Faculty of Veterinary Medicine University of Zagreb
Abstract
The prevalence rate of Trypanosoma brucei infection in pigs was appraised by a monoclonal antibody-based antigen-detection enzyme immunoassay (antigen-ELISA). Blood samples were collected in the abattoir from pigs reared in the rain forest and derived savannah region of Nigeria under the traditional extensive management system. Blood samples were also collected from 50 exotic pigs reared on a commercial farm with fly-proof pens. These blood samples were analyzed for presence of trypanosomes and antigens in peripheral blood. Of 189 porcine blood samples 51 (27.0%) were positive for circulating antigens, whereas only 4 (2.1%) had demonstrable trypanosomes as revealed by the haematocrit centrifugation/buffy-coat technique. When the 51 blood samples collected in EDTA tube corresponding to those sera that were positive for T. brucei antigens were subinoculated into mice, 46 (90.1%), the mice became infected. Demonstration of trypanosomes in the infected mice is supportive proof that the parasites were residing in the infected hosts. Samples collected from 50 exotic pigs in fly-proof pens were all antigen- ELISA negative. In addition, none of the corresponding 50 control blood samples had demonstrable trypanosomes by the buffy-coat method, nor do they show detectable parasites after subinoculation into mice. Thus, antigen-ELISA appeared to be a better and more useful tool for mass sero-epidemiological survey of porcine T. brucei infection when compared to the buffy-coat technique.Proširenost zaraze praživotinjom Trypanosoma brucei u svinja pretraživana je imunoenzimnim testom za dokaz antigena (antigen-ELISA). Uzorci krvi su prikupljeni u klaonici, od svinja uzgojenih u uvjetima tradicionalnog ekstenzivnog gospodarenja u području džungle i u području savane u Nigeriji. Uzorci su uzeti i od 50 egzotičnih svinja uzgojenih na komercijalnim farmama sa svinjcima zaštićenim od muha. Krvni uzorci su pregledani na prisutnost tripanosoma i na antigene u perifernoj krvi. Od 189 uzoraka krvi svinja, 51 (27,0%) je bio pozitivan na antigene u krvi, dok su samo u 4 (2,1%) otkrivene praživotinje tripanosome pomoću hematokrita. Kada su uzorci krvi od 51 svinje čiji su serumi bili pozitivni na praživotinju Trypanosoma brucei inokulirani miševima, 46 (90,1%) ih je postalo zaraženo. Nalaz tripanosoma u zaraženih miševa je dokaz da su paraziti živjeli u tim zaraženim svinjama. Uzorci od 50 egzotičnih svinja iz svinjaca bez muha su svi bili antigen- ELISA negativni. Uz to, niti jedan od tih 50 kontrolnih uzoraka nije pokazao prisutnost tripanosoma u sloju bijelih krvnih stanica, niti su pronađeni nametnici nakon inokulacije miševima. Tako se pokazalo da je antigen-ELISA bolja i korisnija metoda za masovne seroepidemiološke pretrage svinja na zarazu s praživotinjom T. brucei, u usporedbi s dokazom tripanosoma u bijelim krvnim stanicama
