Reproducción y limitaciones de pesca recomendadas para el caracol marino Hexaplex princeps (Neogastropoda: Muricidae) en Guerrero, México / Reproduction and recommended fishing limitations for the marine snail Hexaplex princeps (Neogastropoda: Muricidae) in Guerrero, Mexico

Abstract Introduction: The snail Hexaplex princeps is the most important gastropod in the fishery of Guerrero, but capture is not legally regulated for lack of enough studies about its reproduction, growth and other fishing aspects. Objective: To assess fishery data for H. princeps in Guerrero. Methods: From October 2016 to December 2017, we analyzed histological samples of the gonads from 6 to 13 individuals per month. We also collected data on pre-reproductive organisms captured in Costa Chica (2013 and 2014), Costa Grande (2017) and Acapulco (2019 and 2020). Results: Both sexes have five stages of gonadal development; most reproductive activity was from December to July, related to sea surface temperatures of 26 to 28 °C. The LC M in females was 94.1 mm (males: 86.1 mm). There was a high percentage of juvenile organisms in the catches (88.6 %). Conclusions: To let these snails reproduce at least once, we recommend a fishing ban from December to July, and that the minimum size of commercial capture be set at 94.1 mm.

Resumen Introducción: El caracol Hexaplex princeps es el gasterópodo más importante en la pesquería de Guerrero, pero su captura no está regulada legalmente por falta de suficientes estudios sobre su reproducción, crecimiento y otros aspectos de la pesca. Objetivo: Evaluar los datos de pesca de H. princeps en Guerrero. Métodos: De octubre 2016 a diciembre 2017, analizamos muestras histológicas de las gónadas de 6 a 13 individuos por mes. También recolectamos datos sobre organismos pre-reproductivos capturados en Costa Chica (2013 y 2014), Costa Grande (2017) y Acapulco (2019 y 2020). Resultados: Ambos sexos tienen cinco etapas de desarrollo gonadal; la mayor actividad reproductiva fue de diciembre a julio, relacionada con las temperaturas superficiales del mar, que se encuentran entre 26 y 28 °C. El LC M en hembras fue de 94.1 mm (machos: 86.1 mm). Hubo un alto porcentaje de organismos juveniles en las capturas (88.6 %). Conclusiones: Para que estos caracoles se reproduzcan al menos una vez, se recomienda una veda de diciembre a julio y que la talla mínima de captura comercial se fije en 94.1 mm.

Spatial and temporal distribution and microhabitat use of aquatic breeding amphibians (Anura) in a seasonally dry tropical forest in Chamela, Mexico / Distribución espacial y temporal y uso de microhábitat de los anuros con reproducción acuática en un bosque seco estacional en Chamela, México

Abstract: The distribution of amphibians is affected by abiotic and biotic factors, availability of resources and the characteristics of reproductive sites. In particular, reproductive activity of aquatic-breeding anurans that inhabit tropical dry areas is affected by rainfall, which determines the availability and quality of reproductive sites. In this study, we analyzed the spatial and temporal distribution of anurans with indirect development in a tropical dry forest in Western Mexico, during two rainy seasons (July 10-October 4, 2013, and June 26-September 26, 2014). We collected data on the occupancy and reproductive activity of 15 species in four temporary streams, and evaluated their relationship with precipitation, humidity and temperature. We determined richness, abundance and diversity of species in each stream; we also identified differences in the reproductive strategies and microhabitats used by the species. The most abundant species were: Tlalocohyla smithii and Exerodonta smaragdina, whereas the least abundant were Leptodactylus melanonotus and Incilius mazatlanensis. Species richness, abundance and reproductive activity peaked alongside the stream with the greatest number of breeding sites (e.g. pools). We found temporal segregation in the occupancy and reproductive activity of species in all streams which were mainly associated with precipitation. However, occupancy and reproductive activity of some species overlapped up to four weeks during part of the breeding season. Most species used specific substrates for particular reproductive activities (e.g. oviposition), but used a range of microhabitats (leaf-litter, water, rocks, branches, leaves, logs, etc.) for others (e.g. calling). We discuss these behavioral differences as factors that facilitate coexistence of species in this environment in the rainy season. Rev. Biol. Trop. 65 (3): 1082-1094. Epub 2017 September 01.

Resumen: La distribución de los anfibios se ve afectada por factores bióticos y abióticos, la disponibilidad de recursos y las características de los sitios de reproducción. En particular, la actividad reproductiva de los anuros que habitan las zonas tropicales secas se ve afectada por las lluvias, que determinan la disponibilidad y calidad de los sitios de reproducción. En este estudio, se analizó la distribución espacial y temporal de los anuros en un bosque tropical seco en el oeste de México durante dos temporadas de lluvias (10 de julio- 4 de octubre 2013 y 26 de junio- 26 de septiembre 2014). Se tomaron datos sobre la presencia de 15 especies de anuros con reproducción acuática en cuatro arroyos temporales y su relación con la precipitación, la humedad y la temperatura. Se determinó la riqueza, abundancia y diversidad de especies en cada arroyo; así como, las diferencias en las estrategias de reproducción y el uso de microhábitats por cada especie. Las especies más abundantes fueron: Tlalocohyla smithii y Exerodonta smaragdina, mientras que las menos abundantes fueron Leptodactylus melanonotus e Incilius mazatlanensis. La mayor riqueza, abundancia y actividad reproductiva se registró en el arroyo con el mayor número de sitios para la reproducción (charcas). Encontramos una segregación temporal en la presencia y actividad reproductiva de las especies que se asoció principalmente con la precipitación. También se observó una superposición de especies en algunas semanas durante la temporada de lluvias. La mayoría de las especies utilizaron sustratos específicos para determinadas actividades (por ejemplo, puesta de huevos), pero utilizaron una variedad de microhábitats para otras actividades (por ejemplo, vocalización). Discutimos estas diferencias de comportamiento como factores que facilitan la coexistencia de estas especies de anuros en este ambiente durante la estación lluviosa.

Reproductive features of the swimming crab Callinectes danae(Crustacea, Portunoidea) on the subtropical coast of Brazil: a sampling outside the estuary / Características reprodutivas do siri Callinectes danae(Crustacea, Portunoidea) na região subtropical da costa do Brasil: uma amostragem fora do estuário

AbstractThe life cycle of the crab Callinectes danae is estuarine-dependent, and studies on aspects of their biology should also cover marine areas. The present study investigated the sexual maturity, as well as habitat preference by adults in different gonadal stages, and the crabs’ reproductive periodicity outside the estuary. Three bays on the subtropical southeastern coast of Brazil were sampled monthly for two years. For each bay, six transects were established, four of them parallel to the beach line (5, 10, 15 and 20 m depth), as well as one transect in an exposed area, and another sheltered from the action of waves. The results showed that the pattern of spatio-temporal distribution of adults C. danae was similar in three bays, although the highest abundance was found in Ubatumirim. Females with developed gonads/ovigerous females were found in greater abundance than females with rudimentary/developing gonads, mainly in deeper transects. Although the areas sampled have different environmental characteristics, the reproductive pattern of the species did not change, showing continuous reproduction throughout, with more abundance of reproductive females on spring and summer. Males reached maturity at larger sizes than females in all three bays.

ResumoO siri Callinectes danae é estuarino dependente em seu ciclo de vida, sendo que os estudos que levantam informações sobre os aspectos da sua biologia devem também abranger regiões marinhas. Assim, o presente estudo teve como objetivo investigar a maturidade sexual, bem como a preferência ocupacional por adultos em diferentes estágios gonadais e sua periodicidade reprodutiva fora da região estuarina. Para tanto, três enseadas da porção subtropical do litoral sudeste brasileiro foram amostradas mensalmente, durante dois anos. Para cada enseada, seis transectos foram estabelecidos, quatro deles paralelos à linha de praia (5, 10, 15 e 20m de profundidade), um transecto exposto e outro abrigado à ação de ondas. Os resultados mostraram que o padrão de distribuição espaço-temporal de adultos de C. danae foi similar nas três enseadas, embora uma maior abundância tenha sido encontrada em Ubatumirim. Fêmeas ovígeras e com gônadas desenvolvidas foram encontradas em maior abundância que fêmeas com gônadas rudimentares e em desenvolvimento, principalmente nos transectos mais profundos. Apesar das regiões amostradas possuírem características ambientais diferenciadas, o padrão reprodutivo da espécie não sofreu alterações, apresentando reprodução contínua, com maior abundância de fêmeas reprodutivas na primavera e verão. Machos atingiram maturidade em tamanhos maiores que as fêmeas nas três enseadas.

Ecología reproductiva de Geobatrachus walkeri (Anura: Srabomantidae) / Reproductive ecology of Geobatrachus walkeri (Anura: Strabomantidae)

Geobatrachus walkeri is a frog that belongs to a monotypic genus and is endemic to the Sierra Nevada de Santa Marta, Colombia. The species inhabits different microhabitats between 2 000 to 3 500m altitude, including the leaf litter of a pine plantation. To understand its reproductive ecology, we conducted eight frog samplings, covering the rainy and dry seasons, and two habitat types (secondary native forest and pine plantation) during 2010-2011. For this study, we also included data obtained from five previous similar samplings undertaken during 2008-2009. The pine leaf litter was the main microhabitat where frogs were found; we heard choruses of six-ten calling males during all sampled months, and observed the frogs having diurnal and nocturnal activity. Regardless of the year of study, the population consisted of neonates recruited several times of the year, a large number of juveniles with a wide range of body sizes, and fewer adults with a narrower range of body size. The histological analyses of the gonads showed that the size at maturity was near 18mm SVL for males and females, and those adult males and females were reproductive active during all sampling months, suggesting a continuous reproductive activity pattern. However, during the dry season, the seminiferous tubules showed a drastically diminished spermatic epithelium although containing abundant luminal spermatozoa, which suggest a reduction in the sperm production at the end of this season. Similarly, frogs of all age categories were significantly more abundant during the early dry season, whereas were significantly less abundant with the advancement of the dryness suggesting that the intensity of the dry season could temporally stop the activity and reproduction of this population.

Geobatrachus walkeri es una rana que pertenece a un género monotípico y es endémica de la Sierra Nevada de Santa Marta, Colombia. La especie habita en diferentes microhábitats entre los 2 000 y 3 500m de altitud, incluyendo la hojarasca de una plantación de pinos. Para entender su ecología reproductiva se realizaron ocho muestreos de individuos, que abarcaron las estaciones de lluvias y de sequía y dos tipos de hábitats (bosque secundario y plantación de pino) durante 2010-2011. También se incluyeron los datos de cinco muestreos similares obtenidos previamente durante el período 2008-2009. El principal microhábitat donde las ranas se encontraron fue la hoja-rasca de pino, allí escuchamos coros de seis-diez machos durante todos los meses muestreados, y observamos que las ranas tienen actividad diurna y nocturna. Sin importar el año de estudio, la población se compone de neonatos reclutados en varios meses del año, un gran número de juveniles con un amplio rango de tamaños corporales, y un menor número de adultos con un rango más reducido de tamaño corporal. Los análisis histológicos de las gónadas mostraron que el tamaño a la madurez se adquiere cerca de los 18mm LRC para machos y hembras, y que los machos y hembras adultos fueron reproductivos durante todo el muestreo, lo que sugiere un patrón continuo de actividad reproductiva. Sin embargo, durante la estación seca, los túbulos seminíferos presentan un epitelio espermático drásticamente disminuido, aunque contienen abundantes espermatozoides luminales, lo que sugiere una reducción en la producción de espermatozoides en el final de la estación seca. Del mismo modo, las ranas de todas las categorías de edad fueron significativamente más abundantes durante el inicio de la estación seca, mientras que fueron significativamente menos abundantes con el avance de la sequedad, lo que sugiere que una mayor intensidad de la temporada de sequía podría detener temporalmente la actividad y la reproducción en esta población.

Progesterona plasmática de ovelhas submetidas ao efeito-macho e mantidas sob diferentes condições nutricionais / Plasmatic progesterone of ewes submitted to male effect and kept at different nutritional conditions

Dosou-se a concentração plasmática de progesterona (P4) em ovelhas Santa Inês (SI), Suffolk (SU) e Romney Marsh (RM) em anestro sazonal e submetidas ao efeito-macho, as quais receberam ou não suplementação alimentar. Machos vasectomizados foram introduzidos no grupo de fêmeas após um período prévio de isolamento de 60 dias, e amostras de sangue foram colhidas antes e após a introdução dos machos. Houve efeito (P<0,01) de período, raça, interação período x raça e interação suplementação x período x raça sobre a concentração de P4. Nas ovelhas SI ocorreu aumento (P<0,01) da concentração de P4 após a introdução do macho, indicando que houve aumento na atividade cíclica reprodutiva desse grupo. A suplementação, neste caso, potencializou este aumento. Nas ovelhas SU e RM não ocorreram modificações na concentração de P4 (P>0,01) após a introdução dos machos, nem houve efeito de suplementação. O efeito-macho foi eficaz em induzir a atividade reprodutiva durante o anestro sazonal em ovelhas SI, mas não em ovelhas SU e RM, e a associação dessa prática com a suplementação alimentar é recomendada para ovelhas da raça nativa SI.

The present study aimed to verify the plasmatic progesterone (P4) concentrations in Santa Inês (SI), Suffolk (SU) and Romney Marsh (RM) ewes submitted to male effect receiving or not food supplementation during seasonal anestrous. Vasectomized rams were introduced to the group of ewes after 60 day isolation. Blood samples were collected before and after the male's introduction. Effects (P<0.01) of period, breed, period x breed interaction and period x breed x supplementation interaction on plasmatic P 4 concentrations were observed. The plasmatic P 4 concentrations of SI ewes increased (P<0.01) after the male introduction, indicating there was an increase in the reproductive activity in this group. Supplementation increased this effect. For SU and RM ewes the plasmatic P 4 concentrations did not alter (P>0.01) after the male introduction, with no supplementation. It was concluded the male effect was efficient in inducing the reproductive activity in SI ewes, but not in SU and RM ewes. The association of the effect of the male with supplementation increased this effect.

Impact of Taraxerol in combination with extract of Euphorbia tirucalli plant on biological parameters of Lymnaea acuminata / Impacto do Taraxerol em combinação com o extrato da planta de Euphorbia tirucalli nos parâmetros biológicos da Lymnaea acuminata

The present work was carried out to evaluate the molluscicidal activity of active ingredient Taraxerol with the acetone extract of Euphorbia tirucalli against Lymnaea acuminata snail. The (fecundity, hatchability and survivability) of snail L. acuminata exposed to this extract was studied. The effects of the tested extracts on life-history traits of harmful snail L. acuminata have also been evaluated, and this study also expounds the inhibitory effects of these extracts singly as well as in binary combination (1:1 ratio). It concluded that these herbal products act as a potential source of molluscicides, and that they would also have the advantage of easy availability, low cost, biodegradability and greater acceptance amongst users than synthetic pesticide.

O presente trabalho foi levado a efeito para avaliar a atividade moluscicida do ingrediente ativo Taraxerol junto com o extrato de acetona da Euphorbia tirucalli contra o caramujo Lymnaea acuminata. Foram estudados a fecundidade, o desenvolvimento e sobrevivência do caramujo Lymnaea acuminata exposto a estes extratos. Os efeitos danosos destes extratos testados na vida do caramujo L. acuminata foram também avaliados e este estudo demonstra os efeitos inibidores destes extratos isolados ou em combinação binária (relação l:1). Concluiu-se que estes produtos vegetais agem como fontes potenciais de moluscicidas e que eles também têm a vantagem de obtenção fácil, baixo custo, biodegradabilidade e maior aceitação entre os usuários do que os pesticidas sintéticos.

Reproductive activity alterations on the Biomphalaria glabrata exposed to Euphorbia splendens var. hislopii latex

The reproductive activity of Biomphalaria glabrata exposed to Euphorbia splendens var. hislopii latex was evaluated. Parameters related to fecundity and fertility were observed. The snails were exposed to the LD50 (1 mg/l) of crude latex. At the first week post exposure (p.e.), the egg laying was reduced. After the fourth week p.e., an increase of the number of eggs/snail occurred. The results showed a marked reduction in the hatching of the snails, revealing an interference of latex exposure with the reproductive process of B. glabrata of E. splendens var. hislopii. The LD50 of the latex may be used as an alternative method to control the size of the populations of B. glabrata in field.

Compare Reproductive Activity of Diabetic Rat Pancreatic Stem Cells with that of Normal Rat's Pancreatic Stem Cell / 医学研究杂志

Objective Compare the reproductive activity of pancreatic stem cells isolated from diabetic rat with that of normal rat to assess the effect of microenvirement on stem cells'proliferation.Methods Diabetic rat model were prepared by peritoneal injecting 60mg/kg streptozotocin.Pancreata from 10 diabetic rats and 10 normal rats were trimmed and digested into single cells which were then inoculated onto the culture plate respectively.After passaging 3 generation the cells were identified by nestin immunostaining.During culturing the cell growth curve was observed and the cell cycle of the third and seventh generation cultured cells was evaluated by flow cytometry.Results After passaging pancreatic stem cells was purified and identified by nestin immunostaining.The reproductive activity of diabetic rat was much better[ratio of s stage:(20.7?2.7)% vs(14.1?2.5)%,P0.05].Conclusions The stem cells are stimulated to proliferate after islet injure.The reproductive activity of cells can be provoked by the microenvironment.