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RESUMEN Analizamos el uso de microhábitat para las diferentes clases etarias entre épocas climáticas y comparamos la diversidad de presas consumidas por los machos y hembras adultas de Craugastor berkenbuschii en un arroyo tropical del sureste de México. Los datos fueron colectados en diez transectos de 100 x 15 m, separados entre sí por 25 m de distancia entre ellos. Los muestreos diurnos y nocturnos se realizaron mensualmente entre septiembre 2017 y agosto 2018. A cada individuo observado le registramos el sexo, la clase etaria y el microhábitat utilizado al momento del avistamiento. Las presas consumidas fueron extraídas mediante lavados estomacales in situ. Registramos un total de 437 individuos; 165 fueron adultos, 162 juveniles y 110 crías. Los microhábitats utilizados fueron roca, hojarasca, suelo, tronco, rama, hojas y raíz, de los cuales roca fue el más utilizado independientemente de la época del año y clases etarias. Se identificaron 21 órdenes de presas, 19 órdenes en hembras y 11 en machos. El índice de diversidad verdadera (1D), mostró valores similares para machos y hembras, con 9,67 y 9,08 respectivamente. El índice de distintividad taxonómica promedio (A+) determinó que las hembras consumen una mayor diversidad de presas que los machos, con 5,12 y 4,25, respectivamente. Los resultados muestran que las diferentes clases etarias de C. berkenbuschii aprovechan una gran variedad de microhábitats entre épocas climáticas y que existen diferencias entre las presas consumidas entre machos y hembras adultas.

ABSTRACT We analyzed microhabitat use for different age classes between climatic seasons and compared the diversity of prey consumed by adult males and females of Craugastor berkenbuschii in a tropical stream in southeastern Mexico. The data was collected in ten transects of 100 x 15 m, separated from each other by 25 m of the distance between them. Day and night sampling was carried out monthly between September 2017 and august 2018. For each observed individual, we recorded the sex, age class, and microhabitat used at the time of the sighting. The consumed prey was extracted by means of in situ stomach washings. We registered a total of 437 individuals; 165 were adults, 162 were juveniles, and 110 were young. The microhabitats used were rock, litter, soil, trunk, branch, leaves, and root, of which rock was the most used regardless of the time of year and age classes. Twenty-one orders of prey were identified, 19 orders in females and 11 in males. The true diversity index (1D) showed similar values for males and females, with 9.67 and 9.08 respectively. The average taxonomic distinctness index (A+) determined that females consume a greater diversity of prey than males, with 5.12 and 4.25, respectively. The results show that the different age classes of C. berkenbuschii take advantage of a wide variety of microhabitats between climatic seasons and that there are differences between the prey consumed between adult males and females.

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Given the importance of understanding the disorders caused by trans fatty acids (TFAs), this study sought to add different concentrations hydrogenated vegetable fat (HVF) to the diet of Drosophila melanogaster during the developmental period and evaluate the effects on neurobehavioral parameters. Longevity, hatching rate, and behavioral functions were assessed, such as negative geotaxis, forced swimming, light/dark, mating, and aggressiveness. The fatty acids (FAs) present in the heads of the flies were quantified as well as serotonin (5HT) and dopamine (DA) levels. Our findings showed that flies that received HVF at all concentrations during development showed reduced longevity and hatching rates, in addition to increased depression-like, anxious-like, anhedonia-like, and aggressive behaviors. As for the biochemical parameters, there was a more significant presence of TFA in flies exposed to HVF at all concentrations evaluated and lower 5HT and DA levels. This study shows that HVF during the developmental phase can cause neurological changes and consequently induce behavioral disorders, thereby highlighting the importance of the type of FA offered in the early stages of life.

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This study aimed to evaluate the effects of the addition of saturated fat and hydrogenated vegetable fat (HVF) to the diet on depressive and anxiety-like behaviors in Drosophila melanogaster. Flies were exposed to experimental diets: regular diet (RD), or HVF in the concentrations of the substitute (SHVF), HVF 10% and HVF 20%, or Lard (L) in the concentrations of the substitute (SL), L 10% and L 20%, during seven days. Our results showed that flies fed with the HVF diet presented similar behaviors to depression, anxiety, and a higher number of aggressive events. Flies exposed to L showed only depressive-like behavior. Regarding serotonin levels (5HT), there was a significant reduction in the flies exposed to SHVF, HVF 10%, HVF 20%, and L 20%. Regarding the levels of octopamine (OA), there was a significant reduction in the flies exposed to both HVF and L rich diets when compared with the RD group. Also, there was a significant negative correlation between 5HT or OA levels and behaviors of aggressiveness, negative geotaxis, immobility time, light/dark, and grooming in the flies. This study shows that D. melanogaster can serve as a valuable model for understanding psychiatric disorders and that the type of fatty acid (FA) offered in the diet can influence these disorders. This demonstrates the importance of the composition of the FAs in the neural pathways, being able to influence the signaling of neurotransmitters, such as 5HT and OA, and thus, cause behavioral changes.

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Resumen La composición de la dieta en anfibios puede ser influenciada por diversos factores que causan su variación intraespecífica, como pueden ser la distribución geográfica, ontogenia, estacionalidad, y el sexo de los organismos. El objetivo de este estudio fue analizar la composición de la dieta en adultos de la Craugastor rhodopis (rana hojarasquera común) en la región montañosa del centro de Veracruz, México. Un total de 77 individuos adultos fueron colectados durante la época de lluvias de 2012, de los cuales 66 tuvieron contenido estomacal. Se realizó un análisis de la variación intersexual en la diversidad de la dieta, y el volumen, número de presas, y número de categorías de presa consumidas. La dieta de C. rhodopis estuvo compuesta por 20 categorías, de las cuales predominó Orthoptera en cuanto a número, volumen, frecuencia de ocurrencia e importancia relativa. Los machos consumieron presas de menor tamaño en relación a las hembras. Aunque ambos sexos consumieron similar número de presas, se encontró un efecto significativo de la interacción del sexo y el tamaño de las ranas sobre esta variable de la dieta, en la cual las hembras pequeñas consumen más presas que las grandes, y los machos grandes consumen más presas que los pequeños. El alto consumo de ortópteros (al menos en cuanto a volumen) es un fenómeno común dentro de la familia Craugastoridae y posiblemente está relacionado con el éxito de algunas especies en los ecosistemas donde habitan. A pesar de que la composición de la dieta fue similar entre sexos en C. rhodopis, se sugiere que la competencia intersexual por los recursos tróficos es mínima, dadas las diferencias en el tamaño de presas consumidas por machos y hembras.(AU)

Abstract Dietary composition in amphibians may be influenced by several factors that cause their intraspecific variation, such as geographic distribution, ontogeny, seasonality, and sex of organisms. The objective of this study was to analyze the composition of the diet in adults of the Polymorphic Robber Frog Craugastor rhodopis in the mountainous region of central Veracruz, Mexico. A total of 77 adult individuals were collected during the rainy season of 2012, of which 66 had stomach contents. We performed an analysis of the intersexual variation in diet diversity, volume, number of prey, and number of prey categories consumed. The diet of C. rhodopis was composed by 20 categories. Orthoptera predominated in terms of number, volume, frequency of occurrence, and relative importance. Males consumed smaller prey items relative to females. Although both sexes consumed similar numbers of prey, we found a significant effect of interaction of sex and size of frogs on this variable, with small females consuming more prey than the large ones, whereas in males the opposite occurred. High consumption of orthopterans (at least in volume) is a common phenomenon within Craugastoridae and is possibly related to the success of some species in the ecosystems where they live. Although the composition of the diet was similar between sexes in C. rhodopis, we suggest that intersexual competition for trophic resources is minimal, given differences in prey size consumed by males and females.(AU)

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