title: Immunological Profile of the Yellow Clam Mesodesma mactroides (Mesodesmatidae) from the Southern Coast of Rio Grande do Sul, Brazil.
abstract: The yellow clam Mesodesma mactroides (Mesodesmatidae) is a sandy beach bivalve that is distributed from Rio de Janeiro, Brazil, to the south of Buenos Aires province, Argentina. The yellow clam population has been declining in recent decades. To increase our understanding of this species, we evaluated the immunological status of yellow clams collected during different seasons from various areas in the state of Rio Grande do Sul, Brazil. We characterized the hemocytes, determined the differential hemocyte counts (DHCs), calculated the apoptotic index, and evaluated the incidence of parasites in yellow clams through histological analysis. We identified two types of hemocyte (hyaline and granular) that showed significant variation in DHCs among sampling areas during the summer and winter. The apoptotic index only exhibited significant variation during the summer. Histopathological analysis results did not significantly differ among sampling areas. This work demonstrated that environmental variation (e.g., temperature and salinity) associated with anthropogenic actions may be affecting the immune system of yellow clams. However, more studies are needed to determine the full influence of these factors on the yellow clam's immune system and thus contribute to future management and aquaculture of the species. Received May 10, 2015; accepted October 28, 2015.
authors.affiliation: a Laboratório de Patologia de Organismos Aquáticos , Universidade Federal do Rio Grande , Codigo Postal 474, Rio Grande, Rio Grande do Sul 96201-900 , Brazil.
authors.forename: Juan Jethro
authors.initials: JJ
authors.lastname: Silva Santos
authors.affiliation: a Laboratório de Patologia de Organismos Aquáticos , Universidade Federal do Rio Grande , Codigo Postal 474, Rio Grande, Rio Grande do Sul 96201-900 , Brazil.
authors.forename: Yuri Bovi
authors.initials: YB
authors.lastname: Carvalho
authors.affiliation: b Laboratório de Piscicultura Estuarina e Marinha , Universidade Federal do Rio Grande , Codigo Postal 474, Rio Grande, Rio Grande do Sul 96201-900 , Brazil.
authors.forename: Diogo Luiz
authors.initials: DL
authors.lastname: de Alcantara Lopes
authors.affiliation: a Laboratório de Patologia de Organismos Aquáticos , Universidade Federal do Rio Grande , Codigo Postal 474, Rio Grande, Rio Grande do Sul 96201-900 , Brazil.
authors.forename: Luis Alberto
authors.initials: LA
authors.lastname: Romano
mesh_terms: D063147:Animal Distribution; D000818:Animals; D049872:Bivalvia / Q000276:immunology* / Q000502:physiology; D001938:Brazil; D006434:Hemocytes / Q000166:cytology