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1.
Braz. j. biol ; 77(1): 185-190, Jan-Mar. 2017. tab, graf
Article in English | LILACS | ID: biblio-839170

ABSTRACT

Abstract This study investigated the effects of tributyltin (TBT) on the morphology of the genital system of the gastropod Stramonita rustica in southern Bahia, Brazil. For this, 330 specimens were collected during the summer of 2014 at eight sampling points to ascertain whether male sex organs had developed in addition to the complete female genital tract in females (= imposex). The analyses were made under a stereoscopic microscope. Imposex and their associated indexes, and the sterile females, exhibited the highest rates in harbors and shipyards areas. Despite the total ban of TBT in anti-fouling paints on a global scale since 2003, the results of this and other studies indicate the continued use of those paints on the Brazilian coast. This shows the inefficiency of existing legislation and the need to strengthen enforcement of the ban.


Resumo Este estudo investigou os efeitos de tributil-estanho (TBT) sobre a morfologia do sistema genital do gastrópode Stramonita rustica (Lamarck, 1822) no Litoral Sul da Bahia, Brasil. Para isso, 330 espécimens foram coletados durante o verão de 2014 em oito pontos de amostragem, para verificar se os órgãos sexuais masculinos tinham se desenvolvido para além do trato genital feminino completo (= imposex). As análises foram feitas sob um microscópio estereoscópico. O imposex e seus índices associados, assim como as fêmeas estéreis, apresentaram as maiores taxas em áreas portuárias e estaleiros. Apesar da proibição total do TBT em tintas anti-incrustantes em escala global desde 2003, os resultados deste e de outros estudos indicam a continuidade de uso dessas tintas na costa brasileira. Isso mostra a ineficácia da legislação vigente e reforça a necessidade de se cumprir integralmente o banimento.


Subject(s)
Animals , Male , Female , Paint/toxicity , Disorders of Sex Development/chemically induced , Trialkyltin Compounds/toxicity , Gastropoda/drug effects , Seasons , Disorders of Sex Development/veterinary , Water Pollutants, Chemical/analysis , Water Pollutants, Chemical/toxicity , Brazil , Environmental Monitoring/methods
2.
Rev. biol. trop ; 62(2): 523-532, Jun.-Aug. 2014. ilus, tab
Article in Spanish | LILACS | ID: lil-715449

ABSTRACT

Voluta musica is a dioecious marine gastropod endemic of the South Caribbean. Tributyltin (TBT) and copper (Cu) are potential inducers of imposex, an endocrine disorder by which females develop a penis and/or vas deferens. The goal of this work was to determine the imposex incidence in V. musica populations from Northeastern Península de Araya. For this, we selected three sites (Isla Caribe, Isla Lobos and Bajo Cuspe) and made monthly samplings of 15 snails in each site, during one year, and determined: (1) sizes; (2) sex and imposex incidence and (3) the Relative Penis Length Index (RPLI). We also performed histological analysis of the gonads, and measured TBT and Cu concentrations in sediments from the studied localities. Our results showed that the total number of sampled females affected by imposex was 24.5% at Isla Caribe, 12% at Isla Lobos, and none at Bajo Cuspe. In sediments, Cu was detected mostly in Isla Lobos. The female gonads with imposex did not show any development of male cells in any of the sampled sites. The higher percentage of females with imposex matched with the higher boat traffic locality, and higher TBT level (Isla Caribe). No esterilization was evident in this work, nevertheless, the presence of TBT and Cu in the sediments and females with imposex were considered as a potential threat to V. musica populations in this region. In Venezuela there is no control over this particular issue, possibly because of the lack of information and research in this topic, but certainly, this information will be useful in biodiversity conservation policies.


Voluta musica es un gasterópodo dioico endémico del Caribe sur. El TBT y el Cu, son potenciales causantes del imposex, fenómeno donde las hembras desarrollan un pene y/o vaso deferente. El objetivo fue determinar la incidencia de imposex en V. musica en el noreste de la Península de Araya. Se seleccionaron tres localidades y se captura-ron mensualmente 15 individuos durante un año para determinar: (1) talla de los individuos; (2) sexo y presencia de imposex; (3) índice Largo Relativo del Pene (RPLI). Se realizó histología de la gónada de los individuos. Se determinó TBT y Cu en el sedimento de cada localidad. En Isla Caribe, el 24.5% de las hembras presentó imposex, y se halló 3.9ngSn/g de TBT; en Isla Lobos, el 12% de las hembras desarrollaron imposex; en Bajo del Cuspe no se observó imposex. Se halló Cu en mayor concentración en Isla Lobos. Las gónadas femeninas con imposex no demos-traron masculinización. El mayor porcentaje de imposex coincide con la localidad de mayor tráfico de embarcacio-nes y con mayor nivel de TBT (Isla Caribe). No se eviden-ció esterilización, sin embargo la presencia de TBT, Cu e imposex son potenciales amenazas para las poblaciones de V. musica en la región. Hasta ahora, en Venezuela no se está tomando ninguna medida de control sobre este tema en particular, posiblemente por la escasez de información y orientación de las investigaciones hacia este tema, pero que sin duda se debería tomar en cuenta en las políticas para la conservación de la biodiversidad.


Subject(s)
Animals , Female , Male , Disorders of Sex Development/veterinary , Gastropoda/drug effects , Gonads/drug effects , Trialkyltin Compounds/toxicity , Water Pollutants, Chemical/toxicity , Disorders of Sex Development/chemically induced , Environmental Monitoring , Gonads/abnormalities , Venezuela
3.
Neotrop. ichthyol ; 9(3): 547-558, 2011. ilus, graf, tab
Article in English | LILACS | ID: lil-600882

ABSTRACT

There is little knowledge on the reproduction of the genus Alphestes. The reproduction of the Mutton hamlet, Alphestes afer, sampled in Pernambuco reefs (Brazil) was studied based on macroscopic analysis during reproductive period and histological analysis of gonad material from March 2008 to October 2009. This study showed that A. afer is a diandric, protogynous hermaphrodite. Sex change followed protogynous mode in two pathways: primary males formed from immature female individuals or secondary males formed from resting, ripe or spent female individuals. The numerical distribution of gonad classes by size indicated that females from 11-18 cm L T were immature while females from 16-25 cm L T and males from 12-22 cm L T were in various stages of gonadal development. Individuals identified as immature bisexual and transitional (presenting both ovarian and sperm tissue) were sized from 16-24 cm L T. Size of first reproduction for females was 18 cm L T and for males was 12 cm L T. Alphestes afer showed multiple spawning, with spawning season period from August to December 2008 and from August to October 2009. The sex-ratio (females: males) in 2008 and 2009 was 0.94:1 during the months of spawning season. Males were smaller than females, reaching maximum size of 22 cm compared to 25 cm observed for females. Males showed a high sperm competition rank (3.8), suggesting intense sperm competition. This latter is a possible indication of a shift in the mating group structure from paired to group spawning. The presence of small males added to high sperm competition index, suggest that this species, while retaining the protogynous pattern, has a reproductive strategy similar to gonochorist epinephelids.


Há pouco conhecimento sobre a reprodução do gênero Alphestes. A reprodução do sapé Alphestes afer coletado nos recifes de Pernambuco (Brasil) foi estudada baseada em análises macroscópicas durante o período reprodutivo e análises histológicas das gônadas de março de 2008 a outubro de 2009. Esse estudo mostrou que Alphestes afer é uma espécie hermafrodita diândrica. A mudança de sexo seguiu o modo protogínico em dois caminhos: machos primários transformados de fêmeas imaturas ou machos secundários transformados de fêmeas em repouso, maduras ou esgotados. A distribuição numérica por classe de tamanho indicou que fêmeas de 11-18 cm L T foram imaturas; fêmeas de 16-25 cm L T e machos de 12-22 cm L T foram de vários estádios de desenvolvimento gonadal. Indivíduos identificados como imaturos bissexuais e transicionais (ambos apresentando tecido ovariano e espermático) foram de 16-24 cm L T de comprimento. O tamanho de primeira maturação da fêmea foi 18 cm L T e do macho foi 12 cm L T. Alphestes afer mostrou desova múltipla, com período de desova de agosto a dezembro de 2008 e de agosto a outubro de 2009. A proporção sexual (fêmeas: machos) em 2008 e 2009 foi 0,94:1 durante os meses de desova. Machos foram menores que as fêmeas, alcançando o tamanho máximo de 22 cm L T comparados ao tamanho máximo de 25 cm L T das fêmeas observadas. Machos tiveram o rank de competição espermática alto (3,8) sugerindo intensa competição espermática, o que é uma possível indicação da mudança na estrutura do grupo de acasalamento de desova em pares para desova em grupo. A presença de machos pequenos com alto índice de competição espermática sugere que esta espécie, enquanto retém o padrão protogínico, possui uma estratégia reprodutiva similar aos epinefelídeos gonocoristas.


Subject(s)
Animals , Fishes/anatomy & histology , Disorders of Sex Development/surgery , Disorders of Sex Development/genetics , Disorders of Sex Development/veterinary , Sexual Maturation
4.
Arq. bras. med. vet. zootec ; 61(6): 1478-1481, dez. 2009. ilus
Article in Portuguese | LILACS | ID: lil-537283

ABSTRACT

Hermaphroditism is a term used to describe animals that have genitals of both genders. This anomaly has been described in reptiles such as lizards and snakes. The jabuti species Geochelone carbonaria hull has a high and very concave bone which is covered by corneal plates with yellow spots at the center, and collect the neck caudally into the hull. Although sexual dimorphism is externally quite clear, the females have straight plastron, while the male presents a clear concave plastron that serves to facilitate the mounting and a well developed penis having the size of the animal body. However, hermaphroditism in this species can only be confirmed with additional exams.


Subject(s)
Animals , Female , Disorders of Sex Development/veterinary , Oxytocin/administration & dosage , Reptiles/anatomy & histology , Radiography/methods , Diagnostic Techniques and Procedures/veterinary
5.
Int. j. morphol ; 27(2): 509-514, June 2009. ilus, tab
Article in Spanish | LILACS | ID: lil-563104

ABSTRACT

La costa del Pacífico sudoriental es el hábitat de las 13 especies de lapas descritas del subgénero Fissurella Brugière. En estas especies no existe dimorfismo sexual, los animales son dioicos, el sexo se reconoce explorando directa o indirectamente las gónadas y no tienen procesos de reversión sexual. La presencia de un organismo de Fissurella crassa con gónada formada por porciones de ovario y otras de testículo con capacidad para generar óvulos y espermatozoides, evidencia la potencialidad que los organismos de Fissurella poseen para desarrollar el hermafroditismo funcional. Sin embargo, el presente hallazgo no permite inferir si el agente desencadenante del desarrollo sincrónico funcional de la gónada hermafrodita es un factor endógeno y/o asociado a algún evento exógeno medio ambiental.


The coast of the Southeastern Pacific is the habitat for 13 species of described keyhole limpets of the subgenus Fissurella Brugière. In these species sexual dimorphism does not exist, the animals are dioicos, the sex is recognized exploring directly or indirectly the gonads and they do not have processes of sexual reversion. The presence of an organism Fissurella crassa with portions of ovary and testicle with ability to generate ova and sperms, demonstrates the potential that Fissurella's organisms possess to develop functional hermaphroditism. Nevertheless, the present find does not allow to infer if the trigger agent of the synchronous functional development of the hermaphrodite gonad is a factor endogenous and/or associated with any exogenous environmental event.


Subject(s)
Animals , Disorders of Sex Development/etiology , Disorders of Sex Development/genetics , Disorders of Sex Development/veterinary , Mollusca/anatomy & histology , Mollusca/physiology , Mollusca/genetics , Gonads/anatomy & histology , Gonads/embryology , Gonads/physiology , Gonads/ultrastructure , Sex Determination Analysis
6.
Veterinary Medical Journal. 1998; 46 (1): 89-93
in English | IMEMR | ID: emr-50040
7.
Braz. j. vet. res. anim. sci ; 31(3/4): 267-72, 1994. ilus
Article in Portuguese | LILACS | ID: lil-240031

ABSTRACT

Relata-se um caso esporádico de hermafroditismo parcial em suíno da raça Landrace. Ao exame, constatou-se que o animal apresentava um nítida prega cutânea que se prolongava desde a regiäo abdominal, onde existia um pênis rudimentar, até atingir a borda anal. Constatou-se, ainda, um aumento significativo do volume abdominal que à percussäo, revelava conter líquido no seu interior. A necrópsia, observou-se que o aparelho reprodutor feminino era incompleto, constituído de 2 ovários aparentemente normais, uma trompa de aspecto anatômico também normal, anexa à qual se observava um testículo e epidídimo atrofiados. A trompa contralateral mostrava-se muito aumentada de volume e no seu interior constatou-se a existência de um fluido espesso, incolor e inodoro. Näo foi verificada a existência de corpo uterino bem como de tubo vaginal e da vulva, visto que as trompas terminavam em fundo cego. Da mesma forma, verificou-se ausência dos demais anexos do aparelho reprodutor masculino. A histopatologia revelou que os ovários apresentavam estruturas normais, enquanto o testículo mostrava-se com acentuada hipoplasia e aplasia das células germinativas e túbulos seminíferos


Subject(s)
Animals , Disorders of Sex Development/veterinary , Swine
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