Since its appearance in the late 1980’s and its identification in 1991, the majority of the pig producing countries have reported porcine reproductive and respiratory syndrome virus (PRRSV) infections and nowadays it is considered endemic in most of them. The disease in sows and gilts causes mild to severe reproductive problems, while in nursery and fattening pigs the typical signs of the disease are respiratory problems and increased mortality, resulting in reduction of average daily weight gain (ADG) and feed efficiency. However, in some cases a lack of clinical signs and/or poor recognition of them can cause that PRRSV infections remain undetected on positive herds.
The goal of this study was to obtain the perception of PRRSv prevalence by swine practitioners in different European countries.
MATERIALS AND METHODS
An Europe-wide survey was undertaken to assess PRRS prevalence in European pig production. 515 swine veterinary practitioners were interviewed in 11 countries across Europe between January and March of 2014 in relation to the presence of PRRS in the farms under their care. The distribution of pig producers interviewed is shown in table 1.
TABLE 1: NUMBER OF INTERVIEWED SWINE PRACTITIONERS.
Each practitioner was asked to estimate the percentage of the animals under his or her supervision that were PRRS-positive. In fact, the veterinarians could respond by saying if pigs were infected and showed clinical signs, or were infected without clinical signs, or were not infected with the virus.
RESULTS AND CONCLUSION
According to the interviewed practitioners, on average PRRS is present in 71 % of sows and in 68 % of weaned or growing pigs. While on average, clinical cases of the disease were estimated to occur in 17 % of sows and in 23 % of weaned or growing pigs. However, the incidence in sows in particular varied widely by country, from a high of 47 % reported from Italy to just 4 % for Russia.
TABLE 2: REPORTED PREVALENCE OF PRRS BY COUNTRY IN SOWS OR NURSERY AND FATTENING PIGS
The survey demonstrates a wide variation between countries, but also a clear general indication that most pigs in Europe are PRRS- positive: the virus remains highly prevalent in sows as well as in pigs from the nursery to the finishing pen.
What is more, the replies of the veterinarians suggest that a considerable proportion of pigs in Europe are not only infected, but also clinically affected by PRRS. This information underlines the need for European pig herds to stay vigilant against PRRS virus.