scholarly journals Comparative Study of Various Immune Parameters in Three Bivalve Species during a Natural Bloom of Dinophysis acuminata in Santa Catarina Island, Brazil

Toxins ◽  
2010 ◽  
Vol 2 (5) ◽  
pp. 1166-1178 ◽  
Author(s):  
Danielle Ferraz Mello ◽  
Luis Antonio de Oliveira Proença ◽  
Margherita Anna Barracco
Author(s):  
Erik Simões ◽  
Renato Campos Vieira ◽  
Mathias Alberto Schramm ◽  
Danielle Ferraz Mello ◽  
Vitor De Almeida Pontinha ◽  
...  

Blooms of the harmful alga Dinophysis acuminata, which produces okadaic acid (OA), are becoming recurrent in Santa Catarina coast, where most of the shellfish marine farms in Brazil are located. We evaluated the impact of D. acuminata blooms on various haemato-immunological parameters and on tissue integrity of cultivated oysters (Crassostrea gigas) and mussels (Perna perna). Animals were sampled during two natural algal blooms, one at Praia Alegre (PA: 2950 cells l−1) and the other at Praia de Zimbros (PZ: 4150 cells l−1). Control animals were sampled at the same sites, 30 days after the end of the bloom. The assayed parameters were: total (THC) and differential (DHC) haemocyte counts, percentage of apoptotic haemocytes (AH), phenoloxidase activity (PO), agglutinating titre (AT) and total protein concentration in haemolymph (PC). Histological analyses were carried out in oysters from PZ. The results showed that some immune parameters were modulated during the toxic blooms, but not in a consistent manner, especially in mussels that accumulated more OA (10×) than oysters. For example, mussel THC decreased significantly (54%) during the bloom at PA, whereas it augmented markedly (64%) at PZ. PO activity was significantly altered by the algal blooms in both bivalve species, while PC increased significantly (66%) only in mussels from PZ bloom. The other parameters (DHC, AH and AT) did not vary in both bivalve species. Histological analyses showed an intense haemocytic infiltration throughout the oyster digestive epithelium, particularly into the stomach lumen during the algal bloom.


Author(s):  
Patricia Mirella da Silva ◽  
Aimê Rachel Magenta Magalhães ◽  
Margherita Anna Barracco

The State of Santa Catarina in southern Brazil is the most important Brazilian producer region. The Pacific oysters Crassostrea gigas and the brown mussels Perna perna are the main species currently produced. The occurrence and impact of parasites on bivalves from natural or culture populations from Brazil are still poorly studied. This work describes several diseases, parasites and commensals from four edible bivalve species, from cultured and exploited stocks, from five sites at Santa Catarina State. Unspecific histopathological symptoms of stress, parasites and commensals were found, including viral gametocytic hypertrophy and rickettsia-like organisms with very low prevalences; the protozoan Nematopsis sp. with high prevalence and, ovarian parasites with low prevalences; and, diverse metazoans, such as turbellarian, sporocysts and metacercariae of trematodes, metacestoda larvae and spionid polychaete. Ray's fluid thioglycollate medium assays for detection of Perkinsus spp. did not detect any infected bivalves. Polymerase chain reaction assays for Marteiliodies chungmuensis in oysters with ovarian lesions produced negative results.


2020 ◽  
Vol 66 (10) ◽  
pp. 1338-1343
Author(s):  
Tânia Rita Moreno de Oliveira Fernandes ◽  
Anderson de Almeida Pereira ◽  
Lara Sodré Cardoso ◽  
Valdir Pereira Alves Filho ◽  
Luiz Sergio Nunes de Rezende Junior ◽  
...  

SUMMARY OBJECTIVE: We compared the hidden prevalence of leprosy in two Brazilian cities with distinct differences regarding geographic region and socio-economic development profile, namely, Juazeiro, Bahia and Joinville, Santa Catarina. METHODS: A retrospective epidemiological study based on secondary data obtained from leprosy case notifications in the cities of Juazeiro-BA and Joinville-SC, 2007-2017. To calculate hidden prevalence, we used the method proposed by Gil Suárez and Lombardi. RESULTS: Joinville had 105 cases of leprosy that went undiagnosed (addition of 42.0% to the registered prevalence). For Juazeiro, it was estimated that 295 cases went undiagnosed (addition of 18.9%). CONCLUSION: Joinville presents a higher hidden prevalence than Juazeiro.


2020 ◽  
Author(s):  
Bruno Oliveira Ferreira de Souza ◽  
Éve‐Marie Frigon ◽  
Robert Tremblay‐Laliberté ◽  
Christian Casanova ◽  
Denis Boire

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