Detection of the bovine viral diarrhoea virus (BVDV) in young beef cattle in eastern and south-eastern regions of Poland

Is contamination of bovine-sourced material with bovine viral diarrhea virus still a problem in countries with ongoing eradication campaigns?

In this report, we describe the detection of bovine viral diarrhea virus (BVDV) contamination in commercial animal-derived sera and vaccines against animal viral pathogens on the market in Poland. Antibodies against BVDV were detected in 4/45 sera samples (8.9%) using an ELISA test. The presence of BVDV antigen was found using ELISA in 3/45 serum samples (6.6%) and 18/172 vaccine samples (10.5%). An RT -PCR was conducted using primers targeting two genome regions, the five prime untranslated region (5’UTR) and N-terminal protease (Npro). BVDV RNA was detected in 33/45 (73.3%) of sera, and 11/172 samples (6.4%) of collected vaccines, of which one vaccine did not declare BVDV strain in its composition. A single serum showed the presence of an infectious virus and only one was contaminated with all 3 species of BVDV. The most frequent species in sera was BVDV-3 (75.5%), whereas in vaccines only BVDV-1 was identified. Sequence analysis showed that the tested commercial sera and one vaccine were contaminated by six genotypes of BVDV: -1a, -1b, -1c, -1d, -2a, and -3. Identification of BVDV and its genetic material in animal-derived products is important due to the possibility of pestivirus transmission as well as the chance of falsifying the results of a diagnostic test. It also demonstrates the necessity of rigorous monitoring of the bioproducts used at the laboratory and industry level.

Occurrence of BVDV Infection and the Presence of Potential Risk Factors in Dairy Cattle Herds in Poland

Simple Summary

The bovine viral diarrhea virus (BVDV) causes one of the most common and economically important viral diseases of cattle. It affected cattle reproductive disorders in breeding cattle as well as decreased productivity through increased forced culling, morbidity, and mortality, all of which can be observed on the herd level. The aim of our study was the estimation of the occurrence of BVDV infection in different regions of Poland and the analysis of the different factors that could be correlated with the productive results. We evaluated 354 cattle herds. The presence of antibodies against the BVD virus was found in 33.3% of examined herds, and the heterogenous distribution of BVDV-positive herds in all regions of Poland was confirmed. We found that the rate of BVDV infection was strongly correlated with the geographical location of the examined cattle populations in Poland, the grazing of the animals, and the purchasing of new animals to be introduced to herds.

Abstract

The aim of the study was to analyze the risk factors of BVDV infection, in different regions of Poland, with respect to certain parameters of animal health, including productivity, herd management practices, the presence of BVDV, and the effect of non-vaccination. A total of 354 cattle herds were estimated and linked to the analysis of the different factors that might be correlated with productive results. The presence of antibodies against BVDV was found in 33.3% of examined herds, and the heterogenous distribution of BVDV-positive herds in all regions of Poland (p = 0.001) was confirmed. We found statistical correlations between BVDV infection and pasture (p = 0.004) and the number of grazing animals (p < 0.001), and also the purchase of animals for replacement (p = 0.004) was observed. Production or clear clinical outcomes potentially linked to BVDV infection in the herd have not been observed. The results of this study indicate that the rate of BVDV infection was most strongly correlated with the geographical location of the examined cattle populations in Poland. The second most significant factors were the grazing of animals and the purchasing of new animals to be introduced to herds. The strengthened procedures of management, as well as the implementation of eradication programs, should be considered in the examined herds.

Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): bovine viral diarrhoea (BVD)

Bovine viral diarrhoea (BVD) has been assessed according to the criteria of the Animal Health Law (AHL), in particular criteria of Article 7 on disease profile and impacts, Article 5 on the eligibility of BVD to be listed, Article 9 for the categorisation of BVD according to disease prevention and control rules as in Annex IV and Article 8 on the list of animal species related to BVD. The assessment has been performed following a methodology composed of information collection and compilation, expert judgement on each criterion at individual and, if no consensus was reached before, also at collective level. The output is composed of the categorical answer, and for the questions where no consensus was reached, the different supporting views are reported. Details on the methodology used for this assessment are explained in a separate opinion. According to the assessment performed, BVD can be considered eligible to be listed for Union intervention as laid down in Article 5(3) of the AHL. The disease would comply with the criteria as in Sections 4 and 5 of Annex IV of the AHL, for the application of the disease prevention and control rules referred to in points (d) and (e) of Article 9(1). The assessment here performed on compliance with the criteria as in Section 3 of Annex IV referred to in point (c) of Article 9(1) is inconclusive. The animal species to be listed for BVD according to Article 8(3) criteria are mainly species of the families Bovidae, Cervidae and Camelidae as susceptible species and several mammalian species as reservoirs.