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Freshwater crayfish Cherax quadricarinatus have a high commercial value and are cultured in farms where they are potentially exposed to pesticides. Therefore, we examined the sublethal effects of a 50-day exposure to glyphosate acid and polyoxyethylenamine (POEA), both alone and in a 3:1 mixture, on the growth and energetic reserves in muscle, hepatopancreas and hemolymph of growing juvenile crayfish. Exposure to two different glyphosate and POEA mixtures caused lower somatic growth and decreased muscle protein levels. These effects, caused by both compounds interacting in the mixture, could also be synergistic because they were expressed even at the lowest concentration. The decrease in protein levels could be related to the greater use of other energy reserves. This hypothesis is supported by the decrease in muscle glycogen stores due to glyphosate exposure and the decrease in lipid reserves associated with exposure to POEA.

 Abstract Viau, V. E., López Greco, L. S., Bond-Buckup, G. & Rodriguez, E. M. 2006. Size at the onset of sexual maturity in the anomuran crab, Aegla uruguayana (Aeglidae). -Acta Zoologica (Stockholm) 87 : 253-264The size at maturity was studied in the crab Aegla uruguayana from the Areco River (31 ° 14 ′ S, 59 ° 28 ′ W), Argentina. Size at sexual maturity was determined according to three criteria: morphometric (change in the relative growth of reproductive characters), histological (first maturation of gonads) and functional (capability to mate and carry eggs). Regarding females, morphometric maturity occurred at a carapace length (CL) of 11.50 mm, considering abdomen width as a reproductive character. Gonad maturity of females could be observed at a minimum size ranging from 15 to 17 mm CL. The smallest ovigerous female observed in the field was 15.60 mm CL, although a relevant population incidence of ovigerous females (86.6%) has just been observed at values higher than 17 mm CL. As for males, the relative growth of the left chela length changed at a value of 15.40 mm CL, while morphological changes in sexual tube occurred between CL of 14 and 16 mm. Testicular maturation occurred at a CL ranging from 17 to 19 mm. The smallest size of males having spermatozoids in their vasa deferentia was 18.70 mm CL. The results obtained indicated that, in both sexes, functional maturity occurred after morphometric maturity and at a size similar to that of gonad maturity. Comparing sexes, females acquired sexual maturity (morphometric, gonad and functional maturity) at sizes statistically smaller than those of males.

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Abstract. Morphological abnormalities were noted in larvae hatched from ovigerous females of the estuarine crab Chasmagnathus granulata, exposed to 1 and 15 rag/1 of cadmium during the egg incubation period. The highest concentration produced a significant incidence of hydropsy, atrophy of dorsal spine, pleon and pereiopods as well as enhancement of pigmentation. Some possible causes of these results are discussed and compared with the effects caused by other pollutants on the same species.