Restricted Feeding Regime Research Articles

Circadian-driven tissue specificity is constrained under caloric restricted feeding conditions

Tissue specificity is a fundamental property of an organ that affects numerous biological processes, including aging and longevity, and is regulated by the circadian clock. However, the distinction between circadian-affected tissue specificity and other tissue specificities remains poorly understood. Here, using multi-omics data on circadian rhythms in mice, we discovered that approximately 35% of tissue-specific genes are directly affected by circadian regulation. These circadian-affected tissue-specific genes have higher expression levels and are associated with metabolism in hepatocytes. They also exhibit specific features in long-reads sequencing data. Notably, these genes are associated with aging and longevity at both the gene level and at the network module level. The expression of these genes oscillates in response to caloric restricted feeding regimens, which have been demonstrated to promote longevity. In addition, aging and longevity genes are disrupted in various circadian disorders. Our study indicates that the modulation of circadian-affected tissue specificity is essential for understanding the circadian mechanisms that regulate aging and longevity at the genomic level.

Physiological and immunological aspects of feed restriction and its beneficial impacts in fattening rabbits' productivity-an updated review.

Two feed restriction (FR) regimens are utilized with weaned rabbits including a quantitative FR (amount-limited feed or time-restricted admission to feed) and a qualitative FR (modulation of diet content especially protein and energy). The use of post-weaning FR may help in preventing post-weaning digestive disorders, stimulating compensating growth, improving feed efficiency, and decreasing carcass fat content. Interestingly, FR may contribute to changing meat's chemical composition and its physical quality attributes by regulating the morphological and biochemical characteristics of muscle fibers. Also, FR could enhance the gastrointestinal tract development, its histomorphology, and improve feed digestibility and absorption. Furthermore, FR regimens are involved in establishing gut microbial balance and enhancing the host immunological response. It might be concluded that post-weaning FR is involved in influencing the physiological and immunological aspects of growing rabbits. It might be documented that light to mild FR (i.e., 80-90% AL), early (i.e., at the first 2 weeks post-weaning), and relatively short in duration (i.e., for 2-3 weeks) had no negative effects on live body weight, while severing FR reduced live body weight in comparison with ad libitum rabbits.

Strategies to combat heat stress in poultry production-A review.

The effects of heat stress (HS) caused by high temperatures continue to be a global concern in poultry production. Poultry birds are homoeothermic, however, modern-day chickens are highly susceptible to HSdue to their inefficiency in dissipating heat from their body due to the lack of sweat glands. During HS, the heat load is higher than the chickens'ability to regulate it. This can disturb normal physiological functioning, affect metabolismand cause behavioural changes, respiratory alkalosis and immune dysregulation in birds. These adverse effects cause gut dysbiosis and, therefore, reduce nutrient absorption and energy metabolism. Thisconsequentlyreduces production performances and causes economic losses. Several strategies have been explored to combat the effects of HS. These include environmentally controlled houses, provision of clean cold water, low stocking density, supplementation of appropriate feed additives, dual and restricted feeding regimes, early heat conditioningand genetic selection of poultry lines to produce heat-resistant birds. Despite all these efforts, HS still remains a challenge in the poultry sector. Therefore, there is a need to explore effective strategies to address this long-lasting problem. The most recent strategy to ameliorate HS in poultry is early perinatal programming using the in ovo technology. Such an approach seems particularly justified in broilers because chick embryo development (21 days) equals half of the chickens'posthatch lifespan (42 days). As such, this strategy is expected to be more efficient and cost-effective to mitigate the effects of HS on poultry and improve the performance and health of birds. Therefore, this review discusses the impact of HS on poultry, the advantages and limitations of the different strategies. Finally recommend a promising strategy that could be efficient in ameliorating the adverse effects of HS in poultry.

Partial and total replacement of soybean meal with a corn‐fermented protein product in Rainbow Trout feeds

AbstractObjectiveCorn‐fermented protein products (CFP) from the bioethanol industry have strong potential as alternatives to traditional plant protein sources in finfish diets. This study examined the culture performance, apparent digestibility, intestinal histology, and expression of gut inflammation markers in juvenile Rainbow Trout Oncorhynchus mykiss fed experimental diets with graded levels of soybean meal and CFP.MethodsFour experimental diets were formulated to contain 40% protein and 20% lipids, and the diets incrementally replaced soybean meal with CFP (0% [Control], 25%, 50%, or 100% replacement). Juvenile Rainbow Trout (48.9 ± 1.3 g) were randomly distributed to 12 100‐L tanks within a recirculating aquaculture system (30 fish/tank). Fish were fed one of the four experimental diets on a restricted feeding regime (1–3% biomass/day), and tanks were weighed every 14 days for 70 days.ResultThe mean weight, specific growth rate, feed conversion ratio, survival, and proximate composition of fish were not significantly different (α = 0.05) between the diet groups after 70 days of feeding (139.6 ± 7.5 g final weight). Apparent protein digestibility was significantly higher in the 50% CFP diet group than the Control group (80.3 ± 1.2% and 77.6 ± 1.2%, respectively). Histological analysis of distal intestines showed significantly larger villi lengths and villi length‐to‐width ratios in fish fed the 100% CFP diet, relative to fish fed the Control and 25% CFP diets. The expression of gut inflammation markers tumor necrosis factor alpha (TNF‐α), interleukin (IL)10, and matrix metalloproteinase‐9 (MMP9) trended lower in the 50% and 100% CFP diet groups compared to the Control group. The expression of the nutrient absorption markers PepT1 and FABP2 trended higher in the 50% and 100% CFP diet groups relative to the Control group.ConclusionThe results of this study suggested that the replacement of soybean meal with CFP in Rainbow Trout grow‐out diets did not impair growth performance and improved overall protein digestibility and gut health.

Restricted feeding regimens improve white striping associated muscular defects in broiler chickens.

The current study investigated the effects of intermittent feeding (IF) and fasting strategies at different times post-hatch on muscle growth and white striping (WS) breast development. In the first trial, 32 one-day-old Abor Acre broilers were fed ad libitum (AL) for 3d post-hatch and then randomly allotted into 4 feeding strategies including AL, 1h-IF group (1h IF, 4 times feeding/d, 1h each time), 1.5h-IF (1.5h IF, 4 times feeding/d, 1.5h each time), and fasting (1d acute fasting, 6d free access to feed) groups and fed for 7d. Although angiogenic genes including VEGFA, VEGFR1, and VEGFR2, and myogenic genes including MYOG and MYOD were upregulated (P<0.05), the breast muscle satellite cell (SC) number and PAX7, MYF5 expression were decreased by the IF strategies (P<0.05). One-day fasting at 6d of age also upregulated angiogenic genes and MYOD expression (P<0.05), downregulated MYF5 expression (P<0.05), but did not change SC number (P>0.05). In the second trial, 384 one-day-old birds were fed AL for 1wk and then randomly allotted to the above 4 feeding strategies starting at 8d of age until 42d of age. Similarly, IF and fasting strategies upregulated the expression of angiogenic and myogenic genes (P<0.05). Both 1h-IF and 1.5h-IF increased breast muscle SC number (P<0.05). At slaughter, breast muscle fiber diameter of 1.5h-IF was smaller but the SC number was larger than that of the birds fed AL (P<0.05). The IF and fasting strategies prevented WS development, and reduced breast WS scores and triglyceride content (P<0.05) without changing the body weight (P>0.05). Fasting and 1h-IF reduced the expression of adipogenic genes ZNF423 and PDGFRα (P<0.05). Moreover, IF and fasting strategies reduced fibrosis in breast muscle and reduced skeletal muscle-specific E3 ubiquitin ligases (TRIM63 and MAFBX) (P<0.05). Fasting significantly reduced CASPASE-3 in breast muscle (P<0.05). In conclusion, IF starting in the first week decreases SC number. Compared to AL, IF or fasting promotes muscular angiogenesis, increases SC number, prevents muscle degeneration, and prevents the development of WS without impairing the growth performance of broiler chickens.

Abstract 094: Bmal1 Is Necessary For Food-Based Entrainment Of Blood Pressure And Temperature Rhythms In The Rat

Blood pressure (BP) follows a circadian rhythm, changing throughout the day. This change is crucial for cardiovascular health and in patient populations, as loss of these rhythms are associated with increased mortality and morbidity. Though BP rhythms have been recognized as important, the factors that control and entrain them are not well-described. Since the molecular clock is ubiquitously expressed in all cells and required for many circadian processes, we tested the hypothesis that the molecular clock contributes to the timing of BP rhythms in rats. Male and female rats with whole body loss of brain and muscle ARNTL-like protein ( Bmal1 ) and wild type (WT) controls (Sprague-Dawley background) were instrumented with telemeters in the abdominal aorta and placed in 12:12h light dark cycle (LD) to measure BP and core body temperature (TMP). Next, animals were placed in constant darkness (DD) for four weeks and then placed on a 12-hour time restricted feeding regimen (DD-TRF) for five days. Cosinor analysis was used to analyze BP and TMP rhythms. In a standard LD cycle, systolic BP (SBP) and TMP rhythms of both Bmal1 -knockout ( Bmal1- KO) and WT rats have similar amplitudes (2-way ANOVA for SBP and TMP, both p&gt;0.05) which peak around zeitgeber time (ZT)18. During DD, WTs have SBP and TMP rhythms peak at circadian time (CT)19, while Bmal1 -KO rats have SBP and TMP rhythms that peak at CT 12. SBP amplitude is lower in all groups during DD compared to LD (WT males: 6.0±0.7 vs 3.8±0.7 mmHg; WT females: 7.2±0.9 vs 5.6±0.3 mmHg; KO males: 5.4±0.6 vs 4.7±0.4 mmHg; KO females: 6.2±0.6 vs 5.3±0.8 mmHg; 3-way ANOVA, p&lt;0.05 for light cycle). During DD-TRF (CT 14.5 – 2.5), SBP and TMP rhythms of WTs peak at CT22. Bmal1 -KO rats have SBP and TMP rhythms that peak during CT16. SBP amplitude is lowered in Bmal1 -KO rats during DD-TRF compared to DD (KO males: 2.0±0.7 mmHg; KO females: 3.8±0.6 mmHg) but not in WT rats (WT males: 3.8±0.3 mmHg; WT females: 5.1±0.4 mmHg; 3-way ANOVA, p&lt;0.05 for feeding time, sex, and feeding time*genotype). These data suggest that the molecular clock component Bmal1 is necessary for food-based entrainment of SBP and temperature rhythms in the absence of a regular light cue. Food, light cycle, and the molecular clock may all contribute to the timing and amplitude of SBP and TMP rhythms.

Misaligned feeding schedule elicits divergent circadian reorganizations in endo- and exocrine pancreas clocks.

Misaligned feeding may lead to pancreatic insufficiency, however, whether and how it affects circadian clock in the exocrine pancreas is not known. We exposed rats to a reversed restricted feeding regimen (rRF) for 10 or 20days and analyzed locomotor activity, daily profiles of hormone levels (insulin, glucagon, and corticosterone) in plasma, and clock gene expression in the liver and endocrine and exocrine pancreas. In addition, we monitored responses of the exocrine pancreatic clock in organotypic explants of mPer2Luc mice in real time to acetylcholine, insulin, and glucocorticoids. rRF phase-reversed the clock in the endocrine pancreas, similar to the clock in the liver, but completely abolished clock gene rhythmicity and significantly downregulated the expression of Cpb1 and Cel in the exocrine pancreas. rRF desynchronized the rhythms of plasma insulin and corticosterone. Daily profiles of their receptor expression differed in the two parts of the pancreas and responded differently to rRF. Additionally, the pancreatic exocrine clock responded differently to treatments with insulin and the glucocorticoid analog dexamethasone in vitro. Mathematical simulation confirmed that the long-term misalignment between these two hormonal signals, as occurred under rRF, may lead to dampening of the exocrine pancreatic clock. In summary, our data suggest that misaligned meals impair the clock in the exocrine part of the pancreas by uncoupling insulin and corticosterone rhythms. These findings suggest a new mechanism by which adverse dietary habits, often associated with shift work in humans, may impair the clock in the exocrine pancreas and potentially contribute to exocrine pancreatic insufficiency.

Intermittent fasting induces chronic changes in the hepatic gene expression of Red Jungle Fowl (Gallus gallus)

BackgroundIntermittent fasting (IF), the implementation of fasting periods of at least 12 consecutive hours on a daily to weekly basis, has received a lot of attention in recent years for imparting the life-prolonging and health-promoting effects of caloric restriction with no or only moderate actual restriction of caloric intake. IF is also widely practiced in the rearing of broiler breeders, the parent stock of meat-type chickens, who require strict feed restriction regimens to prevent the serious health problems associated with their intense appetites. Although intermittent fasting has been extensively used in this context to reduce feed competition and its resulting stress, the potential of IF in chickens as an alternative and complementary model to rodents has received less investigation. In both mammals and birds, the liver is a key component of the metabolic response to IF, responding to variations in energy balance. Here we use a microarray analysis to examine the liver transcriptomics of wild-type Red Jungle Fowl chickens fed either ad libitum, chronically restricted to around 70% of ad libitum daily or intermittently fasted (IF) on a 2:1 (2 days fed, 1 day fasted) schedule without actual caloric restriction. As red junglefowl are ancestral to domestic chicken breeds, these data serve as a baseline to which existing and future transcriptomic results from farmed birds such as broiler breeders can be compared.ResultsWe find large effects of feeding regimen on liver transcriptomics, with most of the affected genes relating to energy metabolism. A cluster analysis shows that IF is associated with large and reciprocal changes in genes related to lipid and carbohydrate metabolism, but also chronic changes in genes related to amino acid metabolism (generally down-regulated) and cell cycle progression (generally up-regulated). The overall transcription pattern appears to be one of promoting high proliferative plasticity in response to fluctuations in available energy substrates. A small number of inflammation-related genes also show chronically changed expression profiles, as does one circadian rhythm gene.ConclusionsThe increase in proliferative potential suggested by the gene expression changes reported here indicates that birds and mammals respond similarly to intermittent fasting practices. Our findings therefore suggest that the health benefits of periodic caloric restriction are ubiquitous and not restricted to mammals alone. Whether a common fundamental mechanism, for example involving leptin, underpins these benefits remains to be elucidated.

Effect of skip-feeding and re-feeding regimes on compensatory growth, body composition, feed utilization, feeding cost and survival of monosex tilapia (Oreochromis niloticus) in pond aquaculture system

Monosex tilapia has great acceptability particularly among the lower income people due to its lower price. However, due to increased feed price the price of tilapia has been increased in recent years. Compensatory growth (CG) of fish that is achieved after a period of feed deprivation can potentially reduce the feed cost. The present study aimed to get CG in tilapia farming so as to reduce the production cost of this popular fish. Tilapia fry of 0.54 g body weight were nursed in hapa for one month and then stocked in earthen ponds where two different restricted feeding regimes were imposed for next two months followed by one month feeding at satiation level. Sampling was done fortnightly to record average weight gain in control and treatment groups. Average individual weight in restricted feeding group (T1) reached to 170.11±4.6 g in a three months experimental period and it did not significantly (p&gt;0.05) differ with the weight gained in control group (182.79±5.32 g) where fish were fed on regular basis. The specific growth rate (SGR) also showed no significant difference (p&gt;0.05) between T1 (SGR 2.66±0.011 % day-1) and control group (SGR 2.69±0.012 % day-1). Feed Conversion Ratio (FCR) in T1 (1.26) was found significantly (p&lt;0.05) lower to that of control group (1.47), hence the per unit production cost was also found significantly lower in T1 (BDT 75 Kg-1) compared to that of control (BDT 88.23 Kg-1). On the other hand no significant difference was evident in biochemical parameters between the control and restricted feeding groups. Thus, this study suggests skip feeding as an appropriate tool to achieving CG in monosex tilapia and to trim down the production cost as well.&#x0D;

Effect of feed restriction on the maintenance energy requirement of broiler breeders.

ObjectiveThis study aimed to evaluate the effect of the ad libitum and restricted feeding regimen on fasting heat production (FHP) and body composition.MethodsTwelve Hubbard broilers breeders were selected with the same body weight and submitted in two feeding regimes: Restricted (T1) with feed intake of 150 g/bird/d and ad libitum (T2). The birds were randomly distributed on the treatments in two runs with three replications per treatment (per run). The birds were adapted to the feed regimens for ten days. After that, they were allocated in the open-circuit chambers and kept for three days for adaptation. On the last day, oxygen consumption (VO2) and carbon dioxide production (VCO2) were measured by 30 h under fasting. The respiratory quotient (RQ) was calculated as the VCO2/VO2 ratio, and the heat production (HP) was obtained using the Brower equation (1985). The FHP was estimated throughout the plateau of HP 12 hours after the feed deprivation. The body composition was analyzed by dual-energy X-ray absorptiometry scanning at the end of each period. Data were analyzed for one-way analysis of variance using the Minitab software.ResultsThe daily feed intake was 30 g higher to T2 (p<0.01) than the T1. Also, the birds of the T2 had significatively (p<0.05) more oxygen consumption (+3.1 L/kg0.75/d) and CO2 production (+2.2 L/kg0.75/d). That resulted in a higher FHP 359±14 kJ/kg0.75/d for T2 than T1 296±17.23 kJ/kg0.75/d. In contrast, the RQ was not different between treatments, with an average of 0.77 for the fasting condition. In addition, protein and fat composition were not affected by the treatment, while a tendency (p<0.1) was shown to higher bone mineral content on the T1.ConclusionThe birds under ad libitum feeding had a higher maintenance energy requirement but their body composition was not affected compared to restricted feeding.

Effect of different feed restriction regimens on performance, behaviors, blood cortisol, and carcass parameters of growing Sasso broilers.

The aim of this study was to evaluate the effect of different feed restriction regimens on performance, behavioral patterns, blood cortisol, and carcass parameters in Sasso broilers. Sixty healthy 1-day-old unsexed Sasso chicks were randomly assigned to three groups (20 chicks per group) and each group was divided into 4 replicates with 5 chicks each based on feed restriction program during the rearing period (60days). The first group (G1) is control in which birds were fed ad libitum had free access to feed (no restriction). The second group (G2) was subjected to temporary feed restriction at the first 2weeks as birds had access to feed for 12h only after that they had free access to feed until the end of the experimental period. The third one (G3) was subjected to continuous feed restriction as birds had free access to feed for 12h only throughout the rearing periods. During the study period, growth performance and behavioral patterns were estimated. At the end of the study, blood samples for cortisol testing were taken. Three birds from each group were slaughtered at the end of the study to see how the feed restriction affected carcass parameters. Feed restriction had a substantial impact (P ≤ 0.05) on final body weight and carcass parameters. Feed restriction elevated blood cortisol significantly (P = 0.004). Feed restriction showed a significant impact on some behaviors as feeding, stretching, preening, and aggression. Overall, different feed restriction programs had a wide effect on growth performance, behaviors, cortisol concentration, and carcass parameters of Sasso broilers.

Effect of Restricted Feeding on Metabolic Health and Sleep-Wake Rhythms in Aging Mice.

Aging, an irreversible and unavoidable physiological process in all organisms, is often accompanied by obesity, diabetes, cardiovascular diseases, sleep disorders, and fatigue. Thus, older adults are more likely to experience metabolic symptoms and sleep disturbances than are younger adults. Restricted feeding (RF) is a dietary regimen aimed at improving metabolic health and extending longevity, as well as reorganizing sleep-wake cycles. However, the potential of RF to improve metabolic health and sleep quality in older adults who are known to show a tendency toward increased weight gain and decreased sleep is unknown. To elucidate this issue, aged mice were assigned to an RF protocol during the active phase for 2 h per day for 2 weeks. Sleep-wake cycles were recorded during the RF regime in RF group and control mice. At the end of this period, body weight and blood biochemistry profiles, including blood glucose, cholesterol, and enzyme activity, in addition to dopamine concentrations in the brain, were measured in the RF group and age-matched controls. RF for 2 weeks improved the metabolic health of aged mice by reducing their body weights and blood glucose and cholesterol levels. At the beginning of the RF regime, sleep decreased in the dark period but not in the light period. After stable food entrainment was achieved (7 days post-RF commencement), the amount of time spent in wakefulness during the light period dramatically increased for 2 h before food availability, thereby increasing the mean duration of awake episodes and decreasing the number of wakefulness episodes. There was no significant difference in the sleep-wake time during the dark period in the RF group, with similar total amounts of wakefulness and sleep in a 24-h period to those of the controls. During the RF regime, dopamine levels in the midbrain increased in the RF group, pointing to its potential as the mechanism mediating metabolic symptoms and sleep-wake regulation during RF. In conclusion, our study suggested that RF during aging might prohibit or delay the onset of age-related diseases by improving metabolic health, without having a severe deleterious effect on sleep.

Modulatory Effect of Intermittent Fasting on Adipose Tissue Inflammation: Amelioration of Cardiovascular Dysfunction in Early Metabolic Impairment.

Cardiometabolic syndrome (CMS) is a cluster of maladaptive cardiovascular, renal, thrombotic, inflammatory, and metabolic disorders. It confers a high risk of cardiovascular mortality and morbidity. CMS is triggered by major shifts in lifestyle and dietary habits with increased consumption of refined, calorie-dense diets. Evidence indicates that diet-induced CMS is linked to Adipose tissue (AT) inflammation. This led to the proposal that adipose inflammation may be involved in metabolic derangements, such as insulin resistance and poor glycemic control, as well as the contribution to the inflammatory process predisposing patients to increased cardiovascular risk. Therefore, in the absence of direct pharmacological interventions for the subclinical phase of CMS, time restricted feeding regimens were anticipated to alleviate early metabolic damage and subsequent comorbidities. These regimens, referred to as intermittent fasting (IF), showed a strong positive impact on the metabolic state of obese and non-obese human subjects and animal models, positive AT remodeling in face of overnutrition and high fat diet (HFD) consumption, and improved CV outcomes. Here, we summarize the available evidence on the role of adipose inflammation in triggering cardiovascular impairment in the context of diet induced CMS with an emphasis on the involvement of perivascular adipose tissue. As well, we propose some possible molecular pathways linking intermittent fasting to the ameliorative effect on adipose inflammation and cardiovascular dysfunction under such circumstances. We highlight a number of targets, whose function changes in perivascular adipose tissue inflammation and could be modified by intermittent fasting acting as a novel approach to ameliorate the inflammatory status.

The Effect of Two Dietary Protein Sources on Water Quality and the Aquatic Microbial Communities in Marron (Cherax cainii) Culture

Feeding freshwater crayfish species with different diets not only affects the water quality but also induces the abundance of various microbial communities in their digestive tracts. In this context, very limited research has been undertaken to understand the impacts of various protein incorporated aqua-diets on the characteristics of water and its microbial communities. In this study, we have critically analysed the water quality parameters including pH, dissolved oxygen, nitrate, nitrite, ammonia and phosphorus, as well as bacterial communities under marron (Cherax cainii) aquaculture, fed fishmeal (FM) and poultry by-product meal (PBM)-based diets for 60days. The results unveiled that over the time, feeding has significant impacts on organic waste accumulation, especially ammonia, nitrate, nitrite and phosphate, while no effects were observed on pH and dissolved oxygen. Analysis of 16S rRNA sequence data of water sample indicated significant (P < 0.05) shift of microbial abundance in post-fed FM and PBM water with the evidence of microbial transmission from the gut of marron. Post-fed marron resulted in a significant correlation of Hafnia, Enterobacter, Candidatus Bacilloplasma and Aquitella with the quality and microbial population of water. The results of this study generated valuable knowledge database of microbes-water relationship for better health management practices and production of marron aquaculture fed with FM and PBM diets in under restricted feeding regime with the feeding ratios provided.

Observation on the growth of hubbard parent stock broilers raised for 20 weeks by manipulating the feed supply under restricted feeding regime

A study was carried out to monitor the effect of feed manipulation on the growth and development of male and female line Hubbard broiler parent stock reared under tropical open sided poultry house without any form of cooling system or any temperature regulating mechanism. A total of 255 females and 105 males for the male line and 360 females and 150 males for the female line were used. The birds were fed a normal soya cake/groundnut cake and maize based broiler starter ration of 2900kcal/kg ME and 20% CP and a grower ration containing 2650kcal/kg ME with 16% CP as stipulated by the Hubbard rearing guide. The birds were fed ad libitum for the first 2 weeks and thereafter placed on restricted feeding in line with the standard rearing guideline provided by the Hubbard breeding company for optimum growth and development. It was observed that the body weights of the birds did not differ much from the standard body weight expected at 20 weeks even though they were reared in the normal tropical open sided poultry house without sophisticated modern facilities. This shows that feed manipulation can be used to achieve desired weight in broiler parent stock rearing

Challenging the Integrity of Rhythmic Maternal Signals Revealed Gene-Specific Responses in the Fetal Suprachiasmatic Nuclei.

During fetal stage, maternal circadian system sets the phase of the developing clock in the suprachiasmatic nuclei (SCN) via complex pathways. We addressed the issue of how impaired maternal signaling due to a disturbed environmental light/dark (LD) cycle affects the fetal SCN. We exposed pregnant Wistar rats to two different challenges – a 6-h phase shift in the LD cycle on gestational day 14, or exposure to constant light (LL) throughout pregnancy – and detected the impact on gene expression profiles in 19-day-old fetuses. The LD phase shift, which changed the maternal SCN into a transient state, caused robust downregulation of expression profiles of clock genes (Per1, Per2, and Nr1d1), clock-controlled (Dbp) genes, as well as genes involved in sensing various signals, such as c-fos and Nr3c1. Removal of the rhythmic maternal signals via exposure of pregnant rats to LL abolished the rhythms in expression of c-fos and Nr3c1 in the fetal SCN. We identified c-fos as the gene primarily responsible for sensing rhythmic maternal signals because its expression profile tracked the shifted or arrhythmic maternal SCN clock. Pathways related to the maternal rhythmic behavioral state were likely not involved in driving the c-fos expression rhythm. Instead, introduction of a behavioral rhythm to LL-exposed mothers via restricted feeding regime strengthened rhythm in Vip expression in the fetal SCN. Our results revealed for the first time that the fetal SCN is highly sensitive in a gene-specific manner to various changes in maternal signaling due to disturbances of environmental cycles related to the modern lifestyle in humans.

Restricted feeding of laying chicken and its effect on quality and lipid profile of the eggs

This study was undertaken to investigate the quality and the lipid profile of table eggs obtained from laying chickens fed on restricted diets. The experimental design was the completely randomized design. Seven-two laying birds which were 74 weeks old were assigned to three treatments which were made up of three replicate each. They were subjected to the same management conditions. The treatments consisted of the control, T1 (ad libitum feeding), T2 (7 am-11 am, 4 hours feed restriction) and T3 (7 am – 3 pm, 8 hours feed restriction). On completion of the 10 weeks feeding trial, fifteen fresh eggs were collected per treatment (5 eggs per replicate) for analysis of the external (egg weight, egg width, egg length, shell weight and thickness, egg shape index), internal (albumen weight and height, yolk weight, yolk height and yolk diameter, yolk ratio, yolk: albumen ratio, yolk index and the haugh unit) and the lipid profile (total cholesterol, triglyceride, high-density lipoprotein, HDL and low-density lipoprotein, LDL). The result indicated that significant differences (P &lt; 0.05) existed in the egg weight, egg width, egg length and egg index and most of the internal characteristics and the lipid profile examined. The birds that were fed the restricted diets had the best egg weight, width, egg length and Haugh unit (HU). The eggs collected from the four-hours feed restriction (7 am – 11 am) had the best high density lipoprotein (HDL) and lowest low lipoprotein (LDL). It was concluded that farmers can confidently practice restricted feeding regime, especially for four hours (7 am – 11 am) when using commercial layers feed.

Effects of digestible protein and energy levels, and their ratio under restricted feeding regimes on growth and feed utilization of yearling greater amberjack (Seriola dumerili) at suboptimal temperatures

Effects of digestible protein and energy levels, and their ratio under restricted feeding regimes on growth and feed utilization of yearling greater amberjack (Seriola dumerili) at suboptimal temperatures

Effects of Strain and Skip-A-Day Feed Restriction on Haematological Parameters of Broiler Chickens at Finisher Stage

Feed restriction is a management tool designed to reduce the amount of feed consumed by birds to produce more meat without jeopardizing their health condition. The present study was therefore, undertaken to investigate the effects of strain and feed restriction on haematological parameters of broiler chickens. The strains of broilers reared are Arbor Acre, Hubbard and Marshall. The four treatments and three replicates per treatment applied are: A- full feeding (control), B-5th week feed restricted, C- 6th week feed restricted and D- 7th week feed restricted groups. After each feed restriction regime the birds were restored to full feeding until the termination of the experiment on the 56th day. At the end of the experiment on the 56th day, two birds from each replicate were randomly selected for blood collection. Analyzed results showed that there was no significant (p&gt;0.05) effect of strain on all the haematological parameters at 8th week except for red blood cell. With respect to red blood cell, Hubbard birds showed superiority to other two strains which recorded similar (p&gt;0.05) mean values. All feeding trials employed had positive impact on the birds’ hematological parameters regardless of strain. Therefore, any of the feed restriction regime could be employed without compromising the health of the birds.

Impacts of Feeding Restriction Regimes on Economic and Productive Performance of Nile Tilapia Fish

This study investigated the effect of feeding restriction regimes on economic and productive performance of Nile tilapia Oreochromis niloticus. Sixty Nile tilapia fish were randomly classified into three groups (n=10/group) with similar initial body weight. Group I (Control group) was fed three times daily for 32 days. Group II was deprived for 4 days and then re-fed for 16 days, while Group III was deprived for 8 days and then re-fed for 32 days. The experiment was terminated after 10 weeks. All groups were fed on commercial diet at 2% of body mass. Indicate parameters measured were weight gain, feed efficiency, feed conversion ratio, economic conversion ratio and water quality. The above parameters were measured every 2 weeks. The results revealed that, after 64 days, Fishes which exposed to long starvation periods (8F:32R) consumed significantly (P= .01) more feed compared to other the restricted group (4F:16R). The highest feed efficiency was observed in fish exposed to 4F:16R. However, this group showed less feed intake than the 8F:32R and control groups. Moreover, cost benefit analysis under restriction indicated that, the highest return observed in control group and restricted fish for 4 days and the lowest in restricted fish for 8 days (P= .05). On the other hand, parameters of water quality (pH, Dissolved oxygen, Turbidity and Ammonia) were significantly (P= .01) affected by feed restriction regimes. Turbidity and ammonia levels were more in control group than the restricted groups.