Seasonal variation in amount of unabsorbed dietary carbohydrate from the intestine after breakfast in Japanese subjects

We previously showed that daytime dim-light exposure has a negative effect on the efficiency of dietary carbohydrate absorption in the evening, whereas evening-time dim-light exposure has a beneficial effect. These results suggest that seasonal changes in the environmental light may affect gastrointestinal activity, and that there might, therefore, be seasonal variation in the efficiency of dietary carbohydrate absorption from the intestine. In order to prove this hypothesis, we measured the amount of dietary carbohydrate unabsorbed from the intestine after a breakfast in healthy female Japanese subjects during the four seasons of the year. We estimated the amount of unabsorbed dietary carbohydrate by the breath hydrogen test, which measures the amount of hydrogen in exhaled air. A 6 g solution of lactosucrose, an indigestible trisaccharide, was used for comparison. Two groups of subjects, 12 subjects in Osaka and 14 subjects in Nagano, were studied in the winter (January to February), spring (April to May), summer (July to August), and autumn (October to November) of 2004. We found the following results: (1) In no season were there any significant differences between the two subgroups in the orocecal transit time of the breakfast and the lactosucrose solution. Nor were there any significant differences in the amount of unabsorbed dietary carbohydrate from the breakfast. (2) Using the pooled data of the total of 26 subjects, there was no significant seasonal variation in the orocecal transit time of the breakfast or the lactosucrose solution. (3) There was a significant seasonal variation in the amount of unabsorbed dietary carbohydrate from the breakfast. (4) The amount of unabsorbed dietary carbohydrate from the breakfast was largest in winter and smallest in autumn. Results in spring and in summer were similar and intermediate between those in winter and autumn. Post hoc multiple comparison tests showed that the amount of unabsorbed dietary carbohydrate in winter was significantly larger than in autumn. (5) In winter, the average ratio of the amount of unabsorbed dietary carbohydrate to the total amount of carbohydrate in the breakfast was about 12%; in autumn it was about 6%. These results clearly show that there is seasonal variation in the efficiency of intestinal dietary carbohydrate absorption among young female Japanese subjects.     

Seasonal Variation in Amount of Unabsorbed Dietary Carbohydrate from the Intestine after Breakfast in Japanese Subjects

We previously showed that daytime dim‐light exposure has a negative effect on the efficiency of dietary carbohydrate absorption in the evening, whereas evening‐time dim‐light exposure has a beneficial effect. These results suggest that seasonal changes in the environmental light may affect gastrointestinal activity, and that there might, therefore, be seasonal variation in the efficiency of dietary carbohydrate absorption from the intestine. In order to prove this hypothesis, we measured the amount of dietary carbohydrate unabsorbed from the intestine after a breakfast in healthy female Japanese subjects during the four seasons of the year. We estimated the amount of unabsorbed dietary carbohydrate by the breath hydrogen test, which measures the amount of hydrogen in exhaled air. A 6 g solution of lactosucrose, an indigestible trisaccharide, was used for comparison. Two groups of subjects, 12 subjects in Osaka and 14 subjects in Nagano, were studied in the winter (January to February), spring (April to May), summer (July to August), and autumn (October to November) of 2004. We found the following results: (1) In no season were there any significant differences between the two subgroups in the orocecal transit time of the breakfast and the lactosucrose solution. Nor were there any significant differences in the amount of unabsorbed dietary carbohydrate from the breakfast. (2) Using the pooled data of the total of 26 subjects, there was no significant seasonal variation in the orocecal transit time of the breakfast or the lactosucrose solution. (3) There was a significant seasonal variation in the amount of unabsorbed dietary carbohydrate from the breakfast. (4) The amount of unabsorbed dietary carbohydrate from the breakfast was largest in winter and smallest in autumn. Results in spring and in summer were similar and intermediate between those in winter and autumn. Post hoc multiple comparison tests showed that the amount of unabsorbed dietary carbohydrate in winter was significantly larger than in autumn. (5) In winter, the average ratio of the amount of unabsorbed dietary carbohydrate to the total amount of carbohydrate in the breakfast was about 12%; in autumn it was about 6%. These results clearly show that there is seasonal variation in the efficiency of intestinal dietary carbohydrate absorption among young female Japanese subjects.     

Seasonal variation in the amount of dietary carbohydrate not absorbed from the intestine after breakfast in elderly Japanese females

It was previously shown that there is seasonality in the amount of dietary carbohydrate not absorbed from the intestine after breakfast, the amount of carbohydrate in winter being significantly larger than that in autumn in young Japanese subjects. In order to investigate this phenomenon further, the experiment was repeated on 22 elderly Japanese female subjects (61-78 yrs of age) during the four seasons of the year. The amount of unabsorbed dietary carbohydrate by the breath hydrogen test, which measures the amount of hydrogen in exhaled air, was then esitmated. A 6 g solution of lactosucrose, an indigestible trisaccharide, was used for comparison. Two groups of subjects, 16 subjects in Osaka and 6 subjects in Nagano, were studied in the summer (July to August) and autumn (October to November) of 2005 and the winter (January to February) and spring (April to May) of 2006. The following results were found using the pooled data of the total of 22 subjects. With regard to the amount of breath hydrogen excretion of the lactosucrose solution, there was no significant difference between the four seasons. There was a significant seasonal change in the efficiency of dietary carbohydrate absorption from the intestine after breakfast. The percentage of total carbohydrate that was not absorbed was lowest in the spring and highest in the winter. A comparison of the results from studies on the elderly and young subjects revealed the percentage of total carbohydrate that was not absorbed in the elderly was significantly lower than in the young in the winter, spring, and summer. These results indicate that there is seasonal variation in the efficiency of dietary carbohydrate absorption from the intestine among elderly female Japanese subjects as well as young female Japanese subjects. They also suggest that the efficiency of dietary carbohydrate absorption from the intestine after breakfast is retained in these naturally active and healthy elderly subjects.     

Gastric myoelectrical activity in a population of healthy Croatian subjects

Myoelectrical activity of the stomach was estimated in healthy Croatian subjects using the latest multi-channel percutaneous electrogastrograph. The aim of the study was to determine normal values of gastric myoelectrical activity for the population of Croatia. The study included 120 healthy subjects of both sexes, various age groups, body mass index values, and mode of lead placement. The measurement was performed 60 min before and 60 min after test meal. The following parameters of gastric myoelectrical activity were analyzed: dominant frequency (DF, c/min); dominant frequency within normal range (DFNR, %); coefficient of variation for dominant frequency (CVDF); dominant strength (DS, mV); postprandial increase intensity in dominant strength (PPIIDS; %); bradygastria (c/min, %); tachygastria (c/min, %); and arrhythmia. DF for the study group as a whole was around 3 cpm, at the normal range midpoint, and all other parameters were within the normal limits. On postprandial measurement, the rate of arrhythmias showed a significant decline. Age was found to influence DF, CVDF and arrhythmia in preprandial but not in postprandial period, whereas sex influenced DF, DS and bradygastria in preprandial period, and DF, CVDF, PPIIDS and tachygastria in postprandial period. The mode of lead placement had no impact on the electrogastrographic parameters observed. The values of gastric myoelectrical activity recorded in healthy Croatian subjects were within the normal range of the values defined by previous studies across Europe.     

A Holistic View of Dietary Carbohydrate Utilization in Lobster: Digestion,Postprandial Nutrient Flux,and Metabolism

Crustaceans exhibit a remarkable variation in their feeding habits and food type, but most knowledge on carbohydrate digestion and utilization in this group has come from research on few species. The aim of this study was to make an integrative analysis of dietary carbohydrate utilization in the spiny lobster Panulirus argus. We used complementary methodologies such as different assessments of digestibility, activity measurements of digestive and metabolic enzymes, and post-feeding flux of nutrients and metabolites. Several carbohydrates were well digested by the lobster, but maize starch was less digestible than all other starches studied, and its inclusion in diet affected protein digestibility. Most intense hydrolysis of carbohydrates in the gastric chamber of lobster occurred between 2–6 h after ingestion and afterwards free glucose increased in hemolymph. The inclusion of wheat in diet produced a slow clearance of glucose from the gastric fluid and a gradual increase in hemolymph glucose. More intense hydrolysis of protein in the gastric chamber occurred 6–12 h after ingestion and then amino acids tended to increase in hemolymph. Triglyceride concentration in hemolymph rose earlier in wheat-fed lobsters than in lobsters fed other carbohydrates, but it decreased the most 24 h later. Analyses of metabolite levels and activities of different metabolic enzymes revealed that intermolt lobsters had a low capacity to store and use glycogen, although it was slightly higher in wheat-fed lobsters. Lobsters fed maize and rice diets increased amino acid catabolism, while wheat-fed lobsters exhibited higher utilization of fatty acids. Multivariate analysis confirmed that the type of carbohydrate ingested had a profound effect on overall metabolism. Although we found no evidence of a protein-sparing effect of dietary carbohydrate, differences in the kinetics of their digestion and absorption impacted lobster metabolism determining the fate of other nutrients.     

Comparison of carbohydrate digestion between Japanese and Polish healthy subjects

We have revealed that light environment affects digestion and absorption of dietary carbohydrates in the gastrointestinal tract. This experimental result supposes that the efficiency of carbohydrate absorption may differ among people who live in different latitudes, such as Japanese and Polish people, at the same calendar season. In order to prove this hypothesis, we have been comparing the efficiency of carbohydrate absorption using the breath hydrogen test in Japan and Poland. Here, we report the comparison of the result obtained in the summer of 2004 as the following; (1) Orocecal transit time (OCTT) for indigestible trisaccharide of Japanese subjects was significantly longer than that in Poland (p = 0.043). (2) On the ingestion of minestrone, the amount of unabsorbed carbohydrate of Japanese subjects (which was estimated as trisaccharide equivalent) was significantly larger than that of Polish subjects (p = 0.006).     

Abnormal gastric slow waves in patients with functional dyspepsia assessed by multichannel electrogastrography

The aim of this study was to utilize multichannel electrogastrography to investigate whether patients with functional dyspepsia had impaired propagation or coordination of gastric slow waves in the fasting state compared with healthy controls. The study was performed in 10 patients with functional dyspepsia and 11 healthy subjects. Gastric myoelectrical activity was measured by using surface electrogastrography with a specially designed four-channel device. The study was performed for 30 min or more in the fasting state. Special computer programs were developed for the computation of the propagation and coupling of the gastric slow wave. It was found that, compared with the healthy controls, the patients showed a significantly lower percentage of slow wave propagation (58.0 +/- 8.9 vs. 89.9 +/- 2.6%, P < 0.002) and a significantly lower percentage of slow wave coupling (46.9 +/- 4.4 vs. 61.5 +/- 6.9%, P < 0.04). In addition, the patients showed inconsistencies in the frequency and regularity of the gastric slow wave among the four-channel electrogastrograms (EGGs). It was concluded that patients with functional dyspepsia have impaired slow wave propagation and coupling. Multichannel EGG has more information than single-channel EGG for the detection of gastric myoelectrical abnormalities.     

The impact of age, sex, body mass index and menstrual cycle phase on gastric myoelectrical activity characteristics in a healthy Croatian population

The aim of the study was to determine the impact of demographic and anthropometric parameters on the gastric myoelectrical activity characteristics in a healthy Croatian population. The influence of age, sex, body mass index (BMI) and menstrual cycle phase on the gastric myoelectrical activity characteristics was assessed. The study included 120 healthy subjects of both sexes (60 male and 60 female), divided into four age groups (18-35, 36-50, 51-65 and > 65 years) and three BMI groups (BMI < 25, 25-30 and > 30). Female subjects of reproductive age were divided into three groups according to menstrual cycle phase (day 1-3, day 4-8 and day 9-20 of menstruation). All study subjects underwent percutaneous electrogastrography (EGG) for 60 min before and 60 min after a test meal. The following parameters of the gastric myoelectrical activity were observed: dominant frequency (DF); dominant frequency within normal range (DFNR, %); coefficient of variation for dominant frequency (CVDF); dominant strength (DS. mV); postprandial increase intensity in dominant strength (PPIIDS, %); bradygastria (BG, c/min, %); tachygastria (TG, c/min, %); and arrhythmia (AR). Age was found to influence preprandial but not postprandial DFNR, CVDF and AR. Sex influenced preprandial DF, CVDF, DS and BG, and postprandial DF, CVDF, PPIIDS and TG. BMI exerted an impact on preprandial TG and AR, and postprandial DF, CVDF and AR. The phase of menstrual cycle influenced DF in preprandial period and none of EGG parameters in postprandial period.     

Seasonal Variation in the Amount of Dietary Carbohydrate Not Absorbed from the Intestine after Breakfast in Elderly Japanese Females

It was previously shown that there is seasonality in the amount of dietary carbohydrate not absorbed from the intestine after breakfast, the amount of carbohydrate in winter being significantly larger than that in autumn in young Japanese subjects. In order to investigate this phenomenon further, the experiment was repeated on 22 elderly Japanese female subjects (61–78 yrs of age) during the four seasons of the year. The amount of unabsorbed dietary carbohydrate by the breath hydrogen test, which measures the amount of hydrogen in exhaled air, was then esitmated. A 6 g solution of lactosucrose, an indigestible trisaccharide, was used for comparison. Two groups of subjects, 16 subjects in Osaka and 6 subjects in Nagano, were studied in the summer (July to August) and autumn (October to November) of 2005 and the winter (January to February) and spring (April to May) of 2006. The following results were found using the pooled data of the total of 22 subjects. With regard to the amount of breath hydrogen excretion of the lactosucrose solution, there was no significant difference between the four seasons. There was a significant seasonal change in the efficiency of dietary carbohydrate absorption from the intestine after breakfast. The percentage of total carbohydrate that was not absorbed was lowest in the spring and highest in the winter. A comparison of the results from studies on the elderly and young subjects revealed the percentage of total carbohydrate that was not absorbed in the elderly was significantly lower than in the young in the winter, spring, and summer. These results indicate that there is seasonal variation in the efficiency of dietary carbohydrate absorption from the intestine among elderly female Japanese subjects as well as young female Japanese subjects. They also suggest that the efficiency of dietary carbohydrate absorption from the intestine after breakfast is retained in these naturally active and healthy elderly subjects.     

Effect of postprandial posture on digestion and absorption of dietary carbohydrate

The effect of postprandial body posture on digestion and absorption of dietary carbohydrate were examined through breath hydrogen test on 6 female subjects. During the experiment, the participants either sat on a chair or lay on their backs for the first 4 hr (from 08:00 to 12:00) after eating the test breakfast meal. They then remained sedentary on a sofa for 6 hr (12:00 to 18:00). Participants' end alveolar breath samples were collected for 10 hr (every 15 min from 08:00 to 12:30, and then every 30 min until 18:00). The experiment was conducted on two consecutive days using a randomized, crossover study design. The results demonstrated that in the supine position orocecal transit time of the test meal was significantly slower than in the sitting position (260 +/- 21 min and 238 +/- 20 min, respectively, p < 0.01). In addition, afternoon breath hydrogen excretion due to a partial malabsorption of dietary carbohydrate and its fermentation in the colon was significantly larger in the sitting position (144.0 +/- 24.1 ppm.hr) than in the supine position (110.0 +/- 26.1 ppm.hr, p < 0.05). These results support the hypothesis that there was a marked effect of postprandial body posture on the function of the digestive system. The present findings suggest that the postprandial supine position is preferable to the sitting position for the digestion and absorption of dietary carbohydrate.     

Effects of dim or bright-light exposure during the daytime on human gastrointestinal activity

On the basis of our previous findings that bright-light exposure during the daytime has profound influence on physiological parameters such as melatonin secretion and tympanic temperature in humans, we proposed the hypothesis that bright vs. dim light-exposure during the daytime has a different influence on the activity of the digestive system via the endocrine and/or autonomic nervous system. To examine this hypothesis, we conducted a series of counterbalanced experiments in which subjects stayed the daytime (7:00 to 15:00h) under either a dim (80 lux) or bright (5,000 lux) light condition. We measured gastrointestinal activity using a breath hydrogen (indicative of carbohydrate malabsorption) and an electrogastrography (EGG, indicative of gastric myoelectric activity) test. The results showed the postprandial breath hydrogen excretion during the following nighttime period after daytime exposure to the dim-light condition was significantly higher than under the bright-light condition (p < 0.05). In addition, the spectrum total power of the EGG recorded after taking the evening meal was significantly lower for the dim than bright-light condition (p < 0.05). These results support our hypothesis and indicate that dim-light exposure during the daytime suppresses the digestion of the evening meal, resulting in malabsorption of dietary carbohydrates in it.     

Coenzyme Q10: absorption, tissue uptake, metabolism and pharmacokinetics

Available data on the absorption, metabolism and pharmacokinetics of coenzyme Q10 (CoQ10) are reviewed in this paper. CoQ10 has a fundamental role in cellular bioenergetics. CoQ10 is also an important antioxidant. Because of its hydrophobicity and large molecular weight, absorption of dietary CoQ10 is slow and limited. In the case of dietary supplements, solubilized CoQ10 formulations show enhanced bioavailability. The T_max is around 6 h, with an elimination half-life of about 33 h. The reference intervals for plasma CoQ10 range from 0.40 to 1.91 μmol/l in healthy adults. With CoQ10 supplements there is reasonable correlation between increase in plasma CoQ10 and ingested dose up to a certain point. Animal data show that CoQ10 in large doses is taken up by all tissues including heart and brain mitochondria. This has implications for therapeutic applications in human diseases, and there is evidence for its beneficial effect in cardiovascular and neurodegenerative diseases. CoQ10 has an excellent safety record.     

Effect of pepsin on partially purified pig gastric mucus and purified mucin

Partially purified native-pig gastric mucus and purified pig gastric mucin, prepared by column chromatography and caesium chloride (CsCl) density-gradient ultracentrifugation, were subjected to pepsin digestion. The products of peptic digestion were chromatographed on Sepharose CL-2B, and fractions were assayed for carbohydrate by the periodic acid-Schiff reaction. The polymeric gastric mucin in the purified mucin samples was readily degraded by pepsin. In sharp contrast, the polymeric mucin in the partially purified mucus was relatively resistant to pepsin digestion. In 45 min, pepsin degraded 40% of the polymeric mucin in the purified samples, whereas it produced no significant degradation (less than 10%) in the partially purified mucus samples. In partially purified gastric mucus, treated with CsCl but not fractionated by ultracentrifugation, digestion with pepsin was also slow and incomplete. This showed that differences in susceptibility between partially purified and purified preparations are not due to the chaotropic effects of CsCl. In addition, the recombination of low-density nonmucin fractions in CsCl ultracentrifugation with the mucin also resisted pepsin digestion. Finally, we have shown that the low-density fractions in mucus exhibited a strong inhibitory effect of peptic activity in vitro. We conclude that under our experimental conditions, pepsin has little effect on partially purified mucus, and our findings indicate an inhibitor of peptic digestion is present in native gastric mucus. It is likely, but unproven, that this inhibitor is a noncovalently bound lipid present in the low-density fraction.     

The pacemaker activity of interstitial cells of Cajal and gastric electrical activity

Interstitial cells of Cajal (ICC) are the pacemaker cells in the gut. They have special properties that make them unique in their ability to generate and propagate slow waves in gastrointestinal muscles. The electrical slow wave activity determines the characteristic frequency of phasic contractions of the stomach, intestine and colon. Slow waves also determine the direction and velocity of propagation of peristaltic activity, in concert with the enteric nervous system. Characterization of receptors and ion channels in the ICC membrane is under way, and manipulation of slow wave activity markedly alters the movement of contents through the gut. Gastric myoelectrical slow wave activity produced by pacemaker cells (ICC) can be reflected by electrogastrography (EGG). Electrogastrography is a perspective non-invasive method that can detect gastric dysrhythmias associated with symptoms of nausea or delayed gastric emptying.     

Effect of ghrelin on gastric myoelectric activity and gastric emptying in rats

Ghrelin is a recently discovered peptide in the endocrine cells of the stomach, which may stimulate gastric motility via the vagal nerve pathway. However, the mechanism of ghrelin-induced changes in gastrointestinal motility has not been clearly defined. The purpose of this study was to investigate the pharmacological effects of ghrelin on gastric myoelectrical activity and gastric emptying in rats, and to investigate whether cholinergic activity is involved in the effects of ghrelin. The study was performed on Sprague-Dawley rats implanted with serosal electrodes for electrogastrographic recording. Gastric slow waves were recorded from fasting rats at baseline and after injection of saline, ghrelin, atropine, or atropine+ghrelin. Gastric emptying of non-caloric liquid was measured by the spectrophotometric method in conscious rats. Intravenous administration of rat ghrelin (20 microg/kg) increased not only dominant frequency, dominant power and regularity of the gastric slow wave but also the gastric emptying rate when compared with the control rats (P<0.01, P<0.05, P<0.05, P<0.001 respectively). These stimulatory actions of ghrelin on both gastric myoelectrical activity and gastric emptying were not fully eliminated by pretreatment with atropine sulphate. These results taken together suggest that ghrelin may play a physiological role in the enteric neurotransmission controlling gastric contractions in rats.     

Dietary Resistant Starch Reduces Levels of Glucose-Dependent Insulinotropic Polypeptide mRNA along the Jejunum-Ileum in Both Normal and Type 2 Diabetic Rats

It has been reported that the circulating glucose-dependent insulinotropic polypeptide (GIP) levels were reduced by an intake of some foods/drugs capable of delaying carbohydrate digestion/absorption. In this study, we revealed that feeding rats with dietary resistant starch reduced the GIP mRNA levels along the entire length of the jejunoileum in both Wistar and type 2 diabetic GK rats.     

Dietary resistant starch reduces levels of glucose-dependent insulinotropic polypeptide mRNA along the jejunum-ileum in both normal and type 2 diabetic rats

It has been reported that the circulating glucose-dependent insulinotropic polypeptide (GIP) levels were reduced by an intake of some foods/drugs capable of delaying carbohydrate digestion/absorption. In this study, we revealed that feeding rats with dietary resistant starch reduced the GIP mRNA levels along the entire length of the jejunoileum in both Wistar and type 2 diabetic GK rats.     

Seasonal variation in effect of spa therapy on chronic pain

This study sought to investigate whether the effects of spa therapy are subject to seasonal variation as suggested by conventional spa therapy research. A total of 268 female (age 31-90 yr) and 119 male (age 35-85 yr) patients with noninflammatory chronic pain were studied. Patients stayed at an Austrian spa for 3 wk and received 2-4 treatments per day, including mudpacks, massages, and exercise therapy. In different groups of patients for 2 yr, pain (self-assessed by questionnaire and Likert scales) and associated variables (mood, fatigue) were measured at the beginning, end, and 6 wk after spa therapy. Data were analyzed by multivariate analysis of covariance controlling for possible group differences between seasons and cosinor analysis. The effect of spa therapy on pain was seasonally dependent; short-term decrease of pain was best between April and June and medium-term decrease of pain was best between October and November, with a second minor peak in fall and spring, respectively. The magnitude of the seasonal variation was greater for back (∼30%) than for joint (∼20%) pain. Positive mood also improved most between April and June. The observed semi-annual variations of pain do not correspond to the well-known annual change in many physiological and psychological variables. The results suggest that the effects of spa therapy and possibly other related treatments, such as physical and alternative therapies, are subject to seasonal variation.     

Noninvasive assessment of the effects of glucagon on the gastric slow wave

Hyperglycemic effects on the gastric slow wave are not well understood, and no studies have examined the effects that hyperglycemia has on gastric slow wave magnetic fields. We recorded multichannel magnetogastrograms (MGGs) before and after intravenous administration of glucagon and subsequent modest hyperglycemia in 20 normal volunteers. Normal slow waves were evident in baseline MGG recordings from all 20 subjects, but within 15 min after glucagon had been given, we noted significant effects on MGG signals. In addition to an overall decrease in the slow wave frequency from 2.9 +/- 0.5 cycles per min (cpm) to 2.2 +/- 0.1 cpm (P < 0.05), we observed significant changes in the number and range of spectral peaks recorded. Furthermore, the propagation velocity determined from surface current density maps computed from the multichannel MGG decreased significantly (7.1 +/- 0.8 mm/s to 5.0 +/- 0.3 mm/s, P < 0.05). This is the first study of biomagnetic effects of hyperglycemia in normal subjects. Our results suggest that the analysis of the MGG provides parameter quantification for gastric electrical activity specific to and characteristic of slow wave abnormalities associated with increased serum glucose by injection of glucagon.     

Dietary digestibility and the influence of food components on gastric evacuation in plaice, Pleuronectes platessa L.

Digestibility values are reported for a variety of diets fed to plaice. It was found that animal proteins were digested better than those from plant sources and the inclusion of indigestible carbohydrate (starch) led to a decrease in the efficiency of digestion and absorption of protein. The results of the digestibility trials were used to investigate the influence of various dietary parameters on gastric emptying and it was found that the gross energy content of the diet was the most important determinant of evacuation. The findings are examined in relation to published data on food intake by fishes and the implications discussed.