Navegando por Assunto "Brachyplatystoma rousseauxii"

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Acesso aberto (Open Access)
Fauna microparasitária de Brachyplatystoma rousseauxii e Mugil curema desembarcados na Amazônia oriental
(Universidade Federal do Pará, 2013-11-29) DIAS, Lilian de Nazaré Santos; MATOS, Edilson Rodrigues; http://lattes.cnpq.br/7895814591867510; PAIVA, Rosildo Santos; http://lattes.cnpq.br/0510818763187669; FREITAS, José de Arimatéa; http://lattes.cnpq.br/2382745365421156
The gilthead bream Brachyplatystoma rousseauxii and white mullet Mugil curema are species of fish consumption and considerable commercial value found in estuarine cost of Pará The microparasites phyla Apicomplexa, Microspora and Myxozoa are organisms that can be found parasitizing vertebrates and invertebrates, including the fish, some pathogenic potential and even zoonotic and economic impact. To discover the fauna microparasites affecting fish , 62 specimens of B. rousseauxii and 58 M. curema estuarna captured on the coast of the city of Vigia de Nazare and Mosqueiro District, in Belem, Para state were examined as methods and techniques for morphological analysis (microscopy light), ultrastructural (transmission electron microscopy, TEM) and molecular biology (phylogenetic analysis). It was observed that there are three phyla (three in B. rousseauxii and two in M. curema) captured hosts in the two locations , plus the largest parasitic index was determined in specimens of both captured on the coast of the estuarine Vigia de Nazare , higher incidence of co microparasites phyla Apicomplexa and Myxozoa, beyond multiparasitism in B. rousseauxii Morphological analysis revealed the presence of Calyptospora sp. (Apicomplexa), Ellipsomyxa sp., Henneguya sp., Myxobolus sp. and Meglishcha sp. (Myxozoa) and Kabatana sp. (Microspora) in B. rousseauxii and Ellipsomyxa sp., Myxobolus sp. and Microspora phylum microparasito in M. curema. The data analysis of morphological and ultrastructural Myxospora found in B. rousseauxii and M. curema are suggestive of new species microparasites these two hosts. Phylogenetic analysis of the data did not provide results that allow the classification of Kabatana sp. (Microspora) and Henneguya sp. (Myxozoa) found parasitizing B. rousseauxii microparasites as new species in this host due to low bootstrap value, but by analyzing the distance p was possible to suggest that these are new species. Studies about microparasites in Amazonian fish are needed for the knowledge of the occurrences, characterization d new species, the pathogenic potential hosts and possible risk to the consumer.
Acesso aberto (Open Access)
Morfometria e descrição de otólitos de dourada (Brachyplatystoma rosseauxii) (Castelnau, 1855) e de piramutaba (B. vaillantii) (Valenciennes, 1840) (Siluriformes: pimelodidae) e verificação de anéis de crescimento em otólitos de juvenis de dourada e de piramutaba na Ilha de Colares - Baía de Marajó-PA
(Universidade Federal do Pará, 2008-10-09) PIRKER, Lilianne Esther Mergulhão; BARTHEM, Ronaldo Borges; http://lattes.cnpq.br/4192105831997326
The dourada (Brachyplatystoma rousseauxii) and the piramutaba (B. vaillantii), two migratory freshwater catfishes, are exploited by both traditional and industrial fishery in the Amazonian. They are very important for the commercial fishery in this region and their stocks are currently sobrexploted. However there is a lack of information concerning the biology and ecology of juvenile stages of these catfishes in the scientific literature. In population dynamics studies, the correct age estimate influences the growth parameters, which are important to evaluate stocks. The studies of age determination are usually made using sub-adults and adults specimens. The juveniles are not analyzed and their age is back-calculated. Which could result in an error estimate. The aims of the present research were: (1) to describe and estimate the relation between the lapilli otoliths morfometric measurements and the body measurements of dourada and piramutaba, and (2) to examine the occurrence of the first growth rings in the juvenile specimens. The morfometric and descriptive studies were carried out using otoliths from dourada and piramutaba juveniles, sub-adults and adults collected in the municipalities of Colares (PA), Almeirim (PA), Santarém (PA), and Manaus (AM), in the District of Mosqueiro (PA), and in the Amazon estuary. The period of collection was different for each local, to September of 1996 to January of 2006. The following relations were estimated: furcal length from specimens (LF) x total weight from specimens (WT); LF x maximum otolith length (MOL); LF x maximum otolith width (MOW); LF x otolith total weight (OWT); WT x MOL; WT x MOW and WT x OWT. The estimated equations were: Dourada: WT = 9.5 x 10-6 x LF 3.0279, LF = 25.259 * MOL1.1571, LF = 40.626 * MOW1.2127, LF = 840.419 * OWT0.4077, WT = 0.125 * MOL3.6547, WT = 0.568 * MOW3.8294, WT = 7549.98 * OWT1.2651; Piramutaba: WT = xxx 5.4 x 10-6 x LF 3.1441, LF = 31.871 * MOL1.3381, LF = 55.852 * MOW1.3722, LF = 1641.064 * OWT0.4686, WT = 0.3127 * MOL4.1857, WT = 1.823 * MOW4.2788, WT = 66675.977 * OWT1.4508. In the descriptive study, the lapilli of dourada and piramutaba were classified in the following categories according to their development and specimens LF: dourada I (60 a 80 mm), dourada II (80 a 110 mm), dourada III (110 a 210 mm), piramutaba I (65 a 80 mm), piramutaba II (80 a 110 mm), and piramutaba III (110 a 190 mm). In the lapillus ring reading study, only the juveniles specimens £ 200 mm LF were used. In the Marajó bay, douradas and piramutabas with 175.03 mm and 171.03 mm mean LF, respectively, showed the first growth ring. Both species were between nine and twelve months old when they showed the first growth ring. The mean rays of the first hyaline ring in the transversal cut of dourada’s and piramutaba’s lapillus were 0.36 mm (± 0.03) and 0.33 mm (± 0.01), respectively. The mean total ray of the lapillus transversal cut was 0.64 mm (± 0.14) in dourada and 0.53 mm (± 0.09) in piramutaba. The estimated equation relating the total ray of the lapillus transversal cut of douradas juveniles with its LF was LF = 248.589 * Rt1.1901. The estimated equation for piramutaba was LF = 400.494 * Rt1.7178. Douradas and piramutabas 60-70 mm LF were three to six months old, 70-110 mm LF were six to nine months old, and 110-200 mm LF were nine to twelve months old.