6 research outputs found
Testicular histology of Anurans that deposit eggs out of the water
Anuran amphibians show the largest diversity of amphibian reproductive modes,many of which imply egg deposition out of the water. This kind of egg depositionrequires specialisations to avoid egg desiccation. Physiological, anatomical and ethological traits integrate to define these modes. In particular, morphological featuresof the urogenital system correlate with these reproductive modes and the environmental conditions where egg-laying occurs. In this study, we describe the testicularhistology and spermatogenesis of the nest-building frog Leptodactylus latinasus, andwe compare it with other species that breed out of water. We found variations in testis size, the thickness of interstitial tissue, tunica albuginea, and peritubular tunics,flagellum length, and in the shape and size of the spermatozoal nucleus. Certainspecifics? characters differed at the species level, but not between families. Suchvariation could be an indicator of spermatozoal performance and environmentalconstraints under which fertilisation takes place.Fil: Pucci Alcaide, Ana. Instituto de Morfología Animalfundación Miguel Lillotucumán; ArgentinaFil: Pucci Alcaide, Franco Jose. Instituto de Morfología Animalfundación Miguel Lillotucumán; ArgentinaFil: Michel, Adriana Azucena. Instituto de Morfología Animalfundación Miguel Lillotucumán; ArgentinaFil: Ponssa, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin
Histology of the ovary and oviduct of the direct developing frog oreobates discoidalis (anura: strabomantidae)
Oreobates discoidalis es un anuro que se reproduce en entornos húmedos y protegidos, depositando sus huevos relativamente grandes directamente en tierra y exhibiendo desarrollo directo. En este estudio, se describe la histología de los órganos sexuales de hembras maduras durante el periodo reproductivo de esta especie. Las hembras de O. discoidalis presentan ovarios compuestos por un solo lóbulo, así como folículos ováricos tipo 3 con sectorización citoplasmática debido a la acumulación de plaquetas vitelinas. En algunos de estos folículos, el epitelio es de tipo cuboidal, y la teca está formada por dos capas en los folículos ováricos tipo 3. En cuanto al oviducto, se observa una predominancia de glicoconjugados ácidos con una distribución laberíntica, organizados de manera fibrilar y granular. Este estudio ha permitido identificar características particulares en la arquitectura de los compuestos glucídicos y en el seguimiento de los compuestos oviductales en hembras de O. discoidalis, las cuales serían adecuadas para un modo de puesta fuera del agua.Oreobates discoidalis is an anuran that reproduces in moist and sheltered habitats, laying relatively large eggs directly on land, and undergoing direct development. In this study, we describe the histology of the sexual organs of mature females during the reproductive period. Our observations reveal ovaries consisting of a single lobe, type 3 ovarian follicles exhibiting sectorization of the cytoplasm due to the accumulation of vitelline platelets, with some of these follicles exhibiting cubic epithelium, and theca formed by two layers in type 3 and 4 ovarian follicles. The oviduct is dominated by acid-type glycoconjugates exhibiting a labyrinthine distribution, organized in a fibrillar and granular manner. This study has revealed distinctive features in the architecture of glucid compounds and the monitoring of oviductal compounds in females of O. discoidalis. These characteristics would be suitable for a water-independent mode of reproduction.Fil: Pucci Alcaide, Ana. Universidad Nacional de Tucumán. Facultad de Ciencias Naturales e Instituto Miguel Lillo; ArgentinaFil: Pucci Alcaide, Franco Jose. Fundación Miguel Lillo; ArgentinaFil: Ponssa, María Laura. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Michel, Adriana A.. Fundación Miguel Lillo; Argentin
The Vesicles of Phyllomedusa sauvagii (Anura: Hylidae) Nest
Phyllomedusa sauvagii lays its eggs surrounded by peculiar vesicles in nests made with tree leaves and, until now, the function of these vesicles was thought to be for maintaining moisture. The histomorphological and histochemical analysis of the oviduct of individuals in ovulatory period, and the study of the vesicles in the oviduct, ovisac and in the nest, showed unexpected results. Vesicles originate from glycoconjugates, proteins and lipids secreted in the PCP and PC and organized in the oviductal lumen and, according to their content, it is possible to recognize at last four types. Furthermore, both in the ovisac and in the nest, vesicles show peculiar relationships with oocites/eggs/embryos through specific communication channels, showing the existence of more complex interactions than previously thought.Fil: Pucci Alcaide, Ana. Fundación Miguel Lillo; ArgentinaFil: Alcaide, María Fernanda. Fundación Miguel Lillo; ArgentinaFil: Pucci Alcaide, Franco. Fundación Miguel Lillo; ArgentinaFil: Lavilla, Esteban Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tucumán; Argentina. Fundación Miguel Lillo; Argentin
Histology and histochemistry of the albumin glands in some foam-nesting anurans
This study deals with the histology and histochemistry of the oviducts of three species of frogs that lay their eggs embedded in a foam nest (Leiuperidae: Physalaemus biligonigerus and Pleurodema borellii; Leptodactylidae: Leptodactylus chaquensis). In all of them the oviducts show five sections [in cephalic-caudal direction, the Pars Recta (PR), Intermediate Proximal Zone (IPZ), Preconvolute Part (PCP), Convolute Part (CP) and Ovisac (O)] identifiable on anatomical and histological basis, and on the peculiarities of their secretions and joined biomolecules. In the section encompassed between the distal portion of PPC and O of the three species it was possible to identify glandular areas that produce glycoconjugates with a dominance of proteins joined to lipids or to glucids that constitute the precursor of the foam. These histologically differentiated glandular aggregations, not yet recorded in species with other modes of oviposition, are named here as “albumin glands”.Fil: Alcaide, MaríaF.. Fundación Miguel Lillo; ArgentinaFil: Lavilla, Esteban Orlando. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; ArgentinaFil: Pucci Alcaide, Ana. Fundación Miguel Lillo; Argentin