Daily Feeding Cycle Research Articles

Implementasi Sistem Pemberian Pakan Ikan Hias Otomatis Menggunakan Esp32 Berbasis IoT (Internet of Things)

This study aims to design and implement an automatic feeding system for ornamental fish using Internet of Things (IoT) technology, with the ESP32 microcontroller and servo motor. Given Indonesia's extensive water resources and the importance of its fisheries sector, ornamental fish farming has gained significant popularity. Fish owners often struggle with providing timely and consistent feeding. IoT technology offers an effective solution through remote connectivity. The developed system utilizes the Blynk application to schedule and monitor aquarium conditions in real-time. Test results indicate that the integration of ESP32 and the servo motor functions effectively, enabling scheduled automatic feeding. The system was tested and found to operate punctually, supporting a consistent daily feeding cycle. This study contributes to the advancement of innovative solutions in aquaculture, particularly in the application of IoT technology for more efficient and effective aquarium management.

Sophistication in a seemingly simple creature: a review of wild holothurian nutrition in marine ecosystems.

ABSTRACTHolothurians are marine invertebrates that are among the most widespread benthic megafauna communities by both biomass and abundance in shallow‐water and deep‐sea ecosystems, their functions supporting important ecological services worldwide. Despite their simple appearance as sea cucumbers, holothurians show a wide range of feeding practices. However, information on what and how these animals eat is scattered and potentially confusing. We provide a comprehensive review of holothurian nutrition in coastal and deep‐sea ecosystems. First, we describe morphological aspects of holothurian feeding and the ultrastructure of tentacles. We discuss the two processes for food capture, concluding that mucus adhesion is likely the main method; two mucous cells, type‐1 and type‐2, possibly allow the adhesion and de‐adhesion, respectively, of food particles. Secondly, this review aims to clarify behavioural aspects of holothurian suspension‐ and deposit‐feeding. We discuss the daily feeding cycle, and selective feeding strategies. We conclude that there is selectivity for fine and organically rich particles, and that feeding through the cloaca is also a route for nutrient absorption. Third, we provide a wide description of the diet of holothurians, which can be split into two categories: living and non‐living material. We suggest that Synallactida, Molpadida, Persiculida, Holothuriida and Elasipodida, ingest the same fractions, and emphasise the importance of bacteria in the diet of holothurians.

Pollutant removal employing tidal flow constructed wetlands: Media and feeding strategies

Six partially saturated and unsaturated tidal flow constructed wetlands (TFCWs) were studied for the removal of nitrogen, phosphorus and organics from municipal wastewater. The TFCWs were packed with organic (biochar, coal, coco-peat), waste (slag), construction (gravel, concrete block) materials and planted with Phragmites or Vetiver. Daily wastewater feeding cycle was divided into sub-cycles across all TFCWs. Experimental analyses illustrated higher nitrogen and organics removals in organic media based TFCWs (71–85% and 84–96%, respectively), when compared with those of waste, construction material based units (49–69% and 74–95%, respectively); carbon availability from organic materials increased denitrification that was also supported by energy dispersive spectroscopy (EDS) analyses. Construction and waste material based TFCWs achieved better P removals (≥93%); Ca/Al/Fe ingredients of such materials allowed P removal via adsorption. Increment of wastewater contact period inside the media triggered physico-chemical and microbial removal routes. Partially saturated coal packed TFCW was the most efficient unit in terms of N removal percentage; presence of stationary water volume created anoxic environment and reduced input load, thereby improving removal performances. In terms of removal rates (g/m2 d), unsaturated TFCWs showed higher removal (over partially saturated units), which could be linked with greater input load. Mass balance analyses indicated ≤3% N removal through plant uptake; variation of plant species did not influence N removal. Therefore, observed removal kinetics was governed by adsorption and microbial routes. The results of this study suggest that, feeding sub-cycles could improve pollutant removals in TFCWs when packed with specific media.

Circadian Clock's Cancer Connections

The circadian molecular clock regulates and coordinates cellular metabolism with the organism's daily feeding and fasting cycle. Disruption of circadian rhythm, such as through jet lag or shift work, appears to heighten cancer risk in humans and accelerates tumorigenesis in animal models. The mammalian clock is a circuitry of transcription factors anchored by BMAL1-CLOCK, which drives diurnal oscillation of metabolic gene expression. The clock is independent of the cell cycle, but they can couple to coordinate normal cell proliferation. Expression of components of the clock, BMAL1 and PER2, appears decreased in human cancers. PER2 promotes p53 function, while BMAL1 expression is suppressed by MYC, linking key oncogenic drivers to the circadian clock. This review provides an overview of the clock, its regulation of metabolism, the connection to cancer shown in studies spanning from human epidemiology to cell biology, and the therapeutic implications of the circadian rhythm.

Modulation of peroxisome proliferator-activated receptor-α activity by bile acids causes circadian changes in the intestinal expression of Octn1/Slc22a4 in mice.

In addition to their digestive actions, bile acids modulate gene expression by altering the activity of peroxisome proliferator-activated receptor-α (PPARα). The modulatory effects of bile acids have been shown to affect the expression of genes responsible for lipid metabolism as well as membrane transporters. Bile acids are secreted in response to food intake and accumulate in intestinal epithelial cells. In the present study, we identified soluble carrier protein family 22 member 4 (Slc22a4), encoding organic cation transporter novel type-1 (Octn1), as a PPARα-regulated gene and its intestinal expression exhibited circadian oscillations in a bile acid-dependent manner. Nocturnally active mice mainly consumed their food around the early dark phase, during which bile acids accumulated in intestinal epithelial cells. PPARα activated the intestinal expression of Slc22a4 mRNA during the light period, and protein levels of Octn1 peaked before the start of the dark phase. The bile acids that accumulated in intestinal epithelial cells suppressed the PPARα-mediated transactivation of Slc22a4 in the dark phase. The time-dependent suppression of PPARα-mediated transactivation by bile acids regulated oscillations in the intestinal expression of Octn1/Slc22a4 during the daily feeding cycle. The results of a pharmacokinetic analysis also revealed that oscillations in the expression of Octn1 caused dosing time-dependent differences in the intestinal absorption of gabapentin (2-[1-(aminomethyl)cyclohexyl]acetic acid). These results suggest a molecular clock-independent mechanism by which bile acid-regulated PPARα activity governs the circadian expression of intestinal organic cation transporters. This mechanism could also account for interindividual variations in the pharmacokinetics of drugs that are substrates of Octn1.

Bile Acid-regulated Peroxisome Proliferator-activated Receptor-α (PPARα) Activity Underlies Circadian Expression of Intestinal Peptide Absorption Transporter PepT1/Slc15a1

Digested proteins are mainly absorbed as small peptides composed of two or three amino acids. The intestinal absorption of small peptides is mediated via only one transport system: the proton-coupled peptide transporter-1 (PepT1) encoded from the soluble carrier protein Slc15a1. In mammals, intestinal expression of PepT1/Slc15a1 oscillates during the daily feeding cycle. Although the oscillation in the intestinal expression of PepT1/Slc15a1 is suggested to be controlled by molecular components of circadian clock, we demonstrated here that bile acids regulated the oscillation of PepT1/Slc15a1 expression through modulating the activity of peroxisome proliferator-activated receptor α (PPARα). Nocturnally active mice mainly consumed their food during the dark phase. PPARα activated the intestinal expression of Slc15a1 mRNA during the light period, and protein levels of PepT1 peaked before the start of the dark phase. After food intake, bile acids accumulated in intestinal epithelial cells. Intestinal accumulated bile acids interfered with recruitment of co-transcriptional activator CREB-binding protein/p300 on the promoter region of Slc15a1 gene, thereby suppressing PPARα-mediated transactivation of Slc15a1. The time-dependent suppression of PPARα-mediated transactivation by bile acids caused an oscillation in the intestinal expression of PepT1/Slc15a1 during the daily feeding cycle that led to circadian changes in the intestinal absorption of small peptides. These findings suggest a molecular clock-independent mechanism by which bile acid-regulated PPARα activity governs the circadian expression of intestinal peptide transporter.

Changes in Glycogen Structure over Feeding Cycle Sheds New Light on Blood-Glucose Control

Liver glycogen, a highly branched polymer of glucose, is important for maintaining blood-glucose homeostasis. It was recently shown that db/db mice, a model for Type 2 diabetes, are unable to form the large composite glycogen α particles present in normal, healthy mice. In this study, the structure of healthy mouse-liver glycogen over the diurnal cycle was characterized using size exclusion chromatography and transmission electron microscopy. Glycogen was found to be formed as smaller β particles, and then only assembled into large α particles, with a broad size distribution, significantly after the time when glycogen content had reached a maximum. This pathway, missing in diabetic animals, is likely to give optimal blood-glucose control during the daily feeding cycle. Lack of this control may contribute to, or result from, diabetes. This discovery suggests novel approaches to diabetes management.

Applicability of short-term emission measurements for on-farm quantification of enteric methane

A short term enteric methane emission measurement is not identical to a measure of daily methane production (DMP) made in a respiration chamber (RC). While RC curtail most variation except that from quantity and composition of feed supplied, all short-term measurements contain additional sources of variation. The points of difference can include measurement time(s) relative to feeding, feed intake before measurement, animal behaviour in selection of diet and level of activity before measurement. For systems where a short-term emission measurement is made at the same time in the daily feeding cycle (e.g. during twice-daily milking) scaling up of short-term emission rates to estimate DMP is feasible but the scaling coefficient(s) will be diet dependent. For systems such as GreenFeed where direct emission rates are measured on occasion throughout day and night, no scaling up may be required to estimate DMP. For systems where small numbers of emission measures are made, and there is no knowledge of prior feed intake, such as for portable accumulation chambers, scaling to DMP is not currently possible. Even without scaling up to DMP, short-term measured emission rates are adequate for identifying relative emission changes induced by mitigation strategies and could provide the data to support genetic selection of ruminants for reduced enteric emissions.

Effects of feeding schedule on locomotor activity rhythms and stress response in sea bream

Feeding cycles entrain biological rhythms, which enable animals to anticipate feeding times and so maximize food utilization and welfare. In this article, the effect of mealtime was investigated in two groups of sea bream ( Sparus aurata): one group received a single daily meal at random times during the light period (random daytime feeding, RDF), whereas the other group received the meal during the light period but at the same time (scheduled daytime feeding, SDF). All the fish showed diurnal behavior, although the SDF group showed a lower percentage of diurnalism (84.4% vs. 79.5% in RDF and SDF respectively) and developed food anticipatory activity some hours before the mealtime. In addition, the mean daily locomotor activity of the RDF group was significantly higher than that of the SDF group (3132 vs. 2654 counts/day, respectively). Although the mean weight differed between both groups on day 30 (115.7 g and 125.6 g in RDF and SDF respectively), these differences had disappeared by day 60. Plasma cortisol and glucose significantly differed in both groups (cortisol: 71.8 vs. 8.7 ng/ml, glucose: 53.7 vs. 43.8 mg/dl in RDF and SDF, respectively), whereas lactate did not differ significantly. The results obtained suggest that altering the feeding time (scheduled vs. random) affects the behavior and physiology of sea bream, indicating that a single daily feeding cycle (compared to random) is beneficial for fish welfare because they can prepare themselves for the forthcoming feed.

Physiological significance of a peripheral tissue circadian clock

Mammals have circadian clocks in peripheral tissues, but there is no direct evidence of their physiological importance. Unlike the suprachiasmatic nucleus clock that is set by light and drives rest-activity and fasting-feeding cycles, peripheral clocks are set by daily feeding, suggesting that at least some contribute metabolic regulation. The liver plays a well known role in glucose homeostasis, and we report here that mice with a liver-specific deletion of Bmal1, an essential clock component, exhibited hypoglycemia restricted to the fasting phase of the daily feeding cycle, exaggerated glucose clearance, and loss of rhythmic expression of hepatic glucose regulatory genes. We conclude that the liver clock is important for buffering circulating glucose in a time-of-day-dependent manner. Our findings suggest that the liver clock contributes to homeostasis by driving a daily rhythm of hepatic glucose export that counterbalances the daily cycle of glucose ingestion resulting from the fasting-feeding cycle.

Short Communication: Diurnal Profiles of Conjugated Linoleic Acids and Trans Fatty Acids in Ruminal Fluid from Cows Fed a High Concentrate Diet Supplemented with Fish Oil, Linseed Oil, or Sunflower Oil

Trans-18:1 and 18:2 isomer composition in ruminal fluid during the daily feeding cycle was examined in 3 cows fed a high concentrate diet (35:65) with 5% (DM basis) sunflower oil (SO), 5% linseed oil (LO), or 2.5% fish oil (FO) in a 3×3 Latin square with 3 4-wk periods. Grass hay and concentrate mixtures were fed at 0900, 1300, and 1700h daily. Ruminal fluid was collected at 0900, 1100, 1300, 1500, 1700, 2000, and 0000h. Feeding SO resulted in the greatest mean concentrations (% of total fatty acids) of trans10,cis12-18:2 and cis9,trans11-18:2. In particular, trans10,cis12-18:2 with SO was greater at 1500 (0.29%), 2000 (0.34%), and 0000h (0.25%) relative to 0900h (0.07%). Cis9,trans11-18:2 concentration increased from 0.47% at 0900h to a peak of 2.06% at 1100h; it remained greater than the percentage determined at 0900h at 1300 (1.4%) through 0000h (1.1%). Concentration of trans11,cis15-18:2 was greatest with LO, ranging from 3.3% (0900h) to a peak of 11.4% at 2000h. Mean trans10-18:1 concentration ranked by diet was SO>FO>LO. Peak trans10-18:1 with SO was observed at 1700h (14.9%) compared with 0900h (5.1%). Trans11-18:1 did not differ with diet or time. Stearic acid decreased over time with all diets reaching minimum concentrations at 1700 to 2000h relative to 0900h. Feeding FO, however, decreased mean 18:0 concentration 4-fold compared with LO or SO. The moderate effect on concentration of trans-18:1 coupled with accumulation of 18:2 intermediates and the decrease of 18:0 over time suggest that oils reduced the biohydrogenation of 18:2 isomers to trans-18:1.

The influence of age on gastro-oesophageal reflux: a re-appraisal of the DeMeester scoring system.

The statistical evaluation of the influence of age on the pattern of gastro-oesophageal reflux (GOR) identified by prolonged pH monitoring in asymptomatic subjects. Re-appraisal of the DeMeester scoring system for GOR. Prolonged pH monitoring was performed on 45 asymptomatic elderly adults with normal contrast oesophagogram, manometry and endoscopy. They included 36 males and nine females. The mean age was 66.6 years. The monitoring time ranged between 20 and 24 h, including one complete daily feeding cycle. GOR was defined as a reflux event with a pH of <4. The mean, standard deviation, kurtosis and skew were calculated for six parameters listed in the results. The mean values were compared with those of normal values determined by DeMeester et al. (in: Read NW, editor. Gastrointestinal motility: which test? 1989, pp. 43-52) from their study of 50 young healthy adults, and the t-test was applied to determine the statistical significance of differences. The 'null hypothesis' for each parameter was defined as 'the mean values of the elderly population are not statistically different from DeMeester's normal values'. The means (+/-SD) of six parameters studied in pH monitoring were as follows: supine reflux time as a percentage of total study time, 2.94+/-5.18%; upright reflux time as a percentage of total study time, 4.14+/-5.71%; total reflux time as a percentage of total study time, 3.5+/-4.38%; duration of longest reflux episode, 14.98+/-24.92 min; number of reflux episodes lasting >5 min, 1.76+/-2.75; total number of reflux episodes during study, 13.49+/-11.31. These results were significantly different from the normal values reported by DeMeester. In addition, the data for each individual parameter was grossly skewed, as well as kurtotic, which implied that the data did not represent a normally distributed population. Moreover, we believe that the equation used for calculation of the DeMeester score, is inappropriate. The null hypothesis is rejected as the mean values of these parameters in our group are significantly higher than those used as normal. This implies that the normal values defined by DeMeester would over-diagnose gastro-oesophageal reflux disease (GORD). Moreover, we have found that the formula used to calculate the DeMeester's score is not according to the principle it is based on. DeMeester's system scoring is therefore inappropriate.

Leptin, corticotropin-releasing hormone (CRH), and neuropeptide Y (NPY)in free-ranging pregnant bats.

Leptin, the product of the obese gene first identified in mice, restores fertility in obese mice, and accelerates puberty in mice. We hypothesized that leptin's putative role in reproduction may extend to pregnancy and lactation. Leptin levels were determined in Myotis lucifugus, the little brown bat, a free-ranging mammal with a seasonal breeding cycle. The present study shows that plasma levels of leptin progressively rise during pregnancy, supporting a potential role for leptin in the maintenancy of pregnancy. In contrast, leptin was significantly lower during lactation, a time when most mammals, including bats, demonstrate reduced fertility. In addition to its possible roles in reproduction, leptin appears important in regulation of energy balance. M. lucifugus spontaneously fasts for up to 16 h each day during the active season, which allowed us to test the hypothesis that acute fasting was associated with decreased leptin. Leptin was significantly lower in fasted (lactating) bats, compared to those that recently returned from nightly foraging. Although postprandial lactating bats had a significantly higher fat index than fasted bats, plasma leptin and body fat were not significantly correlated, and were only weakly correlated (r2 = 0.26) when both pregnant and lactating females were included in the analysis. Similar changes during pregnancy, lactation, and the daily feeding cycle were observed in the hypothalamic neuropeptide, corticotropin-releasing hormone (CRH), which is believed to play an important role in energy balance and reproduction. By contrast, neuropeptide Y (NPY) increased during pregnancy but did not change during fasting. These results suggest that leptin's putative role in reproduction may extend to pregnancy and lactation, and that spontaneous, acute fasting results in decreased circulating levels of leptin in M. lucifugus.

Continuous Recording of Uneaten Food Pellets and Demand-Feeding Activity: A New Approach to Studying Feeding Rhythms in Fish

The existence of feeding rhythms implies that fish would feed better during their preferred feeding phase but reject food at any other time. In the present paper, we tested the performance of a new device for continuously collecting and detecting uneaten food pellets. The device is basically made of two parts: a pellet collector placed just under the feeder and a decanter with a sensor attached to the bottom. When a food pellet was not eaten, it was rapidly collected and transferred to the decanter, where it was detected while dropping by an infrared sensor coupled to a microcomputer. To validate this system, five groups of fifteen sea bass, Dicentrachus labrax L., were maintained under natural conditions and subjected to a daily feeding cycle (feeding rate = 2.5% of body weight) consisting of three meals of one hour duration each (0800–0900 h, 1600–1700 h and 2400–0100 h). Uneaten pellets together with demand-feeding activity were simultaneously recorded. In addition to these test tanks, “natural” demand-feeding rhythms were also investigated in five groups of sea bass maintained under an ad lib self-feeding regime. In the test tanks, when submitted to the three meal feeding cycle, sea bass showed clear time preferences for feeding, since they fed mostly during the morning and afternoon, rejecting food at night. Consequently, the profile of uneaten pellets peaked at night but remained very low during daytime. This diurnal preference for feeding is consistent with the almost strict diurnal feeding rhythm found in the sea bass groups under ad lib self-feeding. These results revealed the usefulness of this device in estimating food utilization and its potential application in nutritional and chronobiological studies in fish.

Predominant periportal expression of the fructose 1,6-bisphosphatase gene in rat liver: dynamics during the daily feeding rhythm and starvation-refeeding cycle.

Expression of the gene of the key gluconeogenic enzyme fructose 1,6-bisphosphatase (FBPase) was studied in rat liver during the daily feeding cycle and during refeeding after starvation. Total abundance of FBPase mRNA could be quantified by Northern blotting analysis with a digoxigenin-labelled 40-mer oligonucleotide probe. The zonal localization could not be demonstrated by in situ hybridization under several varied conditions with the 32P-end-labelled oligonucleotide probably due to insufficient sensitivity but was demonstrated with a 35S-labelled cRNA probe; the latter was synthesized from a polymerase chain reaction (PCR)-amplified 751 bp cDNA fragment inserted into a pBluescript. During a normal 12:12 h day/night rhythm (darkness with feeding from 1900 to 0700 hours), the total amount of FBPase mRNA stayed almost the same throughout the whole day. After 60 h of starvation the FBPase mRNA level decreased from a maximum at 1800 hours by approximately one-third at the end of refeeding at 0700 hours. Both during the normal feeding rhythm, after 60 h of starvation and during refeeding, i.e. under all conditions, FBPase mRNA was predominantly distributed in the periportal zone. The results clearly show that the preferentially periportal distribution of the FBPase enzyme activity is controlled mainly at a pretranslational level.

Zonal expression of the glucokinase gene in rat liver. Dynamics during the daily feeding rhythm and starvation-refeeding cycle demonstrated by in situ hybridization.

The abundance and zonal distribution of glucokinase (GK) mRNA were studied in rat liver during a normal 12 h day/12 h night rhythm (dark from 1900 to 0700 hours) and during refeeding after 60 h of starvation. Zonation of GK gene expression was examined by in situ hybridization with a radiolabelled cRNA probe and GK mRNA abundance was determined by Northern blot analysis with a digoxigenin-labelled cRNA probe. GK mRNA appeared to be almost homogeneously distributed throughout the whole daily feeding cycle; yet it was predominantly localized in the perivenous and intermediate zone during refeeding after 60 h of starvation. During the daily feeding rhythm, the total amount of GK mRNA increased quickly with the beginning of the feeding period at 1900 hours reaching a maximum at midnight and then decreased continuously to a basal level at noon. Virtually no GK mRNA was detected after 60 h of starvation. Refeeding caused a rapid increase in GK mRNA to a maximum at 2400 hours followed by a decrease to approximately two-thirds of the maximum value at 0700 hours. If the homogeneous distribution of GK mRNA during the daily feeding rhythm was real rather than apparent because of too low a sensitivity of the cRNA probe, the present results suggest that during the normal circadian cycle the mainly perivenous distribution of GK enzyme activity and protein is regulated preferentially at a translational level. The findings clearly show that during refeeding after 60 h of starvation the GK distribution is controlled predominantly at a pretranslational level.

The diet of Patagonian hake Merluccius australis polylepis and its daily ration of Patagonian grenadier Macrouronus magellanicus

The diet of the Patagonian hake Merluccius australis polylepis in 1986 was determined by analysis of stomach samples collected from commercial trawl catches. The major prey items were Patagonian grenadier Macrouronus magellanicus and, to a lesser extent, southern blue whiting Micromesistius australis. Large (81–100 cm) hake are mainly piscivorous and consume more grenadier than smaller (51–80 cm) hake. The smaller hake feed both on fish and invertebrates. There was no difference by sex in terms of stomach contents. The daily feeding cycle was also investigated from samples collected during 1991. Hake feed principally on 1-, 2-, and 3-year-old grenadier, which they seem to catch mainly at night. The daily ration of grenadier was between 0,043 and 0,26 per cent of body mass (1,692–9,849 g). The results are similar to those for other hake species in terms of composition of the diet, daily feeding cycle and daily ration.

Feeding behaviour of the American plaice ( Hippoglossoides platessoides) on the southern Grand Bank of Newfoundland

This study shows that on the southern Grand Bank, the diet of American plaice between 40 and 55 cm long mainly consists of Ammodytes dubius and brittle stars; the third most important prey is Mallotus villosus. To analyse feeding intensity during a daily and annual cycle, we used three different indices: the mean weight fullness index, the percentage of empty stomachs and the daily ration. The daily feeding intensity shows maxima related to the kind of prey consumed. A. dubius is consumed in larger amounts late in the day, between 18.00 and 24.00 h; M. villosus and brittle stars are preyed upon more intensely between 12.00 and 18.00 h. The maximum feeding activity is in April, with a summer period of relatively high values, followed by autumn and winter when feeding intensity is low. The American plaice shows flexibility in its feeding behaviour which allows it to consume its prey in larger amounts when they are more accessible; this accessibility may be the cause of its daily and annual feeding cycle.

Sow behaviour in computerised feeding systems

Computerised dry sow feeding systems are becoming increasingly popular as an alternative to earlier husbandry systems, partly in order to overcome some of the welfare problems associated with tethered sow systems. In order to investigate the feeding behaviour of dry sows in such a system, to see whether it may give rise to any welfare problems of its own, an interface has been developed between a system with two feeding stations (Pig Code) and a microcomputer data collection system recording the amount of food eaten and the time and duration of every visit. Data collected over a 2°month period showed a regular diurnal variation in visits to feeding stations. A peak in visiting frequency coincided with the start of the daily feeding cycle at 07:05 a.m. (GMT). This was composed of a sharp rise in the frequency of non-feeding visits during the 2 h before the start of the feeding cycle, followed by an even sharper and more sustained increase in frequency of feeding visits when the new cycle started. The animals used the two feeding stations to unequal extents. The causes underlying these results have yet to be established. Strategies and Tactics in Foraging of the Eatable The Pursuit A.W. ILLIUS Department of Agriculture, University of Edinburgh, West Mains Road, Edinburgh EH9 3JG (Gt. Britain) ABSTRACT Optimal foraging theory provides a framework for the analysis of foraging behaviour. Foraging strategies are part of a hierarchy of strategic goals which contribute eventually to the lifetimeOptimal foraging theory provides a framework for the analysis of foraging behaviour. Foraging strategies are part of a hierarchy of strategic goals which contribute eventually to the lifetime

The effect of marihuana (Delta-9 tetrahydrocannabinol) on pregnancy in rat

Lifestyle and genetic perturbation of circadian rhythm can trigger the incidence and severity of metabolic diseases. Time-restricted feeding (TRF) regulates the circadian rhythm of food intake that protects against metabolic disorders induced by adverse nutrient intake. TRF also executes host metabolism from nutrient availability to optimize nutrient utilization. Circadian clock and nutrient-sensing pathways coordinate to regulate metabolic health through the feeding/fasting cycle. Concurrently, TRF imposes diurnal rhythm in nutrient utilization, thereby preserving cellular homeostasis. However, modulation of daily feeding and fasting periods calibrates the circadian clock, which protects against the lethal effects of nutrient imbalance on metabolism. Therefore, TRF also improves and restores metabolic rhythms that ultimately lead to better fitness by reversing the alteration in genotype-specific gene expression. The aim of this review was to summarize that TRF is an emerging dietary approach that maintains robust circadian rhythms in support of a steady daily feeding and fasting cycle. TRF also encourages the coordination between circadian clock components and nutrient-sensing pathways via molecular effectors that exert a protective role in the prevention of metabolic diseases.