Histological Arguments concerning Hepatic Larval Migration in Natural Infestation with Ascaris Suum in Pigs

Fragments of the liver were collected and processed histologically, from six swine four months age, having positive coproculture tests for Ascaris suum. On microscopic examinations were observed larval migration routes. A small number of them did not present reparatory processes, which showed that they were relatively recent. Most of the areas affected presented reparatory processes in different stages of consolidation. The lobules from affected areas presented structural changes by different intensity, with the appearance of pseudolobules or even total disorganisation with the persistence of small groups of hepatocytes dispersed in connective tissue proliferated in the area. In some portions, connective tissue occupied more than half of the section surface and has an obvious tendency of fibrous consolidation. Expanding of fibrous areas by repeated infestation could be represent one of the factors that start liver cirrhosis.