The Experts below are selected from a list of 7062 Experts worldwide ranked by ideXlab platform

Montse Perez - One of the best experts on this subject based on the ideXlab platform.

  • prey capture ingestion and digestion dynamics of octopus vulgaris paralarvae fed live zooplankton
    Frontiers in Physiology, 2017
    Co-Authors: M Nande, Pablo Presa, Alvaro Roura, Paul L R Andrews, Montse Perez
    Abstract:

    Octopus vulgaris is a species of great interest in research areas such as neurobiology, ethology and ecology but is also a candidate species for aquaculture as food resource as well as source to alleviating the fishing pressure on its wild populations. This study aimed to characterize the predatory behaviour of O. vulgaris paralarvae and to quantify their digestive activity. Those processes were affordable using the video-recording analysis of 3 dph, mantle-transparent paralarvae feeding on 18 types of live zooplanktonic prey. We show that octopus paralavae attack, immobilize, drill and ingest live cladocerans and copepods with 100% efficiency, which decreases dramatically to 60% on decapod prey (Pisidia longicornis). The majority (85%) of successful attacks targeted the prey cephalothorax while unsuccessful attacks either targeted the dorsal cephalothorax or involved prey defensive strategies (e.g. juvenile crab megalopa) or prey protected by thick carapaces (e.g. Gammaridae). After immobilization, the beak, the buccal mass and the radula were involved in exoskeleton penetration and content ingestion. Ingestion time of prey content was rapid for copepods and cladocerans (73.13 ± 23.34 s) but much slower for decapod zoeae and euphasiids (152.49 ± 29.40 s). Total contact time with prey was always <5min. Contrary to the conventional view of crop filling dynamics observed in adult Octopus vulgaris, food accumulated first in the Stomach of paralarvae and the crop filled after the Stomach Volume plateaued. Peristaltic crop contractions (~18/min) moved food into the Stomach (contractions ~30/min) from where it passed to the caecum. Pigmented food tracers were seen to enter the digestive gland, 312 ± 32 s after the crop reached its maximum Volume. Digestive tract contents passed into the terminal intestine by peristalsis (contraction frequency ~50/min) and defaecation was accompanied by an increased frequency of mantle contractions. Current results provide novel insights into both, O. vulgaris paralarvae – live prey capture strategies and the physiological mechanisms following ingestion, a key information to develop an effective rearing protocol for O. vulgaris.

  • Prey Capture, Ingestion, and Digestion Dynamics of Octopus vulgaris Paralarvae Fed Live Zooplankton
    Frontiers Media S.A., 2017
    Co-Authors: M Nande, Pablo Presa, Alvaro Roura, Paul L R Andrews, Montse Perez
    Abstract:

    Octopus vulgaris is a species of great interest in research areas such as neurobiology, ethology, and ecology but also a candidate species for aquaculture as a food resource and for alleviating the fishing pressure on its wild populations. This study aimed to characterize the predatory behavior of O. vulgaris paralarvae and to quantify their digestive activity. Those processes were affordable using the video-recording analysis of 3 days post-hatching (dph), mantle-transparent paralarvae feeding on 18 types of live zooplanktonic prey. We show for the first time in a live cephalopod that octopus paralarvae attack, immobilize, drill, and ingest live cladocerans and copepods with 100% efficiency, which decreases dramatically to 60% on decapod prey (Pisidia longicornis). The majority (85%) of successful attacks targeted the prey cephalothorax while unsuccessful attacks either targeted the dorsal cephalothorax or involved prey defensive strategies (e.g., juvenile crab megalopae) or prey protected by thick carapaces (e.g., gammaridae amphipods). After immobilization, the beak, the buccal mass and the radula were involved in exoskeleton penetration and content ingestion. Ingestion time of prey content was rapid for copepods and cladocerans (73.13 ± 23.34 s) but much slower for decapod zoeae and euphausiids (152.49 ± 29.40 s). Total contact time with prey was always <5 min. Contrary to the conventional view of crop filling dynamics observed in adult O. vulgaris, food accumulated first in the Stomach of paralarvae and the crop filled after the Stomach Volume plateaued. Peristaltic crop contractions (~18/min) moved food into the Stomach (contractions ~30/min) from where it passed to the caecum. Pigmented food particles were seen to enter the digestive gland, 312 ± 32 s after the crop reached its maximum Volume. Digestive tract contents passed into the terminal intestine by peristalsis (contraction frequency ~50/min) and defaecation was accompanied by an increased frequency of mantle contractions. Current results provide novel insights into both, O. vulgaris paralarvae—live prey capture strategies and the physiological mechanisms following ingestion, providing key information required to develop an effective rearing protocol for O. vulgaris paralarvae

M Nande - One of the best experts on this subject based on the ideXlab platform.

  • prey capture ingestion and digestion dynamics of octopus vulgaris paralarvae fed live zooplankton
    Frontiers in Physiology, 2017
    Co-Authors: M Nande, Pablo Presa, Alvaro Roura, Paul L R Andrews, Montse Perez
    Abstract:

    Octopus vulgaris is a species of great interest in research areas such as neurobiology, ethology and ecology but is also a candidate species for aquaculture as food resource as well as source to alleviating the fishing pressure on its wild populations. This study aimed to characterize the predatory behaviour of O. vulgaris paralarvae and to quantify their digestive activity. Those processes were affordable using the video-recording analysis of 3 dph, mantle-transparent paralarvae feeding on 18 types of live zooplanktonic prey. We show that octopus paralavae attack, immobilize, drill and ingest live cladocerans and copepods with 100% efficiency, which decreases dramatically to 60% on decapod prey (Pisidia longicornis). The majority (85%) of successful attacks targeted the prey cephalothorax while unsuccessful attacks either targeted the dorsal cephalothorax or involved prey defensive strategies (e.g. juvenile crab megalopa) or prey protected by thick carapaces (e.g. Gammaridae). After immobilization, the beak, the buccal mass and the radula were involved in exoskeleton penetration and content ingestion. Ingestion time of prey content was rapid for copepods and cladocerans (73.13 ± 23.34 s) but much slower for decapod zoeae and euphasiids (152.49 ± 29.40 s). Total contact time with prey was always <5min. Contrary to the conventional view of crop filling dynamics observed in adult Octopus vulgaris, food accumulated first in the Stomach of paralarvae and the crop filled after the Stomach Volume plateaued. Peristaltic crop contractions (~18/min) moved food into the Stomach (contractions ~30/min) from where it passed to the caecum. Pigmented food tracers were seen to enter the digestive gland, 312 ± 32 s after the crop reached its maximum Volume. Digestive tract contents passed into the terminal intestine by peristalsis (contraction frequency ~50/min) and defaecation was accompanied by an increased frequency of mantle contractions. Current results provide novel insights into both, O. vulgaris paralarvae – live prey capture strategies and the physiological mechanisms following ingestion, a key information to develop an effective rearing protocol for O. vulgaris.

  • Prey Capture, Ingestion, and Digestion Dynamics of Octopus vulgaris Paralarvae Fed Live Zooplankton
    Frontiers Media S.A., 2017
    Co-Authors: M Nande, Pablo Presa, Alvaro Roura, Paul L R Andrews, Montse Perez
    Abstract:

    Octopus vulgaris is a species of great interest in research areas such as neurobiology, ethology, and ecology but also a candidate species for aquaculture as a food resource and for alleviating the fishing pressure on its wild populations. This study aimed to characterize the predatory behavior of O. vulgaris paralarvae and to quantify their digestive activity. Those processes were affordable using the video-recording analysis of 3 days post-hatching (dph), mantle-transparent paralarvae feeding on 18 types of live zooplanktonic prey. We show for the first time in a live cephalopod that octopus paralarvae attack, immobilize, drill, and ingest live cladocerans and copepods with 100% efficiency, which decreases dramatically to 60% on decapod prey (Pisidia longicornis). The majority (85%) of successful attacks targeted the prey cephalothorax while unsuccessful attacks either targeted the dorsal cephalothorax or involved prey defensive strategies (e.g., juvenile crab megalopae) or prey protected by thick carapaces (e.g., gammaridae amphipods). After immobilization, the beak, the buccal mass and the radula were involved in exoskeleton penetration and content ingestion. Ingestion time of prey content was rapid for copepods and cladocerans (73.13 ± 23.34 s) but much slower for decapod zoeae and euphausiids (152.49 ± 29.40 s). Total contact time with prey was always <5 min. Contrary to the conventional view of crop filling dynamics observed in adult O. vulgaris, food accumulated first in the Stomach of paralarvae and the crop filled after the Stomach Volume plateaued. Peristaltic crop contractions (~18/min) moved food into the Stomach (contractions ~30/min) from where it passed to the caecum. Pigmented food particles were seen to enter the digestive gland, 312 ± 32 s after the crop reached its maximum Volume. Digestive tract contents passed into the terminal intestine by peristalsis (contraction frequency ~50/min) and defaecation was accompanied by an increased frequency of mantle contractions. Current results provide novel insights into both, O. vulgaris paralarvae—live prey capture strategies and the physiological mechanisms following ingestion, providing key information required to develop an effective rearing protocol for O. vulgaris paralarvae

Susanne Holmgren - One of the best experts on this subject based on the ideXlab platform.

  • mechanisms controlling Stomach Volume of the atlantic cod gadus morhua following gastric distension
    The Journal of Experimental Biology, 1992
    Co-Authors: David J Grove, Susanne Holmgren
    Abstract:

    1. 1. Inflation of the cardiac Stomach of the cod induced rhythmic contractions of the muscles and a slow increase in Stomach Volume towards a maximum. After deflation, the Stomach remained relaxed and easily distensible for one or more hours. Section of the vagal tracts to the Stomach did not change the response. 2. 2. Inflation in vitro produced a somewhat faster relaxation and a much faster recovery to the pre-distended state than occurred in vivo . Stimulation of the cut ends of the vagus raised gastric tone and increased resistance to distension, an effect mediated by cholinergic nerves. 3. 3. Tetrodotoxin and atropine relaxed the Stomach so that distension was rapid and the maximal Volume increased, revealing slower, possibly myogenic, contractions. 4. 4. The 5-hydroxytryptamine (5-HT) antagonist methysergide, vasoactive intestinal polypeptide (VIP), met-enkephalin and neurotensin did not affect the responses to distension. Somatostatin abolished spontaneous contractions in the resting Stomach and lowered gastric tone, but did not further affect the responses to distension. 5. 5. In conclusion, cholinergic nerves maintain gastric tone in the cod. 5-HT neurones are absent in the cod Stomach, and there are no indications of a 5-HT/VIP-controlled mechanism operating during distension. The effect of somatostatin differs from that in rainbow trout. 6. 6. For comparison with trout and cod, responses to in vivo gastric distension are also described for the flatfish Scophthalmus maximus, Scophthalmus rhombus, Limanda limanda and Pleuronectes platessa

  • intrinsic mechanisms controlling cardiac Stomach Volume of the rainbow trout oncorhynchus mykiss following gastric distension
    The Journal of Experimental Biology, 1992
    Co-Authors: David J Grove, Susanne Holmgren
    Abstract:

    1. 1. Inflation of the cardiac Stomach of the rainbow trout induced reflex muscular contractions. The Stomach then slowly relaxed asymptotically towards its maximum Volume. Continued distension caused the Stomach to become compliant and this was irreversible within the time course of each experiment (8h). Repeated periods of rest and distension revealed a short-term inhibition of reflex contractions which recovered as resting periods were extended. Sectioning the vagosympathetic trunk did not influence the response to distension. Similar responses occurred in isolated, perfused Stomachs. 2. 2. Both tetrodotoxin and atropine plus methysergide induced immediate compliance, suggesting that it was caused by the blockade of enteric excitatory neurones. Atropine alone primarily reduced reflex contractions whilst methysergide completed this suppression and induced profound gastric relaxation. 3. 3. Somatostatin reversibly suppressed reflex contractions whilst vasoactive intestinal polypeptide (VIP) induced gastric relaxation. 4. 4. A model is proposed in which distension initially causes reflex activity via cholinergic and serotonergic nerves, whilst gastric tone remains high. Somatostatin then suppresses rhythmic contractions, whilst VIP suppresses the tryptaminergic mechanisms that maintain gastric tone. 5. 5. The rainbow trout Stomach possesses intrinsic mechanisms that mimic the extrinsic, nerve-controlled ‘receptive relaxation’ or ‘accommodation’ that follows feeding in higher vertebrates.

Scrocchi Manfrini, Gustavo Jose - One of the best experts on this subject based on the ideXlab platform.

  • Trophic ecology of Liolaemus espinozai Abdala, 2005 (Sauria: Liolaemidae) in Campo El Arenal, Catamarca, Argentina.
    'Asociacion Civil Herpetologica Argentina', 2020
    Co-Authors: Cabrera, María Paula, Scrocchi Manfrini, Gustavo Jose
    Abstract:

    Trophic ecology of Liolaemus espinozai Abdala, 2005 (Sauria: Liolaemidae) in Campo El Arenal, Catamarca, Argentina. Diet studies are essential to understand the ecological and evolutionary phenomena that influence animals, because they provide information on the species interactions with the environment and with other organisms. We described the trophic ecology of Liolaemus espinozai from Campo El Arenal (Catamarca, Argentina), type locality of the species, using the Stomach contents of males and females. We determined the importanceof each prey item, trophic amplitude and diversity, and similarity of Stomach contents between males and females; the Stomach Volume was compared intra and intersexually and we evaluated the relationship between the size of the individual and preys. We determined a total of 3151 preys grouped into 17 trophic categories. The population is generalist and insectivorous, feeding mainly on ants (formicids); the trophic amplitude is low, with large fluctuations throughout theyear. There is no relationship between body and head size of lizards and prey size. Males and females share about 80% of the diet, so there would be competition for food. The differences observed in the different periods would be due to a different activity pattern between sexsDiet studies are essential to understand the ecological and evolutionary phenomena that influence animals, because they provide information on the species interactions with the environment and with other organisms. We described the trophic ecology of Liolaemus espinozai from Campo El Arenal (Catamarca, Argentina), type locality of the species, using the Stomach contents of males and females. We determined the importance of each prey item, trophic amplitude and diversity, and similarity of Stomach contents between males and females; the Stomach Volume was compared intra and intersexually and we evaluated the relationship between the size of the individual and preys. We determined a total of 3151 preys grouped into 17 trophic categories. The population is generalist and insectivorous, feeding mainly on ants (formicids); the trophic amplitude is low, with large fluctuations throughout the year. There is no relationship between body and head size of lizards and prey size. Males and females share about 80% of the diet, so there would be competition for food. The differences observed in the different periods would be due to a different activity pattern between sexsFil: Cabrera, María Paula. Fundación Miguel Lillo. Dirección de Zoología; ArgentinaFil: Scrocchi Manfrini, Gustavo Jose. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico - Tucumán. Unidad Ejecutora Lillo; Argentin

  • Trophic ecology of Liolaemus espinozai Abdala, 2005 (Sauria: Liolaemidae) in Campo El Arenal, Catamarca, Argentina
    2020
    Co-Authors: Cabrera, María Paula, Scrocchi Manfrini, Gustavo Jose
    Abstract:

    Diet studies are essential to understand the ecological and evolutionary phenomena that influence animals, because they provide information on the species interactions with the environment and with other organisms. We described the trophic ecology of Liolaemus espinozai from Campo El Arenal (Catamarca, Argentina), type locality of the species, using the Stomach contents of males and females. We determined the importance of each prey item, trophic amplitude and diversity, and similarity of Stomach contents between males and females; the Stomach Volume was compared intra and intersexually and we evaluated the relationship between the size of the individual and preys. We determined a total of 3151 preys grouped into 17 trophic categories. The population is generalist and insectivorous, feeding mainly on ants (formicids); the trophic amplitude is low, with large fluctuations throughout the year. There is no relationship between body and head size of lizards and prey size. Males and females share about 80% of the diet, so there would be competition for food. The differences observed in the different periods would be due to a different activity pattern between sexs.El estudio de la dieta es fundamental para entender los fenómenos ecológicos y evolutivos que actúan en los animales, ya que brinda información sobre las relaciones de las especies con el ambiente y con otros organismos. Se describe la ecología trófica de una población de Liolaemus espinozai de Campo El Arenal (Catamarca, Argentina) localidad tipo de la especie. Con base en el análisis del contenido estomacal de machos y hembras, se determinó la importancia de cada ítem presa, la amplitud y diversidad trófica y la semejanza del contenido estomacal entre los sexos, en diferentes épocas del año; además, se comparó el Volumen del contenido estomacal intrasexual e intersexual y se evaluó la relación entre el tamaño del individuo con el de la presa. Se determinó un total de 3151 presas agrupadas en 17 categorías tróficas. La población estudiada es generalista e insectívora, alimentándose principalmente de hormigas (formícidos); presenta una amplitud trófica baja, con grandes fluctuaciones a lo largo del año. No existe relación entre el tamaño del cuerpo y de la cabeza de los individuos con el Volumen de las presas consumidas. Machos y hembras comparten alrededor del 80% de la dieta, por lo que existiría competencia por el alimento. Las diferencias observadas en las distintas épocas se deberían a un patrón de actividad distinto entre ellos.Asociación Herpetológica Argentin

Alvaro Roura - One of the best experts on this subject based on the ideXlab platform.

  • prey capture ingestion and digestion dynamics of octopus vulgaris paralarvae fed live zooplankton
    Frontiers in Physiology, 2017
    Co-Authors: M Nande, Pablo Presa, Alvaro Roura, Paul L R Andrews, Montse Perez
    Abstract:

    Octopus vulgaris is a species of great interest in research areas such as neurobiology, ethology and ecology but is also a candidate species for aquaculture as food resource as well as source to alleviating the fishing pressure on its wild populations. This study aimed to characterize the predatory behaviour of O. vulgaris paralarvae and to quantify their digestive activity. Those processes were affordable using the video-recording analysis of 3 dph, mantle-transparent paralarvae feeding on 18 types of live zooplanktonic prey. We show that octopus paralavae attack, immobilize, drill and ingest live cladocerans and copepods with 100% efficiency, which decreases dramatically to 60% on decapod prey (Pisidia longicornis). The majority (85%) of successful attacks targeted the prey cephalothorax while unsuccessful attacks either targeted the dorsal cephalothorax or involved prey defensive strategies (e.g. juvenile crab megalopa) or prey protected by thick carapaces (e.g. Gammaridae). After immobilization, the beak, the buccal mass and the radula were involved in exoskeleton penetration and content ingestion. Ingestion time of prey content was rapid for copepods and cladocerans (73.13 ± 23.34 s) but much slower for decapod zoeae and euphasiids (152.49 ± 29.40 s). Total contact time with prey was always <5min. Contrary to the conventional view of crop filling dynamics observed in adult Octopus vulgaris, food accumulated first in the Stomach of paralarvae and the crop filled after the Stomach Volume plateaued. Peristaltic crop contractions (~18/min) moved food into the Stomach (contractions ~30/min) from where it passed to the caecum. Pigmented food tracers were seen to enter the digestive gland, 312 ± 32 s after the crop reached its maximum Volume. Digestive tract contents passed into the terminal intestine by peristalsis (contraction frequency ~50/min) and defaecation was accompanied by an increased frequency of mantle contractions. Current results provide novel insights into both, O. vulgaris paralarvae – live prey capture strategies and the physiological mechanisms following ingestion, a key information to develop an effective rearing protocol for O. vulgaris.

  • Prey Capture, Ingestion, and Digestion Dynamics of Octopus vulgaris Paralarvae Fed Live Zooplankton
    Frontiers Media S.A., 2017
    Co-Authors: M Nande, Pablo Presa, Alvaro Roura, Paul L R Andrews, Montse Perez
    Abstract:

    Octopus vulgaris is a species of great interest in research areas such as neurobiology, ethology, and ecology but also a candidate species for aquaculture as a food resource and for alleviating the fishing pressure on its wild populations. This study aimed to characterize the predatory behavior of O. vulgaris paralarvae and to quantify their digestive activity. Those processes were affordable using the video-recording analysis of 3 days post-hatching (dph), mantle-transparent paralarvae feeding on 18 types of live zooplanktonic prey. We show for the first time in a live cephalopod that octopus paralarvae attack, immobilize, drill, and ingest live cladocerans and copepods with 100% efficiency, which decreases dramatically to 60% on decapod prey (Pisidia longicornis). The majority (85%) of successful attacks targeted the prey cephalothorax while unsuccessful attacks either targeted the dorsal cephalothorax or involved prey defensive strategies (e.g., juvenile crab megalopae) or prey protected by thick carapaces (e.g., gammaridae amphipods). After immobilization, the beak, the buccal mass and the radula were involved in exoskeleton penetration and content ingestion. Ingestion time of prey content was rapid for copepods and cladocerans (73.13 ± 23.34 s) but much slower for decapod zoeae and euphausiids (152.49 ± 29.40 s). Total contact time with prey was always <5 min. Contrary to the conventional view of crop filling dynamics observed in adult O. vulgaris, food accumulated first in the Stomach of paralarvae and the crop filled after the Stomach Volume plateaued. Peristaltic crop contractions (~18/min) moved food into the Stomach (contractions ~30/min) from where it passed to the caecum. Pigmented food particles were seen to enter the digestive gland, 312 ± 32 s after the crop reached its maximum Volume. Digestive tract contents passed into the terminal intestine by peristalsis (contraction frequency ~50/min) and defaecation was accompanied by an increased frequency of mantle contractions. Current results provide novel insights into both, O. vulgaris paralarvae—live prey capture strategies and the physiological mechanisms following ingestion, providing key information required to develop an effective rearing protocol for O. vulgaris paralarvae