Effects of Bucephalus sp. (Trematoda: Bucephalidae) on Perna perna mussels from a culture station in Ratones Grande Island, Brazil.
This study reports the prevalence of Bucephalus sp. in Perna perna populations from a culture station of southern Brazil and its effect on the mussel reproductive tissue and immune system. The prevalence of Bucephalus sp. in P. perna (n = 1871) was considered low (3.1%) and did not seasonally vary. Histological sections of the mantle of infected mussels revealed a marked (80%) reduction of the reproductive tissue that was severe even in mussels exhibiting a moderate infection degree. The total (THC) and differential (DHC) hemocyte counts were lower in infected mussels (3.9 x 10(6) hem/ml; granular hemocytes = 33%) as compared with non-infected animals (5.5 x 10(6) hem/ml; granular hemocytes = 40%). The plasma protein concentration did not vary upon infection. Hemocyte infiltration was significantly higher only in mussels with a very heavy infection degree. The parasite sporocysts were never seen encapsulated by the host hemocytes. Our results indicate that Bucephalus sp. promotes a severe castration in its host and apparently evades the mussel immune system.
Departmento de Biologia Celular, Embriologio e Genética, Universidade Federal de Santa Catarina, C.P. 476, Florianópolis 88.040-900, Brazil.
Patrícia M
PM
da Silva
Aimê R M
AR
Magalhães
Margherita A
MA
Barracco
D000818:Animals; D049872:Bivalvia / Q000469:parasitology*; D001938:Brazil; D006434:Hemocytes; D014200:Trematoda / Q000502:physiology*; D014201:Trematode Infections / Q000469:parasitology / Q000473:pathology / Q000662:veterinary