Seroprevalence and risk factors for the presence of ruminant pestiviruses in the Dutch swine population

Abstract

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Serological Study on Bovine Viral Diarrhoea Virus Infection in Pig Population in Poland Between 2008 and 2011

“…Similar results, i.e. higher rate of BVDV seroprevalence in pigs on mixed farms, was also reported by Deng et al (19), and Tao et al (38). At that time, the presence of seroreagents was found in all provinces in which the samples were collected (29).…”

“…Studies on BVDV/BDV seroprevalence in swine are rare and mostly difficult to compare because of different sampling schemes, different age categories of tested animals, and different tests applied (19). Studies on seroprevalence of ruminant pestiviruses in wild boar were conducted in Germany (3,34), the USA (20), Croatia (31,44), and the Czech Republic (33) and revealed that the percentage of seropositive animals did not exceed 8%.…”

“…Finally, it should be emphasised that the low rate of BVDV infections observed in the Dutch and Polish swine populations is probably caused by continued specialisation of animal farms (19). In the past most farmers used to rear cattle, pigs, poultry, and other animals on the same premises.…”

“…A high homology rate between CSF and BVD viruses, interspecies crossing, and infection of pigs with BVDV could create a serious diagnostic problem (25,36,37,43). Cattle is considered as the main reservoir and source of BVDV for pigs (7,8,10,15,16,19,38,41). Lenihan and Collery (15) found that 27.8% BVDV antibody positive sows had contact with cattle, while 3.6% seropositive sows were without contact, and 4.5% of five-six months old pigs have had little or no contact with cattle.…”

“…According to De Smit et al (7,8) 59% of seropositive sows came from mixed farms (cattle and pigs on the same premises) or from farms where ruminants were kept in close vicinity of pig holding. Loeffen et al (19) evaluated several risk factors associated with the presence of swine and ruminants on the same farm or in close vicinity of pig holding. They found that sows on mixed farms had a 3.4 higher chance to have a BVDV-seropositive status than in the herds without cattle.…”