The effects of imidacloprid on 1-day-old third instars of Harmonia axyridis were assessed by topical treatment and contact with treated glass plates in laboratory bioassays. When 5 µl of imidacloprid solutions were applied topically, the LD50 was 0.085 g/l per insect after 24 h. Contact with imidacloprid-treated plates had little effect on the number of third instars that became adults. Average duration of larval development was not significantly affected by duration of contact and imidacloprid concentrations. There were no significant differences in maximal larval weight, weight gain and day at maximum larval weight. There were significant differences in average weight gain per day (from third instar to prepupa) after treatments with different imidacloprid concentrations. A temporary knockdown effect was observed with higher concentrations and longer durations of contact with treated plates. Compared with untreated third instars, contact with imidacloprid-treated plates caused an increase in time spent (in seconds) on the glass plates resulting from an increase in number of stops (per second) and angular speed (degrees per second) and a decrease in linear speed, excluding stops (mm/second). The changes in locomotory behavior (i.e., duration of stay on untreated plate, number of stops and angular speed) lasted up to 24 h after contact with imidacloprid-treated plates.
Článek se zabývá masivním vymíráním tří druhů supů ( Gyps bengalensis , Gyps indicus , Gyps tenuirostris ) v jižní Asii. Drastický pokles početnosti supích populací začal v de vadesátých letech minulého století v d ůsledku zavedení nesteroidního protizánětlivého léčiva s n ázvem diclofenac do v eterinární medicíny. V č lánku je popsán mechanismus toxického účinku diclofenacu a t aké jsou zde vysvětleny příči- ny kontaminace supí potravy tímto přípravkem. Speciální pozornost je pak věnována diskusi možných následků vymírání supů jako je zvýšení početnosti populací zdivočelých psů, zvýšené riziko onemocnění lidí vzteklinou a vliv na pohřební rituály členů etnika Pársů., The article deals with massive mortality in three vulture species ( Gyps bengalensis , Gyps indicus , Gyps tenuirostris ) on the South Asian subcontinent, which started in the nineties of the last century. Accidental exposure of scavengers to diclofenac, a non-steroidal anti-inflammatory drug (NSAID), via their food chain is considered to be a scientifically proven reason for the decline of vulture population in India, Pakistan and Nepal. The mechanism of diclofenac toxicity is explained and the sources of diclofenac in vulture food resources are discussed. Special attention is paid to the explanation of possible consequences of vulture extinction as increase in abundance of dog popula- tion, increased number of rabies cases in man, effect on the burial customs of Parsi community., Miloslav Pouzar, and Literatura