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1.
PeerJ ; 11: e15094, 2023.
Article in English | MEDLINE | ID: mdl-36974138

ABSTRACT

Three sexually mature goshawks reared in captivity and imprinted on humans to express reproductive behavior according to the cooperative method were studied for three consecutive breeding seasons to assess the quality of their sperm. The following parameters were analyzed: ejaculate volume and sperm concentration, motility, viability, and morphology. Ejaculate volume, sperm concentration and motility fluctuated along the reproductive season, revealing the greatest quality of the reproductive material at full springtime (i.e., April). Motility of the sperm collected in March strongly reduced with age, contrary to samples collected in April or May. Sperm viability was not influenced by either age or month of collection within each season. Ultrastructural investigations provided information on normal sperm morphology for the first time in this species. The morphological categories of sperm defects in fresh semen, present at low percentages, are also described. Functional analyses (perivitelline membrane assay and artificial inseminations) confirmed the good quality of the semen obtained using the cooperative method. The reported data provide the basis for further studies aimed at developing protocols to improve the outcome of artificial insemination and semen cryopreservation in the goshawk as well as other bird of prey species.


Subject(s)
Eagles , Hawks , Raptors , Animals , Humans , Male , Semen , Sperm Motility , Reproduction
2.
Zootaxa ; 4881(3): zootaxa.4881.3.3, 2020 Nov 20.
Article in English | MEDLINE | ID: mdl-33311301

ABSTRACT

Eight new species of Duplominona (Platyhelminthes, Proseriata, Monocelididae) are described from the Pacific coast of Panama. They differ from their congeners in the detailed morphology of hard structures associated with the copulatory organ. Duplominona basidilatata n. sp. has a cirrus provided with 5-6 rows of triangular spines, 3-8 µm long, with a large, flat, poorly sclerotized basis. D. hystricina n. sp. has 10-12 rows of needle-shaped spines, 3.5-15 µm long, with a swollen basis. The cirrus of D. hyperhystricina n. sp. is provided with 20-25 rows of slender spines 1.5-9 µm long, with a recurved distal tip. In D. veracruzensis n. sp., cirrus spines increase abruptly in size, from 1.5-2 µm to 6-7 µm. D. uniserta n. sp. has a very long seminal vesicle and a small cirrus, provided with one girdle of hook-shaped spines, 3-5 µm long. D. macrodon n. sp. has one girdle of large, triangular spines, 8-18 µm long. Both D. trimera n. sp. and D. pseudotrimera n. sp. have a tripartite tail, and their cirrus is provided with a stylet. In D. trimera n. sp., the stylet is surrounded by 15-20 rows of spines, 6.5-10 µm long, while D. pseudotrimera n. sp. has 6-8 rows of large spines, 7-22 µm long. D. uniserta n. sp. and D. aduncospina Curini-Galletti, 2019 from the Caribbean coast of Panama have few rows of morphologically nearly identical spines, and are possible candidates as trans-isthmian geminate species. The presence of species with a tripartite tail on both sides of the Isthmus of Panama suggests the possibility of further geminate species pairs; however, no support could be obtained on the basis of the morphology of their hard structures. Five of the eight new species of Duplominona have been found in a single locality, and the diversity of genus along the Pacific coast of Panama may be far higher than present contribution suggests.


Subject(s)
Perciformes , Platyhelminths , Animals , Panama
3.
Eur J Histochem ; 62(2): 2891, 2018 Apr 03.
Article in English | MEDLINE | ID: mdl-29943951

ABSTRACT

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 ß-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.


Subject(s)
Astrocytes/pathology , Autophagy , Cellular Senescence , Fetus/pathology , Fluorescent Antibody Technique/methods , Microtubule-Associated Proteins/metabolism , Neurons/pathology , Animals , Astrocytes/metabolism , Cell Nucleus/metabolism , Cell Nucleus/pathology , Cells, Cultured , Fetus/metabolism , Neurons/metabolism , Sheep
4.
J Biol Res (Thessalon) ; 21(1): 5, 2014 Dec.
Article in English | MEDLINE | ID: mdl-25984488

ABSTRACT

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.

5.
Arthropod Struct Dev ; 39(4): 251-60, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20109581

ABSTRACT

The crop of adult Phormia regina consists of a duct that diverges from the esophagus, just in front of the cardia, and extends ventrally and posteriorly into the thorax and abdomen where it forms a bilobed sac. Flattened epithelial cells produce the cuticular lining of the crop. When empty, or partially full, the epithelial cells and cuticular lining form folds extending into the lumen, thus providing for expansion as the crop sac fills. Covering the sac on the hemolymph side is a layer of anastomosed, intrinsic muscles connected to one another by intercellular cytoplasmic bridges. Mitochondria are located at the periphery of the sarcomere. Also inside the sarcomere are glycogen, sarcoplasmic reticula, and transverse tubular systems (T-system). I, A, and Z-bands are present and the Z-bands are not in register making the muscle-type supercontractile. Important structures, not previously researched and associated with the crop muscles, are the crop nerves. Coming off the corpora cardiaca, and running down each side of the crop duct, is a pair of nerves, each housing several axons. These nerves extend to and branch over the crop sac. Here they penetrate the muscle mass and form neuromuscular junctions where electron-dense droplets of neurosecretion are released. Based on the literature, and research in our laboratory, it has now been shown that these nerves carry adipokinetic hormone, Drosophila insulin-like peptide, and a dromyosuppressin-like neuropeptide.


Subject(s)
Diptera/ultrastructure , Animals , Microscopy, Electron, Scanning , Microscopy, Electron, Transmission
6.
J Morphol ; 228(1): 61-75, 1996 Apr.
Article in English | MEDLINE | ID: mdl-29852596

ABSTRACT

The female reproductive system of Eupolybothrus fasciatus (Newport) (Chilopoda Lithobiomorpha) includes three types of well-developed accessory glands, viz. large glands, small glands, and the periatrial gland. External morphology and the ultrastructural organization of these glands have been investigated by light and electron microscopy. The small and large glands are paired and have coiled ducts that open, respectively, into and externally to the genital atrium. By contrast, the periatrial gland is unpaired and is located on the ventral wall of the atrium into which it opens via several small canals. Ultrastructural features show that all three glands consist of two different types of cells: secretory cells and ductule cells. The secretary cells contain prominent secretory granules and are similar to a class of insect epidermal gland cells (class 3) organized as acini surrounding an extracellular lumen into which microvilli project. The granules, which have different morphological features in each gland, could be responsible for important differential functions such as producing a sexual attractant, providing a coating material that protects eggs laid on the ground, and contributing to a fluid that digests spermatophores. © 1996 Wiley-Liss, Inc.

7.
Dev Growth Differ ; 36(2): 197-207, 1994 Apr.
Article in English | MEDLINE | ID: mdl-37280956

ABSTRACT

Developing embryos of the stick insect Carausius morosus were examined ultrastructurally with a view to studying vitellophage invasion of the yolk mass during and after germ band formation. Newly laid eggs in C.morosus have a unique yolk fluid compartment surrounded by a narrow fringe of cytoplasm comprising several small yolk granules. Vitellophages originate mainly from a thin layer of stem cells, the so-called yolk cell membrane, interposed between the germ band and the yolk mass. Throughout development, a thin basal lamina separates the yolk cell membrane from the overlying embryo. Vitellophages extend from the yolk cell membrane with long cytoplasmic processes or filopodia to invade the central yolk mass. Along their route of entrance, filopodia engulf portions of the yolk mass and sequester it into membrane-bounded granules. As this process continues, the yolk mass is gradually partitioned into a number of yolk granules inside the vitellophages. Later in development, the yolk cell membrane is gradually replaced by the endodermal cells that emerge from the anterior and posterior embryonic rudiments. From this stage of development onwards, vitellophages remain attached to the basal lamina through long filopodia extending between the endodermal cells. Yolk confined in different vitellophagic cells appears heterogeneous both in density and texture, suggesting that yolk degradation may be spatially differentiated.

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