Eurytrema coelomaticum (Giard & Billet) (Digenea, Dicrocoeliidae) em Bradybaena similaris (Férussac) (Gastropoda, Xanthonychidae): alterações nos depósitos de cálcio e na função reprodutiva do primeiro hospedeiro intermediário

Eurytrema coelomaticum (Giard & Billet) (Digenea, Dicrocoeliidae) em Bradybaena similaris (Férussac) (Gastropoda, Xanthonychidae): alterations in calcium deposits and in the reproductive function of its first intermediate host

Eurytrema coelomaticum; Bradybaena similaris; calcium deposits; parasitic castration

Eurytrema coelomaticum (Giard & Billet) (Digenea, Dicrocoeliidae) em Bradybaena similaris (Férussac) (Gastropoda, Xanthonychidae): alterações nos depósitos de cálcio e na função reprodutiva do primeiro hospedeiro intermediário

Eurytrema coelomaticum (Giard & Billet) (Digenea, Dicrocoeliidae) em Bradybaena similaris (Férussac) (Gastropoda, Xanthonychidae): alterations in calcium deposits and in the reproductive function of its first intermediate host

Solange V. Paschoal^I; Suzana B. Amato^I,II

^IDepartamento de Biologia Animal, Universidade Federal Rural do Rio de Janeiro. Caixa postal 74555, 23851-970 Itaguaí, Rio de Janeiro, Brasil

^IIPesquisadora do CNPq

ABSTRACT

The influence of the parasitism by the digenetic trematode Eurytrema coelomaticum (Giard & Billet, 1892) over the calcium mobilization and the reproductive function of its first intermediate host, the snail Bradybaena similaris (Férussac, 1821) was experimentally studied in infected and uninfected snails maintained in laboratory under controlled conditions of nutrition, humidity and temperature. The calcium of the shells of infected and uninfected snails was quantified by using a technique of volumetric complexation. The amount of calcium present in the tissue was evaluated by using the histochemistry techniques of Dahl and von Kossa. The alteration in the reproductive function was evaluated through the egg production, and by histological follow up of the snails gametogenesis, in the infected and uninfected snails. The Student's test "t" showed that there was no significant difference in relation to size, weight and calcium concentration in the shells of infected and uninfected snails. The analysis of nonlinear regression, polynomial of 4^th order, showed an highly positive relation to weight and size of shell to infected and uninfected snails, and an weakly significant relation to calcium concentration in the shells and shells size of infected snails. The histochemistry techniques demonstrated a large calcium deposition in the cells of the digestive glands of the infected snails when compared to the uninfected ones. The histological study of the ovotestis of the infected snails demonstrated that the gametogenesis of these snails was abnormal. The ovulogenesis was the most alterated and at 45 days post-infection the histological sections showed no ovocytes present in the ovotestis.

Key words:Eurytrema coelomaticum, Bradybaena similaris, calcium deposits, parasitic castration

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Recebido em 28.XII.1995; aceito em 11.X.1996.

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Datas de Publicação

• Publicação nesta coleção
  14 Jul 2009
• Data do Fascículo
  1996

Histórico

• Recebido
  28 Dez 1995
• Aceito
  11 Out 1996