RESUMO
Natural infection with Trichinella has been described in more than 150 mammalian species. However, few reports of Trichinella infection in wild animals have come from Argentina. In this study, muscle tissue was obtained from wild animals in Argentina with the aim of evaluating the presence of Trichinella. A total of 169 muscle samples were collected to determine the presence of Trichinella larvae by artificial digestion. The 169 muscle samples originated from 12 species including 36 opossums (Didelphis albiventris), 19 armadillos (Chaetophractus villosus), 9 capybaras (Hydrocaeris hydrocaeris), 1 puma (Puma concolor), 3 grey fox (Lycalopex gymnocercus), 6 coypus (Myocastor coypus), 6 skunks (Conepatus chinga), 2 ferrets (Galictis cuja), 66 rats (Rattus norvegicus), 6 mice (Mus musculus), 12 wild boars (Sus scrofa), and 3 wild cats (Felis geoffroyi). Trichinella infection was detected in 1 puma [2 larvae per gram (LPG)], 3 wild boars (8-420 LPG), 3 armadillos (0.04-0.08 LPG), and 9 rats (0.1 to 150 LPG). Only 3 Trichinella isolates, of 1 rat and 2 wild boars from Neuquén, were identified as Trichinella spiralis by nested PCR. The presence of Trichinella infection among wild animal populations suggests a sylvatic cycle of transmission in Argentina, which can serve as a reservoir for humans and domestic animals. Further, evidence of high prevalence in rats emphasizes the need to improve pig management, mainly in small individual farms without adequate technology, to enhance the quality of feeds, and to improve veterinary services to avoid exposure of pigs to Trichinella.
Assuntos
Animais Selvagens/parasitologia , Trichinella spiralis/isolamento & purificação , Triquinelose/veterinária , Animais , Argentina/epidemiologia , DNA de Helmintos/genética , Doenças Endêmicas , Músculos/parasitologia , Reação em Cadeia da Polimerase , Prevalência , Triquinelose/epidemiologia , Triquinelose/parasitologiaRESUMO
Recently, there has been interest in programs that certify pork production practices that minimize the risk of exposure of pigs to Trichinella spiralis. Certification might be useful for reducing the risk of human trichinellosis from pork in Argentina, but more information is needed on pig production practices and sources of Trichinella infection in Argentinian pigs. In this study, 21 pig farms were assessed for Trichinella infection including some farms using total and partial confinement management, and others with pigs raised exclusively outdoors. A total of 3224 muscle samples were collected from pigs raised on these farms and tested to determine the presence of T. spiralis larvae by artificial digestion. Serum samples from the same 3224 pigs were tested for antibodies to T. spiralis by ELISA. For each farm, a questionnaire was completed summarizing information about management factors and this information was used to assess risk factors for exposure of T. spiralis. Based on the results, pigs raised outdoors were more likely to be infected than pigs raised in total or partial confinement (p< or =0.05). Pigs fed waste products containing meat were 12.5 times more likely to be infected than pigs not fed waste containing meat (p<0.01). The role played by rats in transmission of Trichinella is unclear; however, on farms with evidence of wild animals and access of pigs to wildlife carcasses, the prevalence of Trichinella infection was significantly higher. All pigs raised under good hygienic and sanitary conditions were negative for Trichinella infection by both artificial digestion and ELISA.
Assuntos
Inspeção de Alimentos/normas , Parasitologia de Alimentos/normas , Carne/parasitologia , Triquinelose/transmissão , Animais , Argentina/epidemiologia , Ensaio de Imunoadsorção Enzimática/veterinária , Humanos , Ratos , Fatores de Risco , Controle de Roedores , Suínos , Doenças dos Suínos/epidemiologia , Doenças dos Suínos/parasitologia , Doenças dos Suínos/prevenção & controle , Triquinelose/prevenção & controle , Triquinelose/veterináriaRESUMO
The purpose of this work was to assess the clinical, haematological and biochemical responses of pigs experimentally inoculated with Trichinella spiralis. Groups of three pigs were inoculated per os with 100, 500 and 5000 T. spiralis muscle larvae, two pigs were used as control. Clinical evaluation of disease in pigs included daily examination, rectal temperature measurements and cardiac and respiration rates. Haematological studies included: hematocrit (%), hemoglobin (g/dl), and white cell, neutrophil, lymphocyte and eosinophil counts. Blood biochemistry included: bun (mg/dl), creatinine (mg/dl), AST (UI/l), ALT (UI/l), CPK (UI/l) and ALP (UI/l). No significant differences were observed in rectal temperature and in cardiac and respiration rates between inoculated animals and the control group (p> or =0.05). Significant differences were detected (p< or =0.05) in the values of % hemoglobin, and eosinophils, as well as in the values of CK, ALP, AST and ALT. The variations observed in some cases were related to the number of T. spiralis larvae inoculated and varied with the number of days post-infection. Inoculated pigs showed significant differences (p< or =0.05) in weight gain when compared with uninoculated controls. This study has clinical, haematological, and enzyme alterations in Trichinella infected pigs provides a better understanding of acute and chronic trichinellosis in pigs.
Assuntos
Doenças dos Suínos/parasitologia , Trichinella spiralis/isolamento & purificação , Triquinelose/veterinária , Envelhecimento , Animais , Creatina Quinase/metabolismo , Eosinófilos , Suínos , Doenças dos Suínos/economia , Doenças dos Suínos/patologia , Fatores de Tempo , Triquinelose/economia , Triquinelose/patologiaRESUMO
In Argentina, Trichinella infection in pigs is endemic. The first report of human trichinellosis in Argentina was from 1898 in Buenos Aires. The number of human cases increased from 908, between 1971 and 1981, to 6,919, between 1990 and 2002. In pigs slaughtered in official establishments, the prevalence of Trichinella infection was 0.46% in 1914 and 0.01--0.03% during the period 1990--2004. T. spiralis is typically found in the domestic cycle that includes pigs, humans and rodents. Trichinella spp. from a sylvatic cycle has also caused human outbreaks resulting from the consumption of meat from puma, armadillo and wild boar. European migration to Argentina (principally Spanish and Italian) during the first years of the 20th century brought the tradition of preparing and eating raw sausages. This increased the risk of human exposure to Trichinella. Detection in pigs was initially made at slaughter by compression of muscle tissue (trichinoscopy) and continued this way until 1996, when artificial digestion was adopted for use in preventing human trichinellosis in Argentina. The following report synopsizes the evolution of trichinellosis in Argentina over the past century.
Assuntos
Surtos de Doenças , Parasitologia de Alimentos , Doenças dos Suínos/parasitologia , Trichinella/crescimento & desenvolvimento , Triquinelose/veterinária , Zoonoses/parasitologia , Animais , Argentina/epidemiologia , Humanos , Carne/parasitologia , Estações do Ano , Suínos , Doenças dos Suínos/epidemiologia , Triquinelose/epidemiologia , Triquinelose/parasitologiaRESUMO
Trichinella spiralis infection has been reported sporadically in several areas in Central and South America. However, several countries, including Bolivia, have not reported trichinellosis in animals or humans. A small survey of pigs slaughtered in an abattoir in Bolivia was undertaken during September 1991, to determine the presence of Trichinella spiralis. In a group of 100 pigs slaughtered consecutively on a single day and tested using the pooled digestion method, two of eight pools (25%) were positive. Twenty-one of 188 pigs (11.2%) from ten communities slaughtered consecutively on a second day tested positive for the presence of antibodies to Trichinella spiralis using an enzyme-linked immunosorbent assay. It was concluded that trichinellosis is present in pigs in Bolivia and the rate of infection may be quite high.