scholarly journals Morphohistology of the Digestive Tract of the Damsel FishStegastes fuscus(Osteichthyes: Pomacentridae)

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Bhaskara Canan ◽  
Wallace Silva do Nascimento ◽  
Naisandra Bezerra da Silva ◽  
Sathyabama Chellappa
Keyword(s):  
Digestive Tract ◽  
Transition Region ◽  
Digestive System ◽  
Feeding Habits ◽  
Northeastern Brazil ◽  
Muscular Layer ◽  
Pyloric Caeca ◽  
Anterior Intestine ◽  
The Mean ◽  
Tidal Pools

This study investigated the morphohistology of the digestive tract and the mean intestinal coefficient of the damsel fishStegastes fuscuscaptured from the tidal pools of Northeastern Brazil. The wall of the digestive tract ofS. fuscusis composed of the tunica mucosa, tunica muscularis, and tunica serosa. The esophagus is short with sphincter and thick distensible wall with longitudinally folded mucosa. Mucous glands are predominant, and the muscular layer of the esophagus presented striated fibers all along its extension. The transition region close to the stomach shows plain and striated muscular fibers. Between the stomach and intestine, there are three pyloric caeca. The intestine is long and thin with four folds around the stomach. The anterior intestine presents folds similar to those of pyloric caeca. The estimated mean intestinal coefficient and characteristics of the digestive system ofS. fuscuspresent morphological adequacy for both herbivorous and omnivorous feeding habits.

scholarly journals Characterization of amylase and protease activity in the digestive tract of two teleosts (Labeo rohita and Anabas testudineus) with different feeding habits

2021 ◽  
Vol 64 (2) ◽  
pp. 173-179
Author(s):  
Sanjeet Debnath ◽  
Surjya Kumar Saikia
Keyword(s):  
Digestive Tract ◽  
Protease Activity ◽  
Specific Activity ◽  
Labeo Rohita ◽  
Feeding Habits ◽  
Anabas Testudineus ◽  
Pyloric Caeca ◽  
Optimum Ph ◽  
Optimum Ph And Temperature

Two teleosts (Rohu, Labeo rohita and Koi, Anabas testudineus), both with contrasting feeding habits (herbivorous versus carnivorous) were studied for amylase and protease activity concerning different regions of their digestive tracts. Significant differences in enzymatic activity across different regions of the digestive tracts were observed. Rohu, with three equal regions of the stomachless gut, showed the highest amylolytic activity at the posterior digestive tract but the highest proteolytic activity is limited to mid region. Contrary to such observation, Koi with three distinct regions of the digestive tract (stomach, pyloric caeca and intestine), the pyloric caeca exhibited the highest specific activity for both amylase and total protease. The optimum pH and temperature conditions were determined concerning the activity for both amylase and protease.

THE DIGESTIVE TRACT AND ITS RELATION TO FEEDING HABITS IN THE STENOGLOSSAN PROSOBRANCH CORALLIOPHILA ABBREVIATA (LAMARK)

1965 ◽  
Vol 43 (3) ◽  
pp. 447-464 ◽  
Author(s):  
Jonet Ward
Keyword(s):  
Digestive Tract ◽  
Digestive System ◽  
Feeding Habits ◽  
Histological Study ◽  
Dorsal Side ◽  
Animal Tissue ◽  
Salivary Duct ◽  
Faecal Material ◽  
Montastrea Annularis ◽  
Coralliophila Abbreviata

Coralliophila abbreviata is found on partly eroded colonies of Montastrea annularis in the coastal reefs of Barbados and contributes to the destruction of this coral. The habitat and feeding habits have been examined and a histological study has been made of the digestive system. Stomach and faecal material indicate that both the animal tissue and zooxanthellae are ingested. Enzyme tests demonstrate the presence of protein and carbohydrate digesting enzymes. Since this animal has no radula or jaws, it is thought that the muscular proboscis is used as a pump during the ingestion of food. The single salivary duct, formed from the ducts of the paired salivary glands, opens into the oral tube on the dorsal side of the mouth. It is suggested that its secretion may aid in penetration of the coral epidermis before ingestion begins.

scholarly journals The internal CO 2 threat to fish: high P CO 2 in the digestive tract

2019 ◽  
Vol 286 (1907) ◽  
pp. 20190832 ◽  
Author(s):  
Chris M. Wood ◽  
Junho Eom
Keyword(s):  
Climate Change ◽  
Rainbow Trout ◽  
Freshwater Fish ◽  
Digestive Tract ◽  
Venous Blood ◽  
External Environment ◽  
Current Concern ◽  
Anterior Intestine ◽  
The Mean

Our goal was to use novel fibreoptic sensors to make the first direct P CO 2 measurements in the digestive tracts of live freshwater fish (anaesthetized, artificially ventilated, 12°C). P CO 2 levels in gastrointestinal fluids were substantially higher than in blood, and were elevated after feeding. In the carnivorous, gastric rainbow trout, the mean P CO 2 in various parts of the tract increased from 7–13 torr (1 torr = 0.1333 kPa) during fasting to 20–41 torr after feeding, relative to arterial levels of 3.5–4 torr. In the agastric, omnivorous goldfish, the mean gut levels varied from 10–13 torr in fasted animals to 14–18 torr in fed animals, relative to arterial levels of 5–7 torr. These elevated P CO 2 values were associated with surprisingly high HC O 3 − concentrations (greater than 40 mmol l −1 ) in the intestinal chyme. Incubations of food pellets with acid or water revealed endogenous P CO 2 generation sufficient to explain gastric P CO 2 in fed trout and anterior intestine P CO 2 in fed goldfish. The impacts of possible equilibration with venous blood draining the tract are assessed. We conclude that fish are already coping with P CO 2 levels in the internal gastrointestinal environment many-fold greater than those of current concern in the external environment for climate change and aquacultural scenarios.

scholarly journals Pentastomids infecting an invader lizard, Hemidactylus mabouia (Gekkonidae) in northeastern Brazil

2008 ◽  
Vol 68 (3) ◽  
pp. 611-615 ◽  
Author(s):  
LA. Anjos ◽  
WO. Almeida ◽  
A. Vasconcellos ◽  
EMX. Freire ◽  
CFD. Rocha
Keyword(s):  
Feeding Habits ◽  
Infection Intensity ◽  
First Record ◽  
Host Population ◽  
Northeastern Brazil ◽  
Parasitism Rate ◽  
Intensity Of Infection ◽  
New Host ◽  
Single Host ◽  
Hemidactylus Mabouia

From January to April 2006, 37 specimens of Hemidactylus mabouia were collected in houses, in the municipality of Barbalha (7° 20' S and 39° 18' W), Ceará State, Northeast Brazil. Among the individuals captured, 17 were infected with pentastomids, totalling a prevalence of 45.9%, which did not differ between sexes. Host size did not influence the infection intensity. Two species of pentastomids were found: Raillietiella frenatus and R. mottae. The prevalence of R. frenatus (43.2%) was higher than R. mottae (2.7%), whereas the infection intensity of R. frenatus was comparatively lower (1.8 ± 1.4) than R. mottae (36 parasites in a single host). Overall mean intensity of infection was 3.8 ± 8.4 pentastomids. We found no pentastomid infecting juvenile geckos. The parameters of infection in this host population are in accordance to the findings of other studies, in which the high parasitism rate was associated to the feeding habits of geckos living in houses and buildings. Hemidactylus mabouia is a new host to R. mottae and the infection by R. frenatus is the first record of the occurrence this pentastomid species in Brazil.

scholarly journals The Dasypodidae (Mammalia, Xenarthra) from the Urso Fóssil Cave (Quaternary), Parque Nacional de Ubajara, State of Ceará, Brazil: paleoecological and taxonomic aspects

2014 ◽  
Vol 86 (1) ◽  
pp. 147-158 ◽  
Author(s):  
PAULO V. OLIVEIRA ◽  
ANA MARIA RIBEIRO ◽  
ÉDISON V. OLIVEIRA ◽  
MARIA SOMÁLIA S. VIANA
Keyword(s):  
Environmental Conditions ◽  
Feeding Habits ◽  
Early Holocene ◽  
Northeastern Brazil ◽  
Dasypus Novemcinctus ◽  
Sediment Samples ◽  
Wide Geographical Distribution ◽  
Anthropogenic Action ◽  
Euphractus Sexcinctus ◽  
Northwest Region

This paper deals with xenarthrans osteoderms assigned to Dasypus aff. D. novemcinctus, Euphractus sexcinctus and Cabassous sp. The material was collected in subsurface, from 0.10 to 0.60 m in the Urso Fóssil Cave, Parque Nacional de Ubajara, State of Ceará, northeastern Brazil. The ages of sediment samples from levels 4 and 5 (depths of 0.40 and 0.50 m) were determined by thermoluminescence technique, and indicated ages of 8,000 and 8,200 years BP for each layer respectively. The presence in these layers of early Holocene xenarthrans taxa can contribute to the understanding of the biotic evolution of the northwest region of Ceará during the last 10,000 years. Two of the three identified taxa still occur in the region: Dasypus novemcinctus and Euphractus sexcinctus. The Dasypodidae fauna here reported includes animals with generalist feeding habits and current wide geographical distribution. It is suggested, therefore, that the climatic and environmental conditions in the early Holocene were very similar the actual ones, and that the absence of Cabassous may be conditioned to other factors, such as anthropogenic action and loss of habitat by fragmentation of the vegetation.

Feeding ecology of Symbolophorus californiensis larvae (Teleostei: Myctophidae) in the southern transition region of the western North Pacific

2009 ◽  
Vol 90 (6) ◽  
pp. 1249-1256 ◽  
Author(s):  
Chiyuki Sassa
Keyword(s):  
Transition Region ◽  
North Pacific ◽  
Western North Pacific ◽  
Developmental Stages ◽  
Feeding Habits ◽  
Larval Growth ◽  
Trophic Niche ◽  
Size Class ◽  
Gut Contents ◽  
Wide Range

The feeding habits of myctophid larvae of Symbolophorus californiensis were examined in the southern transition region of the western North Pacific where the main spawning and nursery grounds of S. californiensis are formed. This species is a key component of the pelagic ecosystems of this region, and their larvae attain one of the largest sizes among myctophids. To analyse gut contents larvae, including most life history stages after yolk-sac absorption (3.7 to 22.2 mm body length (BL)), were collected in the upper 100 m layer in 1997 and 1998. Feeding incidence was higher during the day than at night (53.1–92.3% versus 0–5.6%), and daytime feeding incidence increased gradually with larval growth. Larvae fed mainly on copepods of various developmental stages. Larvae of S. californiensis showed an ontogenetic change in their diet: larvae ≤7.9 mm BL (i.e. preflexion stage) fed mainly on copepod eggs and nauplii, while the larvae ≥8 mm BL consumed mainly calanoid copepodites such as Pseudocalanus and Paracalanus spp. In the largest size-class (16–22.2 mm BL), the furcilia stage of euphausiids was also an important prey item. There was an increase in the average prey size with growth in larvae ≤11.9 mm BL, while the number of prey eaten positively correlated with growth in larvae ≥12 mm BL. The trophic niche breadth also increased with larval growth, which would ensure a wide range of available food resources for the larger size-class larvae.

The enteric nervous system of echinoderms: unexpected complexity revealed by neurochemical analysis

2001 ◽  
Vol 204 (5) ◽  
pp. 865-873
Author(s):  
J.E. Garcia-Arraras ◽  
M. Rojas-Soto ◽  
L.B. Jimenez ◽  
L. Diaz-Miranda
Keyword(s):  
Nervous System ◽  
Enteric Nervous System ◽  
Digestive Tract ◽  
Radial Nerve ◽  
Digestive System ◽  
Nerve Ring ◽  
Point Of View ◽  
Distinct Component ◽  
Future Studies ◽  
Neurochemical Analysis

Echinoderms are one of the most important groups of metazoans from the point of view of evolution, ecology and abundance. Nevertheless, their nervous system has been little studied. Particularly unexplored have been the components of the nervous system that lie outside the ectoneural and hyponeural divisions of the main nerve ring and radial nerve cords. We have gathered information on the nervous components of the digestive tract of echinoderms and demonstrate an unexpected level of complexity in terms of neurons, nerve plexi, their location and neurochemistry. The nervous elements within the digestive system consist of a distinct component of the echinoderm nervous system, termed the enteric nervous system. However, the association between the enteric nervous system and the ectoneural and hyponeural components of the nervous system is not well established. Our findings also emphasize the importance of the large lacunae in the neurobiology of echinoderms, a feature that should be addressed in future studies.

scholarly journals Impact of a dedicated multidisciplinary meeting on the management of superficial cancers of the digestive tract

2018 ◽  
Vol 06 (12) ◽  
pp. E1470-E1476 ◽  
Author(s):  
Solène Dermine ◽  
Maximilien Barret ◽  
Caroline Prieux ◽  
Sophie Ribière ◽  
Sarah Leblanc ◽  
...  
Keyword(s):  
Digestive Tract ◽  
Endoscopic Resection ◽  
Gastrointestinal Endoscopy ◽  
Lesion Size ◽  
Concordance Rate ◽  
Resection Rate ◽  
Tertiary Referral Center ◽  
Multidisciplinary Meeting ◽  
The Mean ◽  
The Impact

Abstract Background The recent development of endoscopic resection for superficial gastrointestinal cancers could justify the need for a dedicated oncological multidisciplinary meeting (MDM). The aim of our study was to evaluate the impact of the dedicated MDM on the management of superficial cancers of the digestive tract. Methods A dedicated MDM was developed at our tertiary referral center. A retrospective review of the MDM conclusions for all patients referred from March 2015 to March 2017 was performed. Outcomes measurements were the outcomes of endoscopic resection, and the concordance rate between the MDM recommendations, European Society of Gastrointestinal Endoscopy (ESGE) guidelines, and final patient management. Results In total, 153 patients with a median age of 69 years were included. Half of the patients had major comorbidities. The mean lesion size was 25 mm, and R0 and curative resection rate were 73.9 % and 56.9 %, respectively. Forty-three patients had an indication for surgery after endoscopic resection. The concordance rate between ESGE guidelines and MDM recommendation was 92.2 %, and 12 patients did not receive the treatment recommended due to comorbidities. Conclusion A MDM dedicated to superficial tumors helped tailor the ESGE guidelines to each patient in order to avoid unnecessary surgery.

scholarly journals Occurrence of Tetracampos ciliotheca and Proteocephalus glanduligerus in Clarias gariepinus (Burchell, 1822) collected from the Vaal Dam, South Africa

2013 ◽  
Vol 80 (1) ◽  
Author(s):  
Grace Madanire-Moyo ◽  
Annemariè Avenant-Oldewage
Keyword(s):  
South Africa ◽  
Digestive Tract ◽  
Standard Length ◽  
Feeding Habits ◽  
Clarias Gariepinus ◽  
Male And Female ◽  
Mean Intensity ◽  
Gill Nets ◽  
Larval Stages ◽  
Vaal Dam

Cestodes are parasitic flatworms that live in the digestive tract of vertebrates as adults and often in the liver, muscle, haemocoel, mesentery and brain of various animals as larval stages. To identify the cestodes infecting Clarias gariepinus Burchell, 1822 (sharptooth catfish) in the Vaal Dam, a total of 45 host specimens were collected with the aid of gill nets between October 2011, January and April 2012. The fish were sacrificed and examined for cestode parasites. Two adult cestodes, Tetracampos ciliotheca Wedl, 1861 (prevalence 86.7%, mean intensity = 15, n = 45) and Proteocephalus glanduligerus (Janicki, 1928) (prevalence 51.1%, mean intensity = 5, n = 45) were found in the intestines of the catfish. Both T. ciliotheca and P. glanduligerus are new locality records. There were statistically insignificant differences in the infection of the male and female C. gariepinu. Fish with standard length ranging from 40 cm – 54 cm (≥ 3 years) had the highest prevalence and mean intensity while those ranging from 10 cm – 24 cm (< 1 year) had the lowest prevalence and mean intensity for both cestodes. The study highlights the importance of changing feeding habits of C. gariepinus with age on the prevalence and mean intensity of the two gastrointestinal cestode parasites.

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