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Environmental fate of chlorantraniliprole and indoxacarb termiticides and bioefficacy against eastern subterranean termites, Reticulitermes flavipes (Kollar) (Isoptera: Rhinotermitidae)Spomer, Neil A. January 2009 (has links)
Thesis (Ph.D.)--University of Nebraska-Lincoln, 2009. / Title from title screen (site viewed October 15, 2009). PDF text: xii, 210 p. : ill. ; 1.21 Mb. UMI publication number: AAT 3359065. Includes bibliographical references. Also available in microfilm and microfiche formats.
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The effects of copper on the degradation of atrazine and indoxacarb in a New Zealand soil : a thesis submitted in partial fulfilment of the requirements for the degree of Master of Science in Environmental Science at the University of Canterbury /Dewey, Katrina Anne. January 2010 (has links)
Thesis (M. Sc.)--University of Canterbury, 2010. / Typescript (photocopy). Includes bibliographical references (p. [105]-112). Also available via the World Wide Web.
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Resistance to pyrethroid and oxadiazine insecticides in Helicoverpa armigera (Lepidoptera: Noctuidae) populations in Brazil / Resistência de Helicoverpa armigera (Lepidoptera: Noctuidae) a inseticidas dos grupos piretroides e oxadiazinas no BrasilDurigan, Mariana Regina 07 May 2018 (has links)
Helicoverpa armigera (Hübner) was officially reported in Brazil in 2013 causing serious damage to several crops, especially soybean and cotton crops. Because of this severe damage and also because H. armigera is more tolerant to insecticides in compare to other lepidopteran pests in Brazil, there was a significant increase of selection pressure with insecticides in the field. Many cases of insecticide resistance, especially to pyrethroids, have been reported in some countries of the Old World. The main objective of the present study was to characterize the susceptibility of H. armigera and to investigate the mechanisms of its resistance to pyrethroids and indoxacarb in Brazilian populations. Mortality of H. armigera populations was less than 50% when treated with the highest dose of 10 μg a.i./3rd-instar larva of fenvalerate and deltamethrin. Field populations of H. armigera monitored from 2013 to 2016 growing seasons showed mean mortalities of 10 to 40% at the diagnostic dose of 10 μg a.i./3rd-instar larva. The resistance ratio to pyrethroid was 780-fold. The frequency of the chimeric P450 CYP337B3 gene was above 0.95 in all 33 populations screened. The genetic basis of H. armigera resistance to pyrethroids was also investigated. The dominance degree varied from 0.66 to 0.92, i.e., incompletely to completely dominant, and resistance was characterized as autosomal and polygenic. Possible mutations in the sodium channel were investigated, as well as the expression of other P450 genes via RT-qPCR. Two non-synonymous mutations, V937G and Q960H were found, and the genes CYP6AB10, CYP301A, CYP4S13 and CYP321A5 were up-regulated in the Brazilian pyrethroid-resistant strain compared to the susceptible strain. The susceptibility of H. armigera populations to indoxacarb was characterized with a diet overlay bioassay in 3rd-instar larvae. LC50 values ranged from 0.22 (0.16-0.28) μg a.i./cm2 to 0.57 (0.41-0.82) μg a.i./cm2, varying 2.6-fold. The populations were monitored through the 2013-2017 growing seasons, with the diagnostic dose of 6.1 μg a.i./cm2; during the period, the susceptibility to indoxacarb decreased. An indoxacarb-resistant strain was selected under laboratory conditions and showed a resistance ratio of 297.5-fold. These results will contribute to decision-making and implementation of insect resistance-management (IRM) programs in Brazil and other recently invaded countries in Brazil. / Helicoverpa armigera (Hübner) foi reportada oficialmente no Brasil em 2013, ano em que causou grandes perdas em lavouras de soja e algodão no país. Devido ao ataque severo de H. armigera e por ser mais tolerante do que as demais pragas que ocorriam no Brasil, houve um aumento significativo da pressão de seleção com inseticidas no campo. Inúmeros casos de resistência desta praga a inseticidas do grupo dos piretroides já havia sido reportado em alguns países do Velho Mundo. Dentro desse contexto o objetivo desse trabalho foi caracterizar a suscetibilidade e investigar possíveis mecanismos de resistência a piretroides bem como indoxacarb no Brasil. A mortalidade das populações de H. armigera foi menor do que 50 % quando tratadas com a dose máxima de 10 μg i.a./lagarta de 3º instar para fenvalerato e deltametrina. As populações de campo de H. armigera monitoradas entre os anos de 2013 a 2016 na dose diagnóstica de 10 μg i.a./lagarta de 3º instar apresentaram mortalidade de 10 a 40%. A frequência do gene P450 CYP337B3 foi maior do que 0,95 em 33 populações testada. Além disso, as bases genéticas da resistência de H. armigera a piretroides foram investigadas e a razão de resistência com a linhagem suscetível foi de 780 vezes. O grau de dominância variou de 0,66 a 0,92, incompletamente e completamente dominante e a resistência foi caracterizada como autossômica e poligênica. Adicionalmente investigou-se a presença de possíveis mutações no canal de sódio bem como a expressão de outros genes P450 em uma linhagem resistente a piretroides. Foi possível detectar duas mutações não-sinonímias V937G, e Q960H no canal de sódio e os genes CYP6AB10, CYP301A, CYP4S13 e CYP321A5 foram super expressos na linhagem resistente. A suscetibilidade de populações de H. armigera para o inseticida indoxacarb foi caracterizada a partir de bioensaios de ingestão com lagartas de 3° instar. Os valores de CL50 variaram de 0,22 (0,16 - 0,28) μg i.a./cm2 até 0,57 (0,41 - 0,82) μg i.a./cm2 variando em 2,6 vezes. As populações foram monitoradas ao longo das safras agrícolas entre 2013 e 2017 com a concentração diagnóstica de 6,1 μg i.a./cm2 e observou-se uma diminuição na suscetibilidade da praga a indoxacarb. Uma linhagem resistente a indoxacarb foi selecionada em laboratório e comparada com uma linhagem suscetível de referência, apresentando uma razão de resistência de 297,5 vezes. Os resultados obtidos são extremamente importantes e poderão contribuir na tomada de decisões bem como na implementação de programas de manejo da resistência de insetos (MRI) no Brasil.
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Utilization and evaluation of an indoxacarb-based granular bait (Advion) developed for the control of the red imported fire ant, Solenopsis invicta Buren (Hymenoptera: Formicidae)Furman, Barry D. 17 September 2007 (has links)
This research evaluated the new red imported fire ant (RIFA) bait Advionâ¢.
Advion⢠contains the active ingredient indoxacarb which, following ingestion, must be
metabolized into an N-decarbomethoxyllated metabolite known as JT333 in order to
become acutely toxic. Laboratory experimentation was conducted to determine the most
effective chemical form and concentration of indoxacarb, as well as the most appropriate
grit size, for use in Advionâ¢. The results indicated that Advion⢠containing indoxacarb
was more effective than Advion⢠containing JT333, that 0.10%, 0.06%, and 0.045%
were the most effective concentrations of indoxacarb, and that standard sized grit (~2
mm) was more effective than small sized grit (<1 mm).
Field experimentation was conducted to determine the most effective concentration
and quantity of Advionâ¢, as well as the most effective placement of the bait, for
obtaining maximum control of RIFA colonies via individual mound treatments. The
results indicated that 10 g (2 Tbsp) of 0.045% Advion⢠placed around the mound in a
circle with a radius of 0.5-3.0 m was the most effective manner in which to treat
individual RIFA mounds. Field experimentation was also conducted to compare the
effectiveness of label-rate broadcast treatment with Advion⢠to the effectiveness of both label-rate broadcast treatment with Amdroî and pre-baiting broadcast treatment with
Advionâ¢. Both pre-baiting broadcast treatment and label-rate broadcast treatment with
Advion⢠ultimately resulted in 98-99% RIFA colony mortality, which was significantly
greater than the 87% colony mortality resulting from broadcast treatment with Amdroî.
The 6.2 d LT90 for label-rate broadcast treatment with Advion⢠was nearly one half that
of the LT90 for pre-baiting broadcast treatment.
Laboratory experimentation was conducted to determine whether RIFA workers were
capable of metabolizing indoxacarb into the toxic metabolite, and the results clearly
indicated that they were. Finally, field experimentation was conducted to evaluate the
effectiveness of label-rate broadcast treatment with Advion⢠at controlling multiple ant
species. The results indicated that label-rate broadcast treatment with Advion⢠resulted
in control of the RIFA and Pogonomyrmex barbatus for at least 7 wk, and Monomorium
pharaonis and Dorymyrmex pyramicus for some period of time between 3 and 7 wk.
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The Effects of Copper on the Degradation of Atrazine and Indoxacarb in a New Zealand SoilDewey, Katrina Anne January 2010 (has links)
Pesticides are an important component of New Zealand’s primary production sectors. Infestation of pests and diseases can affect crop yield, crop value and damage the country’s export reputation, resulting in economic losses. Repeat applications of pesticides, however, can result in contamination of land and water. Therefore, it is important to understand the fate of pesticides in the environment. Factors which can affect pesticide persistence include soil properties (pH, SOM, CEC), leaching and run-off, volatilisation and co-contamination with heavy metals. Many soils in New Zealand contain high levels of copper from historical applications of copper-based pesticides. Co-contamination of soils may lead to the persistence of some synthetic organic pesticides.
An investigation was undertaken to determine the effects of co-contamination with copper on the biodegradation of atrazine and indoxacarb in a New Zealand soil. A Templeton sandy loam soil was spiked with CuSO₄ to achieve concentrations of 0, 100, 250, 500 and 1000 mg kg⁻¹ Cu. The spiked soils were field aged for six months prior to pesticide spiking with either atrazine or indoxacarb. The aged Cu-spiked soils were spiked with either atrazine or indoxacarb at a rate of 2 mg kg⁻¹. A glasshouse study was conducted to determine if copper inhibited the degradation of the pesticides. The pesticide-spiked soils were sampled at the time of spiking (t₀), at the estimated half-lives (t₁) and at twice the estimated half-lives (t₂) of the individual pesticides. The estimated half-lives were based on literature values.
The bioavailability and subsequent adverse effects of copper on the soil microbial community was investigated. Total and bioavailable copper concentrations, phosphatase and urease enzyme activities, microbial biomass, and pesticide residue concentrations were all measured in the experimental soil. Methods were developed for the extraction of atrazine, atrazine metabolite and indoxacarb residues from the experimental soil.
Total copper concentrations extracted ranged from 4–1060 mg kg⁻¹ in the experimental soils and were consistent throughout the pesticide degradation studies. The bioavailability of copper was a maximum of 2% of the total copper concentration. Bioavailable copper concentrations were positively correlated to total copper (p<0.01).
Soil biological properties were investigated to determine the effects of copper on the soil microbial community. Phosphatase and urease enzyme activities, as well as microbial biomass concentrations, were negatively correlated with total copper (p<0.05). Total copper was a better indicator of effects on microorganisms than bioavailable copper. The soil biological properties began showing adverse effects above a total copper concentration of 100 mg kg⁻¹. This concentration also corresponds to New Zealand’s copper limit in biosolids, which is protective of human, plant and microorganism health.
Phosphate buffer extraction methods were developed for the analysis of atrazine and indoxacarb residues in the experimental soil by HPLC-UV. Elevated copper concentrations did not inhibit the degradation of atrazine or indoxacarb in the experimental soil. The half-lives of both atrazine (≤19.4 d) and indoxacarb (≤18.8 d) were lower in the spiked experimental soils than the means reported in previous New Zealand and international studies, but were within the reported ranges. This study provided the first data on the fate of indoxacarb in New Zealand.
Hydroxyatrazine was the only metabolite detected in the atrazine-spiked experimental soils. Significant differences between the control (Cu-1) and copper levels above 100 mg kg⁻¹ were observed for hydroxyatrazine at t₂. Significant negative correlations were observed between hydroxyatrazine and the microbiomass at t₁ and phosphatase activity at t₂ (p<0.05). These significant relationships suggest that elevated copper concentrations may alter the degradation of this metabolite in the experimental soils due copper toxicity of the soil microbial community.
The results of this thesis indicate that elevated levels of copper above 100 mg kg⁻¹ negatively impact the soil microbial community and may reduce the overall health of the soil. Biodegradation is a key mechanism for the degradation of atrazine and indoxacarb in the soil, so it is important that the health of the soil microbial community is maintained. Therefore, it is recommended that atrazine and indoxacarb are only applied to soils with a total copper concentration less than 100 mg kg⁻¹. This will protect the health of the soil microbial community and prevent the potential adverse effects of copper on the degradation of pesticide metabolites in the soil.
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The Effects of Copper on the Degradation of Atrazine and Indoxacarb in a New Zealand SoilDewey, Katrina Anne January 2010 (has links)
Pesticides are an important component of New Zealand’s primary production sectors. Infestation of pests and diseases can affect crop yield, crop value and damage the country’s export reputation, resulting in economic losses. Repeat applications of pesticides, however, can result in contamination of land and water. Therefore, it is important to understand the fate of pesticides in the environment. Factors which can affect pesticide persistence include soil properties (pH, SOM, CEC), leaching and run-off, volatilisation and co-contamination with heavy metals. Many soils in New Zealand contain high levels of copper from historical applications of copper-based pesticides. Co-contamination of soils may lead to the persistence of some synthetic organic pesticides. An investigation was undertaken to determine the effects of co-contamination with copper on the biodegradation of atrazine and indoxacarb in a New Zealand soil. A Templeton sandy loam soil was spiked with CuSO₄ to achieve concentrations of 0, 100, 250, 500 and 1000 mg kg⁻¹ Cu. The spiked soils were field aged for six months prior to pesticide spiking with either atrazine or indoxacarb. The aged Cu-spiked soils were spiked with either atrazine or indoxacarb at a rate of 2 mg kg⁻¹. A glasshouse study was conducted to determine if copper inhibited the degradation of the pesticides. The pesticide-spiked soils were sampled at the time of spiking (t₀), at the estimated half-lives (t₁) and at twice the estimated half-lives (t₂) of the individual pesticides. The estimated half-lives were based on literature values. The bioavailability and subsequent adverse effects of copper on the soil microbial community was investigated. Total and bioavailable copper concentrations, phosphatase and urease enzyme activities, microbial biomass, and pesticide residue concentrations were all measured in the experimental soil. Methods were developed for the extraction of atrazine, atrazine metabolite and indoxacarb residues from the experimental soil. Total copper concentrations extracted ranged from 4–1060 mg kg⁻¹ in the experimental soils and were consistent throughout the pesticide degradation studies. The bioavailability of copper was a maximum of 2% of the total copper concentration. Bioavailable copper concentrations were positively correlated to total copper (p<0.01). Soil biological properties were investigated to determine the effects of copper on the soil microbial community. Phosphatase and urease enzyme activities, as well as microbial biomass concentrations, were negatively correlated with total copper (p<0.05). Total copper was a better indicator of effects on microorganisms than bioavailable copper. The soil biological properties began showing adverse effects above a total copper concentration of 100 mg kg⁻¹. This concentration also corresponds to New Zealand’s copper limit in biosolids, which is protective of human, plant and microorganism health. Phosphate buffer extraction methods were developed for the analysis of atrazine and indoxacarb residues in the experimental soil by HPLC-UV. Elevated copper concentrations did not inhibit the degradation of atrazine or indoxacarb in the experimental soil. The half-lives of both atrazine (≤19.4 d) and indoxacarb (≤18.8 d) were lower in the spiked experimental soils than the means reported in previous New Zealand and international studies, but were within the reported ranges. This study provided the first data on the fate of indoxacarb in New Zealand. Hydroxyatrazine was the only metabolite detected in the atrazine-spiked experimental soils. Significant differences between the control (Cu-1) and copper levels above 100 mg kg⁻¹ were observed for hydroxyatrazine at t₂. Significant negative correlations were observed between hydroxyatrazine and the microbiomass at t₁ and phosphatase activity at t₂ (p<0.05). These significant relationships suggest that elevated copper concentrations may alter the degradation of this metabolite in the experimental soils due copper toxicity of the soil microbial community. The results of this thesis indicate that elevated levels of copper above 100 mg kg⁻¹ negatively impact the soil microbial community and may reduce the overall health of the soil. Biodegradation is a key mechanism for the degradation of atrazine and indoxacarb in the soil, so it is important that the health of the soil microbial community is maintained. Therefore, it is recommended that atrazine and indoxacarb are only applied to soils with a total copper concentration less than 100 mg kg⁻¹. This will protect the health of the soil microbial community and prevent the potential adverse effects of copper on the degradation of pesticide metabolites in the soil.
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Resistência de populações pernambucanas de traças-das-crucíferas, Plutella xylostella (L.,1758) (Lepidoptera : Plutellidae) a inseticidas / Resistance of Diamonback moth, Plutella xylostella (L.,1758) (Lepidoptera : Plutellidae) populations from Pernambuco state to insecticidesSANTOS, Vanessa Corrêa 01 February 2010 (has links)
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Previous issue date: 2010-02-01 / Plutella xylostella (L.) (Lepidoptera: Plutellidae), popularly known as diamondback moth, is a major pest of brassicaceae crops (e.g., kale, cauliflower, broccoli, and cabbage) throughout the world. Several insecticides have been intensively used during several cultivation cycles and, even in some areas, up to 15 to 20 applications per season have been observed. Besides the problems they may cause to human and environmental health, the frequent use of these products has been associated to the evolution of resistance in P. xylostella populations to various insecticides such as the pyrethroids, carbamates, organophosphates, and even Bacillus thuringiensis. The current study objective was to identify the resistance in P. xylostella populations from Pernambuco State, when exposed to abamectin, methomyl, lufenuron, indoxacarb, and diafentiuron. Concentration-response regressions were established using 2nd-instar larvae of P. xylostella. All P. xylostella populations showed significant resistance ratio (RR) to at least one insecticide. The smallestCL50s values were estimated for abamectin, which varied from 0.01 to 0.74 mg/L and the highest CL50s were estimated for diafentiuron, which varied from 47.9 to 122.2 mg/L. The Bezerro County population presented the highest resistance ratios to indoxacarb (25.3-fold), abamectin (61.7-fold), and lufenuron (705.2-fold), compared to the reference population. TheBonito and Jupi Counties populations were 33.0- and 12.0-times more resistant to lufenuron and abamectina, respectively. These results demonstrate that intensive and indiscriminate use of insecticides in Pernambuco must be a concern, which suggests the immediate establishment of a resistance management program associated to integrated pest management in these areas. / Plutella xylostella (L.) (Lepidoptera: Plutellidae), conhecida popularmente como traça-das-crucíferas é considerada a principal praga do cultivo de brássicas (ex: couve, couve-flor, brócolis e repolho) em todo o mundo. Diversos inseticidas têm sido utilizados intensivamente durante o ciclo da cultura, e em algumas áreas já foram detectadas 15 a 20 aplicações por ciclo. Além dos problemas gerados à saúde do agricultor e ao meio ambiente, o uso excessivo desses produtos tem proporcionado o aparecimento de populações resistentes deste inseto-praga a diversos compostos químicos, como é o caso dos inseticidas piretróides, carbamatos, organofosforados e Bacillus thuringiensis. O presente estudo teve como objetivo identificar a resistência em populações de P. xylostella do Estado de Pernambuco, utilizando os inseticidas abamectina, metomil, lufenurom, diafentiuron e indoxacarbe. Curvas de concentração-resposta foram estabelecidas usando lagartas de 2º instar de P. xylostella. Todas as populações pernambucanas de P. xylostella apresentaram razão de resistência (RR) significativa a pelomenos um inseticida. As menores CL50s foram registradas para o inseticida abamectina, variando de 0,01 a 0,74 mg/L e as maiores CL50s foram para o inseticida diafentiuron, 47,9 a 122,2 mg/L. A população do município de Bezerros apresentou as maiores razões de resistência 25,3 a indoxacarbe, 61,7 a abamectina e 705,2 a lufenurom, quando comparadas àpopulação suscetível. A população do município de Bonito apresentou uma razão de resistência 33,0 a lufenurom e Jupi 12,0 para abamectina. Estes resultados demonstram que o uso intensivo e indiscriminado de inseticidas na região Agreste de Pernambuco é preocupante, sugerindo o estabelecimento de um programa de manejo da resistência associado ao manejo integrado de pragas nesta área.
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Rezistence škůdců řepky k vybraným účinným látkám insekticidůHajda, Tomáš January 2018 (has links)
Resistence population of pollen beattle on selected locations of Moravia and Silesia were observed during the 2017. Beattles were taked off in the field during spring and their sensitivity to insecticides active substances indoxacarb, chlorpyrifos, thiacloprid, tau-fluvalinate, cypermethrin and lambda-cyhalothrin were tested in laboratory. Tested using methods of IRAC – 11, 21, 25 and 27. Mortality of beattles at various concentrations of active substances was evaluated after 24 hours. Levels of resistance were changed for individual location.
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The study of resistance to insecticide active ingredients in relation to population size in the German cockroach (Blattella germanica)Madison Patricia Gits (12476766) 28 April 2022 (has links)
<p>The German cockroach (<em>Blattella germanica</em>) is one of the most critical urban pests globally due to the health risks, such as asthma, it imposes on people. Insecticides are known to manage their large population sizes, but the rapid rate at which cockroaches develop resistance is a continuing problem. This can be expensive and time-consuming for both the consumer and the pest management professional (PMP) applying the treatment. Each cockroach population is unique because different strains have different resistance profiles, so resistance profiles must be considered. This thesis addressed this little-studied issue in a controlled laboratory setting. Cockroach strains from Indianapolis, Indiana, Danville, Illinois, and Baltimore, Maryland, were used. Fifteen insecticide active ingredients most used by consumers and PMPs were selected for testing in vial bioassays to establish resistance profiles. No choice and choice feeding assays with four currently registered bait products were performed to assess the impacts of competing food and circadian rhythms on bait resistance levels. Selected population growth characteristics were compared in virgin females and nymphs in each cockroach strain to determine if certain population traits were associated with insecticide resistance. The results indicate that emamectin benzoate is the most effective active ingredient in causing the highest mortality in all strains in vial bioassays. No choice assays confirmed vial assay results the best, with Optigard (emamectin benzoate) being the most effective bait in all strains. The time a female carries its egg case and takes for a nymph to become an adult was significantly different across all strains, suggesting possible fitness costs for higher-level multi-resistance. The results acquired from these studies can help develop rapid tests to use in the field based on the no choice feeding assay while also adding more information supporting current resistance and cross-resistance evolution theories.</p>
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Avaliação da Mutagenicidade do Indoxacarbe em Ratos e Gatos / Mutagenicity Assessment of Indoxacarb in Rats and CatsSilva, Dayane Aparecida Francisco da 16 September 2015 (has links)
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Previous issue date: 2015-09-16 / Background: Pesticides are substances used for pest control. Because of their persistence in the environment, they can induce toxicity in humans and animals. Indoxacarb is an oxadiazine insecticide that acts against insects of the order Lepidoptera. Furthermore, indoxacarb has demonstrated strong insecticide activity against fleas; therefore, it is used in ectoparasite treatment. Choice of species used in this study (rats and cats) is based on several factors such as these animals have a high count of micronucleated polychromatic erythrocytes, thereby facilitating the execution of the chosen assay; rats are the standard animal model for mutagenicity studies; and the product is intended for use in cats. Limited data in literature pertaining to the mutagenic effects of this product motivated this study. The aim of this study was to evaluate the mutagenicity of indoxacarb when administered in one and tenfold therapeutic doses in rats and cats. This evaluation was performed using the micronucleus test. Materials, Methods & Results: Forty male Wistar rats aged 70 days and weighing 280 ± 10 g and 20 mixed breed male and female adult cats weighing 4 ± 0.2 kg were selected. These animals were obtained from the central animal facility and cattery, respectively, of the university of origin. Rats were reared in individual cages with a controlled temperature of 22°C ± 2°C, humidity of 55% ± 5% and 12-h light dark cycle. Cats were reared in individual stalls with water and food ad libitum. Animals were randomly distributed into four groups comprising 10 rats and 5 cats in respective groups: negative control group, which received 0.9% sodium chloride solution as a single topical administration; positive control group, which received 50 mg/kg cyclophosphamide as a single intra-peritoneal (rats) or intravenous injection (cats); indoxacarb group, which received indoxacarb as a single topical dose according to the manufacturer s recommendations; and high dose indoxacarb group, which also received indoxacarb in a single topical dose, but at a tenfold concentration. Rats were evaluated 24 h after indoxacarb administration. After euthanasia, rat femurs were obtained and their medullary canals were washed using fetal bovine serum. The content was centrifuged and used for smear preparations. Cats were evaluated using the micronucleus test before and 24 h after indoxacarb administration. For smear preparations, a drop of peripheral blood samples was obtained from the tail tip. Smear fixation, staining, and microscopic analysis were similar for cats and rats. Statistical analyses were performed using analysis of variance with contrast through Tukey s method and paired t test to compare time points. The significance level was 5%. Indoxacarb showed no mutagenic activity in the two species and doses evaluated. Even in animals subjected to high doses, the micronuclei count remained within the normal range (p > 0.05). Discussion: The results of this study corroborate those of other studies, where in the mutagenic capacity of indoxacarb was similar in different animal species and product delivery routes. In addition, it is of note the speed and ease of micronucleus testing, which makes it an important mutagenicity bioassay. / Introdução: Os pesticidas são venenos intencionalmente dispersos no ambiente para o controle de pragas e, com sua persistência nesse meio podem induzir a toxicidade em seres humanos e animais. Indoxacarbe é um inseticida, oxidiazínico, que apresenta atividade sobre insetos da ordem lepidóptera. No tratamento contra pulgas em pequenos animais, o indoxacarbe tem demonstrado uma alta atividade inseticida associada a esses ectoparasitas. A escolha da utilização dessas duas espécies animais neste estudo se deu pelo fato de que ratos e gatos apresentam uma grande quantidade de eritrócitos policromáticos micronucleados, facilitando desta forma a realização do ensaio escolhido e, pelo rato ser o modelo biológico padrão para avaliações de mutagenicidade, e por fim pelo fato do produto ser indicado para o uso em gatos. A escassez na literatura sobre o efeito mutagênico causado pelo uso desse produto levou a realização dessa pesquisa, cujo objetivo foi avaliar por meio do teste de micronúcleo a mutagenicidade do indoxacarbe em dose terapêutica e em dez vezes maior em ratos e gatos. Materiais, métodos e resultados: Foram selecionados 40 ratos, com 70 dias de idade, da linhagem Wistar, machos, peso de 280g±10 e 20 gatos adultos, sem raça definida, machos e fêmeas, com peso de 4kg±200gr, ambos do biotério central e gatil da universidade de origem, respectivamente. Os ratos foram mantidos em caixas individuais em ambiente com controle de temperatura 22ºC±2, umidade 55%±5, fotoperíodo 12 horas claro e escuro, os gatos foram mantidos em baias individuais, e ambos com água e ração ad libitum. Os animais foram distribuídos aleatoriamente em quatro grupos, com 10 animais em cada grupo de ratos e 5 animais nos grupos compostos por gatos, e foram tratados com: Grupo controle negativo (GCN)-solução de cloreto de sódio 0,9% por via tópica, em dose única. Grupo controle positivo (GCP)-ciclofosfamida em única dose de 50mg/kg por via intraperitoneal nos ratos e intravenosa nos gatos. Grupo indoxacarbe (GI)- indoxacarbe por via tópica, em dose única recomendado pelo fabricante. Grupo indoxacarbe dose alta (GIDA)-indoxacarbe por via tópica, em dose única, porém dez vezes maior que a dose recomendada pelo fabricante. Os ratos foram avaliados 24 horas após o uso do indoxacarbe, após eutanásia e retirada do fêmur para a realização da lavagem do canal medular com soro fetal bovino, posterior centrifugação, retirada do sobrenadante e realização do esfregaço. Os gatos foram avaliados por meio do teste de micronúcleo antes e 24 horas após a aplicação do indoxacarbe, através da coleta de uma gota de sangue periférico da extremidade do rabo para a realização do esfregaço. A fixação, coloração e leitura das lâminas foram semelhantes para os ratos e gatos. Os testes estatísticos utilizados foram de análise de variância com contraste pelo método de Tukey e, para a comparação entre momentos utilizou-se teste t pareado. O nível de significância adotado foi de 5%. Indoxacarbe não apresentou atividade mutagênica em nenhuma das espécies e doses estudadas, mesmo nos animais submetidos a altas doses, a quantidade de micronúcleos permaneceu dentro da normalidade (p>0,05).Discussão: Os resultados obtidos neste estudo corroboraram com os poucos relatos encontrados na literatura, afirmando a ausência da capacidade mutagênica do indoxacarbe em diferentes espécies animais e vias de administração do produto. Observou-se também a rapidez, e facilidade na realização do teste para micronúcleo, caracterizando-o como um importante bioensaio para avaliações de mutagenicidade.
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