Effect of dietary protein: lipid ratio on growth and body composition in bullfrog (Lithobates catesbeianus)

A feeding trial was performed to assess dietary protein:lipid ratios for the grow-out phase of the bullfrog (Lithobates catesbeianus). Nine balanced isoenergetic diets were formulated, combining three different protein levels (300, 400, and 500 g kg−1) with three different lipid levels (50, 100, and 200 g kg−1), designated as P300/50L, P300/100L, P300/200L, P400/50L, P400/100L, P400/200L, P500/50L, P500/100L, and P500/200L. Additionally, a commercial fish feed, commonly used in Mexico to feed bullfrogs, was also tested during the experiment. Growth performance, animal performance parameters, carcass composition, and fatty acid profiles in muscle and liver were evaluated. The feeding trial results showed that all the experimental diets enhanced growth, feed conversion ratio, and frog-leg weight compared with the commercial diet. Bullfrogs had higher growth with 400 and 500 g kg−1 of dietary protein regardless of dietary lipid content. It was also notable that with the P500/200L diet, frogs doubled the weight of those fed the commercial diet. DHA, EPA, and total omega-3 fatty acids were double in muscle and two to eight times higher in the liver compared with the commercial diet. In all cases, the final proximal composition of carcass reflected the diet composition. It is suggested that a diet containing 400 g kg−1 of protein and 50 g kg−1 lipids (protein/lipid ratio: 7.4; gross energy: 18.2 MJ kg−1) is adequate for bullfrog performance during the grow-out phase to achieve market size in a shorter period, thus, reducing farming risks and production costs.

Diet of a bromeligenous species of treefrog in the Brazilian semiarid / Dieta de uma espécie bromelígena de anuro do semiárido brasileiro

Phyllodytes tuberculosus is a bromeligenous anuran species whose geographic distribution is restricted to areas of the Caatinga and to transition zones between Caatinga and Atlantic Forest in the central-south of the state of Bahia. Its existence in close relationship with bromeliads and its occurrence in dry and highly seasonal environments drove us to the supposition that species is opportunistic/generalist regard to diet. We collected the items present in the stomach of 43 P. tuberculosus individuals with stomach-flushing method. Of these, 18 stomach contents were obtained during the dry period (April­October), and 25 during the rainy period (November­March). We recorded nine classes of prey, finding the greatest relative importance for the categories Formicidae and Coleoptera in dry season and Blattodea (Termites), Formicidae and Coleoptera in the rainy season. Phyllodytes tuberculosus presented a varied, possibly opportunistic diet in semiarid environments. Additionally, we report an apparent temporal differentiation related to the typical Caatinga seasonality. This study adds to the data on the natural history of an anuran species adapted to a semiarid environment with a narrow geographic distribution.

Phyllodytes tuberculosus é uma espécie de anuro bromelígena cuja distribuição geográfica está restrita a áreas de Caatinga e zonas de transição entre Caatinga e Mata Atlântica no centro-sul do estado da Bahia. Sua relação próxima com bromélias e sua ocorrência em ambientes secos e fortemente sazonais nos levou a supor que a espécie apresenta uma dieta generalista/oportunista. Por meio de lavagem estomacal, coletamos os itens alimentares presentes no estômago de 43 indivíduos de P. tuberculosus. Destes, 18 estômagos foram obtidos durante a estação seca (Abril-Outubro) e 25 durante a estação chuvosa (Novembro­Março). Nós registramos nove classes de presas, sendo que as maiores importâncias relativas foram observadas para os itens Formicidae e Coleoptera na estação seca e Blattodea (Termites), Formicidae e Coleoptera no conteúdo recuperado na estação chuvosa. Phyllodytes tuberculosus apresentou uma dieta variada, possivelmente oportunista, condizente com a vida em ambientes semiáridos. Ademais, também observamos uma aparente diferenciação temporal relacionada a sazonalidade típica da Caatinga. Este estudo adiciona dados a respeito da história natural de uma espécie de anuro adaptada a ambientes semiáridos e com distribuição geográfica restrita.

Diet of a bromeligenous species of treefrog in the Brazilian semiarid / Dieta de uma espécie bromelígena de anuro do semiárido brasileiro

Phyllodytes tuberculosus is a bromeligenous anuran species whose geographic distribution is restricted to areas of the Caatinga and to transition zones between Caatinga and Atlantic Forest in the central-south of the state of Bahia. Its existence in close relationship with bromeliads and its occurrence in dry and highly seasonal environments drove us to the supposition that species is opportunistic/generalist regard to diet. We collected the items present in the stomach of 43 P. tuberculosus individuals with stomach-flushing method. Of these, 18 stomach contents were obtained during the dry period (AprilOctober), and 25 during the rainy period (NovemberMarch). We recorded nine classes of prey, finding the greatest relative importance for the categories Formicidae and Coleoptera in dry season and Blattodea (Termites), Formicidae and Coleoptera in the rainy season. Phyllodytes tuberculosus presented a varied, possibly opportunistic diet in semiarid environments. Additionally, we report an apparent temporal differentiation related to the typical Caatinga seasonality. This study adds to the data on the natural history of an anuran species adapted to a semiarid environment with a narrow geographic distribution.(AU)

Phyllodytes tuberculosus é uma espécie de anuro bromelígena cuja distribuição geográfica está restrita a áreas de Caatinga e zonas de transição entre Caatinga e Mata Atlântica no centro-sul do estado da Bahia. Sua relação próxima com bromélias e sua ocorrência em ambientes secos e fortemente sazonais nos levou a supor que a espécie apresenta uma dieta generalista/oportunista. Por meio de lavagem estomacal, coletamos os itens alimentares presentes no estômago de 43 indivíduos de P. tuberculosus. Destes, 18 estômagos foram obtidos durante a estação seca (Abril-Outubro) e 25 durante a estação chuvosa (NovembroMarço). Nós registramos nove classes de presas, sendo que as maiores importâncias relativas foram observadas para os itens Formicidae e Coleoptera na estação seca e Blattodea (Termites), Formicidae e Coleoptera no conteúdo recuperado na estação chuvosa. Phyllodytes tuberculosus apresentou uma dieta variada, possivelmente oportunista, condizente com a vida em ambientes semiáridos. Ademais, também observamos uma aparente diferenciação temporal relacionada a sazonalidade típica da Caatinga. Este estudo adiciona dados a respeito da história natural de uma espécie de anuro adaptada a ambientes semiáridos e com distribuição geográfica restrita.(AU)

Diet of bromeliad-frog Phyllodytes luteolus (Anura, Hylidae) in Atlantic Forest environments: what have the frogs been eating outside sandy coastal plains?

Knowledge about the diet of anurans in different environments is essential to understanding important aspects of their trophic ecology. The bromeliad-frog Phyllodytes luteolus inhabits tank bromeliads in sandy coastal plains and lowland forests on the mainland, as well as a continental island in southeastern Brazil. In this work, we describe and analyze the diet of P. luteolus in three environments. We obtained the consumed prey items of 92 frogs (32 from sandy coastal plain, 32 from lowland forest and 28 from the island) via a stomach-flushing procedure. We found some variations in consumed prey composition and prey volume across populations, but ants represented the most important consumed prey in all environments. Only ants had a relative importance greater than 50%, which may suggest a specialized diet that transcends the sandy coastal plain environment.

Diet of bromeliad-frog Phyllodytes luteolus (Anura, Hylidae) in Atlantic Forest environments: what have the frogs been eating outside sandy coastal plains?

Knowledge about the diet of anurans in different environments is essential to understanding important aspects of their trophic ecology. The bromeliad-frog Phyllodytes luteolus inhabits tank bromeliads in sandy coastal plains and lowland forests on the mainland, as well as a continental island in southeastern Brazil. In this work, we describe and analyze the diet of P. luteolus in three environments. We obtained the consumed prey items of 92 frogs (32 from sandy coastal plain, 32 from lowland forest and 28 from the island) via a stomach-flushing procedure. We found some variations in consumed prey composition and prey volume across populations, but ants represented the most important consumed prey in all environments. Only ants had a relative importance greater than 50%, which may suggest a specialized diet that transcends the sandy coastal plain environment.(AU)

Reproductive and feeding biology of the common lancehead Bothrops atrox (Serpentes, Viperidae) from central and southwestern Brazilian Amazonia / Biologia reprodutiva e alimentar da jararaca Bothrops atrox (Serpentes, Viperidae) do centro e sudoeste da Amazônia brasileira

The pitviper Bothrops atrox is a widely distributed and medically important snake in Amazonia. Given that the reproductive and feeding biology of snakes varies geographically, we aimed to characterize the natural history of individuals from the central and southwestern portions of the biome. We analyzed museum-preserved specimens collected in the region between the metropolitan areas of the Brazilian cities of Manaus and Porto Velho. We took morphometric measurements and performed the analysis of gonads and digestive tracts of 109 individuals. Females attain sexual maturity with larger body sizes. Adults of the species show pronounced sexual dimorphism in body size, with females being larger. The reproductive cycle, especially in males, appears to be synchronized with regional rainfall, which markedly differed across the biome. The pitvipers had a generalist diet, consuming a wide range of prey such as centipedes, frogs, lizards, snakes and mammals. We provide the first record of predation of the snake Imantodes cenchoa (Dipsadidae) by B. atrox. There was an ontogenetic shift in the diet: smaller individuals fed mainly on ectothermic prey (centipedes, frogs, lizards and snakes), while adults tended to incorporate endothermic prey (mammals) to their food repertoire.(AU)

A jararaca Bothrops atrox é uma serpente de ampla distribuição e de importância médica na Amazônia. Visto que a biologia reprodutiva e alimentar de serpentes varia geograficamente, nosso objetivo foi o de caracterizar a história natural de indivíduos provenientes das porções central e sudoeste do bioma no Brasil. Analisamos espécimes preservados coletados na área compreendida entre as regiões metropolitanas dos municípios brasileiros de Manaus e Porto Velho. Realizamos medidas morfométricas e analisamos as gônadas e o trato digestivo de 109 exemplares. Fêmeas apresentaram maturação sexual com tamanhos corporais maiores que os machos. Adultos apresentaram marcado dimorfismo sexual em tamanho, sendo que as fêmeas foram, em média, maiores que os machos. O ciclo reprodutivo, especialmente em machos, pareceu estar sincronizado com o regime regional de chuvas, que difere de outras partes do bioma. As serpentes apresentaram dieta generalista, tendo ingerido uma ampla gama de presas, como lacraias, anuros, lagartos, serpentes e mamíferos. Registramos, pela primeira vez, a predação da serpente Imantodes cenchoa (Dipsadidae) por B. atrox. Houve mudança ontogenética na dieta: indivíduos menores se alimentaram principalmente de presas ectotérmicas (lacraias, anuros, lagartos e serpentes) e adultos tenderam a incorporar itens endotérmicos (mamíferos) ao repertório alimentar.(AU)

Frog meat in special diets: potential for use as a functional food / Carne de rã em dietas especiais: potencial de utilização como alimento funcional

Frog meat is a highly digestible food, which justifies its use in special diets. The aim of this study was to evaluate the potential for use of frog meat in hospital diets and in diets recommended by physicians, in addition to promoting its consumption. Interviews were performed at hospitals and medical offices in Rio de Janeiro (RJ, Brazil). The survey identified that 72% of interviewed - physicians, nutritionists, and staff responsible for hospital kitchens - do not know the nutritional properties of frog meat, and 50% believe there are difficulties in its use and highlighted the little availability of the product in the market and its high price. Frog meat is considered a healthy food,but the importance of its use and forms of preparation must be divulged.(AU)

A carne de rã apresenta alta digestibilidade evidenciando a importância da utilização em dietas especiais. O objetivo do estudo foi avaliar o potencial da utilização da carne de rã nas dietas hospitalares e em dietas recomendadas pelos médicos e ainda promover o consumo. Foram realizadas entrevistas em hospitais e consultórios da cidade do Rio de Janeiro (RJ, Brasil). Apesquisa identificou que 72% dos entrevistados - médicos, nutricionistas e responsáveis por cozinhas hospitalares - não conhecem as características nutricionais da carne, e 50% acredita que hádificuldades na sua utilização e destacou a falta de disponibilidade no mercado e o preço elevado do produto. A carne de rã é considerada um alimento saudável, mas a importância da utilização e as formas de preparo precisam ser divulgadas.(AU)

Frog meat in special diets: potential for use as a functional food / Carne de rã em dietas especiais: potencial de utilização como alimento funcional

Frog meat is a highly digestible food, which justifies its use in special diets. The aim of this study was to evaluate the potential for use of frog meat in hospital diets and in diets recommended by physicians, in addition to promoting its consumption. Interviews were performed at hospitals and medical offices in Rio de Janeiro (RJ, Brazil). The survey identified that 72% of interviewed - physicians, nutritionists, and staff responsible for hospital kitchens - do not know the nutritional properties of frog meat, and 50% believe there are difficulties in its use and highlighted the little availability of the product in the market and its high price. Frog meat is considered a healthy food,but the importance of its use and forms of preparation must be divulged.

A carne de rã apresenta alta digestibilidade evidenciando a importância da utilização em dietas especiais. O objetivo do estudo foi avaliar o potencial da utilização da carne de rã nas dietas hospitalares e em dietas recomendadas pelos médicos e ainda promover o consumo. Foram realizadas entrevistas em hospitais e consultórios da cidade do Rio de Janeiro (RJ, Brasil). Apesquisa identificou que 72% dos entrevistados - médicos, nutricionistas e responsáveis por cozinhas hospitalares - não conhecem as características nutricionais da carne, e 50% acredita que hádificuldades na sua utilização e destacou a falta de disponibilidade no mercado e o preço elevado do produto. A carne de rã é considerada um alimento saudável, mas a importância da utilização e as formas de preparo precisam ser divulgadas.

Diet of Dendropsophus microcephalus and Scarthyla vigilans (Anura: Hylidae) at a locality in north-western Venezuela with notes on microhabitat occupation

The coexistence of species with similar ecological requirements (food, space, time) has typically drawn attention of researchers because competition for resources is expected to be high. The diet and microhabitat occupation of two morphologically and ecologically similar species of Hylidae (Anura), Dendropsophus microcephalus and Scarthyla vigilans, were analyzed at a locality in north-western Venezuela, with the aim of addressing the potential for space and food competition between them. Diet was estimated through the analysis of stomach contents and microhabitat occupation was estimated through recordings of perch type, height and horizontal distance to water. Thirty-six prey categories (32 families, 4 orders) of arthropods were identified: 30 categories in D. microcephalus and 21 categories in S. vigilans. The most important prey (RII) in D. microcephalus were Agelenidae (11.1%), Tachinidae (9.32%) and Lepidoptera-larvae (7.96%). Gryllidae (14.13%), Cicadidae (9.1%), Cicadellidae (8.3%) and Delphacidae (8.02%) were the most important in S. vigilans. Diet overlap was relatively low (0.32). Both species have relatively generalist diets. Both species occupied the same type of perches (leaves and stems of Dicotyledons and Monocotyledons) and heights (average: S. vigilans, 24 ± 16.2 cm; D. microcephalus, 22.7 ± 9.5 cm). The potential for space competition is high if perches are limited and food competition is expected to be low.

La coexistencia de especies con requerimientos ecológicos similares (alimento, espacio, tiempo) típicamente ha atraído a los investigadores porque se espera que la competencia por recursos sea alta. La dieta y la ocupación de microhábitat de dos especies morfológica y ecológicamente similares de Hylidae (Anura) se analizaron en una localidad al noroeste de Venezuela, con el objetivo de evaluar el potencial para competencia entre ellas. La dieta se estimó a través del análisis de los contenidos estomacales y la ocupación del microhábitat por medio de registros del tipo y altura de la percha y la distancia horizontal al agua. Se identificaron 36 categorías de presa (32 familias, 4 órdenes); 30 en D. microcephalus y 21 en S. vigilans. Las presas más importantes (RII) en D. microcephalus fueron Agelenidae (11,1%), Tachinidae (9,32%) y Lepidoptera-larva (7,96%). Gryllidae (14,13%), Cicadidae (9,1%), Cicadellidae (8,3%) and Delphacidae (8,02%) fueron las más importantes en S. vigilans. Ambas especies tienen dietas relativamente generalistas. La superposición de las dietas fue relativamente baja (0,32). Ambas especies ocuparon el mismo tipo de perchas (hojas y tallos de dicotiledóneas y monocotiledóneas) a las mismas alturas. El potencial para la competencia por espacio es alto si las perchas fuesen escasas, pero se espera que la competencia por el alimento sea baja.

Diet of Dendropsophus microcephalus and Scarthyla vigilans (Anura: Hylidae) at a locality in north-western Venezuela with notes on microhabitat occupation

The coexistence of species with similar ecological requirements (food, space, time) has typically drawn attention of researchers because competition for resources is expected to be high. The diet and microhabitat occupation of two morphologically and ecologically similar species of Hylidae (Anura), Dendropsophus microcephalus and Scarthyla vigilans, were analyzed at a locality in north-western Venezuela, with the aim of addressing the potential for space and food competition between them. Diet was estimated through the analysis of stomach contents and microhabitat occupation was estimated through recordings of perch type, height and horizontal distance to water. Thirty-six prey categories (32 families, 4 orders) of arthropods were identified: 30 categories in D. microcephalus and 21 categories in S. vigilans. The most important prey (RII) in D. microcephalus were Agelenidae (11.1%), Tachinidae (9.32%) and Lepidoptera-larvae (7.96%). Gryllidae (14.13%), Cicadidae (9.1%), Cicadellidae (8.3%) and Delphacidae (8.02%) were the most important in S. vigilans. Diet overlap was relatively low (0.32). Both species have relatively generalist diets. Both species occupied the same type of perches (leaves and stems of Dicotyledons and Monocotyledons) and heights (average: S. vigilans, 24 ± 16.2 cm; D. microcephalus, 22.7 ± 9.5 cm). The potential for space competition is high if perches are limited and food competition is expected to be low.(AU)

La coexistencia de especies con requerimientos ecológicos similares (alimento, espacio, tiempo) típicamente ha atraído a los investigadores porque se espera que la competencia por recursos sea alta. La dieta y la ocupación de microhábitat de dos especies morfológica y ecológicamente similares de Hylidae (Anura) se analizaron en una localidad al noroeste de Venezuela, con el objetivo de evaluar el potencial para competencia entre ellas. La dieta se estimó a través del análisis de los contenidos estomacales y la ocupación del microhábitat por medio de registros del tipo y altura de la percha y la distancia horizontal al agua. Se identificaron 36 categorías de presa (32 familias, 4 órdenes); 30 en D. microcephalus y 21 en S. vigilans. Las presas más importantes (RII) en D. microcephalus fueron Agelenidae (11,1%), Tachinidae (9,32%) y Lepidoptera-larva (7,96%). Gryllidae (14,13%), Cicadidae (9,1%), Cicadellidae (8,3%) and Delphacidae (8,02%) fueron las más importantes en S. vigilans. Ambas especies tienen dietas relativamente generalistas. La superposición de las dietas fue relativamente baja (0,32). Ambas especies ocuparon el mismo tipo de perchas (hojas y tallos de dicotiledóneas y monocotiledóneas) a las mismas alturas. El potencial para la competencia por espacio es alto si las perchas fuesen escasas, pero se espera que la competencia por el alimento sea baja.(AU)

Living in a same microhabitat should means eating the same food? Diet and trophic niche of sympatric leaf-litter frogs Ischnocnema henselii and Adenomera marmorata in a forest of Southern Brazil / Viver no mesmo ambiente significa comer o mesmo alimento? Dieta e nicho trófico dos anuros simpátricos de folhiço Ischnocnema henselii e Adenomera marmorata em uma floresta do sul do Brasil

In this study we analyzed diet composition, niche breadth and overlap of the two leaf-litter frogs Ischnocnema henselii and Adenomera marmorata. Frogs were collected in an Atlantic Rainforest area in the Reserva Natural Salto Morato, in Paraná State, Southern Brazil, using plots of 16 m2 established on forest floor. Ischnocnema henselii consumed 18 different types of prey and the diet of this species was composed predominantly by Hymenoptera (Formicidae) (15.4%), Araneae (13.83%), Orthoptera (6.15%) and Opiliones (6.15%), whereas Adenomera marmorata consumed 15 different types of prey and its diet was composed mainly by Hymenoptera (Formicidae) (45.7%), Acari (31.8%) and Blattodea (14.8%). The niche breadth of I. henselii was BA = 0.43 and that of A. marmorata was BA = 0.19. The diet of the two sympatric species of leaf-litter frogs was basically composed by arthropods and the trophic niche overlap among them did not differ from expected at random. The differences in prey consumption should potentially facilitate the coexistence of two sympatric frogs on the forest floor. Possibly, this difference of prey consumption partly reflects differences in jaw width, species-specific body size of the two species and the period of activity of these two species.(AU)

Neste estudo analisamos a composição da dieta e a amplitude e sobreposição do nicho trófico dos anuros de folhiço Ischnocnema henselii e Adenomera marmorata. Os anuros foram coletados em uma área de Mata Atlântica na Reserva Natural Salto Morato, no Estado do Paraná, Sul do Brasil, utilizando o método de parcelas de 16 m2 estabelecidas no chão da floresta. Ischnocnema henselii consumiu 18 diferentes tipos de presa e a dieta desta espécie foi composta predominantemente por Hymenoptera (Formicidae) (15,4%), Araneae (13,83%), Orthoptera (6,15%) e Opiliones (6,15%), enquanto Adenomera marmorata consumiu 15 diferentes tipos de presas e sua dieta foi composta principalmente por Hymenoptera (Formicidae) (45,7%), Acari (31,8%) e Blattodea (14,8%). A amplitude de nicho de I. henselii foi BA = 0,43 e de A.marmorata foi BA = 0,19. A dieta das duas espécies de anuros simpátricos do folhiço por nós estudadas foi composta basicamente de artrópodes e a sobreposição de nicho trófico entre elas não diferiu do esperado para ocorrer ao acaso. As diferenças no consumo de presas potencialmente devem facilitar a coexistência desses dois anuros simpátricos no chão da floresta. Possivelmente, esta diferença no consumo de presas em parte reflete diferenças na largura da mandíbula, no tamanho do corpo e no período de atividade dessas duas espécies.(AU)

Phyllomedusa ecuatoriana Cannatella (Amphibia: Hylidae): variación, descripción del renacuajo, vocalización y anotaciones sobre la historia natural

Information is presented on morphological variation in the frog, Phyllomedusa ecuatoriana, with a description ot the tadpole, vocalizations, and notes on its natural history and distribu‑ tion, based on material recently collected in the Cordillera del Cóndor, Zamora Chinchipe Province, Ecuador. Phyllomedusa ecuatoriana is of médium size (male SVL length 46.1 to 55.4 mm; female SVL 72.2 mm). The tapole (Gosner stage 26) has a dentary formula of 2 (2)/3 (1); tooth row P3 is smaller than P1 and P2. The tadpoles develop in pools of various sizes in turbid water stained by the presence of tanins. The vocalizations are modulated fre‑ quencies, with the dominant frequency averaging 1.53 kHz; the calls are composed of a single note and 2‑3 pulses. Adult frogs feed primarily on spiders (20%) of the family Argiopidae

Phyllomedusa ecuatoriana Cannatella (Amphibia: Hylidae): variación, descripción del renacuajo, vocalización y anotaciones sobre la historia natural

Information is presented on morphological variation in the frog, Phyllomedusa ecuatoriana, with a description ot the tadpole, vocalizations, and notes on its natural history and distribu‑ tion, based on material recently collected in the Cordillera del Cóndor, Zamora Chinchipe Province, Ecuador. Phyllomedusa ecuatoriana is of médium size (male SVL length 46.1 to 55.4 mm; female SVL 72.2 mm). The tapole (Gosner stage 26) has a dentary formula of 2 (2)/3 (1); tooth row P3 is smaller than P1 and P2. The tadpoles develop in pools of various sizes in turbid water stained by the presence of tanins. The vocalizations are modulated fre‑ quencies, with the dominant frequency averaging 1.53 kHz; the calls are composed of a single note and 2‑3 pulses. Adult frogs feed primarily on spiders (20%) of the family Argiopidae(AU)

Daily behavioral activities of bullfrog Lithobates catesbeianus (Shaw 1802) / Atividades comportamentais diárias de rãs-touro Lithobates catesbeianus (Shaw 1802)

Studies on the daily behavioral activities of bullfrogs in laboratories may indicate avenues for appropriate technical management for this specie culture. Twenty-four post-metamorphic phase Lithobates catesbeianus (Shaw 1802) bullfrogs had their daily activities described. The animals were housed in six experimental stalls and feed was offered once a day at random times over 10 days of filming. Behavioral activity in each stall was recorded for the first 15 minutes of every hour in a 24-hour period. As results, we observed that ingestion and movement on dry ground were more common at dawn and rare in dark; inactivity on dry ground occurred more in the late night and at dawn. Consequently, there was preference for sheltering less at dawn and in the end of dark phases. The inactivity behavior in the water was more frequent during the early dark phase, showing an inverse relationship with respect to preferred times for feed ingestion. As a result of observed behaviors, we recommended that feed offerings for bullfrogs in captivity are during the light phase of day and that it is available until the following morning.(AU)

Pesquisas relativas às atividades diárias de rãs touro em laboratório podem fornecer subsídios para definir técnicas de manejo apropriadas para o cultivo desta espécie. Vinte e quarto rãs da espécie Lithobates catesbeianus (Shaw 1802) na fase pós-metamórfica tiveram suas atividades diárias descritas. Os animais foram alojados em seis baias experimentais, seis em cada, com o alimento ofertado uma vez ao dia em horários aleatórios ao longo de 10 dias de filmagem. As atividades comportamentais foram registradas em cada baia nos primeiros 15 minutos de cada hora, por um período de 24 horas. Como resultados, nós observamos que a ingestão do alimento e movimentos na área seca foram mais comuns ao amanhecer e raros na fase escura do dia; a inatividade na área seca ocorreu mais frequentemente tarde da noite e de madrugada. Consequentemente, a utilização do abrigo foi menor no amanhecer e no final da fase escura. O comportamento de inatividade na água foi mais frequente no início da fase escura, mostrando uma relação inversa com relação com o horário preferido para ingestão do alimento. Com base nos resultados obtidos, nós recomendamos que o alimento artificial seja ofertado, para rãs em cativeiro, durante a fase clara do dia e permaneça disponível até a manhã seguinte. (AU)

Daily behavioral activities of bullfrog Lithobates catesbeianus (Shaw 1802) / Atividades comportamentais diárias de rãs-touro Lithobates catesbeianus (Shaw 1802)

Studies on the daily behavioral activities of bullfrogs in laboratories may indicate avenues for appropriate technical management for this specie culture. Twenty-four post-metamorphic phase Lithobates catesbeianus (Shaw 1802) bullfrogs had their daily activities described. The animals were housed in six experimental stalls and feed was offered once a day at random times over 10 days of filming. Behavioral activity in each stall was recorded for the first 15 minutes of every hour in a 24-hour period. As results, we observed that ingestion and movement on dry ground were more common at dawn and rare in dark; inactivity on dry ground occurred more in the late night and at dawn. Consequently, there was preference for sheltering less at dawn and in the end of dark phases. The inactivity behavior in the water was more frequent during the early dark phase, showing an inverse relationship with respect to preferred times for feed ingestion. As a result of observed behaviors, we recommended that feed offerings for bullfrogs in captivity are during the light phase of day and that it is available until the following morning.

Pesquisas relativas às atividades diárias de rãs touro em laboratório podem fornecer subsídios para definir técnicas de manejo apropriadas para o cultivo desta espécie. Vinte e quarto rãs da espécie Lithobates catesbeianus (Shaw 1802) na fase pós-metamórfica tiveram suas atividades diárias descritas. Os animais foram alojados em seis baias experimentais, seis em cada, com o alimento ofertado uma vez ao dia em horários aleatórios ao longo de 10 dias de filmagem. As atividades comportamentais foram registradas em cada baia nos primeiros 15 minutos de cada hora, por um período de 24 horas. Como resultados, nós observamos que a ingestão do alimento e movimentos na área seca foram mais comuns ao amanhecer e raros na fase escura do dia; a inatividade na área seca ocorreu mais frequentemente tarde da noite e de madrugada. Consequentemente, a utilização do abrigo foi menor no amanhecer e no final da fase escura. O comportamento de inatividade na água foi mais frequente no início da fase escura, mostrando uma relação inversa com relação com o horário preferido para ingestão do alimento. Com base nos resultados obtidos, nós recomendamos que o alimento artificial seja ofertado, para rãs em cativeiro, durante a fase clara do dia e permaneça disponível até a manhã seguinte.

Trophic ecology and microhabitat utilization by the Bufo gargarizans, Rana guentheri, and Rana limnocharis in southwestern China

We studied the trophic ecology and microhabitat use of the Asiatic toad, Bufo gargarizans Cantor, 1842; Guentheri frog, Rana guentheri (Boulenger, 1882); and the Ricefield frog, Rana limnocharis (Boie, 1834). These three species are common around Nanchong City, in southwestern China, where they live in the same habitat before hibernation. The main objective of this study was to analyze the diets and patterns of coexistence relative to the microhabitat of each species. In the Asiatic toad, based on index of relative importance, the diet was dominated by adult Coleoptera, Isopoda, and Hymenoptera (29.53%, 22.07%, and 15.20%, respectively), while the Guenther's frog and Ricefield frog ingested predominantly Orthoptera (67.44% and 40.94%, respectively). The standardized feeding niche breadth of the Asiatic toad (0.277) was wider than that of the Guentheri frog (0.177) and Ricefield frog (0.269). The overlap in the trophic niche (prey proportion) between the toad and two species of frog was low (toad vs. Guentheri frog, C H = 0.526; toad vs. Ricefield frog, C H = 0.521), while this was high for the two species of frogs (C H = 0.942). The three species also differed in microhabitat use. Asiatic toads showed strong preference for small roads close to shrubs or pre-harvest corn, while Guenther's frogs preferred bare surfaces on habitat edges, and Ricefield frogs showed a preference for bare surfaces as feeding sites in the middle of habitat. The difference in diet observed during three species seems to be explained by the difference in microhabitat use and body size of three species.

Trophic ecology and microhabitat utilization by the Bufo gargarizans, Rana guentheri, and Rana limnocharis in southwestern China

We studied the trophic ecology and microhabitat use of the Asiatic toad, Bufo gargarizans Cantor, 1842; Guentheri frog, Rana guentheri (Boulenger, 1882); and the Ricefield frog, Rana limnocharis (Boie, 1834). These three species are common around Nanchong City, in southwestern China, where they live in the same habitat before hibernation. The main objective of this study was to analyze the diets and patterns of coexistence relative to the microhabitat of each species. In the Asiatic toad, based on index of relative importance, the diet was dominated by adult Coleoptera, Isopoda, and Hymenoptera (29.53%, 22.07%, and 15.20%, respectively), while the Guenther's frog and Ricefield frog ingested predominantly Orthoptera (67.44% and 40.94%, respectively). The standardized feeding niche breadth of the Asiatic toad (0.277) was wider than that of the Guentheri frog (0.177) and Ricefield frog (0.269). The overlap in the trophic niche (prey proportion) between the toad and two species of frog was low (toad vs. Guentheri frog, C H = 0.526; toad vs. Ricefield frog, C H = 0.521), while this was high for the two species of frogs (C H = 0.942). The three species also differed in microhabitat use. Asiatic toads showed strong preference for small roads close to shrubs or pre-harvest corn, while Guenther's frogs preferred bare surfaces on habitat edges, and Ricefield frogs showed a preference for bare surfaces as feeding sites in the middle of habitat. The difference in diet observed during three species seems to be explained by the difference in microhabitat use and body size of three species.