Human dispersal of Trichinella spiralis in domesticated pigs

To investigate the human impact on the evolutionary ecology of animal pathogens, we compared genetic diversity of severe foodborne parasites contracted by eating infected pork or wild game. In particular, we characterized Trichinella spp. from twenty-eight countries and four continents by genotyping nine microsatellite loci and sequencing one-fifth of the mitochondrial genome. All specimens of Trichinella spiralis, a swine parasite that can infect many species of wildlife, were remarkably uniform across Europe, North Africa, and the Americas. Far greater diversity characterized a comparable sample of Trichinella britovi, which parasitizes various sylvatic mammals endemic to Eurasia and North-Western Africa. A limited sample of T. spiralis in Asia, where swine were first domesticated, encompassed greater genetic variability than those in the West, as did small samples of Trichinella nativa and Trichinella murrelli, which parasitize wildlife hosts. We conclude that European lineages of T. spiralis originated several thousand years ago, approximately when pigs were first domesticated there. These data also imply that Europeans inadvertently introduced T. spiralis to the Americas via infected pigs and/or rats. Despite evidence that early hominid hunters ingested foodborne parasites by hunting wild game millions of years earlier, swine husbandry has governed the subsequent transmission, dissemination, and evolutionary diversification of T. spiralis. Where viable parasites have been eliminated from their diet, the residual risk posed to swine by exposure to wildlife or rats should be more precisely defined because breaking the cycle of transmission would confer enduring economic and health benefits

\u3ci\u3eParelaphostrongylus odocoilei\u3c/i\u3e in Columbia Black-Tailed Deer from Oregon

Documenting the occurrence of Parelaphostrongylus odocoilei has historically relied on the morphological examination of adult worms collected from the skeletal muscle of definitive hosts, including deer. Recent advances in the knowledge of protostrongylid genetic sequences now permit larvae to be identified. Dorsal-spined larvae (DSLs) collected in 2003–2004 from the lung and feces of six Columbian black-tailed deer (Odocoileus hemionus columbianus) from Oregon were characterized genetically. The sequences from unknown DSLs were compared to those from morphologically validated adults and larvae of P. odocoilei at both the second internal transcribed spacer (ITS-2) of ribosomal DNA and the mitochondrial cytochrome oxidase II gene. We provide the first unequivocal identification of P. odocoilei in Columbian black-tailed deer from Oregon. The broader geographic distribution, prevalence, and pathology of P. odocoilei are not known in populations of Oregon deer

Human dispersal of Trichinella spiralis in domesticated pigs

To investigate the human impact on the evolutionary ecology of animal pathogens, we compared genetic diversity of severe foodborne parasites contracted by eating infected pork or wild game. In particular, we characterized Trichinella spp. from twenty-eight countries and four continents by genotyping nine microsatellite loci and sequencing one-fifth of the mitochondrial genome. All specimens of Trichinella spiralis, a swine parasite that can infect many species of wildlife, were remarkably uniform across Europe, North Africa, and the Americas. Far greater diversity characterized a comparable sample of Trichinella britovi, which parasitizes various sylvatic mammals endemic to Eurasia and North-Western Africa. A limited sample of T. spiralis in Asia, where swine were first domesticated, encompassed greater genetic variability than those in the West, as did small samples of Trichinella nativa and Trichinella murrelli, which parasitize wildlife hosts. We conclude that European lineages of T. spiralis originated several thousand years ago, approximately when pigs were first domesticated there. These data also imply that Europeans inadvertently introduced T. spiralis to the Americas via infected pigs and/or rats. Despite evidence that early hominid hunters ingested foodborne parasites by hunting wild game millions of years earlier, swine husbandry has governed the subsequent transmission, dissemination, and evolutionary diversification of T. spiralis. Where viable parasites have been eliminated from their diet, the residual risk posed to swine by exposure to wildlife or rats should be more precisely defined because breaking the cycle of transmission would confer enduring economic and health benefits

The controversy of interpretations and the reproductive movement of Brazilian agriculture in the 1980s.

Analisa-se o movimento concreto experimentado pela agropecuária brasileira na década de 1980, tomando por base o ciclo de valorização do capital e as leis que o regem a partir da teoria marxista. Antes, porém, apresenta-se o processo recente de transformações ocorridas no setor e as diversas frentes interpretativas as quais são caracterizadas como viéses. A análise conclui que no período a agropecuária é marcada por um processo cíclico, marcado por crises tanto conjuntural quanto estrutural. Entretanto, a evidenciação ou não da crise depende do parâmetro tomado como objeto de análise e que pela desagregação têm-se produtos e grupos de produtos que parecem não ter tomado conhecimento da crise, ao passo que outros foram afetados significativamente.The concrete movement experienced by agriculture is analyzed. in the 1980s, based on the of capital and the laws that govern it from Marxist theory. Before, However, the recent process of sector and the various interpretative fronts which are characterized by as biases. The analysis concludes that in the period the agriculture and livestock is marked by a cyclical process, marked by cyclical structural. However, whether or not the evidence of the crisis is parameter taken as the object of analysis and that by the disaggregation products and product groups that appear to have been unaware of of the crisis, while others were significantly affected