Research Summary - 3
From Serum to Milk, Cattle to Wildlife: A Comprehensive Evaluation of the ID ScreenŽ Neospora caninum Indirect and Competition ELISAs Across Species and Geographic Regions
| Date/Time: |
8/29/2026
10:45
|
| Author: |
Rafael Forero |
| Clinic: |
IDvet INC |
| City, State, ZIP: |
Hampton, NH 03842 |
R. Forero, DVM
1
;
J.Carlson, DVM, PhD
2
;
S. J.Wenzel, Dr Med Vet, PhD
2
;
P. Pourquier, MEng
2
;
1IDvet INC, Hampton, NH, 03842
2Innovative Diagnostics, Grabels, 34790, France
Introduction:
Neospora caninum is one of the most economically devastating infectious causes of reproductive failure in cattle worldwide. In the United States alone, annual losses attributable to neosporosis have been estimated at US $546 million in the dairy industry1, with North American cattle industries bearing approximately two-thirds of the global burden — estimated to exceed US $1.3 billion per year1. Seroprevalence in US dairy herds ranges from 16% to 36%, and up to 45% of aborted bovine fetuses have tested positive for the parasite2. With no effective vaccine or treatment, control depends on accurate diagnosis. IDvet offers two ELISAs: an indirect ELISA (iELISA) for ruminant serum, plasma, and milk, and a competitive ELISA (cELISA) for multi-species serum/plasma testing. This study evaluates their diagnostic performance and versatility.
Materials and methods:
iELISA – serum: diagnostic specificity was assessed on 163 negative samples; diagnostic sensitivity was evaluated on 200 positives. Cross-reactivity was tested with Toxoplasma gondii and Besnoitia spp.
Milk performance was evaluated on 239 negative and 117 positive samples, with 103 paired serum–milk samples for agreement.
cELISA performance was assessed on 1,046 negative and 315 positive sera across species. Agreement with iELISA (260 bovine sera) and IFAT were evaluated. A review of 25 publications (2019–2024) assessed field performance.
Results:
iELISA (serum) showed 100% specificity and sensitivity, with no cross-reactivity. Field studies confirm use across ruminants and buffalo.
In milk, iELISA reached 100% specificity and detected all positives (117/117), with good repeatability (CV ~8.1%). Serum–milk agreement was 92.2% (κ = 0.826).
cELISA showed 100% specificity and sensitivity. Agreement with iELISA was high (94.46%; κ = 0.875), with slightly higher sensitivity. Concordance with IFAT was 100%. Literature confirms use in ≥13 species across >10 countries, including livestock, pets, and wildlife.
Significance:
The iELISA provides excellent performance for serum and milk, supporting both individual diagnosis and herd surveillance. The cELISA combines high accuracy with broad multi-species applicability. Together, they offer a robust, flexible toolkit for Neospora caninum serology across species, matrices, and regions.
