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Porcine Reproductive and Respiratory Syndrome (view source)
Revision as of 16:10, 27 August 2010
, 16:10, 27 August 2010→Control
==Control==
==Control==
Currently, there are no effective treatment programs for acute PRRS. Attempts to reduce fever using NSAID (aspirin) or appetite stimulants (B vitamins) appear to have minimal benefit. The use of antibiotics or autogenous bacterins to reduce the effects of opportunistic bacterial pathogens have also been reported; however, results have been mixed.
Prevention of infection appears to be the primary means of control. Understanding the PRRS status of replacement gilts and boars, as well as proper isolation and acclimatization of incoming stock are critical measures to prevent viral introduction. Pigs should be retested on arrival at the isolation facility and 45-60 days later, before entry to the herd. Elimination of existing infection by multisite production and segregated early weaning has also been described. While these strategies have had some success, the longterm risks of reinfection appear high. Prevention of viral spread by nursery depopulation has been described. This is successful when virus transmission is not occurring in the sow herd (usually 12-18 mo after initial outbreak), but the nurseries and growing/finishing pigs are still infected. All nursery pigs are removed from the farm to be finished elsewhere. The nurseries are then aggressively washed and disinfected and left empty for 7-14 days, after which they can be used normally. The technique has successfully eliminated PRRS virus from several herds, in which pigs have remained seronegative (for >1 yr) to market age, and production in the nurseries has improved, both in growth rate and mortality.
Commercial vaccines, both modified live and killed, have been licensed and have been effective in controlling outbreaks and preventing economic losses.
Recently, eradication of PRRS has been demonstrated to be possible on an individual farm basis. Methods such as whole herd depopulation-repopulation, test and removal, and herd closure have been documented as effective methods for eliminating PRRS virus from endemically infected herds. Unfortunately, a number of eradication efforts have failed due to the introduction of new isolates through unidentifiable routes.
==Prognosis==
==Prognosis==