STRATEGIES TO CONTROL PRRS - A SUMMARY OF FIELD AND RESEARCH EXPERIENCES

Various methods for the control of PRRS virus have been published. The technology of nursery depopulation (ND) appears to effectively contro l the spread of virus between members of endemically infected populati ons. ND consists of a strategic adjustment in pigflow based on the pre sence of specific serologic patterns as detected by the indirect fluor escent antibody test. This pattern indicates a low seroprevalence of a ntibodies detected in the breeding herd and recently weaned piglets (l ess than or equal to 10%), in contrast to a high (>50%) seroprevalence in 8 to 10 week old piglets. ND has been carried out on swine farms i n the US and results indicate improvements in nursery piglet growth ra te and mortality levels. Three examples are provided in the following text. Recently a modified live virus vaccine (RespPRRS, NOBL Laborator ies/Boerhinger Ingleheim) has become commercially available. It is cur rently approved for use in piglets from 3 to 18 weeks of age; however, potential for the use in adult animals is currently under investigati on. (C) 1997 Elsevier Science B.V.