Survey of Neospora caninum and bovine herpes virus 1 coinfection in cattle.

A seroprevalence survey of Neospora caninum and bovine herpesvirus 1 (BHV-1) was conducted in cattle pasturing in an area of the southern Italian Apennines to investigate the coinfection of these two pathogens. Blood samples were collected from 948 pastured cattle raised on 81 farms. Sera were tested for antibodies to N. caninum and to BHV-1 using an ELISA assay and a neutralization test, respectively. Out of the 81 farms sampled, 63 (77.8%) were positive for N. caninum and 80 (98.8%) for BHV-1. Coinfection was found in 62 (76.5%) farms. Out of the 948 bovine sera samples, 303 (32.0%) had antibodies to N. caninum and 735 (77.5%) to BHV-1. The copresence of antibodies to N. caninum and BHV-1 was found in 256 (27.0%) cattle. The logistic regression results indicated that seropositivity for BHV-1 was a risk factor for N. caninum seropositivity and seropositivity for N. caninum was a risk factor for BHV-1 seropositivity.