Acute toxic effects of malathion on the 21st stage larvae of the marsh frog

Currently, amphibian decline is accepted as a global problem. One of the most important proposed causes for the decline is the use of agrochemicals, especially pesticides. Nevertheless, information about the impact of pesticides on amphibian populations remains scarce. The present study sought to identify the effects of malathion, an organophosphorus insecticide, on 21st stage larvae of the marsh frog, Rana ridibunda, with an acute toxicity test using a static system. Each experimental group contained 10 healthy larvae and was exposed to different concentrations of technical and formulation grade malathion for 96 h. Concentrations of malathion that caused 50% mortality (LC50) at 96 h were estimated using a probit analysis program. The results showed that formulation grade malathion (LC50 = 29 ppm) was more toxic than technical grade malathion (LC50 = 38 ppm). Malformations, certain signs of toxicity (hyperactive symptoms, loss of balance, motionlessness, and death), and growth retardation were observed in malathion-treated larvae. © TÜBİTAK

ophryticus)

Paedomorphs and metamorphs of the northern banded newt (Ommatotriton ophryticus) were compared with respect to body size and some reproductive traits. Paedomorphic females are smaller than metamorphic individuals of the same sex. Both morphs have a similar reproduction pathway in terms of egg number and incubation period, while hatching success and egg diameter appear to be different between morphs. Survival rates of two morphs were significantly different and calculated as 66% for paedomorphs, and 81% for metamorphs. On the other hand, both forms shared a common allometric slope of the SVL vs. number of eggs and egg diameter, and larger females tend to produce more and larger eggs

ophryticus)

Paedomorphs and metamorphs of the northern banded newt (Ommatotriton ophryticus) were compared with respect to body size and some reproductive traits. Paedomorphic females are smaller than metamorphic individuals of the same sex. Both morphs have a similar reproduction pathway in terms of egg number and incubation period, while hatching success and egg diameter appear to be different between morphs. Survival rates of two morphs were significantly different and calculated as 66% for paedomorphs, and 81% for metamorphs. On the other hand, both forms shared a common allometric slope of the SVL vs. number of eggs and egg diameter, and larger females tend to produce more and larger eggs

salamander, Mertensiella caucasica in the Western Lesser Caucasus

Selection of breeding habitat plays a fundamental role in the reproductive success of urodeles and anurans. We studied the influence of water chemistry variables on the selection of a specific water resource as breeding habitat in Mertensiella caucasica. To determine the influence of water chemistry parameters on their habitat selection, we surveyed a total of 45 small river, streams and brooks in the Western Lesser Caucasus (northeastern Turkey and southwestern Georgia). The water samples taken from these localities were analyzed for 14 chemical variables and the results submitted to multiple logistic regression analysis in order to evaluate the influence of these parameters on the presence or absence of the species in the localities. Of these parameters, chloride concentration influenced the breeding habitat selection of Mertensiella caucasica significantly. To cite this article: F. Sayim et al., C. R. Biologies 332 (2009). (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved

In vivo effects of Malathion on Glutathione-S-transferase and acetylcholinesterase activities in various tissues of neonatal rats [Yenidogan Siçanlarin Çeşitli Dokularindaki Glutation-S-Transferaz ve Asetilkolinesteraz Aktiviteleri üzerine Malation'un In vivo Etkileri]

Glutathione-S-transferase (GST) has been reported to play an important role in the detoxification of several chemical compounds including pesticides. Organophosphate pesticides are potent inhibitors of acetylcholinesterase (AChE). The present study was conducted to assess the in vivo effects of the organophosphate pesticide malathion on the activity of GST and AChE and the protein levels of different organs in neonatal rats. GST activity increased approximately two-fold in adult female rats fed malathion. whereas AChE activity decreased less than 20% of the control in the liver. Similarly, liver and heart GST activities (0.14 and 0.035 U/mg protein, respectively) were also increased approximately two-fold in neonatal rats, but in the brain a decrease in GST activity (0.074 U/mg protein) was observed. The acetylcholinesterase activity in the liver, brain, kidney and lung (0.002, 0.035, 0.046, and 0.018 U/mg protein, respectively) seemed to be significantly decreased compared with the control. There was no significant change in protein contents. In conclusion, it is suggested that malathion has some biochemical effects on rats

Izmir, Turkey (Amphibia: Anura)

We studied the breeding biology of the Green Toad, Pseudepidalea viridis (Laurenti, 1768), in the 2007-2008 breeding seasons at Kocacay Stream. The breeding period began in early February and lasted approximately two months. The median of the breeding seasons was calculated as 5'March for the entire study period 2007-2008. The average clutch size was 14,594 eggs and this value was higher than in other conspecific populations from Denmark, Israel and Italy. Clutch size and clutch mass were significantly correlated with female body size, but single egg mass and egg diameter were not. A negative significant correlation was seen between clutch size and egg diameter

Paedomorphosis in the banded newt, Triturus vittatus (Jenyns, 1835)

[No abstract available

Izmir, Turkey (Amphibia: Anura)

We studied the breeding biology of the Green Toad, Pseudepidalea viridis (Laurenti, 1768), in the 2007-2008 breeding seasons at Kocacay Stream. The breeding period began in early February and lasted approximately two months. The median of the breeding seasons was calculated as 5'March for the entire study period 2007-2008. The average clutch size was 14,594 eggs and this value was higher than in other conspecific populations from Denmark, Israel and Italy. Clutch size and clutch mass were significantly correlated with female body size, but single egg mass and egg diameter were not. A negative significant correlation was seen between clutch size and egg diameter