Loading...
12 results
Search Results
Now showing 1 - 10 of 12
- Effects of phylloquinone on Solea senegalensis skeletogenesisPublication . Gavaia, Paulo J.; Dionísio, Gisela; Conceição, L. E. C.; Hamre, K.; Cancela, LeonorSkeletogenesis is a continuous process occurring during fish larval development that is influenced by vitamin K VK, an essential factor for the correct formation of coagulation factors and skeletal matrix proteins. High levels of skeletal deformities are recorded in most commonly cultured species like the sparids, sea bass and flatfish like the Senegalese sole. The appearance of malformations takes place during the larval stages, when skeletal structures are forming.
- Diets affect skeletal development in zebrafish (Danio rerio)Publication . Dionísio, Gisela; Brito, A. B.; Cancela, Leonor; Gavaia, Paulo J.The zebrafish Danio rerio has recently emerged as an eminent vertebrate model for studyign genetics and development. Given the considerable importance of zebrafish as an experimental model, along with the significant economic costs associated with their large-scale use and maintenance of culturing facilities, it is to some extent surprising that their husbandry is poorly developed.
- Early axial and appendicular skeletal development of the meagre (Argyrosomus regius). A comparison of two rearing systemsPublication . Valles, E.; Cardeira Da Silva, João; Dionísio, Gisela; Estévez, A.; Pousão-Ferreira, P.; Cancela, Leonor; Gavaia, Paulo J.The meagre (Argyrosomus regius) is a new species for aquaculture with high economical value, presenting growth rates of 1 kg/year. Skeletal deformities generally appear in cultured larvae at early stages, reducing the value of the fish. The present study describes the osteological development of the vertebral column and fins in meagre larvae. Meagre larvae were obtained from wild broodstocks, kept at IRTA and IPIMAR, and induced to spawn using GnRHa injection.
- Effect of egg incubation temperature on the occurrence of skeletal deformities in Solea senegalensisPublication . Dionísio, Gisela; Campos, C.; Valente, L. M. P.; Conceição, L. E. C.; Cancela, Leonor; Gavaia, Paulo J.Temperature is a factor known to have a marked influence on metabolism and consequently on development, inducing ontogenetic plasticity in fish larvae. In this study, three different temperatures (15, 18 and 21 C) were assayed during Solea senegalensis embryonic development prior to hatching. After hatching all larvae were reared at the same temperature (21.0 ± 0.1 C) until 30 days. We observed that lowering the incubation temperature from 21 to 15 C reduced the incidence of skeletal deformities from 80 to 60%. Intermediate incubation temperature (18 C), resulted in larvae that displayed a rate of abnormalities close to that observed at 15 C (64%). A similar typology of deformities was observed in fish from all rearing temperatures, with caudal vertebra being the most affected structures and with a low incidence of cranial and appendicular deformities. The effect of temperature in developmental plasticity will lead to osteological abnormalities mainly affecting the caudal vertebrae at 18 C (30%) and particularly the preural vertebra at 15 C (55%). Our results, clearly demonstrate a significant effect of water temperature during egg incubation on the skeletal development of Senegalese sole, indicating that 18 C is the most appropriated temperature. These findings highlight the importance of tightly controlling temperature regimes during the early development of S. senegalensis, and the need for optimizing rearing protocols in order to avoid skeletal disorders or impaired growth.
- Skeletal development and performance of zebrafish Danio rerio (Hamilton, 1822) larvae and juvenile fish fed with different dietsPublication . Cardeira Da Silva, João; Dionísio, Gisela; Bensimon-Brito, A.; Cancela, Leonor; Gavaia, Paulo J.The appearance of skeletal deformities is a major problem associated to intensive, large-scale culture of fish species, affecting growth, development and ultimately, survival of produced fish. Although the mechanisms working behind it are still unclear, it is known that environmental, genetic and nutritional factors play fundamental roles. Given its importance as a vertebrate model to study skeleton-related diseases, the selection of an appropriate dietary protocol is a critical step in order to diminish the nutritional effect on bone and cartilage development.
- Effect of dietary vitamin K supplementation on skeletal development of Danio rerioPublication . Dionísio, Gisela; Cancela, Leonor; Gavaia, Paulo J.Nutritional imbalances affecting bone development have been implicated in the incidence of skeletal deformities, which are acknowledged to constitute one of the major constrains in the production of high quality fish. Several studies have focused on the identification of causes of deformities and associated them to factors such as rearing environment, nutrition and genetics. Among these, larval nutrition at first feeding is one of the key parameters affecting skeletogenesis during early development. Vitamin K (VK) is a liposoluble vitamin classically involved in blood coagulation, and until recently largely disregarded in aquaculture nutrition.
- Temperature affects skeletogenesis during Senegalese sole (Solea senegalensis, Kaup) larval developmentPublication . Gavaia, Paulo J.; Dionísio, Gisela; Campos, C.; Carvalho, A. P.; Conceição, L. E. C.; Cancela, LeonorThe Senegalese sole (Solea senegalensis) is a highly valued species, with particular interest for the southern European aquaculture industry. For the last two decades this species has been transposed for industrial production, but it still presents some constraints as the high frequency of vertebral deformities observed under intensive rearing. The patterns of osteological deformities have previously been described and found to affect mostly the haemal and caudal vertebrae, but no studies have been conducted in order to identify causes for such deformities.
- Comportamento alimentar e resistência à inanição de larvas de camarões ornamentais do género Lysmata (Decapoda: Hippolytidae)Publication . Dionísio, G.; Dinis, Maria Teresa; Calado, RicardoThe present study describes the effect of starvation on the survival of early zoeal stages of Lysmata amboinensis, L. debelius, L. boggessi, L. seticaudata. Studied species occupy different habitats and exhibit different levels of tolerance to the absence of food. Only newly hatched larvae of L. seticaudata and L. boggessi display facultative primary lecithotrophy, moulting from zoea I to zoea II when starved. All studied species show secondary facultative lecithotrophy on the second zoeal stage, being able to moult to zoea III in the absence of food. Nevertheless, this ability was only recorded in larvae at the second zoeal stage which have not been previously exposed to starvation in zoea I. This is the firts record of secondary facultative lecithotrophy among caridena shrimps. Newly hatched larvae of L. amboinensis, L. debelius, L. ankeri e L. seticaudata show a higher tolerance to starvation periods when kept in the dark, compared to photoperiods with 12 or 24 h of light. This fact may be due to a lower larval energetic consumption as a consequence of a decreased swimming activity. Light exposure is not a determinant factor for prey capture in Lysmata larvae, reinforcing the assumption of decapod crustacean larvae not being active predators. Newly hatched larvae of different studied species ingest similar amounts of Artemia nauplii, while L. ankeri and L. seticaudata are able to capture a higher number of enriched Artemia metanuplii. The comparison of morphological and biometrical larval features do not show a particular pattern, being insufficient to explain the differences recorded in the number of ingested preys. The ability displayed by these organisms to capture and ingest large sized preys (e.g. Artemia metanauplii) opens good perspectives for the use of inert diets during early zoeal stages.
- Effect of warfarin in zebrafish (Danio rerio) bone formation during caudal fin regenerationPublication . Dionísio, Gisela; Bensimon-Brito, A.; Gavaia, Paulo J.; Cancela, LeonorIn the last decade, fish has emerged as an important organism for studies on skeletal development in vertebrates, and evidence has been accumulated showing that zebrafish is a suitable system to perform phenotype-based drug screens. The ability to regenerate epidermal injuries is a general feature of most organisms yet only a few can fully regenerate severed appendages comprising several different tissues. Zebrafish is one of the most used models for regeneration studies, creating a powerful tool to study de novo bone formation without affecting vital development processes.
- Skeletal quality in Senegalese sole: characterization of fish resulting from environmental and nutritional trialsPublication . Gavaia, Paulo J.; Dionísio, Gisela; Cardeira Da Silva, João; Cunha, M. E.; Pousão-Ferreira, P.; Conceição, L. E. C.; Cancela, LeonorThe Senegalese sole (Solea senegalensis) is characteristic from southern Europe and Mediterranean. It has recently been adapted for aquaculture production since it is well accepted by consumers and reaches high commercial values. After the initial description of the ontogenic events of skeletogenesis, systematic evaluation of the incidence of skeletal malformations by several groups revealed high levels of skeletal deformities reaching up to 90% of the population.