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Age and growth of Sardinella aurita larvae were analyzed based on daily growth increments in sagitta otoliths. Larvae were obtained from ichthyoplankton samples collected from the outer shelf off Margarita Island and from Mochima Bay (northeastern Venezuela), between March 1999 and January 2001. Total length, standard length (SL) and height of larvae were measured and the otoliths were examined under a light microscope. Larval size ranged from 1.35 to 15.90 mm SL, the Margarita Island larvae being signicantly larger than those from Mochima (t = 18.69; P < 0.001). The three morphological parameters were significantly and positively correlated among themselves and with otolith diameter and age, and fitted to a linear regression model; hence, size growth as a function of age was not different between the localities studied (SL = 2.65 + 1.10 × age; r² = 0.78, P < 0.001). Growth rates per locality were also determined by backcalculating sizes, with no significant differences (F = 2.60, P > 0.05) between them. The mean backcalculated growth rate was 0.99 mm day-1 and it was not significantly different from the mean growth rate obtained from fitted length-age data (F = 3.32, P > 0.05). Morphological changes in otoliths were evident from the mean daily increment widths, with wider increments in larval otoliths from Margarita Island (H = 42.54, P < 0.001). [ABSTRACT FROM AUTHOR]

Abstract: The Arrau turtle (Podocnemis expansa) is an endangered species, as a result of long-lasting, unsustainable exploitation. To obtain reference haematological values from the wild Podocnemis expansa during post-laying, 20 turtles were captured in the Orinoco River. Blood was obtained from the dorsal cervical sinus in lithium heparin tubes. Red blood cells (RBC), white blood cells (WBC), thrombocytes (TC), packed cell volume (PCV), plasmatic protein (PP), haemoglobin (Hgb), mean corpuscular volume (MCV) and differential leukocyte count were determined. Haematological values were: RBC 0.9×109/L, WBC 5.7×109/L, TC 5.4×109/L, PCV 35.6%, PP 4.2g/dL, Hgb 11.8g/dL, MCV 411fL. The differential leukocyte count comprised: 71% heterophils, 23% lymphocytes, 3% eosinophils, 1.6% basophils, and 1% monocytes. The reports of reference haematology values for the wild P. expansa are limited; therefore, the results presented herein contrast with those values obtained in captivity. This study represents a contribution to the referential haematological values of the wild P. expansa. [Copyright &y& Elsevier]