Increased Feeding Frequency Research Articles

Analysis of the impact of environmental enrichment on the behaviors of bioterium rats

Rats are often used in experimental research due to their intelligence and ease of handling. However, traditional housing conditions can limit their natural behaviors, potentially leading to discomfort. Environmental enrichment aims to increase behavioral diversity, promote healthy behaviors, encourage positive use of the environment, enhance the animal's ability to cope with stressors, and reduce stereotypic behaviors. This study primarily aimed to assess the impact of environmental enrichment on laboratory rat behaviors. A group of 18 rats was selected and divided into three groups (n=6): control, physical enrichment, and feeding enrichment. The enrichment groups were provided with specific objects (a plastic tube for physical enrichment and a seed-filled cardboard roll for feeding enrichment) over a 10-day period, with open field tests conducted on days 1, 5, and 10 to evaluate time spent in central and peripheral zones. Statistical analyses were conducted in RStudio using t-test (p<0.05) to compare open field activity, water intake, and food consumption across groups. Results showed that animals exposed to environmental enrichment displayed fewer stereotypic behaviors and increased feeding frequency. Thus, assessing the impact of physical and feeding enrichment in rats of laboratory demonstrates that enrichment strategies provide positive impacts on animal welfare.

Optimizing feeding frequencies in fish: A meta-analysis and machine learning approach

Feeding is a critical factor in aquaculture, directly impacting cultivation success and profitability. Feeding frequency determines feed intake and regulates fish appetite and nutrient utilization. However, the effects of increased feeding frequency on fish growth and feed conversion ratio (FCR) can vary depending on species, cultivation conditions, feeding rates. This variability can lead to inconsistencies in interpretations, with individual studies often lacking in statistical power. To address this issue, we analyzed data from 145 study cases across 53 publications to quantify the impact of feeding frequency on average daily weight gain (ADG) and FCR. Our meta-analysis revealed that increasing feeding frequency could reduce FCR, but it did not enhance ADG when daily feed amounts were fixed. Only when each feeding reached satiation did increased feeding frequency boost ADG. We found that the relationship between feeding frequency and ADG in fish is quadratic, with most fish species achieving optimal ADG at four feedings per day. Traditional approaches suggest that fish appetite recovery is linked to gastric evacuation time, defining an optimal feeding interval at 80 % gastric evacuation. However, our research indicates that this approach is not suitable for all fish species. Therefore, we developed a Gradient Boosting Machine (GBM) model that predicts FCR (R2 = 0.9303) and ADG (R2 = 0.7249) based on environmental variables, fish characteristics, culture period, and feeding frequency. This study provides a scientific basis for formulating more efficient and sustainable aquaculture feeding strategies, optimizing growth and feed utilization across different fish species.

Effect of Concentrate Feeding Frequency on Growth Performance of Sirohi Goat Kids

Background: The growth rate and body weight increased with increment in feed frequencies due to microbial activities enhancing nutrient absorption in the animal’s body (Yaunas et al., 2014, Bawala et al., 2009). The efficacy of growth by increased feeding frequency is due to a large improvement in the efficiency of food utilization. Smaller ruminants require more frequent feedings than larger ruminants because of their higher basal metabolism. Methods: The effects of concentrate feeding frequency on growth performance were assessed in a three-month trial including twenty-one female Sirohi goat kids. Three groups (T1, T2 and T3) containing concentrate were randomly assigned to feed the Sirohi goat kids once, twice, or three times a day. Throughout the ninety-day trial, uniform management techniques and feeding like green or dry fodder were kept up. Each animal was given an exact quantity of food and water each morning during the trial and the remaining feed and water were weighed the next morning. Result: Total daily feed intake was significantly (P less than 0.01) higher in T3 (885.88±4.06 g/d) than in T2 (775.03±7.52 g/d) and T1 (702.54±5.78 g/d). Average daily weight gain (ADG) was significantly (P less than 0.01) higher in T3 (43.68±1.8 g) than in T1 (32.30±2.61 g) and T2 (37.73±2.42 g). Non-significantly differing feed conversion ratio (3.06±0.31) in T3 than in T2 (3.16±0.29) and T1 (3.39±0.31), indicating a positive impact of thrice-a-day concentrate feeding on feed intake and growth but not affect feed efficiency in goat kids.

Impact of feed on the yield of Litopenaeus vannamei and Macrobrachium rosenbergii prawn culture from West Godavari district, Andhra Pradesh, India

Aquaculture, a vital sector addressing global food demand, is characterized by its extensive water requirements. Categorized into mariculture, freshwater aquaculture, and brackish water aquaculture, the sector plays a crucial role in food production. This study focuses on prawn cultivation, a significant aspect of aquaculture, emphasizing the influence of feed quality and hydrographic parameters on yield and ecological sustainability. Conducted in Vissakoderu village (Litopenaeus vannamei) and Eduru village (Macrobrachium rosenbergii), the research employed commercial feed, optimizing physicochemical parameters such as temperature, pH, and salinity. Probiotics were integrated into the feed to enhance prawn growth. Results indicated optimal levels of moisture, lipids, protein, fiber, carbohydrates, minerals, and vitamins in the feed. The progressive weight gain of prawns, reaching 30.00 kg for 1000 prawns, was correlated with an increased feeding frequency. Scientifically monitored hydrographic conditions and feed quality contributed to a remarkable average yield of 29 tons for Litopenaeus vannamei and 63.33 tons for Macrobrachium rosenbergii over three years. This underscores the importance of precision in aquaculture practices for both yield enhancement and ecological preservation. The study provides valuable insights into the sensitivity of prawn cultivation, emphasizing the need for meticulous care in managing hydrographical, feed, and disease parameters.

3. Increased feeding frequency pre-farrowing does not improve farrowing results of sows

3. Increased feeding frequency pre-farrowing does not improve farrowing results of sows

Feeding frequency on survival, growth, blood glucose of glass eel, Anguilla bicolor bicolor cultured in a recirculating aquaculture system

Indonesian shortfin eel, Anguilla bicolor bicolor is one of the eel species that high market demand both for local and export. Feeding frequency is an important that related to production for culture. The purpose of this experiment is to determine the optimal feeding frequencies on survival and growth of shortfin eel at glass eel to elver stages cultured in a recirculating aquaculture system. Four treatments of different feeding frequencies and three replicates each were performed. The treatments were as followed A) 1 time a day; B) 2 times a day; C) 3 times a day; and D) 4 times a day. The result showed that the feeding frequency affect the survival, length and weight growths, and glucose value. The best of survival rate (82.61±3.15%), weight (1.91±0.28 g) and length (10.64±0.45cm) found at feeding frequency 3 times a day compared to the others (P<.0.05). Blood glucose value increases with increasing feeding frequency. Water quality such as dissolved oxygen (DO), temperature and pH were within the optimal range. Three times a day of feeding frequency is recommended for applying on glass eel culture in a recirculating aquaculture system.

Measures of Adrenal and Gonadal Hormones in Relation to Biological and Management Factors among Captive Red Pandas in Indian Zoos.

Animals in human care are affected by stressors that can ultimately reduce fitness. When reproduction is affected, endangered species conservation programs can be severely compromised. Thus, understanding factors related to stress and reproduction, and related hormones, is important to ensure captive breeding success. Red pandas (Ailurus fulgens) are endangered, and populations in the wild are threatened with extinction. A global captive breeding program has been launched to conserve the species with the goal of reintroduction. However, there is little information on how stressors impact physiological aspects of the species. This study measured fecal glucocorticoid (fGCM), progestagen (fPM), and androgen (fAM) metabolite concentrations in 12 female and 8 male red pandas at 3 zoos in India to determine predictors of adrenal and gonadal steroid activity, and the influence of fGCM on reproduction. Based on the generalized linear mixed model (GLMM), fGCM concentrations were positively correlated with the number of visitors, number of nests and enclosure areas, and negatively related to frequency of feedings, log density, and social time, while fPM concentrations were negatively associated with enclosure areas. A confounder for enclosure areas and number of nests was the fact that these spaces were relatively barren, with limited hiding spaces, compared to the smaller enclosures. By contrast, no significant relationships were found for fAM, perhaps due to the smaller sample size. A negative relationship between fGCM and fPM was observed, indicating increasing adrenal hormones may decrease reproductive function among female red pandas. Results suggest that zoo management should consider increasing feeding frequency, providing larger enclosures with more enrichment and more nests in larger spaces, and regulating visitor numbers to support good welfare and potentially improve reproductive fitness of red pandas in captivity.

Transition cow nutrition and management strategies of dairy herds in the northeastern United States: Part III—Associations of management and dietary factors with analytes, health, milk yield, and reproduction

The objective was to evaluate relationships between putative periparturient management and dietary factors at the pen and herd levels with metabolic- and inflammation-related analytes, health disorders, milk yield, and reproductive performance. Multiparous and primiparous cows from 72 farms in the northeastern United States were enrolled in a prospective cohort study. Farms were visited 3 times during the prepartum and postpartum periods: during the far-off dry, close-up dry, and fresh periods. Pen measurements were taken at each visit for the pens where cows sampled were housed, and particle size was determined for the total mixed ration for the pen. A survey was used to acquire data on herd-level management variables. Blood samples were collected from the same 11 to 24 cows per farm during the close-up and fresh period visits. Whole blood was analyzed for postpartum β-hydroxybutyrate (BHB) concentrations, and plasma was analyzed for prepartum and postpartum nonesterified fatty acids (NEFA) and postpartum haptoglobin (Hp) concentrations. Health event, milk yield, and reproductive records were acquired through the records management software program used on the farm. For the pen-level analysis, primiparous and multiparous cows were analyzed separately. For the pen- and herd-level analysis, a simple linear regression was conducted on all possible explanatory variables. Variables were included in the full multivariable general linear model if P < 0.20, and a manual backward stepwise elimination process ensued until all variables had P < 0.10. Our results indicate that pen- and herd-level management factors are associated with blood biomarkers, health, milk yield, and reproductive performance. For the prepartum period, our results support increasing the proportion of particles on the 19-mm sieve of the Penn State Particle Separator, optimizing bunk space, and not overfeeding metabolizable energy (ME), to decrease the prevalence of elevated postpartum NEFA, BHB, and Hp concentrations, decrease disorder incidence, maximize milk yield, and improve pregnancy risk to first service. For the fresh period, our results generally support optimizing bunk space, avoiding commingling, increasing feeding frequency, avoiding high physically effective undigested neutral detergent fiber (NDF) after 240 h of in vitro fermentation and high total fermentable carbohydrate diets while optimizing the inclusion of forage NDF, and ensuring adequate diet ME and metabolizable protein to reduce the prevalence of elevated postpartum NEFA, BHB, and Hp concentrations, minimize disorder incidence, maximize milk yield, and improve pregnancy risk to first service. At the herd level, our results generally support not vaccinating in the calving pen, minimizing the number of prepartum and postpartum pen moves, and avoiding long stays in the calving pen after parturition to reduce the prevalence of elevated biomarker concentrations, decrease disorder incidence, increase milk yield, and improve reproductive performance.

Brood care behavior of the painted stork (Mycteria leucocephala) in Peninsular Malaysia

Abstract. Zakaria MA, Daud UNS, Mansor MS, Md. Nor S. 2022. Brood care behavior of the painted stork (Mycteria leucocephala) in Peninsular Malaysia. Biodiversitas 23: 5406-5411. Waterbirds can serve as bio-indicators for their surrounding environments, indicating issues such as habitat degradation and climate change. One factor that contributes to successful reproduction for many bird species is parental behavior during the brood care stage. The painted stork (Mycteria leucocephala) is a waterbird species that provide biparental care throughout the breeding season. Although many studies have focused on populations of this species, information about their behavior, particularly during nestling rearing, remains lacking. Hence, this study was conducted to examine the parental behavior of painted storks between the early and late stages of brood care in two different colonies located in Peninsular Malaysia: Tasik Shah Alam (TSA) in Selangor and Upper Bisa Putrajaya Wetland (UBPW) in Putrajaya from May to September 2016. Three pairs of painted storks were monitored in every site, and seven behaviors were identified: roosting, preening, nest repair, wing opening, flying, feeding and brooding. Of all the behaviors recorded, flying, roosting and wing-opening behavior were the most frequently observed behaviors in both study areas during the early stage of brood care. However, painted storks were found to spend most of their time flying when the chicks had grown up by the late stage. This may be due to the food demand for the parents and their chicks. As the nestlings grow bigger, more food is required before the nestling can fledge independently. This is supported by increased feeding frequency observed from the early to late stages. Males were found to have a higher frequency of all behaviors than females. This data facilitates a greater understanding of painted stork behavior, which can help in their conservation and management processes.

Brood care behavior of the painted stork (Mycteria leucocephala) in Peninsular Malaysia

Abstract. Zakaria MA, Daud UNS, Mansor MS, Md. Nor S. 2022. Brood care behavior of the painted stork (Mycteria leucocephala) in Peninsular Malaysia. Biodiversitas 23: 5406-5411. Waterbirds can serve as bio-indicators for their surrounding environments, indicating issues such as habitat degradation and climate change. One factor that contributes to successful reproduction for many bird species is parental behavior during the brood care stage. The painted stork (Mycteria leucocephala) is a waterbird species that provide biparental care throughout the breeding season. Although many studies have focused on populations of this species, information about their behavior, particularly during nestling rearing, remains lacking. Hence, this study was conducted to examine the parental behavior of painted storks between the early and late stages of brood care in two different colonies located in Peninsular Malaysia: Tasik Shah Alam (TSA) in Selangor and Upper Bisa Putrajaya Wetland (UBPW) in Putrajaya from May to September 2016. Three pairs of painted storks were monitored in every site, and seven behaviors were identified: roosting, preening, nest repair, wing opening, flying, feeding and brooding. Of all the behaviors recorded, flying, roosting and wing-opening behavior were the most frequently observed behaviors in both study areas during the early stage of brood care. However, painted storks were found to spend most of their time flying when the chicks had grown up by the late stage. This may be due to the food demand for the parents and their chicks. As the nestlings grow bigger, more food is required before the nestling can fledge independently. This is supported by increased feeding frequency observed from the early to late stages. Males were found to have a higher frequency of all behaviors than females. This data facilitates a greater understanding of painted stork behavior, which can help in their conservation and management processes.

Feeding frequency has a determinant role in growth performance, skeletal deformities, and body composition in the Mexican pike silverside (Chirostoma estor), an agastric short-intestine fish (Teleostei: Atheriniformes)

Several fish species with potential for aquaculture diversification possess agastric short-intestine anatomical configuration. The absence of a stomach or long intestine in fish may imply specific feeding frequency strategies for optimal growth. Because adequate feeding frequencies are paramount for thriving fish culture, the present study aimed to evaluate the effects of feeding frequency on growth performance, feeding efficiency, survival, deformities, proximate body composition, and muscle growth in Mexican pike silverside (Chirostoma estor: Atherinopsidae) a short-intestine agastric fish. Fish with an average weight of 180.57 ± 3.02 mg were randomly distributed in twelve tanks and fed four (M4), eight (M8), and twelve (M12) times a day until apparent satiety for 45 days. Significantly higher growth (70%) was found in M12 treatment compared to M4. There was no difference in survival among treatments. However, significantly fewer deformities were found in the M12 treatment compared to M8 and M4 treatments. Increased feeding frequency produced fish with higher lipids, with a concomitant reduction in ash content. Muscle fiber diameters were significantly different in all treatments: M12 (32.97 ± 3.13 μm), M8 (30.28 ± 4.59 μm), and M4 (26.74 ± 4. 42 μm). These results reflect the importance of feeding strategies in accordance to fish habits and their digestive configurations and may be relevant for other emerging species with similar digestive morphology and lower in the trophic chain, which are essential for aquaculture diversification and sustainability.

Effect of winter feeding frequency on growth performance, biochemical blood parameters, oxidative stress, and appetite-related genes in Takifugu rubripes.

Tiger pufferfish (Takifugu rubripes) is one of Asia's most economically valuable aquaculture species. However, winter production of this species in North China is limited by low water temperature and unavailability of high-quality feed, resulting in high mortality and low profitability. Therefore, the aim of this study was to evaluate the effect of feeding frequency (F1: one daily meal; F2: two daily meals; F3: four daily meals; F4: continuous diurnal feeding using a belt feeder) on the growth performance, plasma biochemistry, digestive and antioxidant enzyme activities, and expression of appetite-related genes in T. rubripes (initial weight: 266.80 ± 12.32g) cultured during winter (18.0 ± 1.0°C) for 60days. The results showed that fish in the F3 group had the highest final weight, weight gain rate, specific growth rate, survival rate, and best feed conversion ratio. Additionally, daily feed intake increased significantly with increasing feeding frequency. The protein efficiency and lipid efficiency ratios of fish in the F3 group were significantly higher than those of fish in the other groups. Furthermore, total cholesterol, triglycerides, and glucose levels increased with increasing feeding frequency, peaking in the F2 group and decreasing under higher feeding frequencies. The antioxidant (superoxide dismutase, catalase, glutathione, and glutathione peroxidase) and digestive (trypsin, amylase, and lipase) enzyme activities of fish in the F1 group were significantly higher than those of fish in the F3 and F4 groups. Additionally, there was a decrease in orexin expression with increasing feeding frequency. In contrast, the expression levels of tachykinin, cholecystokinin, and leptin increased with increasing feeding frequency, peaking in the F4 group. Overall, the findings of this study indicated that a feeding frequency of four meals per day was optimal for improved growth performance of pufferfish juveniles cultured during winter.

Supplementation of a dried, fungal fermentation product with fibrolytic enzymatic activity in the diet of dairy cows on feeding behavior, metabolic profile, milk yield, and milk composition

• Increased milk production from high-performance cows and decreased somatic cell count Supplementation with exogenous fibrolytic enzymes in the diet of ruminants can improve the use of nutrients by animals and, consequently, improve their productive performance. The aim of this study was to evaluate the effect of supplementing a dried fungal fermentation product with residual fibrolytic enzymatic activity (MAXFIBER®, Provita Supplements, Pinneberg, Germany) on digestibility, feeding behavior, productive performance, milk quality, and various metabolic parameters of high-producing dairy cows. Thirty-six multiparous Holstein dairy cows were divided into two groups: one group with supplementation of 10 g enzyme/cow/day (GS; n = 18), top-dressed on a total mixed ration, and a control group (CG; n = 18) without supplementation. The results were analyzed using a randomized block design over a 23-day experimental period. Milk yield was evaluated daily, and milk and blood samples were collected on days 0, 14, 19, and 23 to analyze the composition and quality of the milk and blood metabolites. DMI and eating behavior were assessed daily using electronic automatic feeders. Cows that received the enzyme-supplemented diet had higher milk production (p = 0.05), lower somatic cell count (SCC) in milk (p = 0.003), and reduced milk fat (p = 0.01). The assessment of feeding behavior showed a higher frequency of access to feeders and meals per day (p = 0.001) in cows that received enzymes in their diet. Blood glucose levels tended to increase in the group with supplementation of the enzyme product (p = 0.09). However, the treatment had no effect (p > 0.05) on DMI and diet digestibility. Fibrolytic enzymes are a useful tool in dairy cow nutrition, increasing milk yield and reducing SCC in milk. Moreover, the enzymes change feeding behavior by increasing feeding frequency.

Increased feeding frequency prior to farrowing: effects on sow performance.

Reducing the interval between the consumption of the last meal and the start of farrowing is suggested to increase the energy available to sows during farrowing, potentially reducing the farrowing duration and easing piglet births. The present study aimed to examine whether increasing feeding frequency from one to two feeds within standard production hours (0700 to 1500 hours) would produce a difference in farrowing duration and/or stillborn numbers. From entry to farrowing crates (110 ± 1 d gestation) to farrowing (116 ± 1 d gestation), multiparous sows (n = 118) were fed a daily fixed amount of feed either once at 0800 hours or in two meals at 0800 and 1300 hours. Sow weights and backfat depths were recorded on entry and exit from the farrowing crate. Litter size and weight were recorded 24 h after farrowing and on day 21 of lactation. Sows fed twice had a shorter farrowing duration and fewer stillborn piglets than those fed once (2.21 ± 0.56 h vs. 3.25 ± 0.52 h; P = 0.001). The interaction between treatment and farrowing duration showed that sows fed twice have a reduced farrowing duration and had significantly lower stillborn rates than those fed once or those fed twice with longer farrowing durations (P < 0.001). These findings suggest that increasing feeding frequency prior to farrow can reduce the farrowing duration and stillborn numbers in some sows, however, some sows remain with a high stillborn rate regardless of feeding frequency. Piglet average daily gain was greater in once-fed sows, but fewer of these sows remained in the herd at subsequent farrowing. Further, subsequent total born and born alive were higher in twice-fed sows. Feeding sows at a higher frequency can improve farrowing performance in some sows and could increase the longevity of the sow in the herd.

Abstract 105: A case of transient neonatal thyrotoxicosis

A 2 months old male infant born at 37 weeks of gestation to a mother with Grave's disease on therapy who had a failed radioactive iodine ablation in the past, presented to us with history of failure to gain weight, excessive cry and increased feeding frequency since 1st week of life. On examination he was irritable, weighed 3.5 kg (<5th centile, CDC charts) and had no goiter. The thyroid profile showed TSH <0.0025 IU/l, free T3 5.43 pg/ml, free T4 1.57 ng/dl and elevated TRAb levels (3.66 IU/l). The mother had high TRAb levels (40 IU/l) and the child was diagnosed with neonatal thyrotoxicosis, both the mother and the child were treated with carbimazole. The child received tapering dose of carbimazole during follow-up and achieved TRAb negative status by 8 months. The child is healthy currently and is off treatment.

Feeding frequency affects glucose and lipid metabolism through SIRT1/AMPK pathway in growing pigs with the same amount of daily feed

Eating patterns are associated with obesity and metabolic health. However, the regulating mechanism of different eating patterns on body metabolism are not fully cleare. In this study, a pig model was used to evaluate the effects of feeding frequency on glucose and lipid metabolism and reveal its regulating mechanism. Twenty-four growing barrows were randomly allocated to 1-meal (M1), 3-meal (M3), or 5-meal (M5) per day groups with the same amount of daily feed. GSEA was conducted on the liver to investigate the pathways of different feeding frequencies on the metabolism. The serum glucose, NEFA, VLDL-C levels were higher for M1 group than for M3 and M5 groups, however, the hepatic TRIG level was lower. Liver transcriptome showed that glycolysis/gluconeogenesis and fatty acid metabolism pathways were suppressed with the increase of feeding frequency. The increase of gluconeogenic substrates (glycerol and lactate) and enzymes (PEPCK1 and G6Pase) in liver indicated that hepatic gluconeogenesis was enhanced in the M1 group. AMPK/PPARα signaling associated genes were positively correlated with NEFA and β-HB levels in M1 group, which promoted fatty acid oxidation and ketogenesis in liver. Moreover, compared with M3 and M5 groups, the higher NAD+/NADH ratio in the liver of M1 group activated SIRT1, which stimulated the AMPK signaling associated pathways by up-regulating the LKB1 gene. These findings provide evidence for the regulating roles of feeding frequency on glucose and lipid metabolism through SIRT1/AMPK pathway, which greatly contributes to the regulation of energy metabolism through daily eating patterns in animals.

Effects of different feeding frequencies on the growth, plasma biochemical parameters, stress status, and gastric evacuation of juvenile tiger puffer fish (Takifugu rubripes)

Tiger puffer fish (Takifugu rubripes)is one of the most economically valuable aquaculture species in Asia. However, farming tiger puffer fish at the juvenile stage has been greatly restrained by cannibalization caused by inappropriate feeding regimes, resulting in very high mortality and great economic loss, particularly in intensive recirculating aquaculture systems. Therefore, the feeding strategy should adapt to fish appetite, nutrition requirements and welfare in intensive aquaculture. A 60-day feeding experiment was conducted to evaluate the effects of feeding frequency on the overall health of juvenile tiger puffer fish. Fish were randomly assigned to four groups with different feeding frequencies using the same ration size per feeding. P1: two daily meals; P2: four daily meals; P3: six daily meals; P4: continuous diurnal feeding using a belt feeder. Fish in the P2 group exhibited optimal values for growth, including final weight, weight gain rate, specific growth rate, feed efficiency, and survival (P < 0.05), followed by those in the P3 group. The crude lipid content increased significantly with increasing feeding frequency (P < 0.05), indicating that high frequency feeding could accumulate higher body fat content. The apparent digestibility coefficients of dry matter, protein, and lipid were significantly lower for fish in the P4 group than for those in the other groups (P < 0.05). The total cholesterol, triglyceride, and glucose levels increased significantly with increasing feeding frequency (P < 0.05), indicating that high frequency feeding leads to excessive accumulation of dietary carbohydrates and lipids in juvenile tiger puffer fish. Fish in the P1 and P4 groups exhibited relatively higher antioxidant enzyme activities (P < 0.05), which suggested that low and high feeding frequencies cause oxidative stress in juvenile tiger puffer fish. A comparison of non-linear model parameters revealed that an exponential model best described the gastric evacuation rate of juvenile tiger puffer fish, with approximately half the meal passed within 3 h, which further confirmed that feeding intervals in four times/day may more closely align with the digestive physiological characteristics of juvenile tiger puffer fish. Overall, these results indicate that the best growth performance and physiological indicators can be achieved when fed at 4 times/day.

Feeding Frequency Modulates the Intestinal Transcriptome Without Affecting the Gut Microbiota in Pigs With the Same Daily Feed Intake.

The objective of this study was to elucidate the impacts of irregular eating patterns on gut microbiota and transcriptomic responses in a pig model with different feeding regimens. The experiment involved 24 growing pigs (Duroc × Landrace × Large White, 48 days of age) which were randomly allocated to one of three feeding patterns: one-meal (M1), three-meals (M3), or five-meals (M5) per day with the same daily feed intake. The results showed that different feeding frequencies had no significant effects on the microbial composition of ileal digesta, colonic digesta, colon mucosa, as well as the concentration of SCFAs in colonic digesta. Mucosa transcriptomic profiling data showed the pathways related to vitamin metabolism were enriched in the ileum and colon of pigs in the pairwise comparison between M3 and M1 groups. On the other hand, the pathways related to lipid metabolism were enriched in the ileum and colon of pigs in the pairwise comparison between M5 and M1 groups. Lastly, the pathways related to protein metabolism were enriched in the colon in the pairwise comparison between M3 and M1 groups, M5 and M1 groups, M5 and M3 groups, while the ileum was not enriched. Differentially expressed genes (DEG) related to metabolism showed that carbohydrate transport was suppressed in the ileum and enhanced in the colon in M5 and M3 groups compared with the M1 group. Compared with the M3 group, carbohydrate transport in the ileum was enhanced in the M5 group, while in the colon was inhibited. With the increase of feeding frequency, the catabolism, biosynthesis, and transport of lipid in the ileum were suppressed, while those in the colon were enhanced. Compared with the M1 group, amino acid transport in the ileum and colon in the M3 group was enhanced. Amino acid catabolism in the ileum in the M5 group was enhanced compared with M1 and M3 groups. In summary, different feeding frequencies affected the transport of carbohydrate, lipid, and amino acid in the ileum and colon, and affected the catabolism and biosynthesis of lipid in the ileum and colon with a low impact on intestinal microbiota.

The optimal feeding frequency for largemouth bass (Micropterus salmoides) reared in pond and in-pond-raceway

Largemouth bass is a carnivorous fish commercially important for freshwater aquaculture worldwide, however, the optimal feeding regime for the fish reared in pond has not been established. The present study examined feed intake, growth, feed utilization, body composition and waste outputs of largemouth bass fed at different feeding frequencies in pond and in-pond-raceway (IPR). Two 10-week feeding trials (I and II) were conducted simultaneously. Fish were fed at 1, 2, 3 or 4 meal d−1 in pond (trial I), and were fed at 2 or 3 meal d−1 in either pond or IPR (trial II). The initial body weight was 43.0 ± 0.2 g fish−1. In trial I, weight gain increased with increasing feeding frequency from 1 to 3 meal d−1, but no significant difference was found in weight gain between fish fed at 2, 3 and 4 meal d−1. The lowest retention efficiencies of nitrogen (NRE) and phosphorus (PRE) and the highest feed intake and phosphorus waste occurred in fish fed at 4 meal d−1. In trial II, no significant difference was found in weight gain between fish fed at 2 and 3 meal d−1 in IPR, while NRE, PRE and energy retention efficiency (ERE) were lower in fish fed at 3 meal·d−1 than in fish fed at 2 meal d−1. Weight gain, NRE, PRE and ERE were lower, while feed intake, body lipid content, wastes of nitrogen, phosphorus and carbon were higher, in fish reared in IPR than in fish fed at the same feeding frequency in pond. The present study indicates the optimal feeding frequency was 3 meal d−1 for largemouth bass reared in pond, and 2 meal d−1 for the fish reared in IPR. According to production performance, the IPR should not be an appropriate grow-out system for commercial largemouth bass farming.

Effects of feeding frequency on growth performance, feed intake, metabolism and expression of fgf21 in grass carp (Ctenopharyngodon idellus)

Grass carp (Ctenopharyngodon idellus) is one of the most important freshwater cultural species in China. However, obesity, fatty liver and digestive tract inflammation commonly exist in commercial grass carp, which may be due to excessive food and energy intake in daily feeding. Therefore, the feeding strategy should adapt to fish appetite, nutrition requirements and welfare in intensive aquaculture. To investigate the effects of feeding frequency on growth, physiology and metabolism-related fgf21 expression to provide a reference for the selection of feeding strategy, healthy and homogeneous juvenile grass carp (45.2 ± 2.5 g) were randomly divided and adapted to four feeding frequencies of 1, 2, 3 or 4 times/day following satiated feeding for 8 weeks. The growth rate increased with increasing feeding frequency. The hepatosomatic and abdominal fat-somatic indexes were higher in the higher feeding frequency groups, while the gut-somatic index was higher in the low feeding frequency groups (P < 0.05). The actual feeding ration increased from 1.3% to 3.5% with increasing feeding frequency (P < 0.05), and the feed conservation ratio increased from 1.5 to 2.3, but there was no significant difference between 3 and 4 meals/day (P˃0.05). The levels of serum glucose, triglycerides and total cholesterol also increased with increasing feeding frequency, while glycogen levels were higher in the 1 time/day group in both liver and muscle. The activities of digestive enzymes were higher in the high feeding frequency groups. Fgf21 gene expression was relatively low in the low feeding frequency group in all tissues, and the expression levels increased with increasing feeding frequency in the liver and muscle. Overall, the optimal feeding frequency to enhance the growth and health of juvenile grass carp is 3 times/day under apparent satiation.