Gonadal differentiation during embryonic and fetal development of male New Zealand rabbits (Oryctolagus cuniculus) / Diferenciación gonadal durante el desarrollo embrionario y fetal de conejos machos neozelandeses (Oryctolagus cuniculus)

SUMMARY: The rabbit is considered an ideal animal model for studies that describe abnormalities in the testicles due to the similar morphogenetic mechanisms of sexual development and diseases commonly found in humans. The aim of this study was to determine the male sexual differentiation of the New Zealand rabbit (Oryctolagus cuniculus) through development. The gestational age was estimated and classified as 9, 12, 14, 16, 18, 20, 23 and 28 gestational days. The morphological and sexual determination were performed by histological analysis of the reproductive tract in the embryos and fetuses (9-28 days) as well as by immunohistochemistry- Desert hedgehog-Dhh- (testis-specific protein on Y chromosome- 16, 20, 23 days and adult rabbits). Gonads were observed from the 14th day in an undifferentiated stage and with homogeneous aspect. Sexual differentiation was observed from the 16th day with presence of cells forming gonadal cords and Dhh+ cells in the gonadal parenchyma. From the 18th gestational day testicular cords were observed, which evolved into organized seminiferous tubules. The formation of the efferent ducts and ductus deferens and epididymis was observed on the 20th and 23rd days, respectively. The differentiation of the external genitalia occurred from the 23rd days from the anogenital distance and was identified to identify the penile structures. In summary, the features of the sexual differentiation were determined by observation of the Dhh+ protein in embryos from the 16th day to adulthood, and the morphological particularities observed from the 18th gestational day, determined by differentiation of the external genitalia from the 23rd day.

RESUMEN: El conejo se considera un modelo animal ideal para estudios que describen anomalías a nivel testícular debido a que presenta mecanismos morfogenéticos similares al desa- rrollo sexual y enfermedades que se encuentran comúnmente en los seres humanos. El objetivo de este estudio fue determinar la diferenciación sexual masculina del conejo de Nueva Zelanda (Oryctolagus cuniculus) a través del desarrollo. La edad gestacional se estimó y clasificó en 9, 12, 14, 16, 18, 20, 23 y 28 días gestacionales. La determinación morfológica y sexual se realizó mediante análisis histológico del tracto reproductivo en los embriones y fetos (9 - 28 días) así como mediante inmunohistoquímica -Desert hedgehog-Dhh- (proteína testicular específica en el cromosoma Y- 16, 20, 23 días y conejos adultos). Las gónadas se observaron a partir del día 14 en un estadio indiferenciado y con aspecto homogéneo. Se observó diferenciación sexual a partir del día 16 con presencia de células formadoras de cordones gonadales y células Dhh+ en el parénquima gonadal. A partir del día 18 de gestación se observaron cordones testiculares, que evolucionaron a túbulos seminíferos organizados. La formación de los conductos eferentes, deferentes y del epidídimo se observó a los 20 y 23 días, respectivamente. La diferenciación de los genitales externos ocurrió a partir del día 23 desde la distancia anogenital y se utilizó para identificar las estructuras del pene. En conclusión, las características de la diferenciación sexual se determinaron mediante la observación de la proteína Dhh en embriones desde el día 16 hasta la edad adulta, y las particularidades morfológicas observadas a partir del día 18 de gestación, determinadas por diferenciación de los genitales externos a partir del día 23.

Gonadal maturation in Pseudoplatystoma metaense x Leiarius marmoratus hybrids, (Siluriformes: Pimelodidae) / Maduración gonadal en híbridos de Pseudoplatystoma metaense x Leiarius marmoratus (Siluriformes: Pimelodidae)

SUMMARY: Establishing guidelines for responsible management in fish production systems requires knowledge of the basic biology of the fish to be raised. The objective of this work was to determine the reproductive capacity of hybrids produced from the crossing of females of Pseudoplatystoma metaense with males of Leiarius marmoratus. Males presented a digitiform, unrestricted spermatogonial testicle containing caudal digits producing glycoproteins that do not form a seminal vesicle. It was possible to find free sperm in the lumen of the tubules and in the ducts. The ovary of the females was found to be saccular and synchronous with at least three groups of oocytes. In the first year of life, only oogonia up to previtellogenic oocytes (cortical alveolus 284.9 ± 35.7 mm in diameter) were found. After the second year vitellogenic oocytes 730 ± 3.78 mm in diameter were observed. The events of gonadal development of the hybrids indicate that they are gonochoric, synchronic animals. The maturation peaks in the high-water season, overlapping with the parental species. Therefore, the escape of hybrids from fish cultures to the rivers may increase the risk of crosses, gene introgression, or diminution of the reproductive capacity of the pure species.

RESUMEN: El establecimiento de pautas para la gestión responsable en los sistemas de producción de peces requiere el conocimiento de la biología básica de los peces a criar. El objetivo de este trabajo fue determinar la capacidad reproductiva de los híbridos producidos por el cruce de hembras de Pseudoplatystoma metaense con machos de Leiarius marmoratus. Los machos presentaron un testículo espermatogonial digital no restringido que contiene dígitos caudales que producen glucoproteínas que no forman una vesícula seminal. Fue posible encontrar esperma libre en la luz de los túbulos y en los conductos. Se encontró que el ovario de las hembras era sacular y sincrónico con al menos tres grupos de ovocitos. En el primer año de vida, solo se encontraron oogonia hasta ovocitos previtelogénicos (alvéolo cortical de 284,9 ± 35,7 mm de diámetro). Después del segundo año, se observaron ovocitos vitelogénicos de 730 ± 3,78 mm de diámetro. Los eventos de desarrollo gonadal de los híbridos indican que son animales sincrónicos gonocóricos. La maduración alcanza su punto máximo en la temporada de aguas altas, superponiéndose con las especies parentales. Por lo tanto, el escape de híbridos de cultivos de peces a los ríos puede aumentar el riesgo de cruces, introgresión genética o disminución de la capacidad reproductiva de las especies puras.

Reproductive biology of Hyphessobrycon eques (Characiformes: Characidae) in Southern Pantanal, Brazil / Biologia Reprodutiva de Hyphessobrycon eques (Characiformes: Characidae) no Pantanal Sul, Brasil

Abstract Population and reproductive aspects allow the knowledge and understanding of population dynamics and the influence of environmental factors, in addition to ensure the success of a species continuity. Thus, the aim of this study was to analyze population and reproductive traits of the species Hyphessobrycon eques in southern Pantanal, Brazil. Monthly samplings were conducted from February/2009 to January/2011, with 617 individuals analyzed, being 365 females and 262 males. A similar form of distribution in length and weight between the sexes was observed. There was no significant variation in sex ratio over time, with higher proportion of females during the entire sampled period. Both sexes presented a angular coefficient of Weight/Length (b) relationship greater than 3, with speed of increase in weight greater than in length. For females, a long reproductive period was observed, with greater reproductive intensity from January through June. No significant correlation was observed between the Gonadosomatic Index (GSI) and the average temperature, rainfall and river level, despite the fact that reproductive activity occurs in autumn/winter, when there are favorable conditions due to flooding. The size at first maturation (L50) was 20.2 mm, with confidence interval varying from 19.7 through 20.7 mm. The average fecundity was 191.9 oocytes/females and was significantly related to the standard length and total weight (g), demonstrating a relation with energy accumulation to invest in reproduction. The long reproductive period, intensified by partial spawning, higher proportion of females and low L50, show that the species has strategies necessary for survival and rapid population growth, common in small species characterized as r-strategists.

Resumo Os aspectos populacionais e reprodutivos permitem o conhecimento e a compreensão da dinâmica populacional e da influência de fatores ambientais, assegurando o sucesso da continuidade de uma espécie. Desta forma, o presente trabalho teve como objetivo analisar os traços populacionais e reprodutivos da espécie Hyphessobrycon eques no Sul do Pantanal, Brasil. Foram realizadas amostragens mensais de Fevereiro/2009 a Janeiro/2011, com um total de 617 indivíduos analisados, sendo 365 fêmeas e 262 machos. Foi observada que a distribuição foi similar em comprimento e peso entre os sexos. Não ocorreu variação significativa na proporção sexual ao longo do tempo, com maior proporção de fêmeas durante todo período amostrado. Ambos os sexos apresentaram um coeficiente angular da relação Peso/Comprimento (b) maior que 3, com velocidade do incremento em peso maior do que em comprimento. Para as fêmeas, foi observado um período reprodutivo longo, com maior intensidade reprodutiva de Janeiro e Junho. Não foi observada correlação significativa entre o Índice Gonadossomático (IGS) e a temperatura média, pluviosidade e nível do rio, apesar de ocorrer atividade reprodutiva no outono/inverno, período que há condições favoráveis decorrentes da inundação. O tamanho de primeira maturação (L50) foi de 20,2 mm, com intervalo de confiança variando entre 19,7 e 20,7 mm. A fecundidade média foi de 191,9 ovócitos/fêmea e esteve relacionada significativamente ao comprimento padrão e peso total (g), demonstrando uma relação com acúmulo de energia para investir na reprodução. O período reprodutivo longo, intensificado pela desova parcelada, maior proporção de fêmeas e baixo L50, mostram que a espécie possui estratégias necessárias para sobrevivência e rápido crescimento da população, comum em espécies de pequeno porte caracterizadas como r-estrategistas.

Descrição morfológica dos ovários do peixe Melanotaenia boesemani em atividade reprodutiva / Morphological description of Melanotaenia boesemani ovaries in reproductive activity

Estudou-se o tecido germinativo ovariano do peixe Melanotaenia boesemani. Por meio de análises morfológicas das gônadas, realizadas após a confecção de lâminas histológicas elaboradas em parafina e coradas com hematoxilina-eosina, foram descritos os tipos celulares encontrados e realizada a classificação do estádio de maturidade dos peixes. Macroscopicamente, foi identificado que a referida espécie possui ovário único, arredondado e, na fase observada, amarelado, localizado na parte látero-anterior da cavidade celomática. As fêmeas analisadas foram classificadas na escala de desenvolvimento gonadal como maduro/em reprodução. A presença de folículos vazios e marcas de desova nas lamelas ovulígeras mostrou-se evidente. Nos ovócitos vitelogênicos deste peixe, foi constatada a presença de filamentos de adesão ovocitária ancorados à zona pelúcida. Os ovários apresentaram aspecto morfológico geral semelhante ao de outros peixes teleósteos. Seu tipo de desova foi classificado como intermitente e o padrão de desenvolvimento de ovócitos, como assincrônico.(AU)

The germinal ovarian tissue of the fish Melanotaenia boesemani was studied. By means of morphological analyses of the gonads, performed after the manufacture of histological slides made of paraffin and stained with hematoxylin-eosin, the cell types found were described and the rank of the maturity stage of the fishes was executed. Macroscopically was found that the species has only one ovary, rounded and in the observed phase yellowish, located in the lateral front part of the coelomic cavity. The observed females were classified in the gonadal development scale as mature/in reproduction. The presence of empty follicles and spawning marks on ovigerous lamellae proved to be evident. In vitellogenic oocytes of this fish, the presence of filaments of oocyte adhesion anchored to the pellucida zona was found. The ovaries showed general morphological appearance similar to that of other teleost fishes. Its spawning type was classified as intermittent and the pattern of development of oocytes as asynchronous.(AU)

Reproductive periods of Lucina pectinata (BIVALVE; LUCINIDAE) in the Paranaguá Estuarine Complex, Paraná - Brazil / Período reprodutivo de Lucina pectinata (BIVLAVE; LUCINIDAE) no Complexo Estuarino de Paranaguá, PR - Brasil

Abstract The objectives of the present study is to describe the size for exploitation and gonadal maturation of L. pectinata in Peças Island in Paraná coast. Twenty two individuals were sampled every month, from an intertidal flat of the Peças River, Municipality of Guaraqueçaba, during two periods – summer/autumn and winter of the 2009. Environmental parameter data was obtained at the same time of the biological sampling: temperature, salinity and seawater transparency at the Peças River mouth. The animals’ height, length, width, gross weight, wet weight of meat and dry weight of meat were measured at the lab. The gonad development stages (GDS), condition index (CI) and yield index (Y) were calculated. Sex identification was conducted by direct observation of the gonads and gametes under an optic microscope. Individuals were classified as males (M), females (F) or undetermined (U). The medium height observed was of 49.62 ± 6.84 mm. Period of more expressive gonad repletion were observed in summer when water temperature was higher. Results of GDS in both periods showed a predominance of partially filled gonad stages. This may be related with the fact that L. pectinata has intense gametogenesis activity, that is, the organisms do not have a resting interval, but go back to gonad restructuring rapidly after releasing the gametes. The continuity of the reproductive cycle of the specimens found in both studied periods could demonstrate a possible continuous reproduction of the species and a size for exploitation above 40.00 mm of height.

Resumo O presente estudo tem como objetivo descrever o tamanho de exploração e a maturação gonadal de L. pectinata na Ilha das Peças no litoral do Paraná. Vinte e dois indivíduos foram amostrados mensalmente na região entre-marés no Rio das Peças, Município de Guaraqueçaba, durante 2 períodos – verão/outono e inverno de 2009. Paralelamente às amostragens, foram obtidos dados dos parâmetros ambientais: temperatura, salinidade e transparência da água do mar na foz do Rio das Peças. A altura, comprimento, largura, peso bruto, peso úmido da carne e peso seco da carne dos animais foram medidos no laboratório. Foram calculados os estágios de desenvolvimento gonadal (EDG), índices de condição (IC) e de rendimento (R). A Identificação do sexo foi realizada por observação direta das gônadas e gametas sob microscópio óptico. Os indivíduos foram classificados como: machos (M), fêmeas (F) ou indeterminados (I). A altura média observada foi de 49,62 ± 6,84 mm. O período de maior repleção gonadal foi observado no verão, quando a temperatura da água foi mais elevada. Resultados dos EDG em ambos os períodos mostrou um predomínio de gônadas parcialmente cheias. Isso pode estar relacionado com o fato de que L. pectinata tem atividade gametogênese intensa, ou seja, os organismos não têm um intervalo de repouso, mas voltam a reestruturação das gônadas rapidamente após liberação dos gametas. A continuidade do ciclo reprodutivo dos espécimes encontrados em ambos os períodos estudados, pode demonstrar possível reprodução contínua da espécie e tamanho de exploração superior a 40,00 mm de altura.

Desenvolvimento sexual e maturação puberal / Sexual and puberal development

Os fenômenos do desenvolvimento sexual e puberal são eventos progressivos e coordenados. Dependem de fatores cromossômicos - gênicos, gonadais e hormonais. Tais eventos nos indivíduos do sexo masculino e feminino, sendo sincrônicos, permitirão um conveniente desenvolvimento sexual e puberal. Analisar tais fenômenos é o propósito deste estudo.(AU)

The sexual and puberal modifications are coordinate and progressive during differents life phases. Many factors are involved like genic-chromosomic, gonadal and hormonal. Those events that occurred in males and females are synchronous and to create a perfect development. Our proposal is review those situations.(AU)

Histological validation of morphochromatically-defined gonadal maturation stages of green abalone (Haliotis fulgens) Philippi,1845 and pink abalone (Haliotis corrugata) Wood, 1828 / Validación histológica de las fases morfocromáticas de maduración gonádica del abulón azul (Haliotis fulgens) Philippi, 1845 y del abulón amarillo (Haliotis corrugata) Wood, 1828

Identifying the maturity stage of specimens is essential for the determination of the spawning season, which in turn facilitates the formulation of adequate fisheries management measures for the sustainable use of sea resources, such as abalone. This study aims to validate, based on histological evidence, a gonad maturation scale that encompasses four morphochromatically-defined stages (developing, maturity, spawning and resting) for females and males, plus an additional stage for reproductively inactive (undifferentiated) specimens, to be used as an identification key. Given the similarity between Haliotis fulgens and Haliotis corrugata as to their morphochromatic features, the gonadal maturation scale can be used for both species.

La determinación de la fase de madurez es importante para identificar la temporada de desove y permitir establecer medidas de manejo pesquero para el aprovechamiento responsable de los recursos como el abulón. El presente trabajo valida histológicamente una escala de maduración gonádica a manera de guía de identificación, que consiste de cuatro fases morfocromáticas para hembras y machos (desarrollo, madurez, desove y reposo), y un estadio para los organismos reproductivamente inactivos (indiferenciado). Dada la similitud entre las características morfocromáticas de Haliotis fulgens y Haliotis corrugata, la escala de maduración gonádica puede ser utilizada indistintamente.

Gonad development and reproduction of the ballyhoo half beak, Hemiramphus brasiliensis from the coastal waters of Rio Grande do Norte, Brazil / Desenvolvimento das gônadas e reprodução da agulha-preta, Hemiramphus brasiliensis das águas costeiras do Rio Grande do Norte, Brasil

The gonad development and reproductive aspects of Hemiramphus brasiliensis from the coastal waters of Rio Grande do Norte, Brazil were verified. This paper presents data on the length-weight relationship, sex ratio, length at first sexual maturity, gonad development, reproductive period and fecundity of H. brasiliensis. Females of this species predominated in the sampled population and were larger in size than the males. The length at the first sexual maturation of males was 20.8 cm and that of females was 21.5 cm. The macroscopic characteristics of the gonads indicated four maturation stages. Histological studies of gonads of H. brasiliensis showed six phases of oocyte development and four phases of spermatocyte development. The batch fecundity of this species is 1153 (±258.22) oocytes for 50 g body weight of female. The microscopic characteristics of gonad development indicate that H. brasiliensis is a multiple spawner, with active reproductive period during the months of January to June and October. The reproductive period of this species is independent of the rainy period of the region.

O desenvolvimento das gônadas e os aspectos reprodutivos de Hemiramphus brasiliensis nas águas costeiras do Rio Grande do Norte, Brasil foram verificados. Este trabalho apresenta dados sobre a relação peso-comprimento, proporção sexual, comprimento de primeira maturação sexual, desenvolvimento gonadal, período reprodutivo e fecundidade de H. brasiliensis. As fêmeas de H. brasiliensis predominam na população amostrada e foram maiores em tamanho do que os machos. O comprimento da primeira maturação sexual dos machos foi de 20,8 cm e das fêmeas foi de 21,5 cm. As características macroscópicas das gônadas indicam quatro estádios de maturação. Estudos histológicos de gônadas de H. brasiliensis mostraram seis fases de desenvolvimento do ovócito e quatro fases de desenvolvimento de espermatócitos. A fecundidade por lote desta espécie foi 1,153 (± 258,22) ovócitos por 50 g de peso corporal da fêmea. As características microscópicas de desenvolvimento das gônadas indicam que H. brasiliensis apresenta desova múltipla, com um período de atividade reprodutiva nos meses de janeiro a junho e outubro. O período reprodutivo de H. brasiliensis é independente das chuvas da região.

Pineal gland plays a role in gonadal development after eyelids separation in puppies / La glándula pineal juega un rol en el desarrollo gonadal luego de la separación de los párpados en cachorros

Several functional and morphological studies have been conducted on the pineal gland in many mammalian species; however, no published reports are available on the role of pineal gland on the gonadal development before and after eyelids separation in puppies. Therefore, this study aimed to trace the postnatal histo-morphological changes in the pineal gland and gonads of puppies before (2, 10 and 11 days old) and after (25, 35 and 40 days old) eyelids separation in an attempt to investigate the possible role of pineal gland on the gonadal development. In general, the differentiation of pineal cells, interstitial endocrine cells of testes and stromal ovarian cells coincides with the start of eyelids separation in puppies. Histological examination of stained pineal and gonadal slices of puppies after eyelids separation revealed a remarkable differentiation of pinealocytes and testicular interstitial endocrine cells, as well as presence of some evidence of folliculogenesis in ovary. Surprisingly, melatonin receptor (MT1) protein expression levels were significantly increased in the ovaries and testes of puppies after eyelids separation. Moreover, the mRNA and protein expression of AANAT, a rate-limiting enzyme in melatonin biosynthesis, was notably increased in the pineal gland of opened eyes puppies. Our results suggest an increase of melatonin production from the pineal gland of opened eyes puppies and this could play a vital role in the developmental changes observed in the gonads of these puppies.

Diversos estudios morfológicos y funcionales han sido realizados sobre la glándula pineal en distintas especies de mamíferos. Sin embargo, no hay informes publicados acerca del rol de la glándula pineal en el desarrollo gonadal antes y después de la separación de los párpados en cachorros. Este estudio tuvo como objetivo trazar los cambios histo-morfológicos postnatales en la glándula pineal y las gónadas de los cachorros antes (2, 10 y 11 días de edad) y después (25, 35 y 40 días de edad) de la separación de los párpados, en un intento por investigar el posible rol de la glándula pineal en el desarrollo gonadal. En general, la diferenciación de los pinealocitos, células intersticiales endocrinas de los testículos y las células estromales del ovario coincide con el inicio de la separación de los párpados en cachorros. El examen histológico de glándula pineal y los cortes gonadales de los cachorros, después de la separación de los párpados, reveló una notable diferenciación de los pinealocitos y las células intersticiales endocrinas testiculares, así como la posible evidencia de foliculogénesis en el ovario. Sorprendentemente, en el receptor de melatonina (MT1) los niveles de expresión de proteínas fueron significativamente superiores en los ovarios y los testículos de los cachorros después de la separación de los párpados. Además, el ARNm y la expresión de la proteína AANAT, una enzima limitante de la velocidad en la biosíntesis de la melatonina, aumentaron notablemente en la glándula pineal de los cachorros con los ojos abiertos. Nuestros resultados sugieren que existe un aumento de la producción de melatonina por parte de la glándula pineal en los cachorros con los ojos abiertos, lo que podría jugar un rol vital en los cambios evolutivos observados enlas gónadas de estos cachorros.

Reproductive aspects of the flyingfish, Hirundichthys affinis from the Northeastern coastal waters of Brazil / Aspectos reprodutivos do peixe voador, Hirundichthys affinis das águas costeiras do Nordeste do Brasil

The epipelagic flyingfish, Hirundichthys affinis is a major artisanal fishery resource from the Northeastern coastal waters of Brazil. However, biological information about this species has been poorly documented. This paper presents data on the length-weight relationship, sex ratio, length at first sexual maturity, gonadal development and fecundity of H. affinis sampled from the coastal waters of Rio Grande do Norte, Brazil. The total body length and weight for both sexes ranged from 23.4 to 29.4 cm and from 89 to 188g, respectively. The allometric coefficient of males was 2.208 and that of females was 2.985, indicating negatively allometric growth. The sex ratio was 1M:1.6F thus differing from the expected ratio of 1:1 (χ2 = 18.63). The total length at first sexual maturity was estimated at 27.3 cm for males and 27.1 cm for females. The macroscopic characteristics of the gonads indicated four maturation stages. Histological studies of gonads of H. affinis showed seven phases of oocyte development and four phases of spermatocyte development. The mean absolute fecundity was 9092 vitelogenic oocytes. Spawning occurred during the months of March to July. The microscopic descriptions of the stages of gonad maturation indicate that the study area is an important spawning ground of H. affinis.

O peixe epipelágico voador, Hirundichthys affinis é um importante recurso de pesca artesanal das águas costeiras do Nordeste do Brasil. No entanto, as informações biológicas sobre esta espécie tem sido pouco documentada. Este trabalho apresenta dados sobre a relação peso-comprimento, proporção sexual, comprimento de primeira maturação sexual, desenvolvimento gonadal e fecundidade de H. affinis amostrados das águas costeiras do Rio Grande do Norte, Brasil. O comprimento total e o peso total de ambos os sexos variaram 23,4-29,4 cm, e de 89 a 188g, respectivamente. O coeficiente alométrico dos machos foi de 2,208 e o de fêmeas foi 2,985, indicando um crescimento alométrico negativo. A proporção entre os sexos foi 1M:1.6 F, diferindo da proporção esperada de 1:1 (χ2 = 18.63). O comprimento total da primeira maturação sexual foi estimado em 27,3 centímetros para os machos e 27,1 cm para as fêmeas. As características macroscópicas das gônadas indicaram quatro estádios de maturação. Estudos histológicos das gônadas de H. affinis mostram sete fases de desenvolvimento do ovócito e quatro fases de desenvolvimento do espermatócito. A fecundidade absoluta média foi de 9.092 ovócitos vitelogênicos. A desova ocorreu durante os meses de março a julho. As descrições microscópicas dos estágios de maturação gonadal indicam que a área de estudo é uma importante área de desova de H. affinis.

Growth stanzas in an Epinephelidae-Lutjanidae complex: considerations to length-weight relationships / Etapas de crecimiento en un complejo Epinephelidae-Lutjanidae: consideraciones al cálculo de las relaciones peso-longitud

Growth stanzas or abrupt changes in growth rates are present throughout the life span of fish. Identifying growth stanzas will help to adequately described growth taking into account that fishes are indeterminate growers. In this study, we used length-weight (L-W) relationships to analyze the growth stanzas in the Grouper-Snapper complex of Southern Gulf of Mexico. For this, the type of sexuality, sex and different sexual maturity phase were considered in the analyses of three species of gonochoric Snappers (Lutjanidae) and six species of protogynous hermaphrodite Groupers (Epinephelidae). Welch ANOVA tests were carried out to determine the existence of differences in length and weight between juveniles and adults per sex. According to the observed differences, L-W relationship parameters (a and b), standard error (SE b) and coefficients of determination (R2) were calculated for all species separately by sex and sexual maturity phase. Snappers’ juvenile-females b-value ranged from 2.44-2.77, juvenile-males from 2.16-2.94, adult-females from 2.63-2.80 and adult-males from 2.63-2.98. Groupers’ b-value ranged for juvenile-females 2.66-3.20, adult-females from 2.73-3.31 and for adult-males 2.93-3.29. For each relationship b-value was t-tested (t-Student) to explore differences from the allometric coefficient (b=3), which indicated changes in body form. Hypothesis test, for regression slopes (b) between Snappers’ juvenile-females vs. adult-females and juvenile-males vs. adult-males and Groupers’ juvenile-females vs. adult-females and adult-females vs. adult-males, indicated different growth stanzas related to gonadal development for Snappers, and to gonadal development and sex change in Groupers. The identification of growth stanzas is crucial to avoid an overestimation or misleading growth rate which is used in fisheries management to establish some target reference points, such as maximum sustainable yield or yield-per-recruit.

Distintos estados o estanzas de crecimiento descritos por cambios en el ritmo de crecimiento, se pueden observar en peces a lo largo de su vida ya que presentan crecimiento indeterminado. A través del análisis de relaciones longitud-peso (L-P), se identificaron distintas estanzas de crecimiento considerando el tipo de sexualidad, sexo y madurez sexual de individuos de tres especies de pargos (Lutjanidae) gonocóricos y seis de meros (Epinephelidae) hermafroditas protóginos. Pruebas independientes de ANOVA de Welch se aplicaron para conocer si existían diferencias estadísticas significativas en la media de la longitud y peso de juveniles, adultos, hembras y machos de pargos y en juveniles hembras, hembras y machos de meros. De acuerdo a las diferencias observadas, se procedió al cálculo de la relación L-P, parámetros a y b, error estándar (SE b) y coeficiente de determinación (R2) por separado (juveniles, adultos, hembras y machos) para cada especie. Los valores del parámetro b para todas las especies se encontraron dentro del rango esperado de 2.5 a 3.5 para pendientes de la relación L-P en peces. Los pargos tuvieron valores de b: juveniles de hembras de 2.44-2.77, juveniles de machos 2.16-2.94, hembras adultas 2.63-2.80 y machos adultos 2.63-2.98. Los meros tuvieron un valor de b para juveniles de hembras: 2.66-3.20, adultos hembras: 2.73-3.31 y adultos de machos: 2.93-3.29. Para cada relación, el valor de b fue probado a través de una prueba de t-Student para explorar diferencias significativas del coeficiente alométrico (b=3), lo cual indicaría cambios en la forma del cuerpo de los individuos. Finalmente pruebas de hipótesis sobre las diferencias entre pendientes obtenidas de las relaciones L-P mostraron distintas estanzas de crecimiento relacionadas en pargos con el desarrollo gonadal y en meros con el desarrollo gonadal pero también con el cambio de sexo. A través de este estudio se pudo observar la existencia de distintas estanzas de crecimiento en especies de alta importancia comercial para el Sur del Golfo de México. Por lo tanto se recomienda la obtención de las relaciones L-P por separado según el sexo y desarrollo gonadal de cada especie, para evitar una sobre estimación o un cálculo erróneo de la tasa de crecimiento poblacional la cual se utiliza en manejo de las pesquerías para determinar algunos puntos de referencia como el criterio de máximo rendimiento sostenible o bien el criterio de rendimiento por recluta.

The reproductive cycle of the oyster Crassostrea gasar / Ciclo reprodutivo da ostra Crassostrea gasar

The purpose of this study was to analyze the reproductive cycle of the oyster Crassostrea gasar (= C. brasiliana) in the field and the laboratory. The reproductive cycle of the animals was evaluated in the field at Sambaqui Beach, Florianópolis, SC (27° 29′18″ S and 48° 32′12″ W) from May 2008 through November 2009. In July, the animals were in the resting stage. The early growth stage began in August and was followed by the late growth stage in October. In November and December, the oysters began to enter the mature stage. Females in spawning condition were predominant during these months. The stages of the reproductive cycle were positively associated with temperature (r=0.77, P<0.01) and negatively associated with salinity (r=−0.56, P=0.042). These findings demonstrated that increased temperature and reduced salinity influence the reproductive development of Crassostrea gasar. The condition index (CI) of the animals was also associated with the seawater temperature. The highest values of the condition index were observed during the months when the temperature of the seawater was gradually increasing. A laboratory experiment was performed to test the effect of salinity on the reproductive cycle of the oysters. The experiment was conducted in standardized tanks. The animals were conditioned using two salinities (24‰ and 34‰). The salinity regime influenced the development of the gonadal tissue of the oysters. A salinity of 24‰ produced greater reproductive development.

O presente estudo teve como objetivo avaliar o ciclo reprodutivo da ostra Crassostrea gasar, em campo e em laboratório. O estádio de desenvolvimento do ciclo reprodutivo dos animais foi acompanhado na Praia do Sambaqui/Florianópolis/SC (27°29′18″S e 48°32′12″W) entre maio de 2008 e novembro de 2009. No mês de julho os animais encontravam-se no estádio de repouso e entre os meses de agosto a outubro, as ostras seguiram nos estádios de pré-maturação e maturação. Entre os meses de novembro e dezembro, as ostras começaram a ser encontradas no estádio maturo, havendo predominância de fêmeas aptas a eliminação de gametas. Houve associação positiva (r=0,77; P<0,01) entre o estádio de desenvolvimento do ciclo reprodutivo das ostras e a temperatura, bem como associação negativa com a salinidade (r=−0,56; P=0,042), demonstrando que tanto o aumento da temperatura como a redução da salinidade são fatores ambientais que influenciam no desenvolvimento reprodutivo das ostras dessa espécie. O índice de condição (IC) dos animais, também teve relação com a temperatura da água do mar, sendo os maiores índices observados nos meses em que a temperatura da água do mar teve aumento gradativo. Também foi realizado um experimento em laboratório visando testar o efeito da salinidade da água sobre o desenvolvimento reprodutivo das ostras. Para tanto, os animais foram condicionados em tanques padronizados e testaram-se duas salinidades (24‰ e 34‰). Observou-se que o regime de salinidade influenciou o desenvolvimento do tecido gonádico das ostras, sendo que a salinidade de 24‰ permitiu aos animais maior desenvolvimento reprodutivo.

Variación del ciclo gonádico del ostión americano, Crassostrea virginica (Ostreoida: Ostreidae) en función de su talla en la laguna de Tamiahua, Veracruz, México / Variation of gonadal cycle of the american oyster, Crassostrea virginica (Ostreoida: Ostreidae) as a function of height in Tamiahua Lagoon, Veracruz, Mexico

The American oyster, Crassostrea virginica is one of the most important fishery resources of the Gulf of Mexico, where it has been classified as “resource exploited at maximum”. Since 1994 state authorities set a minimum extraction shell length of 70 mm (adult size); this was based on population studies alone. We compare the gonadal cycle of subadults oysters with adult organisms. From January to December 2011, 90 oysters were collected monthly in Tamiahua Lagoon, Veracruz and classified as subadults (50-69mm; 75% of sample) and adults (≥70mm). Histological gonad sections were classified in four categories: rest, gametogenesis, maturation and release of gametes. In subadults, the rest stage had two peaks (January 22% and June 13%), and gametogenesis between January and July (22-74%). Maturation was observed in July, August and September (40, 64 and 41% respectively) and release in October (66%) and November (45%). Correspondingly, adults were resting in January and June (17 and 13%), and January-July gametogenesis (56-88%), matured in August and September (64 and 42%) and released gametes in September and October (54 and 70%). The gametogenic cycle was similar in subadults and adults: the species breeds from sizes equal or smaller than 50 mm and this should be considered by authorities. Rev. Biol. Trop. 62 (Suppl. 3): 201-206. Epub 2014 September 01.

El ostión americano (Crassostrea virginica) es uno de los recursos de pesca mas importantes en el Golfo de México, donde es clasificado como “recurso aprovechado al máximo”. Desde 1994 las autoridades estatales fijaron una talla mínima de extracción de 70mm de longitud de concha (tamaño adulto); esto basado en estudios aislados de poblaciones. Comparamos el ciclo gonadal de subadultos y adultos. De enero a diciembre de 2011, se colectaron 90 ostiones mensualmente en la laguna de Tamiahua, Veracruz y se clasificaron como subadultos (40-69 mm) y adultos (>70mm). Los cortes histológicos de las gónadas se clasificaron en cuatrocategorías: reposo, gametogénesis, maduración y liberación de gametos. En subadultos, la categoría de reposo tuvo dos picos (enero 22% y junio 13%) y la gametogénesis entre enero y julio (22-74%). La maduración se observó en julio, agosto y setiembre (40, 64 y 41%) y la liberación en octubre (66%) y noviembre (74%). Correspondientemente, los adultos reposaban en enero y junio (17 y 13%), y la gametogénesis entre enero y julio (56-88%), maduraban en agosto y setiembre (64 y 42%) y liberaban gametos en setiembre y octubre (54 y 70%). El ciclo gametogénico fue similar entre ostiones subadultos y adultos: la especie se reproduce con tamaños igual o inferior a 50mm y esto lo deben considerar las autoridades.

Reproducción del camarón rosado Farfantepenaeus notialis (Decapoda: Penaeidae) en el Caribe colombiano / Reproduction of the pink shrimp Farfantepenaeus notialis (Decapoda: Penaeidae) in the Colombian Caribbean

The shallow water pink shrimp (Farfantepenaeus notialis) is among the socioeconomically most important resources of the Caribbean. The lack of biological and fishery information is of great concern for the fisheries management authorities. The presented study therefore aimed at the investigation of the reproductive cycle, the size composition and the size at first maturity of this species as a basis for the ordination and management of this resource. The study was conducted from June 2012 to May 2013 off the coast of the Caribbean Sea of Colombia. A total of 5 356 individuals were collected, identified, classified and preserved for their subsequent analysis in the laboratory. Size, weight, sex and gonad stage were recorded for each specimen. Significant differences were found in sex ratio in all months sampled with a clear predominance of females. Mature females were found year-around, but two reproductive peaks were identified during the periods October-December and April-June. The mean catch total length size (MCS) for females and males was 148.00mm and 122.54mm, respectively. The mean size at maturity (LT50%) was 129.34mm for females and 97.77mm for males. MCS was always above LT50% for both sexes. Considering the large reduction in fishing effort in the Colombian Caribbean Sea over the last years, we could expect that the shrimp population is in a rebuilding process or perhaps it may be already restored.

El camarón de aguas someras, es uno de los recursos de mayor importancia socioeconómica en la región Caribe. La falta de información biológica pesquera, es una preocupación de los administradores pesqueros. Por tanto, el presente estudio tiene como objetivo conocer la época reproductiva, la estructura de tallas y la talla media de madurez del camarón de aguas someras (Farfantepenaeus notialis) como insumo para la ordenación y manejo pesquero en el Caribe colombiano. El estudio se llevó a cabo desde junio del 2012 hasta mayo del 2013 en el Caribe colombiano. Se recolectaron 5 356 individuos, los cuales fueron identificados, clasificados y conservados para su análisis en el laboratorio, donde se analizaron las muestras tomando datos de talla, peso, sexo y estadio gonadal. Se encontraron diferencias significativas en la razón de sexo durante todos los meses muestreados, con una mayor proporción de hembras. Se presentaron hembras maduras durante todo el año, pero con dos picos reproductivos de máximo desove, uno entre octubre y diciembre y el otro entre abril y junio. La talla media de captura (TMC) durante todo el muestreo para las hembras fue de 148.0mm de longitud total (LT) y para los machos fue de 122.5mm LT. La talla media de madurez (LT50%) para las hembras y machos fue de 129.34mm LT y 97.77mm LT, respectivamente. La TMC siempre fue mayor que la LT50% para ambos sexos. Debido a la gran disminución del esfuerzo pesquero en el Caribe colombiano durante los últimos 10 años, se espera que este recurso se encuentre en una fase de recuperación o ya esté recuperado.

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.

Reproduction of Blackfin tuna Thunnus atlanticus (Perciformes: Scombridae) in Saint Peter and Saint Paul Archipelago, Equatorial Atlantic, Brazil / Reproducción del atún de aleta negra Thunnus atlanticus (Perciformes: Scombridae) en el Archipiélago San Pedro y San Pablo, Atlántico Ecuatorial, Brasil

The reproduction of Blackfin tuna Thunnus atlanticus has been described for coastal regions, and for a long time, this species was considered to be a strictly continental spawner. Recently, this species was observed around a seamount habitat 500 nautical miles Northeast of Brazil, located between South America and Africa. In this study we describe the reproductive biology of Blackfin tuna at Saint Peter and Saint Paul Archipelago (SPSPA). Male and female gonads were sampled from December 2008 to July 2010, and analyzed macro and microscopically. A total of 361 fish were sampled (247 males and 114 females). Males were more common than females, with a sex ratio of 2.2 ♂:1♀. The fork length (FL) of all sampled specimens ranged from 38 to 98cm, and larger length classes were more frequent in males. It was possible to distinguish six maturity phases for females: immature, developing, spawning capable, actively spawning, regressing and recovering. Five phases were identified for males: immature, developing, spawning capable, actively spawning and recovering. The gonad index (GI) mean monthly values ranged from 6.6 (SD=4.1) to 58.4 (SD=34.7) for females, and from 2.6 (SD=1.3) to 66.2 (SD=30.4) for males. For both sexes, the largest GI values were observed at the beginning of the first semester of the year. Size at first maturity was estimated at 48cm FL and 55cm FL for females and males respectively. Approximately 80% of the specimens were adults and considered to be in reproductive conditions. Histological analysis of the ovaries and testes showed that most of the specimens were sexually mature and were reproductively active during all months of the year. However, females with mature ovaries, with large amounts of hydrated oocytes and post-ovulatory follicles, were mainly found from December to March, thus these months may constitute the main spawning season in SPSPA. Batch fecundity varied between 272 025 and 1 140 584 oocytes for 56 and 68cm FL females respectively. Oocyte development and spawning patterns suggest a multiple spawning behavior. The results revealed that Blackfin tuna is using the SPSPA as a spawning ground, similar to other species commonly observed in the same area during the same reproductive season.

A pesar de la importancia de las capturas del atún de aleta negra Thunnus atlanticus en el noreste de Brasil y en las cercanías del Archipiélago San Pedro y San Pablo (ASPSP), hay una escasez de información sobre su reproducción, especialmente en las islas. La reproducción del atún de aleta negra en este archipiélago se estudió de diciembre 2008 a julio 2010. Con este fin, se recolectaron 361 gónadas de hembras y machos, los machos fueron predominantemente más frecuentes en la muestra total, con una proporción sexual de 1♀:2.2 ♂. La longitud furcal todos los ejemplares muestreados varió entre 38 y 98 cm, y los machos fueron más abundantes en las clases de mayor longitud. Los valores medios mensuales del índice gonadal (IG) variaron de 6.6 (SD=4.1) a 58.4 (SD=34.7) y de 2.6 (SD=1.3) a 66.2 (SD=30.4) para hembras y machos, respectivamente. Los mayores valores de IG para ambos sexos fueron observados el inicio del primer semestre. Los análisis histológicos mostraron que la mayoría de los ovarios y testículos correspondieron a especímenes aptos para reproducirse. Sin embargo, hembras con ovarios maduros, con gran cantidad de oócitos hidratados y folículos post ovulatorios, se encontraron principalmente de diciembre a marzo, que se considera es la época de reproducción del atún de aleta negra alrededor del ASPSP.

Fecundity, reproductive seasonality and maturation size of Callinectes sapidus females (Decapoda: Portunidae) in the Southeast coast of Brazil

C. sapidus fisheries has a significant influence on the economy of some countries in North America and has a relative extensive literature in these regions. However, only few papers discuss the ecology of C. sapidus in the South Atlantic, despite its economic importance in that region. We studied the fecundity, reproductive seasonality and maturation size of C. sapidus females captured in the Southeast coast of Brazil from January to December 2002. Females were separated, weighted (Wt), and cephalothorax width (CW) was measured. Furthermore, the eggs-masses were classified according to embryonic development, separated, weighted (We) and fixed. Eggs were also separated and counted, resulting in the average number of eggs per individual (Ne). A total sample of 307 females was collected: 78 young, 130 adults and 99 ovigerous. Ovigerous females showed CW between 7.49 and 15.89cm with average of 12.21cm and were distributed throughout the sample period, with highest incidence between December and March. The onset of morphological maturity (L50) occurred at CW=10.33cm, and the size in which all were mature (L100) was CW=11.20cm. Individual fecundity ranged from 689 356 to 3 438 122 with an average of 2 006 974. The CW showed a positive growth trend with Ne and We. We concluded that in order to ensure the resource sustainability, it is necessary to prohibit captures of C. sapidus in these regions, especially during summer. Additionally, our studies suggest that the minimum capture size should be 11cm of carapace width.

Hay pocos estudios sobre la ecología de C. sapidus en el Atlántico Sur, a pesar de su importancia económica en la región. El presente estudio tiene como objetivo conocer la fecundidad, periodo reproductivo y talla de primera madurez morfológica de las hembras de C. sapidus, con el fin de contribuir a una mejor comprensión de la especie en el Atlántico occidental, así como ayudar en la toma de medidas de gestión en la región. Las muestras fueron recolectadas mensualmente de enero a diciembre 2002 en sudeste del Brazil. Se recogieron 307 hembras: 78 jóvenes, 130 adultos y 99 ovígeras. Las hembras ovígeras mostró su intervalo de talla de 7.49-15.89cm ancho del carapazón (AC) y se distribuyeron en todo el período de la muestra, con mayor incidencia entre diciembre y marzo. El inicio de la madurez morfológica (L50) fue con la AC=10.33cm y el tamaño que tenían todos los maduros (L100) con AC de 11.20cm. Fecundidad individual osciló entre 689 356 a 3 438 122, con una media 2 006 974. El AC mostró una tendencia positiva en el crecimiento con número de huevos y el peso del huevos. El conocimiento de los aspectos reproductivos de la población es importante en la definición de medidas de gestión para el uso sostenible con el fin de renovar y continuar con la misma.

Biología reproductiva de Lutjanus guttatus (Perciformes: Lutjanidae) en el Parque Nacional Natural Utría, Pacífico colombiano / Reproductive biology of Lutjanus guttatus (Perciformes: Lutjanidae) in Utría National Park, Colombian Pacific

Protected areas are important for natural population conservation since they work as refuge, feeding and breeding areas, where specimens should be exempt from human pressure. The generation of better criteria for management decisions and conservation of fishery resources, is based on the reproductive aspects of species that support fishing activities, since this information is related to the abundance, size and frequency of capture. With this aim, the reproductive biology of the spotted snapper Lutjanus guttatus was studied from April 2008 and February 2009 at the Utría National Park, Colombian Pacific. For this, we analyzed the volume of catch, size structure, sex ratio, fecundity, maturity size, breeding areas and seasons (n=278), of daily landings of 21 units of artisanal fisheries in ten fishing grounds in the Park. Form all landings, we evaluated a total of 4 319 individuals belonging to 84 species. Based on the number of individuals, Lutjanus guttatus ranked third in catches representing 6.4% (278 individuals), and 16th with 1.8% (95.79kg), based on catch biomass. The average weight was 0.34kg ±0.25kg, while 29cm±6.4cm for total length. The total length-weight relationship had the best fit (Kruskal-Wallis, p<0.05, n=272) with the equation PT=0.00000885* L T3.09. The occurrence of mature fish and high condition factors suggested a spawning season in June, September and October in sandy and rocky shores. This species showed an asynchronical gonadal development, with a mean sexual maturity size estimated in 23.5cm total length, and an absolute fecundity of 156 253.11 oocytes (mode of 4µm diameter). We concluded that L. guttatus medium sizes observed indicated a fishing pressure on small size specimens (the minimum size being 18cm); thus, we recommend the implementation of minimum catch sizes based on the criterion of size at maturity LT100 (25.5cm) and to apply seasonal fishing closures during the highest reproductive activity (June- October). However, it is necessary to obtain additional biological information with multi-year monitoring to improve fisheries management criteria in the area.

Las áreas protegidas son importantes para la conservación de las poblaciones naturales ya que funcionan como zonas de refugio, alimentación y reproducción en la que los organismos deberían estar eximidos de la presión antrópica, pero en aquellas áreas donde se permite la pesca, es elemental conocer los aspectos reproductivos de las especies que soportan la presión pesquera, ya que ésta información relacionada con las abundancias, tallas y frecuencias de captura pueden ofrecer mejores criterios para tomar decisiones de manejo y conservación de los recursos pequeros. La biología reproductiva del pargo lunarejo Lutjanus guttatus se estudió entre abril 2008 y febrero 2009 en el Parque Nacional Utría, Pacífico colombiano. Se analizaron los volúmenes de captura, estructura por tallas, proporción de sexos, fecundidad, talla media de madurez, áreas y épocas de reproducción (n=278). La longitud total osciló entre 18 y 56cm con una media y desviación estándar de 29±6.4cm. La talla media de madurez fue estimada en 23.5cm de longitud total, la fecundidad absoluta fue 156 253.11 ovocitos, con una moda de 4μm de diámetro y un desarrollo gonadal asincrónico. La presencia de individuos maduros y de un alto factor de condición sugieren épocas de desove en junio, septiembre y octubre en litorales rocosos y arenosos.

Gonad maturation of Haemulon plumieri (Teleostei: Haemulidae) in Ceará state, Northeastern Brazil / Maturação gonadal de Haemulon plumieri (Teleostei: Haemulidae) no Nordeste do Brasil

To elucidate the reproductive cycle of any animal, it is first necessary to understand the development of the germ cells and how this process occurs throughout the reproductive tract. Thus, the aim of the present study was to understand the oogenesis and spermatogenesis, as well as the ovarian and testis maturation and type of spawning, of Haemulon plumieri. A total of 119 females and 136 males were analysed. Based on micro and macroscopic characteristics of gonads, the following stages of maturation for females were determined: immature, maturing, ripe, partially spawning, spawning and resting. For males, only the stages immature, maturing, ripe and spent were observed. We can conclude that the ovarian development occurs cyclically, in which the female can spawn more than two times during the reproductive season with the spawning “synchronous in more than two groups”. Since males do not present the “rest” stage after copulation, the maturation process is continuous.

Para se conhecer a biologia reprodutiva de qualquer animal, é fundamental o conhecimento prévio do desenvolvimento das células germinativas e como esse processo ocorre ao longo do trato reprodutivo. Desta forma, o objetivo do presente trabalho foi descrever a oogênese e a espermatogênese, bem como o desenvolvimento maturacional dos ovários e testículos, e o tipo de desova do Haemulon plumieri. Foram analisadas 119 fêmeas e 136 machos. A partir das características macro e microscópicas das gônadas, foram estabelecidos os seguintes estágios de maturação para fêmeas: imatura, em maturação, matura, parcialmente desovada, desovada e em repouso. Para os machos, foram identificados apenas os seguintes estágios: imaturo, em maturação, maturo e esvaziado. A partir das análises, pôde-se concluir que o desenvolvimento ovariano é cíclico, em que a fêmea pode desovar mais de duas vezes por estação, por apresentar a desova do tipo ‘sincrônica em mais de dois grupos'. Uma vez que os machos não apresentam o estágio ‘em repouso' após a cópula, o processo de maturação é contínuo.

Reproductive cycle and embryonic development of the gastropod Melampus coffeus (Linnaeus, 1758) (Ellobiidae) in the Brazilian Northeast / Ciclo reprodutivo e desenvolvimento embrionário do gastrópode Melampus coffeus (Linnaeus, 1758) (Ellobiidae) no Nordeste do Brasil

Melampus coffeus belongs to a primitive group of pulmonate mollusks found mainly in the upper levels of the marine intertidal zone. They are common in the neotropical mangroves. Little is known about the biology of this species, particularly about its reproduction. The aim of this study was to 1) characterize the morphology and histology of M. coffeus' gonad; 2) describe the main gametogenesis events and link them to a range of maturity stages; 3) chronologically evaluate the frequency of the different maturity stages and their relation to environmental factors such as water, air and sediment temperatures, relative humidity, salinity and rainfall; and 4) characterize M. coffeus' spawning, eggs and newly hatched veliger larvae. Samples were collected monthly between February, 2007 and January, 2009 from the mangroves of Praia de Arpoeiras, Acaraú County, State of Ceará, northeastern Brazil. The characterization of the gonad development stages was carried out using routine histological techniques. The results of this study show that Melampus coffeus is a simultaneous hermaphrodite. The follicles have masculine and feminine elements, interleaved within the gonad. M. coffeus presents a well-defined synchronous reproductive cycle, showing successive maturation, release and resting periods. The average diameter of the oocytes was negatively correlated with salinity and positively correlated with rainfall. The results show that no reproductive activity occurs during periods of drought. After the dry season, the increasing rainfall levels and reduced salinity lead to the appearance of very dense populations, predominantly composed of small individuals.

Melampus coffeus encontra-se em um grupo primitivo de moluscos pulmonados, primordialmente marinhos, habitantes dos níveis superiores da zona entremarés, comum em manguezais do Oceano Atlântico. Pouco se sabe sobre a biologia da espécie, em especial, sobre a sua reprodução. Os objetivos deste trabalho foram: 1) caracterizar morfo-histologicamente a gônada de M. coffeus; 2) descrever os principais eventos da gametogênese e associá-los a uma escala de estágios de maturidade; 3) avaliar temporalmente a frequência dos estágios de maturidade e sua possível relação com os fatores ambientais, como a temperatura da água, do ar e do sedimento, a umidade relativa, a salinidade e a pluviosidade, e 4) caracterizar a postura, os ovos e a véliger recém-eclodida de M. coffeus. Foram realizadas coletas mensais de fevereiro de 2007 a janeiro de 2009, no manguezal da Praia de Arpoeiras, município de Acaraú-Ceará, na Região Nordeste do Brasil. A caracterização das fases de desenvolvimento da gônada foi realizada utilizando-se técnicas histológicas de rotina. Os resultados deste estudo mostram que Melampus coffeus é um hermafrodita simultâneo. Os folículos apresentam elementos masculinos e femininos, distribuindo-se na gônada intercalados radialmente. M. coffeus apresenta um ciclo reprodutivo sincrônico bem definido, evidenciando-se períodos sucessivos de amadurecimento, de liberação e de repouso. O diâmetro médio dos oócitos apresentou correlação negativa com a salinidade e positiva com a pluviosidade. Os resultados indicam que, nos períodos de estiagem, não há atividade reprodutiva. Após essa estação, quando os valores de pluviosidade aumentam e a salinidade diminui, as populações são bastante densas e predominam indivíduos pequenos.