31 research outputs found

    Spermatogenesis and sperm structure in the black-striped pipefish <i>Syngnathus abaster</i> (Teleostei, Syngnathidae) = Spermatogenesi e struttura degli spermatozoi in <i>Syngnathus abaster</i> (Teleostei, Synghathidae)

    Get PDF
    The gonads of adult males of the black-striped pipejish Syngnathus abaster were observed during the reproductive season to describe mature sperm both quantitativel/y and qualitatively. The results show that: a) the sperms number is always very low and, does not vary significantly during the reproductive season; b) all mature sperms observed may be assigned to the introsperm-like type. These data suggest that the unique and functional sperm of Syngnathids pertain to the introsperm type typical of internally fertilizing teleostean bony fishes

    First insights on the mitochondrial genetic variability of Lightiella magdalenina (Crustacea), the sole Mediterranean cephalocarid species

    Get PDF
    Background: Here we report the first insight into the mitochondrial (Cytochrome c Oxidase subunit I - COI and Cytochrome b - Cyt b) genetic variation of the only Mediterranean cephalocarid Lightiella magdalenina. Findings: COI sequences provide a scenario of low intraspecific variability, while significant genetic divergence occurs between L. magdalenina and L. incisa. Interestingly, Cyt b sequences reveal a higher degree of intraspecific variability, with no shared haplotypes between the sites considered. Conclusions: In the future, COI and Cyt b molecular markers could be used as valuable tools to shed new light into the extant species within the genus Lightiella thus providing molecular support to the taxonomical identifications carried out on a morphological basis

    Reproductive system of <i>Lightiella magdalenina</i> (Crustacea, Cephalocarida) = Apparato riproduttore in <i>Lightiella magdalenina</i> (Crustacea, Chefalocarida)

    Get PDF
    The aim of this study was to describe the morphology of the reproductive system of Lightiella magdalenina the only cefalocarid species known from Europe. Two adult specimens and one larval stage of L. magdalenina were analysed with light microscope and findings compared with available data from H. macracantha

    Study of animal remains dug out during the excavations of a Nuragic village in Sardinia

    Get PDF
    This paper presents the results of the zooarchaeological analysis of the faunal materials brought to light during the excavations set up in the Nuragic village surrounding the Santu Antine Nuraghe, near Torralba (Sassari), Sardinia. Precisely, the remains come from the structure of the village named by archaeologists hut 12. They are 779 specimens out of thousands animal remains from the whole archaeological site. The majority of the rests belong to sheep (Ovis aries) or goats (Capra hircus), cattle (Bos taurus), pigs (Sus scrofa) and deers (Cervus elaphus). Such material may provide suggestions about the productive use of animals in the village and point out the importance of the economical management of animals in the Nuragic society. Indeed, many remains show signs with human origin, which testify that the hut may have been a workplace where bone fragments were processed to obtain different kind of tools

    Autophagic processes increase during senescence in cultured sheep neurons and astrocytes

    Get PDF
    A possible response to aging is autophagy, a self-digestion process in which portions of cytoplasm are encapsulated by double-membrane-bound structures and delivered to lysosome for degradation. A previous work of our group showed that astrocytes under starving conditions are characterized by a higher upregulation of the marker of autophagy LC3 II than neurons. Aim of the present work was to evaluate LC3 II expression in an aging model consisting in fetal sheep neurons and astrocytes at 10, 20 and 30 days of culture. Such model has been validated by a remarkable activity of β-galactosidase, commonly used to reveal cell aging. LC3 II immunoreactivity in neurons and astrocytes progressively increased with time but differences were observed on the basis of cell density. Indeed, LC3 II immunoreactivity is higher in clusters of neurons and astrocytes and this may be due to the fact that cell-cell contact would represent a second stress in addition to aging itself. Both cell types displayed a reduction in LC3 II signal in nuclei, and a corresponding strengthening in the cytoplasm with time. This may be due to the need of aged cells to remove damaged cytoplasmic components through autophagic processes. Such variation in LC3 II localization could be caused by migration from the nucleus to cytoplasm as well as possible de novo intracytoplasmic production. The present work based on sheep neural cells in vitro may represent a helpful tool in the studies on aging processes in which autophagy plays a remarkable role

    Anatomical study of animal remains from Phoenician-Punic amphorae found in the Santa Giusta Pond, Sardinia (Italy)

    Get PDF
    During the underwater excavations carried out in the Santa Giusta Pond, near Oristano, Sardinia, a significant amount of Phoenician- Punic materials was brought to light including amphorae (dating back to 7th-2nd century BC) and vegetal and animal remains. All of these archaeological finds may come from Othoca, an important Phoenician- Punic city on the eastern shore of the pond, geographically corresponding with the modern-day town of Santa Giusta. Animal materials consist of more than 3000 very well-preserved remains, belonging to sheep (Ovis aries), goat (Capra hircus) and cattle (Bos taurus). Bone analyses allowed reconstructing the slaughtering methods, as well as manipulation procedures carried out to preserve meat in order to be exported overseas. Although pig (Sus scrofa) played an important economical role in other Sardinian Phoenician-Punic settlements, in this archaeological context this species is absent, suggesting that the meat contained in the amphorae was probably destined to other areas of the Mediterranean basin, where people did not eat pork

    Molecular data on two mitochondrial genes of a newly discovered crustacean species (<i>Lightiella magdalenina</i>, Cephalocarida)

    No full text
    Cephalocarida is a rare and poorly known class of small benthic crustaceans, consisting of only eleven species belonging to five genera. Thus far, only one species (Hutchinsoniella macracantha) has been studied at molecular level. We report the partial sequences of two phylogenetically important mitochondrial genes (Cytochrome c Oxidase I and Cytochrome b) from the newly discovered Mediterranean species, Lightiella magdalenina. The genetic relationships between the two cephalocarid species are discussed

    Reproductive system morphology of <i>Lightiella magdalenina</i> (<i>Crustacea</i>, <i>Cephalocarida</i>): functional and adaptive implications

    No full text
    The reproductive systems of adults and larvae of Lightiella magdalenina were examined. Lightiella magdalenina, similar to the best-known cephalocarida species Hutchinsoniella macracantha, is a simultaneous hermaphrodite. Although the morphology of their reproductive system is similar, L. magdalenina differs from H. macracantha in exhibiting reduced fecundity: it lays one egg, not two, per reproductive event. This is due to asynchronous development of the oocytes inside the paired female reproductive structures, which determines the maturation of a single egg at a time. The reduced fecundity of L. magdalenina could be offset by the precocious release of oocytes from the germarium, which begins the vitellogenetic process during the last larval stages. Due to this process, after their last moult, reproductive adults can have a large number of advanced vitellogenic oocytes, reducing the time required for their maturation. A possible adaptive relationship between the halved fecundity with pre- and post-hatching parental care is discussed
    corecore