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Klaus Reinhold - One of the best experts on this subject based on the ideXlab platform.
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Sperm Number, Spermatophore Weight and Remating in the Bushcricket Poecilimon veluchianus
Ethology, 2010Co-Authors: Klaus Reinhold, Dagmar Von HelversenAbstract:The influence of the intermating interval on sperm number and spermatophore mass was examined in the bushcricket Poecilimon veluchianus. Males that remated after 1 d transferred about 50% of the sperm, but significantly more than 50% of the weight of Spermatophores than males that remated after 2 d. Assuming a constant rate of replenishment of sperm and spermatophore material we concluded that available spermatophore material but not available sperm number influences remating interval in P. veluchianus males.
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mating effort function of the spermatophore in the bushcricket poecilimon veluchianus orthoptera phaneropteridae support from a comparison of the mating behaviour of two subspecies
Biological Journal of The Linnean Society, 1994Co-Authors: Klausgerhard Heller, Klaus ReinholdAbstract:To analyse spcrmatophore function, various aspects of the mating behaviour (e.g. spermatophore mass, duration of sperm transfer, mating frequency) were compared in two subspecies of the bushcricket P. veluchianus. Body mass was significantly different in both subspecies and had a strong effect on spermatophore mass, resulting in a large difference in absolute and relative (percentage of male body mass) spermatophore mass in both subspecies. After copulation the small P. v. minor Spermatophores were consumed much faster by the female than the larger ones of P. v. veluchianus. The time necessary for sperm transfer from the spermatophore to the female spermatheca was much shorter in the subspecies with small Spermatophores than in that with large Spermatophores, and in both subspecies similar to the time required to consume the Spermatophores. Mating frequency varied also between the subspecies and was murh higher in P. v. minor than in P. v. veluchianus. Differences in body mass between the two subspecies therefore resulted in changes in several aspects of mating behaviour. However, despite large differences in the mass of the spermatophore, its main function seems to be to ensure sperm transfer. This can be concluded from the similarity between the duration of sperm transfer and the time period necessary for spermatophore consumption in each of the subspecies. The spermatophore is thus considered to be male mating effort.
Patrizia Jereb - One of the best experts on this subject based on the ideXlab platform.
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male reproductive system and Spermatophores production and storage in histioteuthis bonnellii cephalopoda histioteuthidae a look into deep sea squids reproductive strategy
Deep Sea Research Part I: Oceanographic Research Papers, 2014Co-Authors: Danila Cuccu, Marco Mereu, Angelo Cau, Blondine Agus, Jacopo Culurgioni, Andrea Sabatini, Patrizia JerebAbstract:Abstract Coleoid cephalopods go through a single breeding period in their life cycle, i.e., they are semelparous, although a great flexibility has been observed in their reproductive strategies, which range from simultaneous terminal spawning over a short period at the end of the animal׳s life to continuous spawning over a long period of the animal׳s life. So far, the information available on deep-sea species reproductive strategies is still poor and most of our knowledge about squid reproduction relates to females. In particular, not much is known on what strategy male squids have evolved to store sperm into Spermatophores and adapt to semelparity. In this study an investigation of male reproductive strategy of the deep-sea umbrella squid Histioteuthis bonnellii (Ferussac, 1835) is presented. The reproductive system was examined in 119 males caught in the Sardinian waters (Central Western Mediterranean) and is described for the first time. Results indicate that this species produces and stores Spermatophores over a considerable period of time. The total number of Spermatophores found in the reproductive system ranged between 12 and 3097 and the size of Spermatophores stored by a single individual varied greatly, up to over 300%. Spermatophore length (SpL) gradually decreased towards the distal end of the reproductive system, so that Spermatophores found in the proximal part of Needham׳s Sac were larger than those found in the terminal organ. Body size and SpL of Spermatophores from the proximal part of Needham׳s Sac were positively correlated. Both indices of the sperm mass and of the ejaculatory apparatus decreased with the increase of SpL, while the cement body index increased, indicating that larger Spermatophores contain less sperm and are equipped with larger cement bodies. Up to 64 spermatangia were found, exclusively in the terminal organ. The large size range of mature males (ML: 60.0–198.0 mm; TW: 113.50–2409.00 g) and the variation in spermatophore number and size indicate that in H. bonnellii males the allocation and storage of sperm start early in the individual life and extends in time, while animals continue to grow and produce Spermatophores presumably more successful in attaching to female tissues. This pattern enlarges the time window available for reproduction and likely maximizes the percentage of mating success as the animals grow older and chances of mating events become comparatively lower, due to the basic low density of specimens in the deep-sea environment. Both aspects are potentially indicative of adaptation to the deep sea.
Lammertjan Dam - One of the best experts on this subject based on the ideXlab platform.
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the male reproductive strategy of a deep sea squid sperm allocation continuous production and long term storage of Spermatophores in histioteuthis miranda
Ices Journal of Marine Science, 2010Co-Authors: Hendrik Jan T Hoving, Marek R Lipinski, Lammertjan DamAbstract:Squid are semelparous organisms. Much of what we know about squid reproduction relates to females, because few studies have addressed males and, although males are similarly challenged by semelparity, it remains virtually unknown what tactics squid have evolved to allocate sperm to Spermatophores. The male reproductive strategy of the deep-sea squid Histioteuthis miranda was examined by describing the male reproductive anatomy, which appears unique among cephalopods, and by quantifying spermatophore production and sperm allocation. The species produces and stores Spermatophores over a considerable period of continuous somatic growth. Body size and spermatophore length (SpL) are positively correlated, and the size difference between Spermatophores stored by a single individual was up to 270%. Individuals had between 136 and 2276 Spermatophores inside their reproductive system, and Spermatophores may be stored for as long as 4.5 months. The relationship between SpL and the mass of sperm per spermatophore was polynomial, demonstrating that larger Spermatophores did not necessarily contain more sperm. The unique male morphology and the continuous production and long-term storage of Spermatophores in H. miranda seem to allow the species to increase the window in which reproduction can take place, a strategy that may be valuable in the deep-sea environment.
Danila Cuccu - One of the best experts on this subject based on the ideXlab platform.
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male reproductive system and Spermatophores production and storage in histioteuthis bonnellii cephalopoda histioteuthidae a look into deep sea squids reproductive strategy
Deep Sea Research Part I: Oceanographic Research Papers, 2014Co-Authors: Danila Cuccu, Marco Mereu, Angelo Cau, Blondine Agus, Jacopo Culurgioni, Andrea Sabatini, Patrizia JerebAbstract:Abstract Coleoid cephalopods go through a single breeding period in their life cycle, i.e., they are semelparous, although a great flexibility has been observed in their reproductive strategies, which range from simultaneous terminal spawning over a short period at the end of the animal׳s life to continuous spawning over a long period of the animal׳s life. So far, the information available on deep-sea species reproductive strategies is still poor and most of our knowledge about squid reproduction relates to females. In particular, not much is known on what strategy male squids have evolved to store sperm into Spermatophores and adapt to semelparity. In this study an investigation of male reproductive strategy of the deep-sea umbrella squid Histioteuthis bonnellii (Ferussac, 1835) is presented. The reproductive system was examined in 119 males caught in the Sardinian waters (Central Western Mediterranean) and is described for the first time. Results indicate that this species produces and stores Spermatophores over a considerable period of time. The total number of Spermatophores found in the reproductive system ranged between 12 and 3097 and the size of Spermatophores stored by a single individual varied greatly, up to over 300%. Spermatophore length (SpL) gradually decreased towards the distal end of the reproductive system, so that Spermatophores found in the proximal part of Needham׳s Sac were larger than those found in the terminal organ. Body size and SpL of Spermatophores from the proximal part of Needham׳s Sac were positively correlated. Both indices of the sperm mass and of the ejaculatory apparatus decreased with the increase of SpL, while the cement body index increased, indicating that larger Spermatophores contain less sperm and are equipped with larger cement bodies. Up to 64 spermatangia were found, exclusively in the terminal organ. The large size range of mature males (ML: 60.0–198.0 mm; TW: 113.50–2409.00 g) and the variation in spermatophore number and size indicate that in H. bonnellii males the allocation and storage of sperm start early in the individual life and extends in time, while animals continue to grow and produce Spermatophores presumably more successful in attaching to female tissues. This pattern enlarges the time window available for reproduction and likely maximizes the percentage of mating success as the animals grow older and chances of mating events become comparatively lower, due to the basic low density of specimens in the deep-sea environment. Both aspects are potentially indicative of adaptation to the deep sea.
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Male reproductive system in Neorossia caroli (Joubin 1902) (Cephalopoda: Sepiolidae) from Sardinian waters (western Mediterranean Sea) with particular reference to sexual products
Invertebrate Reproduction & Development, 2011Co-Authors: Danila Cuccu, Marco Mereu, Pamela Masala, Angelo Cau, P. JerebAbstract:The male reproductive system of the bobtail squid Neorossia caroli (Cephalopoda: Sepiolidae) is described in detail, based on observations of 90 mature males caught from 500 to 1600 m depth in Sardinian waters (western Mediterranean Sea). Reproductive organs in mature specimens accounted for up to 6% of total body weight. Of this, 70% was represented by the spermatophoric complex. Up to 83 Spermatophores were found inside the Needham's sac. Mean spermatophore length was 16.7 mm. Sperm mass, cement body, and ejaculatory apparatus represented 63.2%, 13.1%, and 23.7% of the total spermatophore length, respectively. Inverted Spermatophores, empty spermatophore sheaths, and spermatangia were also found in the sac, and their presence is discussed. Spermatangia implanted in several parts of the bodies of males (e.g., head, funnel, and eyes) were recorded and their occurrence is discussed. The spermatophoric reaction was induced in the laboratory by submerging Spermatophores in seawater, and it is described briefly.
Wilson Wasielesky - One of the best experts on this subject based on the ideXlab platform.
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Hemocytic melanization in shrimp Spermatophores
Aquaculture, 2018Co-Authors: André Braga, Luis H. Poersch, Diogo Luiz De Alcantara Lopes, Vitalina Magalhães, Marta Da Costa Klosterhoff, Luis Alberto Romano, Wilson WasieleskyAbstract:Abstract The melanization of shrimp Spermatophores caused by a hemocytic infiltration was demonstrated in this study. A 30-day trial was carried out using wild Farfantepenaeus brasiliensis . On days 0, 15 and 30, the Spermatophores were manually extruded and used for sperm quality and histological analyses. Survival decreased after the extrusion events, whereas spermatophore melanization percentage increased. An inflammatory process characterized by the presence of hemocytes around and embedded in the connective tissue was identified as the trigger to the spermatophore melanization. The hemocytic infiltration was not observed in the sperm mass, but sperm quality was negatively affected.
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Spermatophore replacement of pink shrimp Farfantepenaeus brasiliensis after manual extrusion: Effect of molting
Aquaculture, 2014Co-Authors: André Braga, Diogo L.a. Lopes, Luis H. Poersch, Wilson WasieleskyAbstract:Abstract This study aimed to evaluate Farfantepenaeus brasiliensis spermatophore replacement after manual extrusion and analyze the effect molting has on this process. Three trials were conducted. In the first trial, the replacement of Spermatophores after extrusion was macroscopically evaluated via an analysis of morphological changes in the terminal ampoule during the formation of new Spermatophores. In the second trial, the sperm quality in the different stages of spermatophore replacement identified in the first trial was compared. In the third trial, the replacement time of Spermatophores after extrusion was determined, with and without molting. In all trials, 30 manually extruded wild males were individually stocked in 0.49 m 2 tanks using different samples of randomly selected animals for each trial. The results were obtained by daily visual examination of the gonopore and coxae regions of the fifth pereiopod pair and sperm quality analyses. In trial 1, three successive macroscopic stages of Spermatophores were observed during replacement: unformed, partially formed and formed. In trial 2, the sperm count in formed Spermatophores was significantly higher than that in partially formed Spermatophores, whereas the spermatophore weight was not significantly different. Therefore, spermatophore replacement most likely comprises the following phases: (1) deposition of a primitive spermatophore with all structural components in each terminal ampoule; (2) gradual deposition of spermatozoa; and (3) stiffening of the spermatophore into typical elongate form. Trial 3 demonstrated that after extrusion, Spermatophores are completely formed in 16 days without molting and in 24 h with molting. Spermatophores formed after molting have sperm quality similar to that of gradually formed Spermatophores.
