Abstract
Sixty-eight case herds seropositive to porcine reproductive and respiratory syndrome (PRRS) were compared to 128 seronegative controls in a double-blinded questionnaire survey. The study indicated no increased risk of PRRS seropositivity for herds using artificial insemination with semen from PRRS seropositive AI-stations. Also the herd-size was non-related to the risk of PRRS seropositivity, indicating that air-borne spread of PRRS may not have been a predominant feature in Denmark. Introduction of replacement breeding animals from seropositive breeding- and multiplying herds significantly increased the risk of a herd being PRRS seropositive, as did introduction of 25 kg pigs for feeding. PRRS seropositivity was in the farmers' opinions associated with abortions in sows, early farrowing, high postweaning mortality and low weight gain in fattening pigs. However, the reported frequencies of problems were relatively low.
Keywords: Porcine reproductive and respiratory syndrome, PRRS, Risk
References
- Albina E., Leforban Y., Baron T., Plana Duran J., Vannier P. An enzyme linked immunosorbent assay (ELISA) for the detection of antibodies to the porcine reproductive and respiratory syndrome (PRRS) virus. Ann. Rech. Vet. 1992;23:167–176. [PubMed] [Google Scholar]
- Christensen L.S., Mousing J., Mortensen S., Sørensen K.J., Strandbygaard S.B., Henriksen C.A., Andersen J.B. Evidence of long-distance airborne transmission of Aujeszky's disease (Pseudorabies) virus. Vet. Rec. 1990;127:471–474. [PubMed] [Google Scholar]
- Flori J., Mousing J., Gardner I.A., Willeberg P., Have P. Risk factors associated with seropositivity to Porcine Respiratory Coronavirus in Danish swine herds. Prev. Vet. Med. 1995;25:51–65. [Google Scholar]
- Kleinbaum D.G., Kupper L.L., Morgenstern H. Van Nostrand Reinhold Company; New York: 1982. Epidemiologic Research. Principles and Quantitative Methods; pp. 67–70. [Google Scholar]; Kleinbaum D.G., Kupper L.L., Morgenstern H. Van Nostrand Reinhold Company; New York: 1982. Epidemiologic Research. Principles and Quantitative Methods; pp. 88–92. [Google Scholar]
- Denmark's Statistical Bureau. 1992. 1992. [Google Scholar]
- 4th Ed. Vol. 2. SAS Institute Inc; Cary, NC: 1989. pp. 1071–1126. (SAS/STAT® User's Guide). Version 6. [Google Scholar]
- Strøm J.S. Statens Byggeforskningsinstitut; Denmark: 1978. Heat loss from swine and poultry as basis for design of environmental control systems in livestock buildings; pp. 46–47. [Google Scholar]
- Willeberg P., Gardner I.A., Mortensen S., Mousing J. Models of herd size effects in swine diseases. Proc. of the 7th Int. Symp. on Veterinary Epidemiology and Economics; Nairobi, 15–19 August 1994; 1994. pp. 189–191. [Google Scholar]
- Yaeger M.J., Prieve T., Collins J., Christopher-Henning J., Nelson M.S., Benfield M. Evidence for the transmission of porcine reproductive and respiratory syndrome (PRRS) virus in boar semen. Swine Health Prod. 1993;5:7–9. [Google Scholar]