967 resultados para feeding activity


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The feeding habits and biological aspects of the reproductive cycle of two-spot astyanax, Astyanax cf. lacustris (Reinhardt, 1874) were investigated. Fish samples were captured on a monthly basis, using gillnets of 4 cm mesh size, from the Piató Lake, Assu, Rio Grande do Norte, during the period of September, 2006 to August, 2007. Physico-chemical parameters, such as, temperature, electrical conductivity and dissolved oxygen of the lake were registered. The monthly values of rainfall also were obtained. The 360 individuals captured, were measured, weighed, dissected, and stomach weight and the stage of gonadal maturity were registered. The stomach contents analyses were carried out based on volumetric method, points, frequency of occurrence and applying the Index of Relative Importance. The degrees of repletion of the stomachs were determined besides the Index of Repletion relating to feeding activity variations and frequency of ingestion with limnological parameters and rainfall. The food items identified were separated into distinct groups according to their origin. Sex ratio and Gonadosomatic Relation of females were verified to determine the spawning period and fecundity. The physico-chemical parameters presented the following annual mean values: temperature = 28.8ºC, electrical conductivity = 992.5 µS.cm-1; dissolved oxygen = 4.9 mg.L-1 during the study period. The annual mean of the rainfall was 63.5 mm. The results indicate that this species present an omnivorous feeding habit with a tendency towards insectivory, with an increase in feeding activity during the dry season. The aquatic oxygen to interfere very importance in the feeding activity than the others factors physico-chemicals of water and rainfall. There was a predominance of females, with a sex proportion of 1M:7F. The macroscopic characteristics of the ovaries and testicles revealed four stages of gonadal development: immature, maturing, mature and spent. A temporal variation was observed for the gonadal development of males and females. There was reproductive activity through out the year, with peaks in the months of February, April and June to correspond with the rain of precipitation of the region. The mean fecundity was 7.681 mature oocytes, varying from 4.476 to 12.036, with mean of 7.681. There was positive relation between fecundity and body mass. Condition Factor is not an efficient indicator of the reproductive period of this species. The species A. cf. lacustris is an opportunist and is well adapted to the conditions of the semi-arid Caatinga Biome

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The feeding habits and biological aspects of the reproductive cycle of two-spot astyanax, Astyanax cf. lacustris (Reinhardt, 1874) were investigated. Fish samples were captured on a monthly basis, using gillnets of 4 cm mesh size, from the Piató Lake, Assu, Rio Grande do Norte, during the period of September, 2006 to August, 2007. Physico-chemical parameters, such as, temperature, electrical conductivity and dissolved oxygen of the lake were registered. The monthly values of rainfall also were obtained. The 360 individuals captured, were measured, weighed, dissected, and stomach weight and the stage of gonadal maturity were registered. The stomach contents analyses were carried out based on volumetric method, points, frequency of occurrence and applying the Index of Relative Importance. The degrees of repletion of the stomachs were determined besides the Index of Repletion relating to feeding activity variations and frequency of ingestion with limnological parameters and rainfall. The food items identified were separated into distinct groups according to their origin. Sex ratio and Gonadosomatic Relation of females were verified to determine the spawning period and fecundity. The physico-chemical parameters presented the following annual mean values: temperature = 28.8ºC, electrical conductivity = 992.5 µS.cm-1; dissolved oxygen = 4.9 mg.L-1 during the study period. The annual mean of the rainfall was 63.5 mm. The results indicate that this species present an omnivorous feeding habit with a tendency towards insectivory, with an increase in feeding activity during the dry season. The aquatic oxygen to interfere very importance in the feeding activity than the others factors physico-chemicals of water and rainfall. There was a predominance of females, with a sex proportion of 1M:7F. The macroscopic characteristics of the ovaries and testicles revealed four stages of gonadal development: immature, maturing, mature and spent. A temporal variation was observed for the gonadal development of males and females. There was reproductive activity through out the year, with peaks in the months of February, April and June to correspond with the rain of precipitation of the region. The mean fecundity was 7.681 mature oocytes, varying from 4.476 to 12.036, with mean of 7.681. There was positive relation between fecundity and body mass. Condition Factor is not an efficient indicator of the reproductive period of this species. The species A. cf. lacustris is an opportunist and is well adapted to the conditions of the semi-arid Caatinga Biome

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This study analyze the consequences of unilateral and bilateral ablation based on ovigerous percentage, consecutive spawns, and secondary effects of the surgical process in the females of Macrobrachium rosenbergii (De Man, 1879). Two experiments were carried out with four and seven months old females in intermolt stage. Each experiment was comprised of control, unilateral and bilateral ablation. Eyestalk ablation was done with a bistoury with a topic hot cauterization followed by application of antibiotic pomades. The animals were maintained at constant temperature (28 ± 1,05ºC) and photoperiod of 12L: 12D within fibercement boxes with sandy bottom and biological filter. Females were observed once a day during fourteen weeks, registering gonadal condition, ecdysis and presence of spermatophore (mating) and spawning. Unilateral ablation technique is more efficient due to the anticipation of the first spawn, repeatability between spawns, expressive rate of ovigerous females and survival, that favored its applicability. Bilateral eyestalk ablation produced the mortality of ali the females with change in coloration and food activity patterns. These results corroborate other observations on penaeid shrimps. though bilateral ablation on some lobsters was a success. These results showing an interespecific variation and can be used in aquaculture projects.

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Food habits and morpho-histology of the digestive tract of marbled swamp eel, Synbranchus marmoratus (Block, 1917) were investigated. The fish samples were captured during August, 2007 to July, 2008 in the Marechal Dutra reservoir, Acari, Rio Grande do Norte. The rain fall data was obtained from EMPARN. The fish captured, were measured, weighed, dissected, eviscerated and individual stomach weights were registered. The stomach contents analyses were carried out based on volumetric method, points, frequency of occurrence and applying the Index of Relative Importance. The degrees of repletion of the stomachs were determined besides the Index of Repletion relating to feeding activity variations and frequency of ingestion during the rainy and dry seasons. The rainfall varied from 0 mm a 335 mm with a mean value of 71.62 mm. Highest rainfall of 335.5 mm was registered in March, 2008 and August to December was the dry period. During the dry period the study species presented high degrees of repletion of the stomachs, with a peak value in the month of September (mean = 4.54; ± SD = 0.56). The minimum mean value of = 3.99 ± SD = 0.25 was registered in the month of May during the rainy period. The stomach contents of S. marmoratus registered show that this fish prefers animals, 78.22% of crustaceans 2.85% of mollusks, 3.25% of fish, 1.4% of insects and 13.5% of semi-digested organic matter, thus characterizing the study species as a carnivore with a preference for crustaceans. The morpho-histological aspects of the digestive tract of S. marmoratus indicate that the mouth is terminal adapted to open widely, thin lips with taste buds, small villiform teeth forming a single series on maxillas, four pairs of branchial arches with short and widely spaced branchial rays. The oesophagus is short and cylindrical with a small diameter. The oesophagus wall is thick with mucas surface and internal parallel folds. The stomach is retilinical in form, presenting cardiac, caecal and pyloric portions. The caecal portion is long and is intermediary in position between the cardiac and pyloric portions. The cardiac portion of the stomach is short and cylindrical formed of simple epithelial cylindrical mucus cells. The caecal portion is long with narrow walls, a big cavity and smaller folds which give rise to gastric glands. The phyloric portion has no glands and primary or secondary mucas folds. The morphohistological aspects of the digestive tract of S. marmoratus indicate its adaptation to a carnivorous feeding habit

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The feeding habits of two major species of sole, the common sole Solea vulgaris Quensel, 1806 and the Senegalese sole Solea senegalensis Kaup, 1858 were studied in the lower estuary of the Guadiana River (Algarve, southern Portugal). An evaluation of the number, weight, and feeding coefficient of prey types showed that S. vulgaris feed on a limited variety of prey (only Polychaeta and Tanaidacea) and present low-intensity feeding activity, with small differences in diet between seasons. S. senegalensis also have a low-diversity diet (with only one more taxa, Amphipoda), but exhibit more intense feeding activity which varies seasonally, although with little seasonal variation in the relative importance of the main preys. The diet composition of these two species suggests feeding specialization.

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The A1763 superstructure at z = 0.23 contains the first galaxy filament to be directly detected using mid-infrared observations. Our previous work has shown that the frequency of starbursting galaxies, as characterized by 24 mu m emission is much higher within the filament than at either the center of the rich galaxy cluster, or the field surrounding the system. New Very Large Array and XMM-Newton data are presented here. We use the radio and X-ray data to examine the fraction and location of active galaxies, both active galactic nuclei (AGNs) and starbursts (SBs). The radio far-infrared correlation, X-ray point source location, IRAC colors, and quasar positions are all used to gain an understanding of the presence of dominant AGNs. We find very few MIPS-selected galaxies that are clearly dominated by AGN activity. Most radio-selected members within the filament are SBs. Within the supercluster, three of eight spectroscopic members detected both in the radio and in the mid-infrared are radio-bright AGNs. They are found at or near the core of A1763. The five SBs are located further along the filament. We calculate the physical properties of the known wide angle tail (WAT) source which is the brightest cluster galaxy of A1763. A second double lobe source is found along the filament well outside of the virial radius of either cluster. The velocity offset of the WAT from the X-ray centroid and the bend of the WAT in the intracluster medium are both consistent with ram pressure stripping, indicative of streaming motions along the direction of the filament. We consider this as further evidence of the cluster-feeding nature of the galaxy filament.

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In order to assess the contribution of the thermogenic effect of feeding and muscular activity to total energy expenditure, nine premature infants were studied for 2 consecutive days during which time repeated measurements of energy expenditure by indirect calorimetry were performed throughout the day, combined with a visual activity score based on body movement. The infants were growing at 16.6 +/- 4.0 g/kg/day (mean +/- SD) and received 110 +/- 8 kcal/kg/day metabolizable energy (milk formula) and 522 +/- 40 mgN/kg/day. Their total energy expenditure was 68 +/- 4 kcal/kg/day indicating that 41 +/- 7 kcal/kg/day was retained for growth. Based on the combination of energy + N balances it was estimated that 80% of the weight gain was fat-free tissue and 20% was fat tissue. The rate of energy expenditure measured minute-by-minute was significantly and linearly correlated with the activity score in both the premeal (r = 0.75;p less than 0.001) and the postmeal periods (r = 0.74; p less than 0.001) with no difference in the regression slope, but with a significant difference in intercept. In preset feeding schedules the latter allowed an estimation of the thermogenic effect without the confounding effect of activity. This was found to be 3.1 +/- 1.8% when expressed as a percentage of metabolizable energy intake. However when the "classical" approach was used as a comparison (integration of extra energy expenditure induced by the meal), the thermogenic effect was found to be greater, i.e. 9.5 +/- 3.8% of the meal's metabolizable energy, due to the superimposed effect of physical activity in the postprandial state.(ABSTRACT TRUNCATED AT 250 WORDS)

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The objective of this work was to establish and test the induced-feeding bioassay in order to detect Bacillus thuringiensis insecticidal activity against Epilachna paenulata (Coleoptera: Coccinellidae). Larvae were induced to swallow high concentrations of spore-crystal suspensions of seven exotic and 30 Argentine B. thuringiensis strains. The great majority of strains showed no toxicity to E. paenulata larvae, and observed mortality was lower than 30%. Induced-feeding bioassay is feasible, and should be used for prospecting strains that produce right combinations of Cry proteins needed to an efficient pest control.

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The aim of the present study was to confirm whether feeding influences the resting breathing rate and to observe possible alterations in blood gas and pH levels produced by feeding in unanesthetized sloths (Bradypus variegatus). Five adult male sloths (4.1 ± 0.6 kg) were placed daily in an experimental chair for a period of at least 4 h for sitting adaptation. Five measurements were made for each sloth. However, the sloths one, two and five were studied once and the sloths three and four were studied twice. Breathing rate was determined with an impedance meter and the output signal was digitized. Arterial blood samples were collected for blood gas analysis with a BGE electrolytes analyzer and adjusted for the animal's body temperature and hemoglobin content. The data are reported as mean ± SD and were collected during the resting period (8:00-10:00 h) and during the feeding period (16:00-18:00 h). The mean breathing rate increased during mastication of ymbahuba leaves (rest: 5.0 ± 1, feeding: 10 ± 1 bpm). No significant alterations were observed in arterial pH (rest: 7.42 ± 0.05, feeding: 7.45 ± 0.03), PCO2 (rest: 35.2 ± 5.3, feeding: 33.3 ± 4.4 mmHg) or PO2 (rest: 77.5 ± 8.2, feeding: 78.4 ± 5.2 mmHg) levels. These results indicate that in unanesthetized sloths 1) feeding evokes an increase in breathing rate without a significant change in arterial pH, PCO2 or PO2 levels, and 2) the increase in breathing rate produced by feeding probably is due to the act of mastication.

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Heart rate (HR) and systolic (SBP), diastolic (DBP) and mean (MBP) blood pressure were recorded by biotelemetry in nine conscious unrestrained sloths for 1 min every 15 min over a 24-h period. The animals were allowed to freely move in an acoustically isolated and temperature-controlled (24 ± 1ºC) experimental room with light-dark cycle (12/12 h). Behavior was closely monitored through a unidirectional visor and classified as resting (sitting or suspended), feeding (chewing and swallowing embauba leaves, Cecropia adenops), or locomotor activity around the tree trunk or on the room floor. Locomotor activity caused statistically significant increases in SBP (+8%, from 121 ± 22 to 131 ± 18 mmHg), DBP (+7%, from 86 ± 17 to 92 ± 10 mmHg), MBP (+8%, from 97 ± 19 to 105 ± 12 mmHg), and HR (+14%, from 84 ± 15 to 96 ± 15 bpm) compared to resting values, indicating a possible major influence of the autonomic nervous system on the modulation of cardiac function during this behavior. During feeding, the increase in blood pressure was even higher (SBP +27%, from 119 ± 21 to 151 ± 21 mmHg; DBP +21%, from 85 ± 16 to 103 ± 15 mmHg; MBP +24%, from 96 ± 17 to 119 ± 17 mmHg), while HR remained at 14% (from 84 ± 15 to 96 ± 10 bpm) above resting values. The proportionally greater increase in blood pressure than in HR during feeding suggests an increase in peripheral vascular resistance as part of the overall response to this behavior.

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Patients with neurological disorders have an increased risk of oral and systemic diseases due to compromised oral hygiene. If patients lose the ability to swallow and chew food as a result of their disorder, enteral nutrition is often utilized. However, this type of feeding may modify salivary antioxidant defenses, resulting in increased oxidative damage and the emergence of various diseases. The aim of this study was to evaluate the effects of enteral nutrition on biochemical parameters in the unstimulated whole saliva composition of patients with neurological disorders. For this, enzymatic (superoxide dismutase - SOD; glutathione peroxidase - GPx) and non-enzymatic (uric acid; ferric ion reducing antioxidant power - FRAP) antioxidant activity, as well as a marker for oxidative damage (thiobarbituric acid reactive substances - TBARS) were analyzed. Unstimulated whole saliva was collected from 12 patients with neurological disorders and tube-feeding (tube-fed group - TFG), 15 patients with neurological disorders and normal feeding via the mouth (non-tube-fed group - NTFG), and 12 volunteers without neurological disorders (control group - CG). The daily oral hygiene procedures of TFG and NTFG patients were similar and dental care was provided monthly by the same institution's dentist. All patients exhibited adequate oral health conditions. The salivary levels of FRAP, uric acid, SOD, GPx, TBARS, and total protein were compared between studied groups. FRAP was increased (p < 0.05) in the NTFG (4651 +/- 192.5 mmol/mL) and the TFG (4743 +/- 116.7 mmol/mL) when compared with the CG (1844 +/- 343.8 mmol/mL). GPx values were lower (p < 0.05) in the NTGF (8.24 +/- 1.09 mmol/min/mg) and the TFG (8.37 +/- 1.60 mmol/min/mg) than in the CG (15.30 +/- 2.61 mmol/min/mg). Uric acid in the TFG (1.57 +/- 0.23 mg/dL) was significantly lower than in the NTFG (2.34 +/- 0.20 mg/dL) and the CG (3.49 +/- 0.21 mg/dL). Protein was significantly lower in the TFG (5.35 +/- 0.27 g/dL) than in the NTFG (7.22 +/- 0.57 g/dL) and the CG (7.86 +/- 0.54 g/dL). There was no difference in the salivary flow rate and SOD between groups. Enteral nutrition in patients with neurological disorders was associated with lower oxidative damage, resulting in increased salivary. antioxidant capacity. These results emphasize the importance of oral care for this population to prevent oral and systemic diseases. (C) 2014 Elsevier Ltd. All rights reserved.

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The objective of this study was to investigate whether increased dietary water content and feeding frequency increased voluntary physical activity of young, lean adult female cats. A replicated 4 x 4 Latin square design with a 2 x 2 factorial treatment arrangement (feeding frequency and water content) was used. The 4 treatments consisted of 1 meal daily dry pet food without added water (1D; 12% moisture as is), 1 meal daily dry pet food with added water (1W; 70% total water content), 4 meals daily dry pet food without added water (4D; 12% moisture as is), and 4 meals daily dry pet food with added water (4W; 70% total water content). Eight healthy adult, lean, intact, young, female domestic shorthair cats were used in this experiment. Voluntary physical activity was evaluated using Actical activity monitors placed on collars and worn around the cats'necks for the last 7 d of each experimental period of 14 d. Food anticipatory activity (FAA) was calculated based on 2 h prior to feeding periods and expressed as a percentage of total daily voluntary physical activity. Increased feeding frequency (4 vs. 1 meal daily) resulted in greater average daily activity (P = 0.0147), activity during the light period (P = 0.0023), and light: dark activity ratio (P = 0.0002). In contrast, physical activity during the dark period was not altered by feeding frequency (P > 0.05). Cats fed 4 meals daily had increased afternoon FAA (P = 0.0029) compared with cats fed once daily. Dietary water content did not affect any measure of voluntary physical activity. Increased feeding frequency is an effective strategy to increase the voluntary physical activity of cats. Thus, it may assist in the prevention and management of obesity.

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The present study was conducted to investigate the influence of restricted food access on Solea senegalensis behaviour and daily expression of clock genes in central (diencephalon and optic tectum) and pheripheral (liver) tissues. The Senegalese sole is a marine teleost fish belonging to the Class of Actinopterygii, Order Pleuronectiformes and Family Soleidae. Its geographical distribution in the Mediterranean sea is fairly broad, covering the south and east of the Iberian Peninsula, the North of Africa and Middle East until the coast of Turkey. From a commercial perspective Solea senegalensis has acquired in recent years, a key role in aquacolture industry of the Iberian Peninsula. The Senegalese sole is also acquiring an important relevance in chronobiological studies as the number of published works focused on the sole circadian system has increased in the last few years. The molecular mechanisms underlying sole circadian rhythms has also been explored recently, both in adults and developing sole. Moreover, the consideration of the Pleuronectiformes Order as one of the most evolved teleost groups make the Senegalese sole a species of high interest under a comparative and phylogenetic point of view. All these facts have reinforced the election of Senegalese sole as model species for the present study. The animals were kept under 12L:12D photoperiod conditions and divided into three experimental groups depending on the feeding time: fed at midlight (ML), middark (MD) or random (RND) times. Throughout the experiment, the existence of a daily activity rhythm and it synchronization to the light-dark and feeding cycles was checked. To this end locomotor activity was registred by means of two infrared photocells placed in pvc tube 10 cm below the water surface (upper photocell) and the other one was located 10 cm above the bottom of the tank (bottom photocell). The photocell were connected to a computer so that every time a fish interrupted the infrared light beam, it produced an output signal that was recorded. The number of light beam interruptions was stored every 10 minutes by specialized software for data acquisition.