Moderate pathogenic effect of Ligophorus uruguayense (Monogenoidea, Ancyrocephalidae) in juvenile mullet Mugil liza (Actinopterygii, Mugilidae) from Brazil.

Monogenoidea pathogenic activity can elicit various histological responses in fish. Species of Ligophorus are specific parasites of mullets, and its relationship with host fish may result in a moderate pathogenic action. In order to ascertain this relationship, estuarine mullets (Mugil liza) were collected in an estuary, reared in laboratory, for three weeks, and forwarded for histological and parasitological analyses.

Gill histopathology of Maria-da-toca Hypleurochilus fissicornis by metacercariae of Bucephalus margaritae (Digenea: Bucephalidae).

Gills of Maria-da-toca Hypleurochilus fissicornis collected at Ponta do Sambaqui-Florianópolis island-Brazil, were analyzed to describe the histopathology caused by metacercaria of Bucephalus margaritae. Gills were submitted to the routine histological techniques for embedding in paraffin and permanent mounting in Balsam and stereoscopic analysis. Metacercariae showed a branchial infection site pattern for encystations.

A comparative study of Ligophorus uruguayense and L. saladensis (Monogenea: Ancyrocephalidae) from Mugil liza (Teleostei: Mugilidae) in southern Brazil.

Representatives of Ligophorus Euzet et Suriano, 1977 were found on the gills of Mugil liza Valenciennes caught in southern Brazil. They were identified as Ligophorus uruguayense Failla Siquier et Ostrowski de Núñez, 2009 and Ligophorus saladensis Marcotegui et Martorelli, 2009, even though specific identification proved to be difficult due to inconsistencies in some diagnostic features reported for these two species. Therefore, a combined morphological and molecular approach was used to critically review the validity of these species, by means of phase contrast and confocal fluorescence microscopical examination of sclerotised hard parts, and assessing the genetic divergence between L.

Histological patterns of the intestinal attachment of Corynosoma australe (Acanthocephala: Polymorphidae) in Arctocephalus australis (Mammalia: Pinnipedia).

The mucosal attachment pattern of Corynosoma australe in the intestines of Arctocephalus australis is described. Normal and abnormal tissue were sampled from 32 hosts to be submitted to histological routine protocol to embedding in paraffin and permanent mounting in balsam. Corynosoma australe shows three different degrees of body depth intestinal attachment (BDINA-1-3).

New technique for collecting eggs from monogenean parasites.

A novel and easily constructed apparatus for collecting monogenean eggs released by the parasites into the water is described and illustrated. Use of this technique may lead to a better understanding of the parasite's biology, which, in turn, may lead to the improvement of parasite management strategies in fish farms where monogeneans are potentially harmful to their hosts. The technique is also useful for studies of eggs or free-living stages of other fish parasites.