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Sex determination (SD) shows huge variation among fish and a high evolutionary rate, as illustrated by the Pleuronectiformes (flatfishes). This order is characterized by its adaptation to demersal life, compact genomes and diversity of SD mechanisms. Here, we assembled the Solea senegalensis genome, a flatfish of great commercial value, into 82 contigs (614 Mb) combining long- and short-read sequencing, which were next scaffolded using a highly dense genetic map (28,838 markers, 21 linkage groups), representing 98.9% of the assembly. Further, we established the correspondence between the assembly and the 21 chromosomes by using BAC-FISH. Whole genome resequencing of six males and six females enabled the identification of 41 single nucleotide polymorphism variants in the follicle stimulating hormone receptor (fshr) consistent with an XX/XY SD system. The observed sex association was validated in a broader independent sample, providing a novel molecular sexing tool. The fshr gene displayed differential expression between male and female gonads from 86 days post-fertilization, when the gonad is still an undifferentiated primordium, concomitant with the activation of amh and cyp19a1a, testis and ovary marker genes, respectively, in males and females. The Y-linked fshr allele, which included 24 nonsynonymous variants and showed a highly divergent 3D protein structure, was overexpressed in males compared to the X-linked allele at all stages of gonadal differentiation. We hypothesize a mechanism hampering the action of the follicle stimulating hormone driving the undifferentiated gonad toward testis more...

Aim of study: To describe the common behaviour of flathead grey mullet (Mugil cephalus) under rearing conditions. Area of study: Tepic, Mexico. Material and methods: Behaviours exhibited by mullets were videorecorded with submersible cameras installed inside of three tanks. A total of 690 min per day (07:30 - 18:30 h) were recorded per tank during a week. Afterwards, the different behaviours exhibited by juvenile M. cephalus were described, identified and characterized in an ethogram and grouped into two categories: a) locomotion, including three different observed behaviours (resting, swimming and fast swimming) and b) feeding, including three behaviours (surface feeding, bottom feeding and rubbing). Each of the behavioural variables were quantified. Main results: M. cephalus is a species with a constant locomotion associated to feeding, since fish showed continuous movement during most of day light period. On the contrary, fish exhibited reduced movement during dark periods. Mullets were observed to be a non-aggressive fish species under conditions of the present study, since the absence of dominance and aggression towards conspecifics was observed, which suggested a high predisposition for adaptation to captivity. Finally, behavioural frequencies of grey mullet juveniles were similar among the three tanks for most of the behavioural variables analysed (p>0.05) except for the variable bottom feeding (p=0.02). Research highlights: Results from this study could be of interest for the aquaculture industry to optimize rearing techniques and welfare for the production of grey mullet. more...

[ES] Solea senegalensis, exhibe disfunciones reproductivas en cautiverio que limitan la producción. Los machos salvajes y F1 producen poco volumen de semen y al momento de extracción de gametos es casi inevitable la contaminación del esperma con orina, haciendo que la calidad de los espermatozoides disminuya rápidamente. Esto conlleva a que sea dificultoso el almacenamiento. El objetivo del presente estudio fue mejorar la recolección de semen y los protocolos para el almacenamiento corto refrigerado de esperma de Solea senegalensis. Se examinaron muestras de 41 machos en total divididas en 3 experimentos. En el primer experimento se examinó el efecto del lavado de los espermatozoides. Para eso se substituyó tras el centrifugado el plasma seminal por solución Leibovitz. En el segundo experimento se examinó el efecto de la composición de los medios extensores en la calidad de los espermatozoides durante el almacenamiento. El medio extensor de solución Leibovitz se usó para lavar los espermatozoides. Para mejorar la composición del medio extensor, se prepararon soluciones agregando antioxidantes (BHT) y nutrientes (glutamina y glicina). En el tercer experimento, para mejorar la recolección de esperma, los gametos se recolectaron directamente en una jeringa que contenía el medio extensor Leibovitz. Los parámetros de calidad como el porcentaje de motilidad, las concentraciones de trifosfato de adenosina (ATP) y peroxidación lipídica en forma de malondialdehído (MDA) se midieron en relación con el tiempo de almacenamiento en los diferentes tratamientos. En el primer experimento, efecto del lavado en la calidad del esperma, los resultados muestran que los tratamientos de lavado con solución Leibovitz una sola vez (D-1C) y diluido (D) no tienen diferencias significativas entre ellos, y que ambos tratamientos tiene un efecto significativo respecto al tratamiento de lavado dos veces (D-2C). El mejor resultado en cuanto al mantenimiento de la motilidad por mayor tiempo (24h) f, [EN] Solea senegalensis, exhibits reproductive dysfunctions in captivity that limit production. The wild and F1 males produce little semen volume and the time of extraction of the gametes it is inevitable that the sperm is contaminated with urine causing the quality of the sperm to rapidly decrease making storage difficult. The objective of this study was to improve semen collection and protocols for short term refrigerated storage of sperm from Solea senegalensis. Samples from 41 males were examined in total, divided into 3 experiments. In the first experiment the effect of sperm washing was examined, in the second experiment the effect of the composition of the extender media on the quality of the sperm during storage was examined. Leibovitz solution extender medium was used to wash sperm. To improve the composition of the extensor medium, solutions were prepared with antioxidants (BHT) and nutrients (glutamine and glycine). In the third experiment, to improve sperm collection, the gametes were collected directly in a syringe containing Leibovitz extender medium and the quality of the sperm was compared with the gametes collected without extender. Quality parameters such as motility percentage, concentrations of adenosine triphosphate (ATP) and lipid peroxidation in the form of malondialdehyde (MDA) were measured in relation to storage time in the different treatments. In the first experiment, effect of washing on sperm quality, the results show that washing treatments with Leibovitz solution once (D-1C) and diluted (D) have no significant differences between them, and that these two treatments have a significant effect on the wash twice treatment (D-2C). The best result of maintaining motility for a longer time (24h) was the dilute treatment (D), and the wash once treatment (D-1C) had the best curvilinear speed (VCL) at 24h. In the second experiment, composition of the extender media and its effect on sperm quality during storage, significant differences were fou more...

[ES] Solea senegalensis, exhibe disfunciones reproductivas en cautiverio que limitan la producción. Los machos salvajes y F1 producen poco volumen de semen y al momento de extracción de gametos es casi inevitable la contaminación del esperma con orina, haciendo que la calidad de los espermatozoides disminuya rápidamente. Esto conlleva a que sea dificultoso el almacenamiento. El objetivo del presente estudio fue mejorar la recolección de semen y los protocolos para el almacenamiento corto refrigerado de esperma de Solea senegalensis. Se examinaron muestras de 41 machos en total divididas en 3 experimentos. En el primer experimento se examinó el efecto del lavado de los espermatozoides. Para eso se substituyó tras el centrifugado el plasma seminal por solución Leibovitz. En el segundo experimento se examinó el efecto de la composición de los medios extensores en la calidad de los espermatozoides durante el almacenamiento. El medio extensor de solución Leibovitz se usó para lavar los espermatozoides. Para mejorar la composición del medio extensor, se prepararon soluciones agregando antioxidantes (BHT) y nutrientes (glutamina y glicina). En el tercer experimento, para mejorar la recolección de esperma, los gametos se recolectaron directamente en una jeringa que contenía el medio extensor Leibovitz. Los parámetros de calidad como el porcentaje de motilidad, las concentraciones de trifosfato de adenosina (ATP) y peroxidación lipídica en forma de malondialdehído (MDA) se midieron en relación con el tiempo de almacenamiento en los diferentes tratamientos. En el primer experimento, efecto del lavado en la calidad del esperma, los resultados muestran que los tratamientos de lavado con solución Leibovitz una sola vez (D-1C) y diluido (D) no tienen diferencias significativas entre ellos, y que ambos tratamientos tiene un efecto significativo respecto al tratamiento de lavado dos veces (D-2C). El mejor resultado en cuanto al mantenimiento de la motilidad por mayor tiempo (24h) f, [EN] Solea senegalensis, exhibits reproductive dysfunctions in captivity that limit production. The wild and F1 males produce little semen volume and the time of extraction of the gametes it is inevitable that the sperm is contaminated with urine causing the quality of the sperm to rapidly decrease making storage difficult. The objective of this study was to improve semen collection and protocols for short term refrigerated storage of sperm from Solea senegalensis. Samples from 41 males were examined in total, divided into 3 experiments. In the first experiment the effect of sperm washing was examined, in the second experiment the effect of the composition of the extender media on the quality of the sperm during storage was examined. Leibovitz solution extender medium was used to wash sperm. To improve the composition of the extensor medium, solutions were prepared with antioxidants (BHT) and nutrients (glutamine and glycine). In the third experiment, to improve sperm collection, the gametes were collected directly in a syringe containing Leibovitz extender medium and the quality of the sperm was compared with the gametes collected without extender. Quality parameters such as motility percentage, concentrations of adenosine triphosphate (ATP) and lipid peroxidation in the form of malondialdehyde (MDA) were measured in relation to storage time in the different treatments. In the first experiment, effect of washing on sperm quality, the results show that washing treatments with Leibovitz solution once (D-1C) and diluted (D) have no significant differences between them, and that these two treatments have a significant effect on the wash twice treatment (D-2C). The best result of maintaining motility for a longer time (24h) was the dilute treatment (D), and the wash once treatment (D-1C) had the best curvilinear speed (VCL) at 24h. In the second experiment, composition of the extender media and its effect on sperm quality during storage, significant differences were fou more...

[ES] Solea senegalensis, exhibe disfunciones reproductivas en cautiverio que limitan la producción. Los machos salvajes y F1 producen poco volumen de semen y al momento de extracción de gametos es casi inevitable la contaminación del esperma con orina, haciendo que la calidad de los espermatozoides disminuya rápidamente. Esto conlleva a que sea dificultoso el almacenamiento. El objetivo del presente estudio fue mejorar la recolección de semen y los protocolos para el almacenamiento corto refrigerado de esperma de Solea senegalensis. Se examinaron muestras de 41 machos en total divididas en 3 experimentos. En el primer experimento se examinó el efecto del lavado de los espermatozoides. Para eso se substituyó tras el centrifugado el plasma seminal por solución Leibovitz. En el segundo experimento se examinó el efecto de la composición de los medios extensores en la calidad de los espermatozoides durante el almacenamiento. El medio extensor de solución Leibovitz se usó para lavar los espermatozoides. Para mejorar la composición del medio extensor, se prepararon soluciones agregando antioxidantes (BHT) y nutrientes (glutamina y glicina). En el tercer experimento, para mejorar la recolección de esperma, los gametos se recolectaron directamente en una jeringa que contenía el medio extensor Leibovitz. Los parámetros de calidad como el porcentaje de motilidad, las concentraciones de trifosfato de adenosina (ATP) y peroxidación lipídica en forma de malondialdehído (MDA) se midieron en relación con el tiempo de almacenamiento en los diferentes tratamientos. En el primer experimento, efecto del lavado en la calidad del esperma, los resultados muestran que los tratamientos de lavado con solución Leibovitz una sola vez (D-1C) y diluido (D) no tienen diferencias significativas entre ellos, y que ambos tratamientos tiene un efecto significativo respecto al tratamiento de lavado dos veces (D-2C). El mejor resultado en cuanto al mantenimiento de la motilidad por mayor tiempo (24h) f, [EN] Solea senegalensis, exhibits reproductive dysfunctions in captivity that limit production. The wild and F1 males produce little semen volume and the time of extraction of the gametes it is inevitable that the sperm is contaminated with urine causing the quality of the sperm to rapidly decrease making storage difficult. The objective of this study was to improve semen collection and protocols for short term refrigerated storage of sperm from Solea senegalensis. Samples from 41 males were examined in total, divided into 3 experiments. In the first experiment the effect of sperm washing was examined, in the second experiment the effect of the composition of the extender media on the quality of the sperm during storage was examined. Leibovitz solution extender medium was used to wash sperm. To improve the composition of the extensor medium, solutions were prepared with antioxidants (BHT) and nutrients (glutamine and glycine). In the third experiment, to improve sperm collection, the gametes were collected directly in a syringe containing Leibovitz extender medium and the quality of the sperm was compared with the gametes collected without extender. Quality parameters such as motility percentage, concentrations of adenosine triphosphate (ATP) and lipid peroxidation in the form of malondialdehyde (MDA) were measured in relation to storage time in the different treatments. In the first experiment, effect of washing on sperm quality, the results show that washing treatments with Leibovitz solution once (D-1C) and diluted (D) have no significant differences between them, and that these two treatments have a significant effect on the wash twice treatment (D-2C). The best result of maintaining motility for a longer time (24h) was the dilute treatment (D), and the wash once treatment (D-1C) had the best curvilinear speed (VCL) at 24h. In the second experiment, composition of the extender media and its effect on sperm quality during storage, significant differences were fou more...

M&A scholars have generally assumed that post-acquisition integration is a self-contained process. However this ignores that this process rarely unfolds as the only ongoing initiative in an organization. We contend that post-acquisition integration is not detached from other simultaneous change processes in the organizational context and this has important implications for our understanding of how integration dynamics actually evolve. To further understand this embeddedness we examine the unfolding of a post-acquisition integration process in a company faced with an unanticipated drop in demand due to the global economic crisis. Through a qualitative, longitudinal study conducted over three years, we carried out 151 interviews to uncover the unfolding of the post-acquisition process. We find that post-acquisition integration is embedded in a set of co-evolving processes. We highlight four mechanisms (coordination, cohesion, disconnection, alienation) that arise from the co-evolution of processes that either facilitate or impede integration. Our findings contribute to our understanding of post-acquisition integration dynamics by recasting the integration process as embedded in a set of co-evolving processes that shape its unfolding. more...

Aim of study: The reproductive performance over a five year period in three different sole broodstocks: wild males with cultured females (WM), cultured males with wild females (CM), and a control of cultured males and females (C). Area of study: Cantabria, Northern Spain. Material and methods: The parental contribution was evaluated through the allocation of hatched larvae and a behavioural study was performed using underwater video recordings. Main results: Fertilized natural spawns were only obtained from group WM showing a significantly higher mean annual volume of floating eggs compared with groups CM and C. Over the entire 5-yr a higher number of spawns, total and floating volumes of eggs were obtained compared with groups CM and C. The analysis of four polymorphic microsatellites enabled the identification of the individuals involved in the fertile spawns by parental assignment. The percentage of individuals contributing to spawns ranged between 56.3% and 75% showing fidelity patterns. However between 46.2% and 68.6% of the contribution to production was a result of the crossing of three single couples. According to the behaviour analysis, group WM presented the highest peak of activity at 20:00 h and a higher activity profile during the night, moreover, the courtship behaviours “swim follow” and “swim followed”, were only recorded in group WM. Research highlights: The study has importance for aquaculture as it demonstrated how broodstocks with wild males and cultured females had adequate egg production for a commercial operation to supply eggs and implement single sex breeding programs more...

This chapter provides a state-of-the-art review of sole reproduction including the anatomy, morphology and maturation of the gonads, the annual reproductive cycles, the endocrinology of reproduction and the hormonal stimulation of reproduction. It provides work on both sole species, but especially on the Senegalese sole that has received a far greater research effort, as it has become the favoured species for aquaculture development due to better growth rates compared to common sole and perhaps a greater industrial interest in sole culture in the Iberian Peninsula. Galanin is a neuropeptide that mediates multiple physiological processes in vertebrates, including learning, food intake and reproduction. Consistent with the suggestion that differences between Senegalese sole wild and cultured broodstock are related to cultured male behavioural dysfunctions, is the observation that cultured broodstocks produce viable gametes. Under natural photoperiod and temperature, spawning and egg collection from broodstocks is highly seasonal in both sole species. more...

This chapter describes the successful mating behaviour of wild fish held in captivity. It examines the unsuccessful mating behaviour of hatchery fish and discusses the cause of the reproductive behavioural dysfunction and future research aims. Unsuccessful mating behaviour was studied in a broodstock of hatchery Senegalese sole that infrequently liberated eggs that were not viable when collected. The hormones used are applied to induce the final stages of maturation and in many examples also induce mating behaviour with successful spontaneous spawning. To differentiate between the behavioural capacities of hatchery males and females, experiments were undertaken that mixed the sexes by origin of wild or hatchery. Genes capture instinctive or innate behaviours that are required for the survival of the species and provide a structure to adjust and learn behaviours in response to the changing environment. A reproductive behavioural dysfunction in hatchery males is responsible for the failure to produce viable eggs from stocks hatched and reared in captivity. more...

M&A scholars have generally assumed that post-acquisition integration is a self-contained process. However this ignores that this process rarely unfolds as the only ongoing initiative in an organization. We contend that post-acquisition integration is not detached from other simultaneous change processes in the organizational context and this has important implications for our understanding of how integration dynamics actually evolve. To further understand this embeddedness we examine the unfolding of a post-acquisition integration process in a company faced with an unanticipated drop in demand due to the global economic crisis. Through a qualitative, longitudinal study conducted over three years, we carried out 151 interviews to uncover the unfolding of the post-acquisition process. We find that post-acquisition integration is embedded in a set of co-evolving processes. We highlight four mechanisms (coordination, cohesion, disconnection, alienation) that arise from the co-evolution of processes that either facilitate or impede integration. Our findings contribute to our understanding of post-acquisition integration dynamics by recasting the integration process as embedded in a set of co-evolving processes that shape its unfolding. more...

This publication is a simulation or game to be used in conjunction with a classroom experience. It is based on a real international Mergers and Acquisition (M&A) transaction involving a multi- billion dollar acquirer seeking to expand for the first time internationally. The simulation allows participants to experience the whole M&A process for themselves in the classroom – including triumphs and setbacks. The simulation will allow participants to gain insights into acquisition strategy, due diligence, company valuation, deal negotiations, contract design, post acquisition integration and performance outcomes. more...

Organisational leaders need to reach out to a variety of stakeholders in order to convey their strategic intent. Bridging these interfaces is a challenge that focuses attention on how strategy may be communicated effectively. Many authors advocate developing and communicating strategy using multi-media forms that combine words and pictures. However, there is little evidence that multi-media communication of strategy is increasing in practice. This raises the question of whether multi-media communication is indeed better than single media for strategy communications. Drawing upon the Cognitive Theory of Multimedia Learning we developed a series of hypotheses to find out, to what extent, and why, picture-plus-text presentation may provide greater benefits than text-only presentation in terms of 1) learning effectiveness, 2) perceptions of systematic integration, and 3) confidence building. To test whether multimedia strategy communications may provide more benefits than mono-media communications we ran an experiment across 8 countries involving 1,140 participants. Our results show there can be benefits to using multi-media means for strategy communications although there are performance variations that may determine when multi-media strategy communications are used in preference to mono-media means. These findings add to our understanding of the benefits and costs of multimedia strategy communications. more...

Purpose: Whilst substantial evidence from low corruption, developed market environments supports the view that more productive firms are more likely to export, there has been little research into analysing the link between productivity and exports in high corruption, developing market environments. The purpose of this paper is twofold. First, to test the premise of self-selection theory whether the association between productivity and export is maintained in high corruption environments, and second to identify other variables explaining export activity in high corruption contexts, including cluster networks and firms’ competences. Design/methodology/approach: The authors draw on the World Bank Enterprise survey to undertake a cross-section analysis including 1,233 SMEs located in nine African countries. The advantage of this database is that it contains information about the level of perceived corruption at firm-level. Logistic regressions are performed for the full sample and for subsamples of firms in high and low corruption environments. Findings: The findings demonstrate that the self-selection theory only applies to low corruption environments, whereas in high corruption environments, alternative factors such as cluster networks and outward looking competences, exert a stronger influence on the exporting activity of African SMEs. Research implications/limitations: This research contributes to theory as it provides evidence that contradicts the validity of self-selection theory in high corruption environments. Our findings would benefit from further longitudinal investigation. Practical implications: African SMEs need to consider cluster networks and outward looking competences as important strategic factors that might enhance their international competitiveness. Originality/value: Our criticism of the self-selection theory is distinctive in the literature and has important implications for future research. We show that the contextualisation of existing theories more...

Prior research on acquisition implementation has emphasized the challenge of balancing integration and autonomy (Graebner 2004). However, recent work has also emphasized the need to better distinguish integration and autonomy as two distinct dimensions of post acquisition implementation (Zaheer, Castañer et al. 2013). Moreover, there have been repeated calls to better understand what is really going on during the post-acquisition implementation process, contingent on the type of post-acquisition mode (Graebner, Heimeriks et al. 2017). The typology of post-acquisition modes presented by Haspelagh and Jemison (1991) focuses on the managerial actions and the transfer of capabilities between the acquiring parent and the acquired target through mechanisms of resource sharing, functional skills transfer, and general management capability. Alongside this strategic task of transferring capabilities to create value, the degree of organizational autonomy granted to the target reflects a concern for protecting the target’s strategic capabilities which have motivated the acquisition in the first place. Yet, the implicit result from this sequential approach advocated by the existing literature is that full integration will eventually occur and lead to the amalgamation of the target into the parent company. However if the acquisition is in a poor state or there is reason not to fully integrate, then how do the integration and autonomy dynamics interact over time? How can a poor performance target ever regain autonomy and escape amalgamation? more...

Prior research on acquisition implementation has emphasized the challenge of balancing integration and autonomy (Graebner 2004). However, recent work has also emphasized the need to better distinguish integration and autonomy as two distinct dimensions of post acquisition implementation (Zaheer, Castañer et al. 2013). Moreover, there have been repeated calls to better understand what is really going on during the post-acquisition implementation process, contingent on the type of post-acquisition mode (Graebner, Heimeriks et al. 2017). The typology of post-acquisition modes presented by Haspelagh and Jemison (1991) focuses on the managerial actions and the transfer of capabilities between the acquiring parent and the acquired target through mechanisms of resource sharing, functional skills transfer, and general management capability. Alongside this strategic task of transferring capabilities to create value, the degree of organizational autonomy granted to the target reflects a concern for protecting the target’s strategic capabilities which have motivated the acquisition in the first place. Yet, the implicit result from this sequential approach advocated by the existing literature is that full integration will eventually occur and lead to the amalgamation of the target into the parent company. However if the acquisition is in a poor state or there is reason not to fully integrate, then how do the integration and autonomy dynamics interact over time? How can a poor performance target ever regain autonomy and escape amalgamation? more...

This publication is a simulation or game to be used in conjunction with a classroom experience. It is based on a real international Mergers and Acquisition (M&A) transaction involving a multi- billion dollar acquirer seeking to expand for the first time internationally. The simulation allows participants to experience the whole M&A process for themselves in the classroom – including triumphs and setbacks. The simulation will allow participants to gain insights into acquisition strategy, due diligence, company valuation, deal negotiations, contract design, post acquisition integration and performance outcomes. more...

Organisational leaders need to reach out to a variety of stakeholders in order to convey their strategic intent. Bridging these interfaces is a challenge that focuses attention on how strategy may be communicated effectively. Many authors advocate developing and communicating strategy using multi-media forms that combine words and pictures. However, there is little evidence that multi-media communication of strategy is increasing in practice. This raises the question of whether multi-media communication is indeed better than single media for strategy communications. Drawing upon the Cognitive Theory of Multimedia Learning we developed a series of hypotheses to find out, to what extent, and why, picture-plus-text presentation may provide greater benefits than text-only presentation in terms of 1) learning effectiveness, 2) perceptions of systematic integration, and 3) confidence building. To test whether multimedia strategy communications may provide more benefits than mono-media communications we ran an experiment across 8 countries involving 1,140 participants. Our results show there can be benefits to using multi-media means for strategy communications although there are performance variations that may determine when multi-media strategy communications are used in preference to mono-media means. These findings add to our understanding of the benefits and costs of multimedia strategy communications. more...

Purpose: Whilst substantial evidence from low corruption, developed market environments supports the view that more productive firms are more likely to export, there has been little research into analysing the link between productivity and exports in high corruption, developing market environments. The purpose of this paper is twofold. First, to test the premise of self-selection theory whether the association between productivity and export is maintained in high corruption environments, and second to identify other variables explaining export activity in high corruption contexts, including cluster networks and firms’ competences. Design/methodology/approach: The authors draw on the World Bank Enterprise survey to undertake a cross-section analysis including 1,233 SMEs located in nine African countries. The advantage of this database is that it contains information about the level of perceived corruption at firm-level. Logistic regressions are performed for the full sample and for subsamples of firms in high and low corruption environments. Findings: The findings demonstrate that the self-selection theory only applies to low corruption environments, whereas in high corruption environments, alternative factors such as cluster networks and outward looking competences, exert a stronger influence on the exporting activity of African SMEs. Research implications/limitations: This research contributes to theory as it provides evidence that contradicts the validity of self-selection theory in high corruption environments. Our findings would benefit from further longitudinal investigation. Practical implications: African SMEs need to consider cluster networks and outward looking competences as important strategic factors that might enhance their international competitiveness. Originality/value: Our criticism of the self-selection theory is distinctive in the literature and has important implications for future research. We show that the contextualisation of existing theories more...

[EN] This article reviews the use of hormonal treatments to enhance sperm production in aquaculture fish and the methods available for evaluating sperm quality. The different types of testis development are examined and a brief review is presented of the endocrine regulation of spermatogenesis in fishes, including the increasing evidence of the existence of spermatozoa subpopulations. Hormonal manipulations are employed to induce spermatogenesis in species such as the freshwater eels, to synchronize maximal sperm volume to ovulation for in vitro fertilization and to enhance sperm production in species with poor spermiation. The hormones that are employed include gonadotropins (GtHs) of piscine or mammalian origin, and gonadotropin-releasing hormone agonists (GnRHa) administered by injections or controlled-release delivery systems, with or without dopaminergic inhibitors. Pheromones in the culture water and hormones added to the sperm in vitro have also been employed to enhance spermiation and sperm quality, respectively, in some fishes. Hormonal therapies usually do not affect sperm quality parameters, except in cases where fish fail to spermiate naturally or produce very small volumes of high-density sperm. Different parameters have been used to evaluate fish sperm quality, including sperm volume and density, spermatozoa motility and morphometry, and seminal plasma composition. The development of Computer-Assisted Sperm Analysis (CASA) systems made possible the estimation of a higher number of sperm motion parameters using an objective, sensitive and accurate technique. The development of Assisted Sperm Morphology Analysis (ASMA) software has introduced a new approach for sperm evaluation studies, demonstrating changes in the spermatozoa related to reproductive season, hormonal treatments or the cryopreservation processes, and how these may be related to changes in sperm motility and fertilization capacity. The article concludes with a few practical protocols for t more...

[EN] This article reviews the use of hormonal treatments to enhance sperm production in aquaculture fish and the methods available for evaluating sperm quality. The different types of testis development are examined and a brief review is presented of the endocrine regulation of spermatogenesis in fishes, including the increasing evidence of the existence of spermatozoa subpopulations. Hormonal manipulations are employed to induce spermatogenesis in species such as the freshwater eels, to synchronize maximal sperm volume to ovulation for in vitro fertilization and to enhance sperm production in species with poor spermiation. The hormones that are employed include gonadotropins (GtHs) of piscine or mammalian origin, and gonadotropin-releasing hormone agonists (GnRHa) administered by injections or controlled-release delivery systems, with or without dopaminergic inhibitors. Pheromones in the culture water and hormones added to the sperm in vitro have also been employed to enhance spermiation and sperm quality, respectively, in some fishes. Hormonal therapies usually do not affect sperm quality parameters, except in cases where fish fail to spermiate naturally or produce very small volumes of high-density sperm. Different parameters have been used to evaluate fish sperm quality, including sperm volume and density, spermatozoa motility and morphometry, and seminal plasma composition. The development of Computer-Assisted Sperm Analysis (CASA) systems made possible the estimation of a higher number of sperm motion parameters using an objective, sensitive and accurate technique. The development of Assisted Sperm Morphology Analysis (ASMA) software has introduced a new approach for sperm evaluation studies, demonstrating changes in the spermatozoa related to reproductive season, hormonal treatments or the cryopreservation processes, and how these may be related to changes in sperm motility and fertilization capacity. The article concludes with a few practical protocols for t more...

Tesis por compendio, Senegalese sole is a flatfish species with increasing importance for the aquaculture industry due to its good performance (survival and growth) in captivity and high market price.However,one of the principal bottlenecks to the expansion of the species culture is the reproductive behavioural dysfunction in cultured males,which complicates establishing a closed cycle in captivity.The reproductive behavioural dysfunction is exhibited by the cultured males that do not participate in the courtship.Therefore, Senegalese sole production relies on wild males,which is unsustainable in the long term.With the aim to understand and look for solutions to this bottleneck,the present thesis focuses on different aspects of behaviour related to reproduction and the olfactory system. The effect of the presence of spawning wild Senegalese sole breeders on the reproductive behaviour and reproductive success of cohabiting cultured breeders was examined.Three groups were established,1 formed by cultures sole and 2 mixed groups (cultured and wild).Fertilised spawns were not obtained from the control group.However,fertilised spawns were obtained from the mixed-origin groups.Cultured males were observed to participate increasingly in the courtship and one cultured male fertilised 2 spawns.These results suggested a learning process in this species for behaviours associated to reproduction.With the olfactory analysis,the structure of the olfactory rosettes of 2 groups from different origin of Senegalese sole juveniles were compared.No significant differences in tissue structure,cell types and cellular distribution pattern were observed between origin specimens,however,differences were found between rosettes in number of lamellae and amount of goblet cells in the ridge region of the lamella,which were more frequent in the lower rosette.Related to the comparison of transcriptomic profiles (RNA-seq) of the upper rosette in cultured and wild sole mature males,the difference in transcripts of some, El lenguado Senegalés es una especie de pez plano que está en constante crecimiento de producción dentro de la industria de la acuicultura debido a su buena capacidad de supervivencia y crecimiento en cautividad,además de poseer un elevado precio en el mercado.En cambio,uno de los principales problemas de expansión del cultivo del lenguado es la disfunción reproductiva asociada al comportamiento complicando el cierre del ciclo de vida de esta especie en cautividad.La disfunción reproductiva se ve en los machos de cultivo que no participan en el cortejo.Consecuentemente,la producción del lenguado recae en los machos salvajes siendo insostenible a largo plazo.Esta tesis tiene como objetivo principal entender y buscar posibles soluciones a este problema enfocándose en diferentes aspectos relacionados con la reproducción y el sistema olfativo.Primero se realizó un análisis de efecto de la presencia de lenguados salvajes que se reproducen,en el cortejo y el éxito reproductivo de los lenguados de cultivo,que no se reproducen.Se formaron 3 grupos,1 de cultivo (control) y 2 mezcla (cultivo y salvajes).No se obtuvo puestas fecundadas del grupo control,en cabio si se obtuvo de los grupos mezcla,viendose por primera vez un aumento de participación de los machos de cultivo,donde un macho de cultivo fertilizó 2 puestas.Estos resultados sugieren un posible proceso de aprendizaje del cortejo por parte de los machos de cultivo.Con el análisis del olfato,primero se realizó una descripción y comparación histológica de la estructura de ambas rosetas olfativas de dos grupos de lenguados juveniles (cultivo y salvaje).No se hallaron diferencias significativas en la estructura tisular, tipos de células y distribución celular entre lenguados de diferente origen, en cambio, se encontraron diferencias entre las rosetas en número total de lamelas y en cantidad de células goblet concentradas en la parte apical de las lamelas siendo más frecuente en la roseta inferior.Con referencia a la compar, El llenguado Senegalès es una espècie de peix pla que està en constant creixement de producció dins de la industria de l'aqüicultura degut a la seua capacitat de supervivència i creixement en captivitat,a més de posseir un elevat preu al mercat.En canvi,un dels principals problemes d'expansió del cultiu d'aquesta espècie és la disfunció reproductiva associada al comportament que complica tancar el cicle de vida del llenguado en captivitat.La disfunció reproductiva s'observa als mascles de cultiu que no participen al seguici.Conseqüentment,la producció del llenguado Senegalès depèn dels mascles salvatges el qual es insostenible a llarg termini.Esta tesi té com objectiu principal entendre i buscar possibles solucions a aquest problema enfocant-se en diferents aspectes relacionats amb la reproducció i el sistema olfactiu.Primer es realitzà un anàlisi d'efecte de la presència de llenguados salvatges que es reprodueixen en el seguici i l'èxit reproductiu dels llenguados de cultiu que no es reprodueixen.Es formà 3 grups,un de cultiu (control) i 2 mescla (cultiu i salvatges).No s'obtingué posts fecundades del grup control,en canvi si s'obtingueren dels grups mescla,veient un augment de participació dels mascles de cultiu per primera volta,on un mascle de cultiu va fertilitzar 2 postes.Aquests resultats suggereixen un procés d'aprenentatge del seguici per part dels mascles de cultiu.Amb l'anàlisi de l'olfacte,primer es realitzà una descripció i comparació estructural histològica de ambdues rosetes olfactives de 2 grups de llenguados juvenils dels dos orígens.No es trobà diferències en l'estructura tissular,tipus de cèl·lules i distribució entre llenguados de diferent origen,en canvi,es trobà diferències entre rosetes en nombre total de lamel·les i quantitat de cèl·lules goblet concentrades a la part apical de la lamel·la més freqüents a la roseta inferior.En referència a la comparació transcriptómica (RNA-seq) de la roseta superior en mascles madurs salvatges i de cultiu,es more...

Tesis por compendio, Senegalese sole is a flatfish species with increasing importance for the aquaculture industry due to its good performance (survival and growth) in captivity and high market price.However,one of the principal bottlenecks to the expansion of the species culture is the reproductive behavioural dysfunction in cultured males,which complicates establishing a closed cycle in captivity.The reproductive behavioural dysfunction is exhibited by the cultured males that do not participate in the courtship.Therefore, Senegalese sole production relies on wild males,which is unsustainable in the long term.With the aim to understand and look for solutions to this bottleneck,the present thesis focuses on different aspects of behaviour related to reproduction and the olfactory system. The effect of the presence of spawning wild Senegalese sole breeders on the reproductive behaviour and reproductive success of cohabiting cultured breeders was examined.Three groups were established,1 formed by cultures sole and 2 mixed groups (cultured and wild).Fertilised spawns were not obtained from the control group.However,fertilised spawns were obtained from the mixed-origin groups.Cultured males were observed to participate increasingly in the courtship and one cultured male fertilised 2 spawns.These results suggested a learning process in this species for behaviours associated to reproduction.With the olfactory analysis,the structure of the olfactory rosettes of 2 groups from different origin of Senegalese sole juveniles were compared.No significant differences in tissue structure,cell types and cellular distribution pattern were observed between origin specimens,however,differences were found between rosettes in number of lamellae and amount of goblet cells in the ridge region of the lamella,which were more frequent in the lower rosette.Related to the comparison of transcriptomic profiles (RNA-seq) of the upper rosette in cultured and wild sole mature males,the difference in transcripts of some, El lenguado Senegalés es una especie de pez plano que está en constante crecimiento de producción dentro de la industria de la acuicultura debido a su buena capacidad de supervivencia y crecimiento en cautividad,además de poseer un elevado precio en el mercado.En cambio,uno de los principales problemas de expansión del cultivo del lenguado es la disfunción reproductiva asociada al comportamiento complicando el cierre del ciclo de vida de esta especie en cautividad.La disfunción reproductiva se ve en los machos de cultivo que no participan en el cortejo.Consecuentemente,la producción del lenguado recae en los machos salvajes siendo insostenible a largo plazo.Esta tesis tiene como objetivo principal entender y buscar posibles soluciones a este problema enfocándose en diferentes aspectos relacionados con la reproducción y el sistema olfativo.Primero se realizó un análisis de efecto de la presencia de lenguados salvajes que se reproducen,en el cortejo y el éxito reproductivo de los lenguados de cultivo,que no se reproducen.Se formaron 3 grupos,1 de cultivo (control) y 2 mezcla (cultivo y salvajes).No se obtuvo puestas fecundadas del grupo control,en cabio si se obtuvo de los grupos mezcla,viendose por primera vez un aumento de participación de los machos de cultivo,donde un macho de cultivo fertilizó 2 puestas.Estos resultados sugieren un posible proceso de aprendizaje del cortejo por parte de los machos de cultivo.Con el análisis del olfato,primero se realizó una descripción y comparación histológica de la estructura de ambas rosetas olfativas de dos grupos de lenguados juveniles (cultivo y salvaje).No se hallaron diferencias significativas en la estructura tisular, tipos de células y distribución celular entre lenguados de diferente origen, en cambio, se encontraron diferencias entre las rosetas en número total de lamelas y en cantidad de células goblet concentradas en la parte apical de las lamelas siendo más frecuente en la roseta inferior.Con referencia a la compar, El llenguado Senegalès es una espècie de peix pla que està en constant creixement de producció dins de la industria de l'aqüicultura degut a la seua capacitat de supervivència i creixement en captivitat,a més de posseir un elevat preu al mercat.En canvi,un dels principals problemes d'expansió del cultiu d'aquesta espècie és la disfunció reproductiva associada al comportament que complica tancar el cicle de vida del llenguado en captivitat.La disfunció reproductiva s'observa als mascles de cultiu que no participen al seguici.Conseqüentment,la producció del llenguado Senegalès depèn dels mascles salvatges el qual es insostenible a llarg termini.Esta tesi té com objectiu principal entendre i buscar possibles solucions a aquest problema enfocant-se en diferents aspectes relacionats amb la reproducció i el sistema olfactiu.Primer es realitzà un anàlisi d'efecte de la presència de llenguados salvatges que es reprodueixen en el seguici i l'èxit reproductiu dels llenguados de cultiu que no es reprodueixen.Es formà 3 grups,un de cultiu (control) i 2 mescla (cultiu i salvatges).No s'obtingué posts fecundades del grup control,en canvi si s'obtingueren dels grups mescla,veient un augment de participació dels mascles de cultiu per primera volta,on un mascle de cultiu va fertilitzar 2 postes.Aquests resultats suggereixen un procés d'aprenentatge del seguici per part dels mascles de cultiu.Amb l'anàlisi de l'olfacte,primer es realitzà una descripció i comparació estructural histològica de ambdues rosetes olfactives de 2 grups de llenguados juvenils dels dos orígens.No es trobà diferències en l'estructura tissular,tipus de cèl·lules i distribució entre llenguados de diferent origen,en canvi,es trobà diferències entre rosetes en nombre total de lamel·les i quantitat de cèl·lules goblet concentrades a la part apical de la lamel·la més freqüents a la roseta inferior.En referència a la comparació transcriptómica (RNA-seq) de la roseta superior en mascles madurs salvatges i de cultiu,es more...

[EN] This article reviews the use of hormonal treatments to enhance sperm production in aquaculture fish and the methods available for evaluating sperm quality. The different types of testis development are examined and a brief review is presented of the endocrine regulation of spermatogenesis in fishes, including the increasing evidence of the existence of spermatozoa subpopulations. Hormonal manipulations are employed to induce spermatogenesis in species such as the freshwater eels, to synchronize maximal sperm volume to ovulation for in vitro fertilization and to enhance sperm production in species with poor spermiation. The hormones that are employed include gonadotropins (GtHs) of piscine or mammalian origin, and gonadotropin-releasing hormone agonists (GnRHa) administered by injections or controlled-release delivery systems, with or without dopaminergic inhibitors. Pheromones in the culture water and hormones added to the sperm in vitro have also been employed to enhance spermiation and sperm quality, respectively, in some fishes. Hormonal therapies usually do not affect sperm quality parameters, except in cases where fish fail to spermiate naturally or produce very small volumes of high-density sperm. Different parameters have been used to evaluate fish sperm quality, including sperm volume and density, spermatozoa motility and morphometry, and seminal plasma composition. The development of Computer-Assisted Sperm Analysis (CASA) systems made possible the estimation of a higher number of sperm motion parameters using an objective, sensitive and accurate technique. The development of Assisted Sperm Morphology Analysis (ASMA) software has introduced a new approach for sperm evaluation studies, demonstrating changes in the spermatozoa related to reproductive season, hormonal treatments or the cryopreservation processes, and how these may be related to changes in sperm motility and fertilization capacity. The article concludes with a few practical protocols for t more...

Many studies of M&A performance suggest that most fail, using a wide range of methods and criteria for evaluation but based on the general assumption that they aim to maximise value. M&A are also studied at different levels of analysis, notably from strategy, CEO and macro perspectives and yet performance studies have not yet integrated these in a single analysis. This paper draws upon these three levels to create an M&A typology that can then be tested using a CAAR methodology. Results indicate significant differences in performance by M&A type. This suggests that each of the levels of analysis matters and in particular that context plays a crucial role. Our evidence suggests that, contrary to current M&A performance dogma, M&As with a classical strategy and good agent CEO during a boom period, out perform the market and other M&A deals. more...

Little is known about routine interconnectedness and its temporal dimension, and yet, in fast changing environments, the dynamics of routine interaction may matter. In order to investigate this issue, this paper focuses upon routine transformation and their impact upon meta-routine outcome. This paper draws upon 3 longitudinal cases in a complex dynamic setting – post acquisition integration to explore routine combinations. Conceptualizing post acquisition integration as amalgamation of routines of two participating firms, we find that temporal nature of routines inhibit routines combinations and new routines in the form of connectors are required to restore the interconnectedness of the combined routine networks. This empirical study, in addition to advancing routines theory, opens up the black box of post acquisition integration by providing details of what actually happens during integrations. more...

Building on research focusing on endogenous routine dynamics, we aim to understand how routines need to be brought together to achieve synergies in the post-acquisition integration processes. Based on a, longitudinal case study of a consultancy sector acquisition in France,, we apply a practice-based lens to study the intended combination of two existing routines and why its implementation turned out to be a failure. Our findings suggest that seemingly matching routines were not compatible in practice as the underlying patterns of action could not be easily combined. Our article sheds light on the role of routines in M&A and contributes to the literature by discussing a) the prevailing role of the interconnectedness of routines in effective acquisition integration and capability transfer and b) discrepancies between ostensive and performative aspects of routines as impediments to the implementation of the pre-acquisition plan in the post-acquisition phase. 11.Mirc, N., Seles, K., Angwin, D. N. (2017) When matching routines meet– a routine dynamic perspective on post-acquisition integration, Strategic Management Society Special Conference, San Jose, Costa Rica, December. more...

Spatial interfaces provide the conditions that facilitate or constrain unplanned social interaction. Emergent strategy work is constituted by unintentional social interaction. This paper draws on two disparate literatures, strategy process and architecture, to argue that a possible relationship between spatial configuration and emergent strategy should be taken seriously. Strategy process research has shown that emergent strategy making is important to an organisation’s ability to innovate and adapt in dynamic environments, these abilities are associated with the frequency, diversity, duration and distribution of non-deliberate strategic interactions. Architecture research has shown that spatial configuration has a powerful affect on unplanned social interaction. Strategy-as-Practice, with its focus on social interaction, is proposed as the ideal perspective with which to investigate this possible relationship further. The research uses quantitative methods to explore the extent of the relationship between spatial configuration and the unplanned interactions that constitute emergent strategy making. The results suggest a strong relationship which when compared across four organisations imply very different opportunities for emergent strategy work in each and concludes that emergent strategy needs to be thought of as a material, spatial phenomenon and not just a conceptual one. more...

Strategy is a crucial subject. It’s about the overall direction of all kinds of organisations, from multinationals to entrepreneurial start-ups, from charities to government agencies, and many more. Strategy raises the big questions about these organisations – how they grow, how they innovate and how they change. As a manager of today or of tomorrow, you will be involved in shaping, implementing or communicating these strategies. Our aim in writing Fundamentals of Strategy is to give you a clear understanding of the fundamental issues and techniques of strategy, and to help you get a great final result in your course. Here’s how you might make the most of the text: Focus your time and attention on the fundamental areas of strategy in just eight carefully selected chapters. Read the illustrations and the case examples to clarify your understanding of how the concepts of strategy translate into an easily recognisable, real-world context. Follow up on the recommended key readings at the end of each chapter. They’re specially selected as accessible and valuable sources that will enhance your learning and give you an extra edge in your course work. more...

With over one million copies sold this is the biggest selling strategy text in Europe. It is an essential introduction to strategic management for students and an essential resource for practicing managers of all types of organisations. more...

Our study theorizes and tests why organizations engage in more external transparency as an open strategy practice and the share-price related outcomes associated with these practices. Drawing from literature on information asymmetry, we suggest that organizations that depart from their existing strategy or deviate from industry norms are more likely to open up their strategy in order to escape negative evaluations by analysts and scrutiny by investors. We further investigate how the stock market responds to more openness in strategy. In a dataset comprising of a sample of 472 M&A deals and 886 associated corporate voluntary communications over a five-year period, we find that the likelihood of organizations engaging in open strategy practices that contribute to external transparency is associated with the degree to which an organization’s strategy differs from industry norms, but is not associated with how much it varies from its existing one. Regarding organizational outcomes of increased openness in strategy, we illustrate that increasing the transparency of M&A strategy to investors through voluntary communications can bring share-price related benefits. Our research contributes to literature on open strategy, information asymmetry, and managing M&A. more...

Many studies of M&A performance suggest that most fail, using a wide range of methods and criteria for evaluation but based on the general assumption that they aim to maximise value. M&A are also studied at different levels of analysis, notably from strategy, CEO and macro perspectives and yet performance studies have not yet integrated these in a single analysis. This paper draws upon these three levels to create an M&A typology that can then be tested using a CAAR methodology. Results indicate significant differences in performance by M&A type. This suggests that each of the levels of analysis matters and in particular that context plays a crucial role. Our evidence suggests that, contrary to current M&A performance dogma, M&As with a classical strategy and good agent CEO during a boom period, out perform the market and other M&A deals. more...

Spatial interfaces provide the conditions that facilitate or constrain unplanned social interaction. Emergent strategy work is constituted by unintentional social interaction. This paper draws on two disparate literatures, strategy process and architecture, to argue that a possible relationship between spatial configuration and emergent strategy should be taken seriously. Strategy process research has shown that emergent strategy making is important to an organisation’s ability to innovate and adapt in dynamic environments, these abilities are associated with the frequency, diversity, duration and distribution of non-deliberate strategic interactions. Architecture research has shown that spatial configuration has a powerful affect on unplanned social interaction. Strategy-as-Practice, with its focus on social interaction, is proposed as the ideal perspective with which to investigate this possible relationship further. The research uses quantitative methods to explore the extent of the relationship between spatial configuration and the unplanned interactions that constitute emergent strategy making. The results suggest a strong relationship which when compared across four organisations imply very different opportunities for emergent strategy work in each and concludes that emergent strategy needs to be thought of as a material, spatial phenomenon and not just a conceptual one. more...

Little is known about routine interconnectedness and its temporal dimension, and yet, in fast changing environments, the dynamics of routine interaction may matter. In order to investigate this issue, this paper focuses upon routine transformation and their impact upon meta-routine outcome. This paper draws upon 3 longitudinal cases in a complex dynamic setting – post acquisition integration to explore routine combinations. Conceptualizing post acquisition integration as amalgamation of routines of two participating firms, we find that temporal nature of routines inhibit routines combinations and new routines in the form of connectors are required to restore the interconnectedness of the combined routine networks. This empirical study, in addition to advancing routines theory, opens up the black box of post acquisition integration by providing details of what actually happens during integrations. more...

Strategy is a crucial subject. It’s about the overall direction of all kinds of organisations, from multinationals to entrepreneurial start-ups, from charities to government agencies, and many more. Strategy raises the big questions about these organisations – how they grow, how they innovate and how they change. As a manager of today or of tomorrow, you will be involved in shaping, implementing or communicating these strategies. Our aim in writing Fundamentals of Strategy is to give you a clear understanding of the fundamental issues and techniques of strategy, and to help you get a great final result in your course. Here’s how you might make the most of the text: Focus your time and attention on the fundamental areas of strategy in just eight carefully selected chapters. Read the illustrations and the case examples to clarify your understanding of how the concepts of strategy translate into an easily recognisable, real-world context. Follow up on the recommended key readings at the end of each chapter. They’re specially selected as accessible and valuable sources that will enhance your learning and give you an extra edge in your course work. more...

Building on research focusing on endogenous routine dynamics, we aim to understand how routines need to be brought together to achieve synergies in the post-acquisition integration processes. Based on a, longitudinal case study of a consultancy sector acquisition in France,, we apply a practice-based lens to study the intended combination of two existing routines and why its implementation turned out to be a failure. Our findings suggest that seemingly matching routines were not compatible in practice as the underlying patterns of action could not be easily combined. Our article sheds light on the role of routines in M&A and contributes to the literature by discussing a) the prevailing role of the interconnectedness of routines in effective acquisition integration and capability transfer and b) discrepancies between ostensive and performative aspects of routines as impediments to the implementation of the pre-acquisition plan in the post-acquisition phase. 11.Mirc, N., Seles, K., Angwin, D. N. (2017) When matching routines meet– a routine dynamic perspective on post-acquisition integration, Strategic Management Society Special Conference, San Jose, Costa Rica, December. more...

Our study theorizes and tests why organizations engage in more external transparency as an open strategy practice and the share-price related outcomes associated with these practices. Drawing from literature on information asymmetry, we suggest that organizations that depart from their existing strategy or deviate from industry norms are more likely to open up their strategy in order to escape negative evaluations by analysts and scrutiny by investors. We further investigate how the stock market responds to more openness in strategy. In a dataset comprising of a sample of 472 M&A deals and 886 associated corporate voluntary communications over a five-year period, we find that the likelihood of organizations engaging in open strategy practices that contribute to external transparency is associated with the degree to which an organization’s strategy differs from industry norms, but is not associated with how much it varies from its existing one. Regarding organizational outcomes of increased openness in strategy, we illustrate that increasing the transparency of M&A strategy to investors through voluntary communications can bring share-price related benefits. Our research contributes to literature on open strategy, information asymmetry, and managing M&A. more...

With over one million copies sold this is the biggest selling strategy text in Europe. It is an essential introduction to strategic management for students and an essential resource for practicing managers of all types of organisations. more...

Chemical communication is better understood in freshwater fish than marine fish. The Senegalese sole (Solea senegalensis) is a marine flatfish wherein one of the problems in aquaculture is the poor reproductive performance of hatchery-bred males. Is chemical communication involved in the reproduction of this species Urine, intestinal fluid and mucus samples were taken from adult fish (wildcaught and hatchery-bred) over the spawning season (March-May), and assessed for olfactory potency using the electro-olfactogram (EOG). The effect of stimulation of the olfactory system with adult female urine on circulating luteinizing hormone (LH) levels was also tested in males. Intestinal fluid and urine were potent olfactory stimuli for both juvenile and adult conspecifics, evoking large-amplitude, concentration-dependent EOG responses, with thresholds of detection at approximately 1:106. However, the amplitude of the response to urine depended on the sex and state of maturity of both the donor and the receiver. Most olfactory activity could be extracted by C18 solid-phase cartridges. Urine from mature females evoked a slight, but significant, increase in circulating LH levels in mature males 30 min after exposure. Furthermore, the olfactory potency of urine differed between wild-caught and hatchery-bred fish; however, contrary to expectations, urine from wild-caught females was less potent than that from hatchery-bred females. Taken together, these results strongly suggest that faeces-and urine-released odorants are involved in reproduction in the Senegalese sole, and establish a basis for further investigation into pheromonal communication in marine teleosts more...

Captive flatfishes, such as the Senegalese sole, typically produce very low volumes of sperm. This situation is particularly prevalent in the first generation (F1) of reared sole males, which limits the development of artificial fertilization methods and the implementation of selective breeding programs. In this study, we investigated whether combined treatments with homologous recombinant follicle-stimulating (rFsh) and luteinizing (rLh) hormones, produced in a mammalian host system, could stimulate spermatogenesis and enhance sperm production in Senegalese sole F1 males. In an initial autumn/winter experiment, weekly intramuscular injections with increasing doses of rFsh over 9 weeks resulted in the stimulation of gonad weight, androgen release, germ cell proliferation and entry into meiosis, and the expression of different spermatogenesis-related genes, whereas a subsequent single rLh injection potentiated spermatozoa differentiation. In a second late winter/spring trial corresponding to the sole’s natural prespawning and spawning periods, we tested the effect of repeated rLh injections on the amount and quality of sperm produced by males previously treated with rFsh for 4, 6, 8 or 10 weeks. These latter results showed that the combination of rFsh and rLh treatments could increase sperm production up to 7 times, and slightly improve the motility of the spermatozoa, although a high variability in the response was found. However, sustained administration of rFsh during spawning markedly diminished Leydig cell survival and the steroidogenic potential of the testis. These data suggest that in vivo application of rFsh and rLh is effective at stimulating spermatogenesis and sperm production in Senegalese sole F1 males, setting the basis for the future establishment of recombinant gonadotropin-based hormone therapies to ameliorate reproductive dysfunctions of this species more...

Senegalese sole (Solea senegalensis) have a high potential for aquaculture that is hampered by reproductive behavioural problems. These problems result in limited breeder participation in spawning. The present study provided an ethogram and described mate selection and spawning of captive wild Senegalese sole. Two tanks of breeders were studied that had 29 and 25 breeders (mean weight = 1.6 ± 0.1 kg). The behaviour was studied during 20 periods of 24 hours: 10 periods where spawning events were recorded and 10 control periods without spawning events. Periods where spawning occurred had three times more locomotor activity than periods without spawning. Two distinct behaviours, termed the “following” behaviour and the “coupled swim”, were only observed during periods with spawning. The courtship sequence (n=12) began with males predominantly involved in “following” behaviours, whilst females remained mainly stationary on the bottom of the tank. Males rested on the females and encouraged the females to begin swimming. When the female began to swim the male swam under the female and the pair made a “coupled swim” to the surface to release gametes. Gamete release was strictly in pairs of one male with one female. Failed “coupled swims” without gamete release were 5.6 times more frequent than successful “coupled swims”. Mate selection was evident as the sole engaged in: paired spawning, males displayed to females, males encouraged females to spawn and females accepted or rejected the male’s advances. The mate selection process provided the opportunity for fish to dominate the spawning and also demonstrated how fish were excluded from spawning. more...