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2.
Insects ; 13(11)2022 Oct 26.
Article de Anglais | MEDLINE | ID: mdl-36354804

RÉSUMÉ

The behavior of bees is modulated by the presence of other bees and potentially by the visual information transmitted by the different body positions of bees while visiting flowers. We tested whether bee body position promoted the attraction and/or antagonistic behavior of con- and hetero-specific bees that interacted on prickly pear flowers of Opuntia huajuapensis. To test this, we placed dummy model bees of Apis mellifera and the native Lithurgus littoralis in flowers in three common body positions: alert, feeding, and horizontal. The results showed that dummy model bees in feeding and horizontal body positions attracted A. mellifera bees, while the alert position attracted native male L. littoralis. Male L. littoralis bees spent more time attacking model bees in horizontal and alert positions. The position of dummy bees also influenced response times. Bees of A. mellifera responded fastest to L. littoralis in the alert and horizontal position, male L. littoralis responded fastest to con-specific bees in the alert and feeding position, and female L. littoralis responded fastest to A. mellifera bees in the feeding position. A. mellifera reacted fastest to their con-specific bees in the alert and horizontal body positions. Our results demonstrate, for the first time in bees, that the position of individuals on a floral resource provides important visual information that modulates bee behavior, and illuminates aspects that likely have implications for bees in access to floral resources.

3.
Anim Cogn ; 25(1): 63-72, 2022 Feb.
Article de Anglais | MEDLINE | ID: mdl-34302566

RÉSUMÉ

The ability to learn in the context of predation allows prey to respond to threats by adjusting their behavior based on specific information acquired from their current environment. Habituation is a process that allows animals to adapt to environmental changes. Very little is known about habituation in wild animals in general and there are no studies on habituation in anuran tadpoles in particular. Here, we performed three experiments to investigate the behavioral response of predator naïve Pleurodema thaul tadpoles to repeated stimulation with two predation risk cues (injured conspecific and predator fed cues) which a priori provide different information regarding risk. Experiment 1 showed that P. thaul tadpoles habituate the antipredator response when undergo predation risk chemical cues from injured conspecific and that response is long term. Experiment 2 showed that P. thaul tadpoles did not habituate their antipredator response when exposed to cues derived from an event of nymph odonate preying on P. thaul tadpoles (predator fed cues). Experiment 3 specifically evaluated the risk imposed by each of the risk cues used in Experiment 1 and Experiment 2 and showed that the degree of perceived risk in tadpoles appear to be similar in a single experience with any risk stimuli. We suggest that the behavioral habituation of tadpoles in the context of predation could be modulated by the level of uncertainty associated with risk stimuli.


Sujet(s)
Habituation , Comportement prédateur , Animaux , Anura/physiologie , Signaux , Larve/physiologie , Comportement prédateur/physiologie , Incertitude
4.
Ci. Rural ; 51(5)2021. ilus, graf, tab
Article de Anglais | VETINDEX | ID: vti-31290

RÉSUMÉ

This article combines influencing factors of farmers participation in the Rural Living Environment Renovation Project (RLERP) and conceptualizes a model that depicts the relationships between the demographic characteristics of farmers and their perceptions and behavioral response to RLERP. Using a questionnaire survey to collect empirical data, we found (1) A total of 92% of farmers have fully realized the importance of rural living environment, but most people have adopted a wait-and-see attitude and a lack of motivation to participate. (2) A total of 65% of farmers participate in the collection and classification of domestic waste, 22% of the farmers participate in captivity livestock behavior, and 19% of farmers participate in the response behavior of domestic sewage treatment. (3) A significant positive correlation occurs between income level and farmers cognition and behavior response. (4) The education standards of the public are not correlated with the farmers cognition but is significantly correlated with farmers behavioral response. (5) The cognitive and behavioral response of females to RLERP is significantly higher than that of men. 6) In the process from cognition to the action response, farmers cognition is positively correlated with action response. On this basis, some measures and suggestions to improve the response of farmers to rural living environment renovation are put forward.(AU)


Este artigo combina fatores que influenciam a participação dos agricultores no Projeto de Renovação do Ambiente Rural (RLERP) e conceitua um modelo que descreve as relações entre as características demográficas dos agricultores e suas percepções e resposta comportamental ao RLERP. Usando uma pesquisa por questionário para coletar dados empíricos, encontramos: (1) um total de 92% dos agricultores perceberam plenamente a importância do ambiente de vida rural, mas a maioria das pessoas adotou uma atitude de esperar para ver e uma falta de motivação para participar; (2) um total de 65% dos agricultores participam da coleta e classificação do lixo doméstico, 22% dos agricultores participam do comportamento pecuário em cativeiro e 19% dos agricultores participam do comportamento de resposta ao tratamento de esgoto doméstico; (3) uma correlação positiva significativa ocorre entre o nível de renda, a cognição e a resposta comportamental dos agricultores; (4) os padrões de educação do público não estão correlacionados com a cognição dos agricultores, mas estão significativamente correlacionados com a resposta comportamental dos agricultores; (5) a resposta cognitiva e comportamental das mulheres ao RLERP é significativamente maior do que a dos homens; (6) no processo de cognição para resposta de ação, a cognição dos agricultores está positivamente correlacionada com a resposta de ação. Com base nisso, são apresentadas algumas medidas e sugestões para melhorar a resposta dos agricultores à renovação do ambiente rural.(AU)


Sujet(s)
Qualité de vie , Comportement
5.
Ciênc. rural (Online) ; 51(5): e20200847, 2021. tab, graf
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1153897

RÉSUMÉ

ABSTRACT: This article combines influencing factors of farmers' participation in the Rural Living Environment Renovation Project (RLERP) and conceptualizes a model that depicts the relationships between the demographic characteristics of farmers and their perceptions and behavioral response to RLERP. Using a questionnaire survey to collect empirical data, we found (1) A total of 92% of farmers have fully realized the importance of rural living environment, but most people have adopted a wait-and-see attitude and a lack of motivation to participate. (2) A total of 65% of farmers participate in the collection and classification of domestic waste, 22% of the farmers participate in captivity livestock behavior, and 19% of farmers participate in the response behavior of domestic sewage treatment. (3) A significant positive correlation occurs between income level and farmers' cognition and behavior response. (4) The education standards of the public are not correlated with the farmers' cognition but is significantly correlated with farmers' behavioral response. (5) The cognitive and behavioral response of females to RLERP is significantly higher than that of men. 6) In the process from cognition to the action response, farmers' cognition is positively correlated with action response. On this basis, some measures and suggestions to improve the response of farmers to rural living environment renovation are put forward.


RESUMO: Este artigo combina fatores que influenciam a participação dos agricultores no Projeto de Renovação do Ambiente Rural (RLERP) e conceitua um modelo que descreve as relações entre as características demográficas dos agricultores e suas percepções e resposta comportamental ao RLERP. Usando uma pesquisa por questionário para coletar dados empíricos, encontramos: (1) um total de 92% dos agricultores perceberam plenamente a importância do ambiente de vida rural, mas a maioria das pessoas adotou uma atitude de esperar para ver e uma falta de motivação para participar; (2) um total de 65% dos agricultores participam da coleta e classificação do lixo doméstico, 22% dos agricultores participam do comportamento pecuário em cativeiro e 19% dos agricultores participam do comportamento de resposta ao tratamento de esgoto doméstico; (3) uma correlação positiva significativa ocorre entre o nível de renda, a cognição e a resposta comportamental dos agricultores; (4) os padrões de educação do público não estão correlacionados com a cognição dos agricultores, mas estão significativamente correlacionados com a resposta comportamental dos agricultores; (5) a resposta cognitiva e comportamental das mulheres ao RLERP é significativamente maior do que a dos homens; (6) no processo de cognição para resposta de ação, a cognição dos agricultores está positivamente correlacionada com a resposta de ação. Com base nisso, são apresentadas algumas medidas e sugestões para melhorar a resposta dos agricultores à renovação do ambiente rural.

6.
Ci. Rural ; 50(9): e20190326, July 10, 2020. tab
Article de Anglais | VETINDEX | ID: vti-28784

RÉSUMÉ

The present study aimed to evaluate changes in the locomotor activity of diamondback moth (Plutella xylostella) populations exposed to surfaces treated with the insecticide chlorantraniliprole under laboratory conditions. Diamondback moth populations from municipalities incorrectly using the insecticide [Camocim de São Félix, PE (CSF); Sairé, PE (SR); and Lajedo, PE (LJ)] and two laboratory populations from Recife, PE (RCF), and Viçosa, MG (VÇS) were exposed to dry insecticide residues in increasing concentrations. The following behavioral parameters of the populations were analyzed: walking time (WT), mean walking speed (MWS), and rest time (RT). Regarding RT, the SR and CSF populations demonstrated a behavior of irritability and increased WT with increased exposure concentration. The RCF population presented a contrasting response. The MWS values in the SR and CSF populations showed a decreasing trend with increased exposure concentration. The LJ and RCF populations showed no changes in terms of MWS. The RT values in the SR population decreased with increased insecticide concentration. In general, the SR and CSF populations presented a behavioral pattern different from that of laboratory populations. The changes in locomotor activity observed may result in lower control efficacy of the insecticide due to repellency or escape of insects. Regarding the effect of insecticide concentrations used in the populations, a defined pattern was not observed, and the effect alternated between an increase, a decrease, and an undefined pattern for the variables studied.(AU)


O presente estudo teve por objetivo averiguar, em condições de laboratório, alterações na atividade locomotora de populações de traça-das-crucíferas, expostas a superfícies tratadas com o inseticida clorantraniliprole. Populações de Plutella xylostella provenientes dos municípios com uso inadequado de inseticida: Camocim de São Félix-PE (CSF), Sairé-PE (SR), Lajedo-PE (LJ) e duas populações de laboratório: Recife-PE (RCF) e Viçosa-MG (VÇS) foram expostas a resíduos secos do inseticida, em concentrações crescentes. Estas populações tiveram os seguintes parâmetros comportamentais analisados: Tempo de caminhamento (TC), Velocidade Média de caminhamento (VMC) e Tempo de Repouso (TR). Com relação ao TC, as populações de SR e CSF demonstraram comportamento de irritabilidade, aumentando o tempo de caminhamento com o aumento da concentração de exposição. A população de RCF apresentou resposta contrária. Em relação ao parâmetro VMC, as populações de SR e CSF apresentaram tendência de redução nos valores com o aumento da concentração de exposição. As populações de LJ e RCF não apresentaram mudanças deste comportamento. Para a variável TR, a população de SR apresentou redução nesses valores, com o aumento da concentração do inseticida. De forma geral, as populações de SR e CSF apresentaram um padrão de comportamento diferente das populações de laboratório. Estas alterações na atividade locomotora podem resultar numa menor eficácia de controle do inseticida devido à irritabilidade ou fuga. Quanto ao efeito das concentrações usadas do inseticida entre populações, de forma geral, não foi possível observar um padrão definido, tendo este efeito alternado entre aumento, redução e padrão não definido para as variáveis estudadas.(AU)


Sujet(s)
Animaux , Lepisma/effets des médicaments et des substances chimiques , Brassicaceae , Locomotion/effets des médicaments et des substances chimiques , Insecticides/administration et posologie
7.
PeerJ ; 8: e8718, 2020.
Article de Anglais | MEDLINE | ID: mdl-32185111

RÉSUMÉ

In this study, we explored chemosensory, ingestive and prey-catching responses of neonate Mexican Black-bellied Gartersnakes (Thamnophis melanogaster) to crayfish (Cambarellus montezumae). By comparing snakes from a recently discovered crayfish-eating population and a typical non-crayfish-eating population, we asked which behavioral components change as a species enlarges its feeding niche. In the crayfish-eating population chemosensory responsiveness to crayfish was not enhanced but its heritability was higher. Neonates of both populations showed similar preference for freshly-molted versus unmolted crayfish, and whereas the tendency to ingest both crayfish stages remained stable between ages 15 and 90 days in the non-crayfish-eating population, in the crayfish-eating population it actually decreased. Techniques to catch and manipulate molted crayfish were similar in the two populations. We discuss the possibility that there is no increase in the behavioral response to eat crayfish by the neonates of the crayfish-eating populations, possibly due to the absence of ecological and spatial isolation between the two T. melanogaster populations. The crayfish ingestion in some population of T. melanogaster can be explained by environmental differences between populations, or by recent origin of crayfish ingestion in T. melanogaster.

8.
Mammalia ; 84(3): 227-238, 2020.
Article de Anglais | MEDLINE | ID: mdl-34290454

RÉSUMÉ

Small mammal communities in the Neotropics are composed largely of sigmodontine rodents. However, many questions regarding these communities remain unanswered, especially those pertaining to fine-scale sympatry and habitat selection. To address this, we examined sigmodontine community structure and vegetation in the western margin of the Upper Paraná Atlantic Forest and the southwestern-most extent of the Cerrado (CE) (an extensive South American savanna ecoregion) of Paraguay. Vegetation classifications were derived from satellite imagery combined with maps based on extensive ground-based surveys. The three most abundant species (Akodon montensis, Hylaeamys megacephalus, and Oligoryzomys nigripes) were found most often in microsympatry with conspecifics, and were negatively associated with other species. Akodon montensis was associated with high forest (HF), and H. megacephalus with bamboo understory (BU), whereas O. nigripes did not exhibit a habitat preference. The first two species' distributions within the landscape were found to be driven primarily by habitat selection, and O. nigripes by a behavioral response (avoidance) to the presence of the other two species. Moreover, habitat influences whether or not a particular species associates with, or avoids, conspecifics or other species.

9.
Rev. bras. ciênc. avic ; 22(3): eRBCA, out. 2020. tab
Article de Anglais | VETINDEX | ID: biblio-1490793

RÉSUMÉ

The present study was planned to evaluate the growth performance, morphometrics, physiological and behavioral response of Naked Neck chicken under different production systems and nutritional regimens. For this, a total of 900 Naked Neck chickens of 6-weeks of age were used; the birds were divided into 10 treatment groups consisting of 5 replicates of 18 birds each. A 2×5 factorial arrangement of treatment was employed under Completely Randomized Design. Treatments were consisted of two production systems (intensive and free range) and five nutritional regimens (100% commercial feed, 75% commercial feed +25% kitchen waste, 50% commercial feed +50% kitchen waste, 25% commercial feed +75% kitchen waste and 100% kitchen waste). Body weight, heartbeat and respiration rate were higher in birds reared under intensive system and spent most of their time sitting whereas higher feed intake and increased pecking behavior were noted in birds reared under free range system. Regarding feeding regimens, higher feed intake, cloacal temperature, body and neck length were observed in birds fed with 100% kitchen waste whereas higher drumstick, shank and wing spread were observed in birds fed under 100% commercial feed. Furthermore, higher shank and neck length were observed in birds fed 75% kitchen waste and higher body weight was observed in birds fed 50% kitchen waste. Significant interactions were also observed regarding feed intake, cloacal temperature, drumstick circumference, shank length, feeding, sitting and walking behavior. In conclusion, Naked Neck chicken perform better in free range system whereas feeding kitchen waste up to 50% may enhance growth, morphometric, physiological traits and improve behavioral response.


Sujet(s)
Animaux , Poulets/croissance et développement , Poulets/physiologie , Poulets/métabolisme , Compléments alimentaires
10.
R. bras. Ci. avíc. ; 22(3): eRBCA-2020-1303, out. 2020. tab
Article de Anglais | VETINDEX | ID: vti-761967

RÉSUMÉ

The present study was planned to evaluate the growth performance, morphometrics, physiological and behavioral response of Naked Neck chicken under different production systems and nutritional regimens. For this, a total of 900 Naked Neck chickens of 6-weeks of age were used; the birds were divided into 10 treatment groups consisting of 5 replicates of 18 birds each. A 2×5 factorial arrangement of treatment was employed under Completely Randomized Design. Treatments were consisted of two production systems (intensive and free range) and five nutritional regimens (100% commercial feed, 75% commercial feed +25% kitchen waste, 50% commercial feed +50% kitchen waste, 25% commercial feed +75% kitchen waste and 100% kitchen waste). Body weight, heartbeat and respiration rate were higher in birds reared under intensive system and spent most of their time sitting whereas higher feed intake and increased pecking behavior were noted in birds reared under free range system. Regarding feeding regimens, higher feed intake, cloacal temperature, body and neck length were observed in birds fed with 100% kitchen waste whereas higher drumstick, shank and wing spread were observed in birds fed under 100% commercial feed. Furthermore, higher shank and neck length were observed in birds fed 75% kitchen waste and higher body weight was observed in birds fed 50% kitchen waste. Significant interactions were also observed regarding feed intake, cloacal temperature, drumstick circumference, shank length, feeding, sitting and walking behavior. In conclusion, Naked Neck chicken perform better in free range system whereas feeding kitchen waste up to 50% may enhance growth, morphometric, physiological traits and improve behavioral response.(AU)


Sujet(s)
Animaux , Poulets/croissance et développement , Poulets/métabolisme , Poulets/physiologie , Compléments alimentaires
11.
Ciênc. rural (Online) ; 50(9): e20190326, 2020. tab
Article de Anglais | LILACS-Express | LILACS | ID: biblio-1133313

RÉSUMÉ

ABSTRACT: The present study aimed to evaluate changes in the locomotor activity of diamondback moth (Plutella xylostella) populations exposed to surfaces treated with the insecticide chlorantraniliprole under laboratory conditions. Diamondback moth populations from municipalities incorrectly using the insecticide [Camocim de São Félix, PE (CSF); Sairé, PE (SR); and Lajedo, PE (LJ)] and two laboratory populations from Recife, PE (RCF), and Viçosa, MG (VÇS) were exposed to dry insecticide residues in increasing concentrations. The following behavioral parameters of the populations were analyzed: walking time (WT), mean walking speed (MWS), and rest time (RT). Regarding RT, the SR and CSF populations demonstrated a behavior of irritability and increased WT with increased exposure concentration. The RCF population presented a contrasting response. The MWS values in the SR and CSF populations showed a decreasing trend with increased exposure concentration. The LJ and RCF populations showed no changes in terms of MWS. The RT values in the SR population decreased with increased insecticide concentration. In general, the SR and CSF populations presented a behavioral pattern different from that of laboratory populations. The changes in locomotor activity observed may result in lower control efficacy of the insecticide due to repellency or escape of insects. Regarding the effect of insecticide concentrations used in the populations, a defined pattern was not observed, and the effect alternated between an increase, a decrease, and an undefined pattern for the variables studied.


RESUMO: O presente estudo teve por objetivo averiguar, em condições de laboratório, alterações na atividade locomotora de populações de traça-das-crucíferas, expostas a superfícies tratadas com o inseticida clorantraniliprole. Populações de Plutella xylostella provenientes dos municípios com uso inadequado de inseticida: Camocim de São Félix-PE (CSF), Sairé-PE (SR), Lajedo-PE (LJ) e duas populações de laboratório: Recife-PE (RCF) e Viçosa-MG (VÇS) foram expostas a resíduos secos do inseticida, em concentrações crescentes. Estas populações tiveram os seguintes parâmetros comportamentais analisados: Tempo de caminhamento (TC), Velocidade Média de caminhamento (VMC) e Tempo de Repouso (TR). Com relação ao TC, as populações de SR e CSF demonstraram comportamento de irritabilidade, aumentando o tempo de caminhamento com o aumento da concentração de exposição. A população de RCF apresentou resposta contrária. Em relação ao parâmetro VMC, as populações de SR e CSF apresentaram tendência de redução nos valores com o aumento da concentração de exposição. As populações de LJ e RCF não apresentaram mudanças deste comportamento. Para a variável TR, a população de SR apresentou redução nesses valores, com o aumento da concentração do inseticida. De forma geral, as populações de SR e CSF apresentaram um padrão de comportamento diferente das populações de laboratório. Estas alterações na atividade locomotora podem resultar numa menor eficácia de controle do inseticida devido à irritabilidade ou fuga. Quanto ao efeito das concentrações usadas do inseticida entre populações, de forma geral, não foi possível observar um padrão definido, tendo este efeito alternado entre aumento, redução e padrão não definido para as variáveis estudadas.

12.
Sci Total Environ ; 697: 134210, 2019 Dec 20.
Article de Anglais | MEDLINE | ID: mdl-32380631

RÉSUMÉ

Freshwater harmful algal blooms produce a broad array of bioactive compounds, with variable polarity. Acute exposure to cyanotoxins can impact the liver, nervous system, gastrointestinal tract, skin, and immune function. Increasing evidence suggests chronic effects from low-level exposures of cyanotoxins and other associated bioactive metabolites of cyanobacterial origin. These sundry compounds persist in drinking and recreational waters and challenge resource managers in detection and removal. A systematic approach to assess the developmental toxicity of cyanobacterial metabolite standards was employed utilizing a robust and high throughput developmental Danio rerio embryo platform that incorporated a neurobehavioral endpoint, photomotor response. Subsequently, we applied the platform to cyanobacterial bloom surface water samples taken from temperate recreational beaches and tropical lake subsistence drinking water sources as a model approach. Dechorionated Danio rerio embryos were statically immersed beginning at four to six hours post fertilization at environmentally relevant concentrations, and then assessed at 24 h and 5 days for morbidity, morphological changes, and photomotor response. At least one assessed endpoint deviated significantly for exposed embryos for 22 out of 25 metabolites examined. Notably, the alkaloid lyngbyatoxin-a resulted in profound, dose-dependent morbidity and mortality beginning at 5 µg/L. In addition, hydrophobic components of extracts from beach monitoring resulted in potent morbidity and mortality despite only trace cyanotoxins detected. The hydrophilic extracts with several order of magnitude higher concentrations of microcystins resulted in no morbidity or mortality. Developmental photomotor response was consistently altered in environmental bloom samples, independent of the presence or concentration of toxins detected in extracts. While limited with respect to more polar compounds, this novel screening approach complements specific fingerprinting of acutely toxic metabolites with robust assessment of developmental toxicity, critical for chronic exposure scenarios.


Sujet(s)
Toxines bactériennes/toxicité , Cyanobactéries , Prolifération d'algues nuisibles , Microcystines/toxicité , Danio zébré , Animaux , Plage pour la baignade , Embryon non mammalien/physiopathologie , Lacs , Appréciation des risques , Uruguay
13.
FAVE, Secc. Cienc. vet. (En línea) ; 17(2): 45-49, dic. 2018. tab
Article de Espagnol | LILACS-Express | LILACS | ID: biblio-1090368

RÉSUMÉ

La intervención de los seres humanos en los procesos de cría y recría en animales de producción pueden tener diferente impacto en virtud al tipo, momento y duración de la misma. El objetivo del trabajo fue evaluar si existen cambios en parámetros fisiológicos, sanguíneos y de comportamiento en cabritos Saanen en función al tipo de crianza, 10 criados con sus madres (CT) vs. 10 criados artificialmente (CA), en las etapas de lactante y recría. Semanalmente se midió: frecuencia cardiaca (FC), temperatura rectal (TR), frecuencia respiratoria (FR), predisposición a ser atrapado y actitud de patear. Previo se tomaron 10 ml de sangre para realización del leucograma. El diseño experimental fue el de mediciones repetidas en el tiempo. Los datos fueron analizados a través del programa InfoStat. Ni entre periodos ni entre tratamientos se detectaron diferencias significativas para FC como TR. En ambos periodos a los animales del CT resultó más difícil atraparlos (lactante: p<0,0001, recría: p<0,0020). En la etapa de lactantes la cantidad de animales que pateaban fue superior (p<0,05) en CT, mientras que en recría no existieron diferencias. Durante la etapa de lactantes los conteos de neutrófilos del grupo CT fueron mayores (p<0,0001) y los de linfocitos menores (p<0,0001). Durante recría se hallaron diferencias (p<0,0001) entre grupos y la relación neutrófilos/linfocitos fue superior (p<0,0001) en un 50% en los CT. En función a lo obtenido es posible concluir que si bien existe un grado de estrés cuando el animal no habituado al ser humano se enfrenta a éste en manejos que ameriten su captura, el contacto en etapas tempranas permite aumentar el nivel de docilidad a la vez facilita la ejecución de tareas rutinarias.


Human intervention in breeding and rearing processes may have different impact in animals related to the type, moment and duration. The aim of the study was to evaluate if there are changes in physiological, blood and behavioral parameters in Saanen kids according to type of type of breeding, 10 raised with their mothers (CT) vs. 10 artificially reared (CA), in pre-weaning and post-weaning stages. Heart rate (HR), rectal temperature (TR), respiratory frequency (FR), predisposition to be caught and kicking attitude were measure once a week. Prevously, 10 ml of blood was collected for leukogram determination. Experimental design was repeated measurements in CRD. Data were analyzed by InfoStat program. Neither between periods nor between treatments were significant differences detected for HR as TR. CT animals were more difficult to catch in both periods (pre-weaning: p <0.0001, post-weaning: p <0.0020). In pre-weaning stage the number of animals that kicked was higher (p <0.05) in CT, whereas during rearing period there were no differences. During pre-weaning, neutrophil counts of the CT group were higher (p <0.0001) and lymphocytes lower (p <0.0001) than in rearing stage. During rearing differences were found (p <0.0001) between groups and the neutrophil / lymphocyte ratio was higher (p <0.0001) by 50% in the TC. It is possible to conclude that although animals can become stressed when caught; contact with humans in early stages allows increasing the level of docility and, at the same time, facility the execution of routine tasks.

14.
Arch Oral Biol ; 80: 164-174, 2017 Aug.
Article de Anglais | MEDLINE | ID: mdl-28433620

RÉSUMÉ

OBJECTIVE: The present study evaluated the nociceptive response induced by dentin hypersensitivity after dental erosion in rats that were exhibited to unpredictable chronic mild stress (UCMS)-induced depressive-like behavior. DESIGN: Adult male rats were subjected to UCMS (depression [D] group) or not (no depression [ND] group) for 30days and received either acidic solution to induce dental erosion (E) or water (W), thus forming the WND, END, WD, and ED groups. After the end of treatment, depressive-like parameters (i.e., sucrose preference and immobility in the forced swim test) and dentin hypersensitivity were evaluated. Plasma tumor necrosis factor α (TNF-α) and corticosterone levels were measured, and astrocytic glial fibrillary acidic protein (GFAP) expression was evaluated in the prefrontal cortex, hippocampus, amygdala, and hypothalamus. RESULTS: Administration of the acidic solution potentiated dentin hypersensitivity and increased corticosterone levels in the ED group compared with the WD group. TNF-α levels only increased in the WD group. The ED group exhibited an increase in astrocytic GFAP expression in the hypothalamus and prefrontal cortex but decreases in the hippocampus. CONCLUSIONS: These results suggest that UCMS exacerbated the nociceptive response associated with dentin hypersensitivity, concomitant with an increase in plasma corticosterone levels. Hypothalamic and prefrontal cortex astrogliosis in the ED group may be attributable to the increase in corticosterone associated to UCMS procedure. The reduction of astrocytic GFAP expression in the hippocampus in the ED group supports the association between dentin hypersensitivity and depression.


Sujet(s)
Hypersensibilité dentinaire/étiologie , Dépression/complications , Stress physiologique , Animaux , Corticostérone/sang , Dépression/métabolisme , Modèles animaux de maladie humaine , Protéine gliofibrillaire acide/métabolisme , Techniques immunoenzymatiques , Mâle , Microscopie électronique à balayage , Rats , Rat Wistar , Propriétés de surface , Facteur de nécrose tumorale alpha/sang
15.
Toxicon ; 129: 44-51, 2017 Apr.
Article de Anglais | MEDLINE | ID: mdl-28202362

RÉSUMÉ

The cyanobacterium Cylindrospermopsis raciborskii is an invasive species in water supply reservoirs worldwide, which can produces cylindrospermopsins and saxitoxins. In the wild, guppy (Poecilia vivipara) can be exposed to cyanotoxins, but those born and reared in laboratory are free of this contact. The aim of this paper was to comparatively measure the locomotor activity of 'wild' and 'lab' P. vivipara before and after exposure to crude extracts of two different cultures of C. raciborskii (CYRF-01), a saxitoxin-procucer strain. The movement of each fish was recorded using an image monitoring system (Videomex V®) before and after 48 h exposure to cyanobacterial extracts. Each experiment was performed during 4 h, with 1 h acclimation and 3 h recording period of the parameters Distance performed (DP), Swimming time (SwT), Stereotypic time (StT), Resting time (RT) and Average speed (AS). The quantification of saxitoxin in the solutions was performed by the enzyme-linked immunosorbent assay (ELISA). The weight or the total length did not influence the locomotor activity of fish in any of the experiments. The saxitoxin value was similar for both cultures (Culture 1: 7.3 µg L-1 and Culture 2: 8.6 µg L-1). However, in experiments with Culture 1 an increased activity in most parameters was observed, while in Culture 2, a decreased activity was observed only in 'lab' fish. Wild fish was less affected, showing higher resistance to both cyanobacterial crude extracts. This study showed that different cultures of the same strain of C. raciborskii and with similar contents of saxitoxin are able to change the locomotor activity of P. vivipara, contributing to the validation of the use of behavioral parameters to the evaluation of sublethal effects of toxic cyanobacteria on fish.


Sujet(s)
Comportement animal/effets des médicaments et des substances chimiques , Cylindrospermopsis/composition chimique , Poecilia , Saxitoxine/toxicité , Natation , Alcaloïdes , Animaux , Toxines bactériennes/toxicité , Toxines de cyanobactéries , Test ELISA , Uracile/analogues et dérivés , Uracile/toxicité
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