ABSTRACT Fresh roes of rock-boring urchin sea Echinometra lucunter lucunter has a high food value, which enhances its fishery and mariculture; however, biochemical composition and development are influenced by environmental conditions. To evaluate protein, lipid, and carbohydrate content, and be able to establish how it varies the storage in the gonads during upwelling (high primary productivity/22-24°C) and stratification (low primary productivity/28-30°C) seasons, adult sea-urchins (> 30 mm) were monthly collected from Lobos Islet (Venezuela). Salinity, temperature, dissolved oxygen, transparency, total seston and chlorophyll a in superficial seawater were averaged. Biometric parameters, sex, reproductive stage, gonadosomatic index (GI), and biomolecule content in the gonads were determined per individual. Gonadal development of E. lucunter lucunter occurs during the upwelling-stratification transition, corresponding with the seawater temperature increase. Biomolecules showed temporal variations associated with gonadal production; a negative relationship existed between the preferential use of carbohydrates and lipids. Maximal gonad production and accumulated carbohydrate and protein were reached during stratification; however, during upwelling synchronized spawns were observed as well as a respective decrease in lipids and carbohydrates. The environmental conditions during stratification stimulate the gonadal development of E. lucunter lucunter, in comparison the coastal upwelling acts as a trigger of synchronized spawning for both sexes. The energy biomolecules are stored in the roes mainly during stratification, using with preference to carbohydrates to metabolic demand.

RESUMEN Las huevas frescas del erizo de mar Echinometra lucunter lucunter presentan un alto valor alimenticio, lo cual potencia su pesquería y maricultura; no obstante, su composición bioquímica y desarrollo están influenciadas por las condiciones ambientales. Para evaluar el contenido de proteínas, carbohidratos y lípidos, y poder establecer cómo varía el almacenamiento en las gónadas durante las temporadas de surgencia (alta productividad primaria/22-24°C) y estratificación (baja productividad primaria/28-30°C), erizos de mar adultos (> 30 mm) fueron recolectados mensualmente en el Islote Lobos (Venezuela). La salinidad, temperatura, oxígeno disuelto, transparencia, seston total y clorofila a en aguas superficiales fueron estimadas. A cada individuo se le determinó su biometría, sexo, estadio reproductivo, índice gonadosomático (IGS) y contenido de biomoléculas en las gónadas. El desarrollo gonadal de E. lucunter lucunter se inicia durante la transición de surgencia a estratificación, coincidiendo con los aumentos en la temperatura del agua. Las biomoléculas mostraron variaciones temporales asociadas con la producción de gónadas; existiendo una relación negativa entre la preferencia de uso de carbohidratos y lípidos. La maduración gonadal máxima y acumulación de carbohidratos y proteínas fueron alcanzadas durante la estratificación; sin embargo, durante la surgencia se observaron desoves sincronizados, así como un descenso en los lípidos y carbohidratos. Las condiciones ambientales durante la estratificación estimulan el desarrollo gonadal de E. lucunter lucunter, en contraste, la surgencia costera actúa como detonante de los desoves de manera sincronizada para ambos sexos. El almacenamiento de biomoléculas energéticas ocurre principalmente durante la estratificación, usando preferiblemente los carbohidratos para suplir la demanda metabólica.

Resumo Aspectos da biologia reprodutiva de Donax striatus foram estudados. Os indivíduos foram coletados mensalmente de fevereiro de 2021 a janeiro de 2022 na praia Gado Bravo, no município de Tibau do Norte, estado do Rio Grande do Norte, Brasil. Donax striatus é uma espécie dióica sem dimorfismo macroscópico externo (na concha) ou interno (gônadas). Assim, é necessário um exame microscópico das células reprodutivas. Para a caracterização dos estágios de desenvolvimento gonadal e determinação do tamanho na primeira maturidade sexual (L50), 30 espécimes foram selecionados mensalmente entre fevereiro de 2021 e janeiro de 2022 e submetidos ao processamento histológico. O índice de Condição (IC) de cada indivíduo foi estimado e as variações mensais foram estatisticamente avaliadas. O tamanho de primeira maturação (L50) foi estimado em 14,2 mm de comprimento de concha. Para promover a conservação da espécie, recomenda-se a captura de indivíduos maiores que 14,2 mm. Os menores índices de condição foram encontrados na estação seca, com maior ocorrência de organismos em fase de eliminação e exibindo reorganização do tecido gonadal. Índices maiores foram encontrados no período chuvoso, com presença de indivíduos maduros. A natureza contínua da gametogênese em Donax stritatus reflete a influência das chuvas na região. Machos e fêmeas apresentam pico de eliminação de gametas com pausas durante o ano, mas com presença de indivíduos em maturação e eliminação ao longo do ano. Como a mariscagem visando Donax striatus é excessiva na Praia de Gado Bravo, no estado do Rio Grande do Norte, espera-se que os resultados do presente estudo possam contribuir para o estabelecimento de medidas de manejo da atividade e estratégias de conservação da espécie. estudados 202 Bravo Norte Brasil concha gônadas. gônadas . (gônadas) Assim reprodutivas L50, L50 L , 3 histológico IC (IC avaliadas (L50 142 14 2 14, recomendase recomenda se seca chuvoso maduros região ano esperase espera 20 (gônadas L5 (L5 1 (L

Abstract Aspects of the reproductive biology of Donax striatus were studied from individuals collected from Gado Bravo Beach in the municipality of Tibau do Norte, state of Rio Grande do Norte, Brazil. Donax striatus is a dioic species without external (on the shell) or internal (gonads) macroscopic dimorphism. Thus, a microscopic examination of the reproductive cells is necessary. For the characterization of the gonadal development stages and determination of the size at first sexual maturity (L50), 30 specimens were selected monthly between February 2021 and January 2022 and submitted to histological processing. The condition index (CI) of each individual was estimated and monthly variations were statistically assessed. The size at first maturity (L50) was estimated to be 14.2 mm in shell length. To foster conservation of the species, catches of individuals larger than 14.2 mm is recommended. The lowest condition indices were found in the dry season, with a greater occurrence of organisms in the elimination stage and exhibiting gonad tissue reorganization. Higher indices were found in the rainy season, with the presence of mature individuals. The continuous nature of gametogenesis in Donax stritatus reflects the influence of rainfall in the region. Males and females have peak gamete elimination with pauses during the year, but with the presence of maturing and eliminating individuals throughout the year. As shellfish gathering targeting Donax striatus is excessive on Gado Bravo Beach in the state of Rio Grande do Norte, it is hoped that the results of the present study can contribute to the establishment of management measures for the activity and conservation strategies for the species. Norte Brazil gonads (gonads dimorphism Thus necessary L50, L50 L , 3 202 processing CI (CI assessed (L50 142 14 2 14. length recommended season reorganization region year L5 20 (L5 1 (L

Resumo O polvo com chifres Eledone cirrhosa, uma espécie de tamanho médio encontrada no Golfo Arábico ao largo da Arábia Saudita, foi coletado mensalmente no Golfo Arábico ao largo da cidade de Dammam durante o período de janeiro a dezembro de 2022. As amostras foram dissecadas e preparadas para exame por microscopia eletrônica. Durante a maturação genital, os túbulos seminíferos se estabelecem nos testículos, com espermatogônias ativas se dividindo. Espermatócitos 1 são observados no túbulo, seguidos de aumento de espermatogônias e espermatócitos em agosto. A espermiogênese começa com espermátides esféricas evoluindo para espermátides alongadas. Em setembro, as espermatogônias ativas, as divisões meióticas e o aumento da espermiogênese continuam. Os espermatozoides aparecem na Bolsa de Needham, indicando maturidade sexual. O ovário passa por vários estágios de desenvolvimento, com oócitos no estágio I em junho e julho, seguido pelo estágio II em outubro e novembro. No estágio IIIc, os cordões foliculares invadem o citoplasma do oócito, formando numerosas inclusões lipídicas e grânulos proteicos. O citoplasma contém cisternas de retículo endoplasmático e um Aparelho de Golgi pouco desenvolvido. O estágio IV ocorre em novembro, caracterizado pelo máximo desenvolvimento dos cordões foliculares e pelo início da vitelogênese. O ooplasma contém numerosas inclusões lipídicas, um sincício e células secretoras. A partir de dezembro, os oócitos do estágio V estão principalmente presentes, indicando a fase de atividade de secreção máxima. As plaquetas da gema acumulam-se no ooplasma do ovócito e o córion se forma na zona pelúcida. Em janeiro, os primeiros óvulos lisos são encontrados no ovário de alguns polvos e sua proporção aumenta continuamente. Este estudo teve como objetivo investigar a ação mitogênica da gonadotrofina bem como identificar os períodos de intensa multiplicação celular durante o ciclo sexual por meio de métodos citológicos. cirrhosa Saudita 2022 eletrônica genital testículos dividindo túbulo agosto alongadas setembro continuam Needham julho novembro IIIc oócito proteicos desenvolvido vitelogênese secretoras presentes máxima acumulamse acumulam pelúcida continuamente citológicos 202 20 2

Abstract The horned octopod Eledone cirrhosa, a medium-sized species found in Arabian Gulf off Saudi Arabia, was collected monthly from the Arabian Gulf off Dammam city during January to December 2022. Samples were dissected and prepared for examination using transmission electron microscopy. During genital maturation, seminiferous tubules are established in the testis, with active spermatogonia dividing. Spermatocytes 1 are observed in the tubule, followed by an increase in spermatogonia and spermatocytes in August. Spermiogenesis begins, with spherical spermatids evolving into elongated spermatids. In September, active spermatogonia, meiotic divisions, and increased spermiogenesis continue. Spermatozoa appear in Needham's pouch, indicating sexual maturity. The ovary undergoes various stages of development, with oocytes at stage I in June and July, followed by stage II in October and November. In stage III, follicular cords invade the oocyte's cytoplasm, forming numerous lipid inclusions and protein granules. The cytoplasm contains cisternae of endoplasmic reticulum and a poorly developed Golgi apparatus. Stage IV occurs in November, characterized by the maximum development of follicular cords and the beginning of vitellogenesis. The ooplasm contains numerous lipid inclusions, a syncytium, and secretory cells. From December, stage V oocytes are mainly present, indicating the activity phase of maximum secretion. Yolk platelets accumulate in the oocyte ooplasm, and chorion forms at the zona pellucida. In January, the first smooth eggs are found in some octopuses' ovary, with their proportion increasing steadily. This study aimed to investigate the mitogenic action of gonadotropin and identify the periods of intense cell multiplication during the sexual cycle using cytological methods. cirrhosa mediumsized medium sized Arabia 2022 microscopy maturation testis dividing tubule August begins September divisions continue Needhams Needham s pouch maturity July November III granules apparatus vitellogenesis syncytium cells present secretion pellucida octopuses steadily methods 202 20 2

Abstract The female reproductive function is coordinated by the endocrine system driven by the hypothalamic-pituitary-gonadal (HPG) axis. While not directly part of the female reproductive system, the gut microbiome plays a crucial role in overall health, including reproductive health. The gut microbiome communicates bidirectionally with the brain via the gut-brain axis, influencing stress levels, mood, and hormonal balance, which can impact reproductive health and fertility. In addition to that, the vaginal and uterine microbiome are directly involved with the reproductive success of farm animals, including female fertility and offspring development. In this paper, we summarize some of the effects of bacterial contamination in the female reproductive tract and their association with reproductive performance in farm animals. hypothalamicpituitarygonadal hypothalamic pituitary gonadal HPG (HPG axis gutbrain levels mood balance that animals development paper

Abstract This study analyses body condition and digestive/metabolic parameters of Odontesthesargentinensis from Mar Chiquita Coastal Lagoon (MChCL) during different ovary maturity phases (II: developing; III: spawning capable; IIIas: actively spawning subphase). Silverside individuals in phases II and III maintained their body condition, while it improved in actively spawning subphase. Total weight and Fulton’s condition factor increase in 70% and 50%, respectively. No changes were observed during the ovary maturation phases in hepatosomatic index and intestinal coefficient. Maltase activity in the intestine remained unchanged, while Aminopeptidase-N was higher, about 300%, in the spawning capable phase (III). Alkaline phosphatase in the intestine was unchanged pointing out the maintenance of intestinal homeostasis. Liver glycogen concentration decreased, about 40%, in the actively spawning subphase (IIIas), while muscle glycogen abruptly decreased in phase III and recovered in subphase IIIas. In intestinal fat, triglycerides concentration was lower 70% in subphase IIIas, while no changes occurred in liver and muscle. Muscle protein concentration decreased about 50% in actively spawning subphase. The findings shed light on the remarkable adaptability of this population of O. argentinensis from MChCL to support its gonadal maturation and active spawning maintaining and even improving its physical condition. digestivemetabolic digestive metabolic (MChCL (II developing IIIas . subphase) Fultons Fulton s 70 50 respectively coefficient AminopeptidaseN Aminopeptidase N higher 300 300% III. (III) homeostasis 40 40% , (IIIas) fat O 7 5 30 (III 4 (IIIas 3

Resumen Este trabajo analiza los parámetros digestivo/metabólicos y de condición corporal de Odontesthes argentinensis de la Laguna Costera Mar Chiquita (LCMCh) en diferentes fases de madurez ovárica (II: maduración; III: capacidad de desove; IIIas: subfase activo desovante). Pejerreyes en fases II y III mantuvieron su condición corporal, mientras que la misma mejoró en la subfase activo desovante. El peso total y el factor de condición de Fulton aumentaron en un 50% y 70% respectivamente. No se observaron cambios en el índice hepatosomático ni en el coeficiente intestinal en las diferentes fases de maduración ovárica. La actividad de maltasa en el intestino no varió, mientras que la actividad de N-aminopeptidasa fue 300% mayor en la fase con capacidad de desove (III). La actividad de fosfatasa alcalina en intestino no cambió, indicando el mantenimiento de la homeostasis intestinal. La concentración de glucógeno en hígado disminuyó un 40% en la subfase activo desovante (IIIas), mientras que el glucógeno en músculo disminuyó abruptamente en la fase III y se recuperó en la subfase IIIas. En grasa intestinal, la concentración de triglicéridos fue 70% menor en la subfase IIIas mientras que no hubo cambios en hígado y músculo. La concentración de proteínas en músculo disminuyó un 50% en la subfase activo desovante. Estos resultados destacan la capacidad de adaptación de esta población de O. argentinensis de la LCMCh para sostener la maduración gonadal y el desove manteniendo e incluso mejorando la condición corporal. digestivometabólicos digestivo metabólicos (LCMCh (II . desovante) 50 70 respectivamente varió Naminopeptidasa N aminopeptidasa 300 III. (III) cambió 40 IIIas, , (IIIas) O 5 7 30 (III 4 (IIIas 3

Abstract This review elucidates the physiological and endocrinological processes intrinsic to puberty and ovulation induction protocols in Bos indicus and Bos taurus beef heifers. Puberty is a complex physiological event involving gonadotropic and metabolic changes that lead to sexual maturity, first ovulation, and regular reproductive cycles, enabling females to reproduce. Exposure to progesterone-based hormonal protocols, with or without additional hormones, can reduce the age at first ovulation and improve sexual maturity through stimuli in the hypothalamus-pituitary-gonadal (HPG) axis and uterine development. However, inducing puberty differs from inducing ovulation, as it does not ensure the heifer will continue cycling or be ready to establish and maintain pregnancy after hormonal exposure. Regardless of the pharmacological basis, studies consistently report that beef heifers that had a corpus luteum (CL) prior to the timed-artificial insemination (TAI) protocol, have greater expression of estrus in response to synchronization and greater pregnancy per AI compared to heifers without a CL. The combination of P4 and E2 significantly impacts uterine development, increasing reproductive efficiency. Exposure to P4 causes a positive effect on inducing ovulation. However, studies indicate that the addition of E2 esters at the time of P4 device removal increases the ovulation rate. In general, the studies showed that fertility varied according to the type of the ovulation induction protocol used, but with inconsistent results. Although ovulation induction protocols are strategic tools to accelerate sexual maturity, a holistic view of the entire system is extremely important, combining integration with genetics and nutrition to enhance the reproductive outcomes of beef heifers. Future research is needed to understand and refine these protocols, driving the efficiency of beef cattle production systems. cycles reproduce progesteronebased progesterone based hormones hypothalamuspituitarygonadal hypothalamus pituitary gonadal HPG (HPG development However exposure basis CL (CL timedartificial timed artificial TAI (TAI P E rate general used results important systems

RESUMEN En el estado de Nayarit, al suroriente del Golfo de California, la pesca representa un porcentaje considerable en cuanto a fuente de ingresos para la población. La pesquería de corvinas es de gran importancia, sin embargo, no existe información biológica pesquera sobre estas en la región. Debido a su importancia, se describió la biología reproductiva de la corvina rayada Cynoscion reticulatus durante el año 2019. Se recolectaron muestras mensuales provenientes de desembarcos pesqueros para un total de 390 organismos. Se estimaron índices morfofisiológicos y se realizó un análisis histológico de las gónadas. Se observó una proporción sexual mayor en hembras (1:0,5) H: M. Se describió el desarrollo gonadal y el ciclo reproductivo. De acuerdo a los índices y el análisis histológico, se determinó que la corvina presenta un amplio periodo reproductivo entre los meses de abril a agosto. La temperatura superficial del mar y fotoperiodo presentaron una correlación positiva con la reproducción. En cuanto a la talla de madurez, se encontraron tallas muy similares para ambos sexos, para las hembras de 24,5 cm y de 23,6 cm de longitud estándar para los machos.

ABSTRACT In the state of Nayarit, in the southeastern Gulf of California, fishing represents a considerable percentage in terms of source of income for the population. The croaker fishery is of great importance; however, there is no biological-fishing information on them in the region. Due to its importance, the reproductive biology of the striped croaker Cynoscion reticulatus was described during 2019. Monthly samples from fish landings were collected for a total of 390 organisms. Morphophysiological indices were estimated and a histological analysis of the gonads was performed. A higher sex ratio was observed in females (1: 0.5) H: M. The gonadal development and the reproductive cycle were described. According to the indices and histological analysis, it was determined that the striped croaker has a wide reproductive period between April to August. Sea superficial temperature and photoperiod showed a positive correlation with reproduction. Regarding the size at first maturity, very similar sizes were found for both sexes, 24.5 cm for females and 23.6 cm of standard length for males.

Resumen Introducción: La Pácora (Plagioscion magdalenae) es una especie nativa de Colombia y en categoría de casi amenazada a nivel del país, de la que poco se conoce acerca de las estructuras con aporte etológico en su historia de vida. Objetivo: Analizar el desarrollo gonadal relacionado con la espermatogénesis de P. magdalenae y las implicaciones taxonómicas a partir de la vejiga natatoria. Métodos: Realizamos siete muestreos en dos periodos climáticos: el primero en octubre de 2019 a febrero de 2020 de recolectas bimensuales y la segunda de octubre 2020 a enero 2021 de recolectas mensuales; con el fin de abarcar cada momento del pulso de inundación de la cuenca baja del Magdalena. Describimos la histomorfología testicular y las características macroscópicas de la vejiga natatoria de la especie. Además, analizamos aspectos como relaciones morfométricas, clases de tallas por sexos, la proporción sexual y la época de madurez sexual. Resultados: Analizamos 142 ejemplares y 4 intervalos de tallas fueron establecidos (entre 145 y 575 mm LE), 66 fueron machos y 73 hembras con una proporción sexual global 1.1:0.9 (hembra-macho) sin diferencias. Los machos tienen testículos de tipo tubular, protegidos por el peritoneo que se encuentra recubierto por la musculatura sónica de la vejiga natatoria, la cual posee forma de ''zanahoria'' sin apéndices, con dos bandas laterales de músculos intrínsecos (promedio entre 6.75 cm de largo y 1.48 cm de ancho) unidos por una aponeurosis y que solo se encuentran en machos sexualmente maduros. Conclusión: Los testículos poseen una organización de tipo lobular irrestricto y la espermatogénesis se da en lóbulos seminíferos. La vejiga natatoria de la Pácora es simple y no tiene estructuras accesorias. La distribución geográfica de P. magdalenae se restringe a la cuenca del río Magdalena en Colombia.

Abstract Introduction: The Pácora (Plagioscion magdalenae) is a species native to Colombia and in near-threatened category at the country level, of which little is known about the structures with ethological contribution in its life history. Objective: To analyze the gonadal development related to spermatogenesis of P. magdalenae and the taxonomic implications from the swim bladder. Methods: We collected seven samples in two climatic periods: the first from October 2019 to February 2020 of bimonthly collections, and the second from October 2020 to January 2021 of monthly collections; to cover every moment of the flood pulse of the lower Magdalena basin. We described the testicular histomorphology and macroscopic characteristics of the swim bladder of the species. In addition, we analyzed aspects such as morphometric relationships, size classes by sex, sex ratio and time of sexual maturity. Results: We analyzed 142 specimens and established 4 size intervals (between 145 and 575 mm SL), 66 were males and 73 females with an overall sex ratio of 1.1:0.9 (female-male) with no differences. Males have tubular testes protected by the peritoneum covered by the sonic musculature of the swim bladder, which has a ''carrot'' shape without appendages, with two lateral bands of intrinsic muscles (average between 6.75 cm long and 1.48 cm wide) connected by an aponeurosis and found only in sexually mature males. Conclusion: The testes have an unrestricted lobular organization and spermatogenesis occurs in the seminiferous lobes. The swim bladder of the Pácora is simple and has no accessory structures. The geographic distribution of P. magdalenae is restricted to the Magdalena River basin in Colombia.

Resumen El desarrollo tecnológico para el cultivo de Gymnotus sp. es relevante porque este género tiene un impacto socioeconómico en regiones sudamericanas donde la pesca deportiva es una actividad importante. Aunque Gymnotus sp. se reproduce en cautiverio, la supervivencia de los alevines en los estanques puede ser insuficiente para un sistema de cultivo. El objetivo de este trabajo fue evaluar la respuesta de diferentes parámetros reproductivos a la inducción hormonal en Gymnotus sp. con extracto bruto de hipófisis de carpa (EBH) y hormona liberadora de gonadotrofinas (GnRH). Las muestras de gametos del tratamiento con EBH se extrajeron 12 y 20 horas después de la dosis desencadenante, las muestras del tratamiento con GnRH se extrajeron 10 y 12 horas después de la aplicación hormonal. El porcentaje de ovocitos con vesícula germinal periférica (%OVGP) y el diámetro de los ovocitos mostraron diferencias significativas entre grupos tratados con EBH con un intervalo captura-inducción (IC-I) de corta duración, con reproductores en etapas avanzadas de desarrollo gonadal. Se pudieron extraer ovocitos con éxito a dos hembras inducidas con EBH, 12 horas después de la dosis desencadenante y, además, se extrajo semen sólo de los machos inducidos con EBH. La estimulación con GnRH no dio resultados positivos en las diferentes dosis e IC-I utilizados, dado que no se pudieron extraer gametos. Este trabajo es la primera descripción de los parámetros de calidad del semen en Gymnotus sp. Futuras líneas de trabajo deberán centrarse en el manejo de variables ambientales para establecer una estrategia de reproducción que se pueda utilizar a nivel productivo.

Abstract. Technological development for Gymnotus sp. farming is relevant because this species has a socio- economic impact in South American regions where sport fishing is an important activity. Although Gymnotus sp. breeds in captivity, fry survival in ponds can be unacceptable for culture systems. The objective of this work was to test the response to hormonal induction of Gymnotus sp. with carp pituitary extract (CPE) and gonadotrophin-releasing hormone (GnRH) in relation to different male and female reproductive parameters. CPE treatment specimens were stripped 12 and 20 hours after the triggering dosage, and GnRH treatment specimens were stripped 10 and 12 hours after hormonal application. We could obtain positive results using CPE with a short capture-induction interval (C-II) with broodstock in mature stages of gonadal development. Percentage of oocytes with peripheral germinal vesicle (%OPGV) and oocyte diameter showed significant differences between groups treated with CPE. Oocytes could be successfully extracted from two females treated with CPE and stripped 12 hours after the last dosage. Semen was only extracted from males treated with CPE. GnRH stimulation did not give positive results because gametes could not be extracted with different doses and C-II used. This work is the first description of semen quality parameters in Gymnotus sp. Future works should focus on combining hormonal induction strategies with CPE and the management of environmental variables.

ABSTRACT Research on the reproduction of snappers helps to manage and conserve them. The spotted rose snapper Lutjanus guttatus is a gonochoric species caught year-round in Navidad Bay, Jalisco, Mexico. This work aims to analyze the reproductive aspects of the spotted snapper L. guttatus caught in Navidad Bay on the southern coast of Jalisco, Mexico. Analyzed fish came from commercial catches. Organisms were sampled monthly from January 1998 to December 2008, and total length, total weight, sex, gonad weight, and gonadal phase were obtained for each specimen. Histological analysis was performed to define the gonadal phase and measure the oocytes' diameter. The total length range in the catches was 14.0 to 61.0 cm; 2889 females and 2792 males were collected for a sex ratio 1.0:0.97. The oocyte development is asynchronous, with a diameter range from 33.9 to 407.9 μm. The testicle is of the lobular type, with a well-defined spermatic duct. A main reproductive season from June to September was identified, although fish with mature gonads were observed in all months. The best condition was observed before the reproductive period. Average lengths at sexual maturity were 30.09 and 30.05 cm for females and males, respectively; the average length of capture in females (32.2 cm) and males (31.7 cm) corresponds to 66.6 and 64.6% of organisms that had reproduced at least once before being captured. Given the importance and continuous capture of L. guttatus in the study area, we recommend further studies to improve the understanding of reproductive and fishing activities.

Abstract: Active extraction of sea-urchin Lytechinus variegatus from the northeast of Venezuela could cause a reduction in the populational density. Therefore, knowledge about somatic growth and gonadal production is relevant for the rational exploitation and sustainable management of sea-urchin populations. During an annual cycle, this study examined the reproductive biology and growth molecular indices (RNA:DNA and Protein:DNA) of a population of L. variegatus sea-urchin from Cariaco Gulf (Venezuela); a marine ecosystem influenced by the seasons of stratification and coastal upwelling. Sea-urchin population was composed of homogeneous sizes, with significant increase of the total fresh mass (MF) and gonadosomatic index (IG) during stratification. Significant regression models were obtained during upwelling and stratification periods, particularly among the MF with testa dimensions and Aristotle’s lantern. Gonadal development was continuous, showing partial spawning during the upwelling period. RNA:DNA ratio increased during stratification season, but not Protein:DNA index. Principal Component Analysis indicated association among molecular growth indices with seston, conversely to phytoplankton biomass, and seawater surface temperature. Reproductive cycle of L. variegatus presented a seasonal pattern associated with temperature and primary productivity; particularly during upwelling it actively spawns, and the gametogenesis is enhanced during stratification, when the metabolic processes are greater.

Resumen: La extracción activa del erizo de mar Lytechinus variegatus en el noreste de Venezuela podría conllevar a una reducción de su densidad poblacional. Por consiguiente, el conocimiento sobre el crecimiento somático y la producción gonadal es de importancia para la explotación racional y el manejo sustentable de sus poblaciones. Durante un ciclo anual, este estudio examinó la biología reproductiva e índices moleculares de crecimiento (ARN:ADN y Proteína:ADN) de una población del erizo L. variegatus en el Golfo de Cariaco (Venezuela); un ecosistema marino regulado por las temporadas de estratificación y surgencia costera. La población de erizos de mar presentó tallas homogéneas, con incrementos significativos en la masa fresca total (MF) y el índice gonadosomático (IG) durante la estratificación. Se obtuvieron modelos de regresión significativos durante los periodos de surgencia y estratificación, particularmente entre la MF en relación con las dimensiones de la testa y linterna de Aristóteles. El desarrollo gonadal fue continuo, mostrando desoves parciales durante el período de surgencia. El cociente ARN:ADN incrementó durante la temporada de estratificación, no así el cociente Proteína:ADN. El Análisis de Componentes Principales indicó asociación entre los índices moleculares de crecimiento con el seston, contrariamente a la biomasa fitoplanctónica, y la temperatura superficial del agua. El ciclo reproductivo del L. variegatus presentó un patrón estacional asociado a la temperatura y productividad primaria; desova activamente durante la temporada de surgencia, y la gametogénesis se potencia durante la estratificación, cuando son mayores los procesos metabólicos.

Resumen Con objeto de examinar la influencia de la depresión endogámica en algunas características productivas del ratón de laboratorio, se reanalizaron 871 registros provenientes de 20 generaciones en una línea con cruza consanguínea estrecha con selección a un índice productivo (CNHS) comparando con una línea sin selección, con cruzamiento endogámico (n= 135). Se calcularon los coeficientes de endogamia (F) para cada generación. En todos los componentes del índice (vida reproductiva, estros postparto fértiles y tamaño de camada), se compararon las dos líneas, en las 15 generaciones disponibles de la no seleccionada, por método de mínimos cuadrados, agrupando cada cinco generaciones. La seleccionada, se analizó en las 20 generaciones, para diferencias intergeneracionales con el mismo método. La depresión endogámica se estimó en todas las generaciones con una regresión lineal de consanguinidad (expresada en 10 %) en todos los componentes. Se observó diferencia significativa (P<0.01) entre líneas en las variables analizadas. Los estros post parto fértiles de la línea seleccionada se mantuvieron constantes, hubo un decremento de 0.331 en la no seleccionada (P<0.01). El índice productivo se mantuvo estable (aumentó 0.071) en la seleccionada, en la no seleccionada disminuyó (0.39) hasta desaparecer (G15). La depresión endogámica impactó en la vida reproductiva de ambas, decreció 4.741 días en la seleccionada vs. 7.718 días en la no seleccionada (P<0.01). En la no seleccionada afectó en mortalidad al destete y ciclo estral, la selección al índice contrarrestó ese impacto, probablemente debido a la selección de genes que favorecen el desarrollo gonadal de los ratones.

Abstract In order to examine the influence of inbreeding depression on some productive characteristics of the laboratory mouse, 871 records were reanalyzed, which were from 20 generations in a line with narrow inbred crossing with selection for a productive index (WOFW) comparing with a line without selection, with inbred crossing (n= 135). Inbreeding coefficients (F) were calculated for each generation. In all the components of the index (reproductive life, fertile postpartum estruses and litter size), the two lines were compared, in the 15 available generations of the non-selected one, by the least squares method, grouping every five generations. The selected one was analyzed in the 20 generations for intergenerational differences with the same method. Inbreeding depression was estimated in all generations with a linear regression of consanguinity (expressed in 10 %) in all components. A significant difference (P<0.01) was observed between lines in the variables analyzed. The fertile postpartum estruses of the selected line remained constant, there was a decrease of 0.331 in the non-selected one (P<0.01). The productive index remained stable (increased 0.071) in the selected one, in the non-selected one it decreased (0.39) until disappearing (G15). Inbreeding depression impacted the reproductive life of both, decreased 4.741 d in the selected one vs 7.718 d in the non-selected one (P<0.01). In the non-selected one, it affected mortality at weaning and estrous cycle, the selection to the index counteracted that impact, probably due to the selection of genes that favor the gonadal development of mice.

Resumo O conhecimento da morfologia testicular e ovariana de uma determinada espécie de peixe é de suma importância, pois através destas análises é possível o desenvolvimento de estudos e técnicas visando o melhoramento de sua reprodução, manejo e comercialização e até mesmo auxiliar em sua conservação. Este estudo realizou a caracterização ovariana e testicular do peixe Amazônico ornamental Serrapinnus kriegi. Um total de três machos e três fêmeas tiveram suas gônadas analisadas através de microscopia óptica. As fêmeas apresentam ovários preenchidos por oócitos em desenvolvimento assincrônico, indicando desova parcelada da espécie. Além disso, observou-se a formação de micrópila e célula micropilar em oócitos em crescimento primário, representando o desenvolvimento precoce do oócito; a zona radiata nos oócitos vitelogênicos finais é mais espessa em comparação a outras espécies relacionadas, evidenciando o desenvolvimento de uma melhor proteção aos embriões, em função das águas turbulentas que caracterizam seu local de desova nos córregos amazônicos. Os machos apresentam testículos do tipo tubular anastomosado com espermatogônias irrestritas, espalhadas por todo o túbulo seminífero. Os dados apresentados elucidam a dinâmica da espermatogênese e oogênese de uma espécie de peixe ornamental amazônica, por meio da descrição das células germinativas masculinas e femininas.

Abstract The knowledge of the testicular and ovarian morphology of a particular fish species is of paramount importance. Such analyze enables the development of studies and techniques aiming the improvement of their reproduction, management, commercialization and even their conservation. This study performed the ovarian and testicular characterization of the ornamental Amazon fish Serrapinnus kriegi. A total of three males and three females had their gonads analyzed by optical microscopy. Females present ovaries filled with oocytes in asynchronous development, indicating partial spawning in the species. Moreover, the micropyle and micropilar cell formation was observed in primary growing oocytes, representing a precocious oocyte development; and the zona radiata in the final vitellogenic oocytes is thicker than other related species, evidencing the development of a better protection to the embryos in function of the waters’ turbulence that characterize it spawning sites in the Amazonian streams. The male specimens’ present anastomosed tubular testes with unrestricted spermatogonia spread along the entire seminiferous tubules. The present data elucidate the dynamic of spermatogenesis and oogenesis of an ornamental Amazonian species, through the description of the male and female germ cells development.

Abstract The females of yellowtail tetra (Astyanax lacustris), known as the freshwater sardine, are approximately 1.33 times larger than males, and thus, all-female monosex culture would increase production and reduce size variability. The present work aimed to identify the optimal dose of 17α-methyltestosterone (MT) to be used in the masculinization of A. lacustris for indirect sex reversal. Three different concentrations of MT (20, 40, and 60 mg/kg of feed in the diet) were fed to the fry for 30 days. Thirty adult individuals from each treatment, including the control (0 mg MT/kg), were evaluated for gonadal development, morphological and histological sexual identification, zootechnical performance, and the possible genotoxic effect caused by prolonged exposure to MT. MT significantly (P<0.01) affected the differentiation of the gonads, with the presence of possible inhibitory effects in all treatments. Intersex individuals were present in the 20 and 60 mg MT/kg treatments. All treatments were able to masculinize A. lacustris and the treatment with the lowest hormone concentration produced the highest percentage of males 76.7%, while the control had 46.7% males. The presence of erythrocyte nuclear alterations indicated a possible cytotoxic effect of MT in treatments 40 and 60 mg MT/kg, however, the use of the hormone did not affect the growth and the survival of the individuals. Thus, the use of MT is a viable option for obtaining neomales as a first step into the production of all-female progenies. Astyanax lacustris, , lacustris) sardine 133 1 33 1.3 thus allfemale female variability 17αmethyltestosterone αmethyltestosterone 17α methyltestosterone α (MT A reversal 20, (20 6 mgkg kg diet 3 days 0 ( MTkg MT/kg) development identification performance P<0.01 P001 P 01 (P<0.01 gonads 2 767 76 7 76.7% 467 46 46.7 4 however Thus progenies 13 1. (2 P<0.0 P00 (P<0.0 76.7 46. P<0. P0 (P<0. 76. P<0 (P<0 P< (P< (P

Abstract Specimens of Cnemidocarpa amphora were collected monthly from the Arabian Gulf from September 2017 to August 2018. Parts of their gonads were prepared for histological testing. The gonads’ diameters varied by month. Each gonad contained many ovarian follicles with different morphologies and was surrounded by several testicular follicles. The ovarian and testicular follicles were separate, although the latter were always present near the former. Repeated measures ANOVA tests were conducted to investigate monthly changes in oocyte stages. In squirts measuring 12–13 cm in length, the gonads measured 30–50 mm from July to August; 20–25 mm from September to October; 15–20 mm from November to February; and 25–40 mm from March to June. Oogonia budded from the germinal epithelium with diameters of 20–30 µm. Previtellogenic oocytes measuring 70–120 µm were characterized by the deposition of small granules of protein around the nucleus, a continuous layer of follicular cuboidal epithelium, and scattered vacuoles in the ooplasm. The measurement of gonads and oocyte diameters were performed by image analysis (Image scope 2.3, Image Line, Inc.) and stage micrometer. The vitellogenic oocytes measured 130–220 µm and the follicular epithelium consisted of flattened and cuboidal layers. Beneath the vitelline membrane, scattered test cells appeared in the ooplasm and different granules of protein and MPS were deposited in the ooplasm. In the later phase, lipid droplets began to appear in the ooplasm. Yolk bodies formed after the impregnation of various granules together and the oocyte was ready to be shed. Before spawning, a yolk membrane appeared above the ooplasm. Post-vitellogenic oocytes, in which the homogeneity of ooplasm was restored, underwent gradual lysis and entered the atretic phase. Different stages of sperm development were present year-round in different follicles of the same squirt; hence, the testes were always mature.

Resumo Amostras de Cnemidocarpa amphora foram coletadas mensalmente no Golfo Pérsico de setembro de 2017 a agosto de 2018. Partes de suas gônadas foram preparadas para testes histológicos. Os diâmetros das gônadas variaram de mês para mês. Cada gônada continha muitos ácinos ovarianos com diferentes morfologias e era circundada por vários folículos testiculares. Os folículos ovarianos e testiculares estavam separados, embora os últimos estivessem sempre presentes próximos aos primeiros. Testes ANOVA de medidas repetidas foram conduzidos para investigar mudanças mensais nos estágios oocitários. Em esguichos medindo de 12 a 13 cm de comprimento, as gônadas mediam de 30 a 50 mm de julho a agosto; 20 a 25 mm de setembro a outubro; 15 a 20 mm de novembro a fevereiro; e 25 a 40 mm de março a junho. Oogônias brotaram do epitélio germinativo com diâmetros de 20 a 30 µm. Oócitos pré-vitelogênicos medindo 70 a 120 µm foram caracterizados pela deposição de pequenos grânulos de proteína ao redor do núcleo, uma camada contínua de epitélio folicular cúbico e vacúolos dispersos no ooplasma. A mensuração dos diâmetros das gônadas e dos ovócitos foi realizada através de análise de imagem (Imagescope 2.3, Image Line, Inc.) e micrômetro de palco. Os oócitos vitelogênicos mediam 130 a 220 µm e o epitélio folicular consistia em camadas achatadas e cúbicas. Abaixo da membrana vitelina, células teste espalhadas apareceram no ooplasma e diferentes grânulos de proteína e MPS foram depositados no ooplasma. Na fase posterior, gotículas lipídicas começaram a aparecer no ooplasma. Corpos de gema formados após a impregnação de vários grânulos juntos e o oócito estava pronto para ser derramado. Antes da desova, uma membrana de vitelo apareceu acima do ooplasma. Oócitos pós-vitelogênicos, nos quais a homogeneidade do ooplasma foi restaurada, sofreram lise gradual e entraram na fase atrésica. Diferentes estágios de desenvolvimento do esperma estiveram presentes o ano todo em diferentes folículos do mesmo esguicho; portanto, os testículos estavam sempre maduros.