Reproductive biology of the Neotropical catfish Iheringichthys labrosus (Siluriformes: Pimelodidae), with anatomical and morphometric analysis of gonadal tissues

The purpose of this study was to analyze the population structure (spatial and temporal distribution, sex ratio, length distribution and length/weight relationship) and reproductive biology of Iheringichthys labrosus. This species is of importance as fisheries resource in the Paraná River basin. Fish were sampled, bimonthly, with gill and trammel nets at three sampling sites (Campina, Apertado and Altônia), located in the Piquiri River, between November 2002 and September 2003. In this study, 164 individuals were collected; the largest capture occurred in Campina site, with 209.88 individuals/1000 m² of net for 24 hours, while the shift of largest capture was night time (N) and the month was July. Females occurred in larger numbers than males in all periods. The growth was allometric positive and the reproduction period was from the beginning of September to the end of December, with the majority of the individuals showing a standard length between 13.0 and 20.0 cm.

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Morphometric Analysis of the Hepatocytes from Fish Exposed to Arsenic

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100091391 ◽

1976 ◽

Vol 34 ◽

pp. 282-283

Author(s):

Elsie M. B. Sorensen

Keyword(s):

Morphometric Analysis ◽

Arsenic Concentration ◽

Ultrastructural Changes ◽

Sodium Arsenate ◽

Lepomis Cyanellus ◽

Mammalian Counterpart ◽

Intracellular Changes ◽

Green Sunfish ◽

Organic Pesticides

The detoxification capacity of the liver is well documented for a variety of substances including ethanol, organic pesticides, drugs, and metals. The piscean liver, although less enzymatically active than the mammalian counterpart (1), contains endoplasmic reticulum with an impressive repertoire of oxidizing, reducing, and conjugating abilities (2). Histopathologic changes are kncwn to occur in fish hepatocytes following in vivo exposure to arsenic (3); however, ultrastructural changes have not been reported. This study involved the morphometric analysis of intracellular changes in fish parynchymal hepatocytes and correlation with arsenic concentration in the liver.Green sunfish (Lepomis cyanellus, R.) were exposed to 0, 30, or 60 ppm arsenic (as sodium arsenate) at 20°C for 1, 2, or 3 week intervals before removal of livers for quantification of the arsenic burden (using neutron activation analysis) and morphometric analysis of ultrastructural alterations. Livers were cut into 1 mm cubes for fixation, dehydration, and embedding.

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Fine structure and possible functions of the hermaphrodite duct of some pulmonate snails (Mollusca: Gastropoda)

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100157887 ◽

1990 ◽

Vol 48 (3) ◽

pp. 68-69

Author(s):

Alan N. Hodgson

Keyword(s):

Electron Microscopy ◽

Transmission Electron Microscopy ◽

Fine Structure ◽

Seminal Vesicle ◽

Reproductive Biology ◽

Light Microscope ◽

Light Microscope Level ◽

Transmission Electron ◽

Standard Techniques

The hermaphrodite duct of pulmonate snails connects the ovotestis to the fertilization pouch. The duct is typically divided into three zones; aproximal duct which leaves the ovotestis, the middle duct (seminal vesicle) and the distal ovotestis duct. The seminal vesicle forms the major portion of the duct and is thought to store sperm prior to copulation. In addition the duct may also play a role in sperm maturation and degredation. Although the structure of the seminal vesicle has been described for a number of snails at the light microscope level there appear to be only two descriptions of the ultrastructure of this tissue. Clearly if the role of the hermaphrodite duct in the reproductive biology of pulmonatesis to be understood, knowledge of its fine structure is required.Hermaphrodite ducts, both containing and lacking sperm, of species of the terrestrial pulmonate genera Sphincterochila, Levantina, and Helix and the marine pulmonate genus Siphonaria were prepared for transmission electron microscopy by standard techniques.

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