to nested PCR, was 3.40%; and 19 bulls tested positive by both serology and molecular diagnostic methods. The overlaps between ELISA and molecular results were observed in 74.19% of whole blood samples, 80.64% of the epididymis, and 87.09% of the spinal cord. Using ELISA, the seroprevalence of N. caninum was detected 1.8% in ≤2 and 5.45% in >2 years old group of animals (p = 0.009, PR = 3.1). In addition, the seropositivity in Holstein and native breed animals was calculated 6.57% and 2.93%, respectively (p = 0.019, PR = 2.3). Seven sequences with 94.9-99.3% similarity were detected in multiple alignments of positive PCR products. Our work was the first comprehensive evaluation of Neospora-infection/neosporosis in Iranian bulls. We detected a low prevalence of infection in animals compared to previous reports. The ELISA is a sensitive serological technique for detecting the highest number of positive bulls in the present investigation and, the nested PCR is a reliable technique to identify Neospora-DNA.

Keywords: Bovine neosporosis; Laboratory diagnosis; Sequencing; Seroprevalence.

MeSH terms

Animals
Antibodies, Protozoan
Cattle
Cattle Diseases* / diagnosis
Cattle Diseases* / epidemiology
Coccidiosis* / diagnosis
Coccidiosis* / epidemiology
Coccidiosis* / veterinary
Female
Iran / epidemiology
Male
Neospora*
Pregnancy
Seroepidemiologic Studies

Substances

Antibodies, Protozoan