Leptospirosis control on an intensive raising pig farm

Abstract

Leptospirosis is an infective disease which represents serious health and economic problems in pig raising. The disease is caused by bacteria from genus Leptospira interrogans, which has over 250 serotypes and is isolated from most animal species and also from humans in almost every country in the world. In farm conditions the disease is seldom manifested as a clinically apparent illness. More often is manifested as reduced conception rate increased abortion rate and increased birth of dead and non-vital piglets. The leptospirosis control and eradication program was made for a state owned farm with a capacity of about 1500 sows and over 30000 fattened animals per year. The farm had an on going endemic leptospirosis infection and subsequent progressive economic losses. We detected 29,80% seropositive sows and gilts in which serotypes pomona and icterhaemorrhagiae were isolated. Serologic examination of blood was performed again after program implementation, and no positive animals were found, while production and economic results were improved. The control of leptospirosis and the eradication program for a five-year period were based on detailed quantification of economics losses. Using cost-benefit analysis the necessary inputs and planned outputs were defined, and program evolution was made on the basis of net present value and benefit/cost ratio.

Leptospiroza svinja kao infektivna bolest dovodi do ozbiljnih zdravstvenih i ekonomskiih problema u razvoju svinjarstva. Bolest izaziva bakterija iz roda Leptospira koja ima preko 250 serotipova i dijagnostikovana je kod većeg broja životinja i ljudi u skoro svim zemljama sveta. Pojava bolesti na farmi se retko manifestuje u vidu jasno izraženih kliničkih simptoma, a znatno češće u vidu reproduktivnih poremećaja koji se ogledaju u smanjenoj koncepciji krmača i nazimica, povećavanju abortusa i rađanju mrtve i avitalne prasadi. Ispitivanja su izvršena na jednoj državnoj farmi kapaciteta oko 1 500 krmača i 30 000 tovljenika godišnje. Pregledom krvnih seruma krmača i nazimica ustanovljeno je prisustvo specifičnih antitela serotipa L. pomona i L. icterohaemorrhagiae kod 29,80% ispitivanih grla. Na osnovu detaljne analize ekonomskih šteta primenom cost-benefit analize urađen je program kontrole i eradikacije leptospiroze svinja za period od pet godina. Pri izradi programa definisani su potrebni inputi i autputi, a ocena programa izvršena je na osnovu neto sadašnje vrednosti i odnosa dobiti i troškova. Posle implementacije programa izvršen je serološki pregled krvi i nije utvrđeno ni jedno pozitivno grlo, a proizvodno ekonomski rezultati su značajno poboljšani.