Bluetongue virus seroprevalence and risk factor analysis in cattle and water buffalo in southern Italy (Campania region)

Abstract

Bluetongue is an arthropod-borne viral infection that is notifiable in several countries and causes significant economic losses and major concerns for ruminant trade. In this study, we investigated bluetongue 1seroprevalence in the Campania region, southern Italy, in cattle and buffalo populations, and assessed which factors were correlated with a high risk of exposure. The infection was widespread, as evidenced by the high individual (43.6%) and herd prevalence (85.4%). The highest prevalence was found in adult animals. Among the climatic factors analyzed, average temperature played a prominent role, being capable of affecting the probability of being positive for this infection. Surprisingly, exposure to Schmallenberg virus did not predispose animals to be positive for bluetongue virus, even though these infections share the same vector (Culicoides). Our data, consistent with those in the literature, suggest the transversal spread of bluetongue virus in the Mediterranean area, and indicate a limited co-exposure rate between Bluetongue and Schmallenberg viruses.

Pigs in southern Italy are exposed to three ruminant pathogens: an analysis of seroprevalence and risk factors analysis study

“…The first aspect could be explained by the climatic characteristics of the above-mentioned provinces, which have a milder climate than the other locations belonging to internal areas. In fact, average temperature and the proximity to the coast favor the activity of the vector and, therefore, the spread of SBV and the possibility of it being transmitted to pigs [ 19 , 20 ]. The second aspect (age), however, is explained by the fact that boars and sows have a greater chance of being seropositive as they experience multiple vector seasons.…”

“…This area has a Mediterranean climate, which allows the epidemiologic cycle of viruses transmitted by vectors ( Culex , Culicoides , etc.) [ 19 , 20 ]. The largest type of farming involves ruminants (mainly buffalo), while pig farming counted 75,000 animals at the time of sampling (2% of the national total; Banca Dati Nazionale dell’ Anagrafe Zootecnica, https://www.vetinfo.it/j6statistiche/ , accessed November 15, 2022).…”

“…The detection of antibodies against BVDV and SBV was further confirmed by subjecting the same samples to a virus neutralization assay. In both cases, protocols described in the literature were used, cultivating MDBK and BHK-21 cells in 96-well plates, susceptible to BVDV and SBV, respectively [ 19 , 22 , 23 ]. Serial serum dilutions from 1:2 to 1:256 (inactivated at 56 °C for 30 min) were mixed with 100 TCID50 of BVDV strain NADL (ATCC) and 500 TCID50 of SBV strain BH80/11–4 (gently provided by “Friedrich-Loefer-Institut”, Germany and “Istituto Zooproflattico Sperimentale dell’Abruzzo e del Molise G. Caporale”, Italy).…”

Efficiency of recombinant Ybgf in a double antigen-ELISA for the detection of Coxiella antibodies in ruminants

“…These settings were chosen by testing different amounts of coated antigen (8, 25, and 50 ng), HRP-conjugated Ybgf (not diluted, 1:2 and 1:4), and serum dilutions (1:2, 1:4, 1:8) of positive and negative control sera (crisscross serial-dilution of an initial panel of sera consisting of 6 negative and 6 positive cattle) ( Ferrara et al, 2023a ). A panel of apparently healthy ruminant sera belonging to other studies (280 goats and 234 cattle) was randomly chosen to investigate the potential of double-Ybgf ELISA against a commercial one (Q fever Ab test kit; Idexx) ( Ferrara et al, 2022a , 2023b , 2023c ). The commercial indirect ELISA was performed following the manufacturer's instructions.…”