Dietary Protein Level Research Articles

Nutritional Profile and Chlorophyll Intake of Collard Green as a Convenience Food

Background/Objectives: Collard green (Brassica oleracea var. viridis) is widely cultivated for its adaptability and nutritional benefits. This study examines the nutritional composition and chlorophyll content of the “Couve-Manteiga” cultivar grown in Italy, emphasizing its potential application in convenience foods, such as fresh-cut, fifth-range, and freeze-dried products, to enhance chlorophyll intake in the population. Methods: The leaves of collard greens were analyzed for proximate composition, mineral content, amino acid and fatty acid profiles, and chlorophyll levels. Chlorophyll retention was measured after sous vide cooking and freeze-drying to assess the efficacy of these preservation methods. The chlorophyll content of different product formats was quantified, and potential dietary contributions were estimated based on consumption data. Results: Collard greens exhibited a low caloric value (30.66 kcal/100 g), with high levels of dietary fiber (3.39 g/100 g), protein (3.01 g/100 g), calcium (333.09 mg/100 g), and potassium (215.53 mg/100 g). The amino acid profile revealed an essential to non-essential amino acid ratio of 0.72. Chlorophyll retention was notably high in both freeze-dried (97.66%) and sous-vide cooked products (83.5%), indicating the effectiveness of these methods in preserving chlorophyll content compared to fresh-cut leaves. Conclusions: The results suggest that convenience foods made from collard green leaves provide an accessible means to boost chlorophyll intake and enhance daily nutrition, offering a practical solution for increasing the consumption of this nutrient-rich vegetable.

Impact of dietary protein and lipid levels and growth rates on the intestinal microbiota of kuruma shrimp (Penaeus japonicus)

Impact of dietary protein and lipid levels and growth rates on the intestinal microbiota of kuruma shrimp (Penaeus japonicus)

Effects of dietary lipid and protein levels on growth, body composition, antioxidant capacity, and flesh quality of mandarin fish (Siniperca chuatsi)

Effects of dietary lipid and protein levels on growth, body composition, antioxidant capacity, and flesh quality of mandarin fish (Siniperca chuatsi)

Technological processing of Phaseolus vulgaris and Morus alba leaves to create a new nutritional food product for individuals with diabetes

Nutritionists found beans still rarely consumed in Western diet, despite its high nutritional value was proven and recommended by authorities. The study aimed to propose a simple and effective way of manufacturing a new common bean-based product targeted to diabetics. The key components, including important protein (common beans) and antidiabetic (white mulberry) sources, were carefully selected due to their proven properties. The formulated product underwent extensive analysis: composition, sensory and structure attributes, antioxidant and anti-enzymatic activity showing its antidiabetic potential. Additionally, the proposed label information was presented. The results demonstrate that the proposed blend of ingredients yields a product of exceptional nutritional value, with significant levels of both soluble and insoluble dietary fibers (36.66–48.49%) and proteins (21.22–18.25%). Furthermore, the product exhibits notable antiradical and anti-enzymatic properties. Through precise control of ingredient proportions, conventional raw materials can be fortified with a diverse array of plant-based sources renowned for their health benefits, while maintaining a palatable taste for consumers. The designed product, a savory snack with added bioactive compounds, represents an interesting option for consumers, holding promise as a potential dietary option with low glycemic index (40) for diabetics (anti-glucosidase activity ranged 66.72–70.66%). This study emphasizes the potential of plant-protein-rich foods in offering health-promoting benefits and further supports the use of common beans and natural antidiabetic agents in developing innovative food products.

Effects of Dietary Protein and Lipid Levels on the Growth Performance and Serum Biochemical Indices of Juvenile Furong Crucian Carp

The impact of dietary protein and lipid levels on the growth performance, feed utilization, and serum biochemical indices of Furong crucian carp was examined. Five hundred and forty carp (2.35 ± 0.08 g) were randomly assigned to nine groups and fed diets with three different protein levels (30.0, 35.0, and 40.0%) and three different lipid levels (4.0, 7.0, and 10.0%) for 60 days. The current findings revealed that the interaction effect between dietary lipid and protein levels exhibited significance for the final average weight (FAW), weight gain rate (WGR), specific growth rate (SGR), feed efficiency (FE), energy deposition rate (EDR), whole-fish energy, ash, and fat content (p < 0.05). Specifically, there was a significant reduction in FAW, WGR, and SGR with increasing dietary fat supplementation. Conversely, FE, EDR, and protein efficiency ratios were significantly decreased with increasing dietary protein levels (p < 0.05). Furthermore, serum albumin and globulin levels exhibited significant increases in response to dietary lipid inclusion (p < 0.05). The findings collectively indicate that Furong crucian carp fed a diet comprising 4% lipid and 30% protein exhibited the optimal growth and feed utilization. Conversely, excessive protein and lipid supplementation were detrimental to growth and resulted in the aggravation of metabolic disorders.

Effect of varied levels of dietary protein and lipid on growth response, nutrient utilization, and whole body composition of climbing perch, Anabas testudineus (Bloch, 1792) fry

Effect of varied levels of dietary protein and lipid on growth response, nutrient utilization, and whole body composition of climbing perch, Anabas testudineus (Bloch, 1792) fry

Effects of Different Protein and Lipid Levels in Practical Diets for Yellowtail Snapper, Ocyurus chrysurus (Bloch, 1971)

Effects of Different Protein and Lipid Levels in Practical Diets for Yellowtail Snapper, Ocyurus chrysurus (Bloch, 1971)

Low protein diet influences mineral absorption and utilization in medium-growing yellow-feathered broilers from 1 to 30 days of age

Reduced-protein diet can save protein ingredients and reduce nitrogen (N) losses. However, the effect of low protein diet on the mineral uptake and utilization in broilers needs to be explored. The aim of this study was to investigate the effect of low-protein diet on the growth performance, N deposition, mineral contents in serum, tissues and excreta, and the activities and gene expression of related enzymes in tissues of medium-growing yellow-feathered broilers, so as to elucidate the relationship between dietary protein level and the absorption and utilization of minerals in broilers. A total of 72 1-d-old Spotted-Brown male broilers were randomly allotted to 1 of 2 treatments with 6 replicate cages of 6 birds per cage for each treatment. The dietary crude protein (CP) levels for the two treatments were 21 % (the control treatment) and 19 % (low protein treatment), respectively. The experimental period was 30 d. The results showed that no differences (P > 0.05) were detected in average daily gain, average daily feed intake and feed: gain ratio of broilers during 1 to 30 d between the two treatments. However, low protein intake increased (P < 0.05) N retention rate, serum P, Cu and Mn, and excreta Cu, Mn and Zn, and decreased (P < 0.05) liver P and excreta P. In addition, birds fed low protein diet had higher (P < 0.05) manganese superoxide dismutase, and total superoxide dismutase activities in liver, and total antioxidant capacity and malondialdehyde content in heart, and lower (P < 0.05) copper-zinc superoxide dismutase (CuZnSOD) and succinate dehydrogenase activities in liver and CuZnSOD mRNA level in heart. In conclusion, the reduction of dietary CP content from 21 % to 19 % improved N retention, the absorption of P, Cu and Mn, as well as the antioxidant ability of liver and heart, and influenced metabolic utilization of P, Cu, Zn, Fe and Mn in medium-growing yellow-feathered broilers from 1 to 30 d of age.

Effects of dietary protein levels with cottonseed protein concentrate inclusion on growth, feed utilization, liver health and intestinal microbiota of juvenile largemouth bass (Micropterus salmoides)

An 8-weeks growth trial was conducted to evaluate the effects of dietary protein levels mainly based on cottonseed protein concentrate (CPC) meal on growth performance, protein metabolism, liver health and intestinal microbiota of largemouth bass (Micropterus salmoides) juveniles. Five isolipidic (100 g/kg) diets were prepared with protein levels ranging from 400 to 560 g/kg, with CPC of 155 g/kg, 214 g/kg, 272 g/kg, 330 g/kg, 390 g/kg to obtain five experimental diets with gradient protein levels (399.9 g/kg, 428.0 g/kg, 462.8 g/kg, 503.5 g/kg and 541.5 g/kg, respectively (CPC1, CPC2, CPC3, CPC4 and CPC5)). 300 fish (initial body weight: 14.71 ± 0.50 g) were randomly assigned into 15 tanks (3 tanks per diet). The results showed that, the fish of CPC5 group had the highest specific growth rate (SGR), weight gain (WG) and feed efficiency (FE) (P < 0.05). Increased dietary protein up-regulated most liver key genes of mTOR pathway (akt, tor, s6k, 4ebp1, s6) while down-regulated atf4 at medium dietary protein (P < 0.05). The expression of fas was down-regulated with increased dietary protein, while dgat1 was higher at CPC5 group (P < 0.05). The genes related to lipolysis were up-regulated with increased dietary protein (P < 0.05). The key genes of apoptosis including bcl2, casp9, casp3 (apoptosis) oxidative stress and endoplasmic reticulum stress were significantly up-regulated at high dietary protein (P < 0.05), which reduced the antioxidant and anti-stress capacity of the liver. Dietary 462.8 g/kg protein could maintain the normal composition and metabolic function of intestinal microbiota. In summary, dietary protein requirement using CPC as main protein source was estimated to be 463 g/kg to 510 g/kg for liver health or best growth of largemouth bass juveniles.

Environmental benefits of crude protein reduction in growing pig diets: is it worth going further?

Nitrogen (N) excretion and emissions can be reduced in fattening pigs by reducing dietary crude protein (CP) levels. Effects of this strategy are well documented for moderate CP reduction, but little literature exists on further CP reduction made possible by free isoleucine, histidine, and leucine. This trial evaluated the effects of 2 levels of reduction in CP on growth performance, N balance, and gaseous emissions. Forty-eight pigs were allocated to 12 gaseous emission-measuring chambers at 28kg live weight. Three dietary treatments (CTRL; -1.2pt; -2.4pt), with a CP content, respectively, of 18.1%, 16.9%, and 15.0% in phase 1 (28 to 48kg) and 16.1%, 15.0%, and 13.8% in phase 2 (48 to 80kg), were fed ad libitum. Growth performance was recorded for each phase. Body lipid and protein composition were analyzed by dual-energy X-ray absorptiometry in 2 animals per chamber at the beginning and end of the trial. These results were used to calculate the N balance. Slurry volume and composition were measured at the end of the trial. Ammonia, methane, and nitrous oxide emissions were recorded continuously. Data were analyzed with a general linear model including the linear and quadratic effect of CP reduction and phase as fixed effects. A trend for a quadratic effect of CP reduction on feed intake was observed (P = 0.085) with a decrease from CTRL to -1.2pt and then an increase with the -2.4pt treatment. Daily gain and gain to feed were improved by the low CP diets in phase 1 but were degraded in phase 2 (phase × CP interaction, P < 0.001) while body composition was not affected. Nitrogen excretion decreased with CP reduction (linear effect, P = 0.023) but tended to plateau with the low CP diets (quadratic effect, P = 0.081). Methane emissions per kg of gain were reduced with CP reduction (linear effect, P = 0.031). Ammonia emissions decreased with CP reduction, mostly in phase 1 (phase × CP interaction, P = 0.015); however, the emission factor (g N-NH3 / g urinary N) was not affected. Nitrous oxide emissions were not affected by CP reduction and its emission factor (g N-N2O / g N) tended to increase (linear effect, P = 0.07). Slurry ammonia-N decreased (linear effect, P < 0.023; quadratic effect, P = 0.049), but other slurry components were not significantly impacted. In this trial, a plateau in N excretion and emission reduction was reached with the -2.4pt treatment. Nevertheless, it is important to study such a reduction in conditions closer to commercial ones.

Investigating effects of dietary protein manipulation and Ulva lactuca supplementation on the postprandial metabolism and nitrogen excretion of Australian hybrid abalone

Abalone diets continue to be refined to suit the physiological and macronutrient requirements of different aged abalone under various seasonal conditions, primarily through dietary protein manipulation. Recently, dietary macro-algae supplementation has gained interest as an promoter of health and growth in abalone. In this study, the effects of three graded levels of dietary protein (35, 41 and 47 %) and 15 % dietary supplementation of dried and ground Ulva lactuca on the digestion and excretion processes in juvenile Australian hybrid abalone (Haliotis rubra x H. laevigata) were investigated through analysis of metabolic oxygen consumption (ṀO2) and nitrogen excretion (ṀNH4+−N) during meal digestion and assimilation. Trials were conducted at three farm-relevant acclimation temperatures (12, 17 and 22 °C), and abalone acclimated to the highest temperature were additionally subjected to a simulated heatwave. Within the ranges of 35 and 47 % dietary crude protein, no differences were observed in total postprandial energy use, however, significant differences were observed between the three temperatures. Similarly, differences in nitrogen excretion were observed across temperatures but not across dietary protein treatments. Dietary supplementation of U. lactuca led to significantly higher peak and total ṀO2 throughout the postprandial period at 22 °C. Additionally, total NH4+−N excretion was higher at 17 °C when abalone were fed the U. lactuca supplemented diet. No differences in survival were observed between any of the dietary treatments when juvenile abalone underwent the simulated heatwave, however, the 15 % U. lactuca treatment did exhibit consistently higher ṀO2. This information is useful for abalone farmers and feed formulators in developing season-specific diet formulations, particularly regarding macro-algae supplementation.

Effects of high-protein feeds on growth, free amino acid metabolism and protein metabolism-related genes in larvae and juveniles of rice flower carp (Procypris merus)

The effect of dietary protein on fish is widely studied. However, the high-protein diet effects and mechanisms on growth and amino acid metabolism in Procypris merus remain unclear. In this study, we investigated the effect of dietary protein levels (38 %, 44 %, 50 %) on the growth performance and amino acid contents in larvae and juveniles of P. merus. Transcriptome sequencing was used to study the adaptation mechanism of P. merus to a high-protein diet. The final length, specific growth rate, and protein efficiency ratio were remarkably decreased with increasing dietary protein levels, while the amino acid content of the body was significantly increased. In addition, 370,513,858 reads were obtained and assembled into 278,939 unigenes, with an average length of 559 bp. KEGG analysis revealed that differentially expressed genes were mainly involved in protein digestion and absorption, carbohydrate digestion and absorption, starch and sucrose metabolism, and pancreatic secretion. Moreover, high-protein increased the expression of genes involved in trypsin (prss, ctrl, cpa, cpb), peptide transporter (pept), amino acid transporter (b0at1), and gluconeogenesis (g6pase), which could digest and absorb the dietary protein, and converse amino acids into energy, resulting in adaption to a high-protein diet.

Full-length 16S rRNA gene amplicon analysis of gut microbiota in pigs fed with different diets in growing and finishing stages

The present study utilized full-length 16S rRNA gene sequencing to investigate the impact of dietary protein content on the composition and function of gut microbiota, and to analyze the gut microbiota of pigs in the growing (30 kg) and finishing (120 kg) stages under different feeding conditions. The results indicated that the gut microbiota was significantly different between pigs fed high- and low-protein diets. Comparing fecal samples from pigs at 30 and 120 kg, pigs at 30 kg showed a significant increase in the relative abundance of Clostridium butyricum, whereas at 120 kg, the abundance of Lactobacillus reuteri and Lactobacillus johnsonii decreased. To access the functional profiles and metabolic pathways based on amplicon sequence variants (ASVs), the microbiome of the 120 kg exhibited significant enrichments in Kyoto Encyclopedia of Genes and Genomes (KEGG) pathways related to metabolism-related category, including Alanine, aspartate and glutamate metabolism, Tyrosine and Thiamin metabolism, and Inositol phosphate metabolism. Meanwhile, analysis using the MetaCyc database showed that the metabolic pathways of the 30 kg group were significantly distinct when compared to the 120 kg of fecal samples. Overall, the findings indicated that the gut microbiota composition and function in the 30 and 120 kg fecal samples were markedly shaped by different dietary protein levels.

Effect of Dietary Digestible Protein Levels on Muscle Growth and Oxidative Stress in Amazonian Pintado (Pseudoplatystoma reticulatum × Leiarius marmoratus).

This study aimed to evaluate the effects of dietary digestible protein levels on the growth dynamics and oxidative stress status of white muscle fibers in Amazonian Pintado (Pseudoplatystoma reticulatum × Leiarius marmoratus). Four hundred and fifty-five juveniles of Amazonian Pintado were fed diets containing varying digestible protein levels (225, 250, 275, 300, 325, 350, or 375 g kg-1) for 75 days. At the end of the experiment, the fish were fasted for 24 h, anesthetized, and euthanized to obtain muscle samples. The linear and quadratic effects of dietary digestible protein levels on white muscle fiber diameter, metabolite concentrations, and oxidative stress were assessed. The results revealed that increasing dietary digestible protein levels linearly raised the concentrations of free amino acids and total proteins in muscle tissue but also led to elevated levels of TBARS, indicating increased oxidative stress. Notably, the average area of muscle fibers with a cell area greater than 1133 µm2 decreased, reflecting restricted muscle hypertrophy, whereas glycogen and glucose levels also declined. These findings suggest that although high dietary digestible protein enhances protein and free amino acid concentrations in muscle tissue, it may compromise muscle hypertrophy and increase oxidative damage in Amazonian Pintado, underscoring the complexity of optimizing diet formulation.

Effects of different forms of amino acid supplementation on the performance and intestinal barrier function of laying hens fed a low-protein diet

The aim of this study was to investigate the effects of low-protein diets and the sustained release of synthetic amino acids (AA) on the performance, intestinal barrier function and nitrogen excretion of laying hens. Two hundred eighty-eight 39-week-old Hyline brown laying hens of were randomly divided into 3 groups with 8 replicates per group. The crude protein level in the control group (CON) was 16%, the crude protein levels in the crystal AA supplement group (LCP-CAA) and microencapsulated AA group (LCP-MAA) were both 13%, and the AA levels in the LCP-CAA and LCP-MAA groups were consistent with that in the CON group. The experiment lasted 12 wk, and production performance was assessed weekly. The FCR and ADFI values were significantly greater for the LCP-CAA group than for the CON and LCP-MAA groups (P < 0.05). Two hours after feeding, His levels were significantly greater in the LCP-CAA group than in the LCP-MAA group (P < 0.05); 4 h after feeding, the contents of Met, Thr, Leu and Val were significantly greater in blood from the LCP-MAA group (P < 0.05); 6 h after feeding, Trp, Ile and Arg levels were significantly greater in the LCP-MAA group (P < 0.05). The chylase content significantly decreased in the duodenum of the LCP-CAA group (P < 0.05), and the chylase and trypsin were contents increased in the ileum of the LCP-MAA group (P < 0.05). In the LCP-MAA group, significantly increased mRNA expression levels of Occludin, ZO-1 in duodenum; Occludin, ZO-1, y+LAT1 in jejunum; and ZO-1 in ileum were detected at 8 and 12 weeks (P < 0.05). The fecal nitrogen content significantly decreased in the low protein diet group (P < 0.01). In conclusion, reducing dietary crude protein levels and supplementing with microencapsulated AAs can improve intestinal barrier function, promote digestive enzyme secretion, increase the expression of AA transporters, improve dietary protein utilization efficiency, and reduce nitrogen emission in laying hens.

Effect of different Energy and Protein levels in Hubbard broiler diet on Expression of some growth-related genes and Intestinal Morphology

Effect of different Energy and Protein levels in Hubbard broiler diet on Expression of some growth-related genes and Intestinal Morphology

Effect of different Energy and Protein levels in Hubbard broiler diet on growth performance and some related blood metabolic parameters

Effect of different Energy and Protein levels in Hubbard broiler diet on growth performance and some related blood metabolic parameters

Effects of dietary protein content on the productive and reproductive performance of unselected rabbit does and their litters during first two lactations

The aim of the present study was to evaluate the influence of different dietary protein levels on the productive performance of unselected rabbit does and their litters during their first two lactations. For this purpose, fifty-two nulliparous rabbit does, 4.5 months of age and live weight of 3115 ± 71 g, were divided into three groups (17 or 18 females per group), kept in individual cages and each group received only one of the three experimental diets. These diets were iso-energetic (10.8 MJ DE/kg), but with increasing levels of crude protein (CP): 15%, 17% and 19 % for the low (L), medium (M) or high (H) diets, respectively. Breeding was carried out by natural copulation using 6 males of 5-6 months of age and 2865±21 g initial weight, controlled semi-intensive lactation and weaning at 35 days after birth. Female body weight, feed intake, milk production, litter size and weight were monitored at birth and weekly after parturition during the first two lactations. The protein intake of the rabbits increased with the amount of protein in the diet (L vs. M: +12.2%; L vs. H: +18.8%; p &lt; 0.001), without any effect on milk production and feed intake. Milk production was unaffected by parity. Throughout the pre-weaning period, litter size and weight and maternal mortality were unaffected by dietary protein level. Dietary protein level had no effect on live weight, birth to weaning weight gain, milk production or feed intake during the first two consecutive lactations of rabbit does.

Growth and Laying Performance of Local Guinea Fowl on Different Dietary Protein and Energy Levels

Constraints to Guinea fowl (Numida meleagris) production include poor growth and low laying performance. However, the lack of standard nutritional requirements significantly hinders commercial indigenous Guinea fowl production in Nigeria. This study aimed to determine the proper levels of crude protein (14, 16, and 18%) and metabolizable energy (2.65, 2.75, and 2.85 Mcal/kg) in the diets of native Guinea fowl in Nigeria. The dietary protein (PL) and energy (EL) levels for the fowl were evaluated in a completely randomized 3 (PL) × 3 (EL) factorial design with three replicates of 10 birds each. Thus, 270 birds with 20 weeks of age were allocated randomly to nine dietary treatments (18P:2.65E, 18P:2.75E, 18P:2.85E, 16P:2.65E, 16P:2.75E, 16P:2.85E, 14P:2.65E, 14P:2.75E and 14P:2.85E). The PL × EL interaction affected Guinea fowl's DFI, DWG, and WWG (p&amp;lt;0.05), while WFI and FCR remained unaffected. The 16:2.85E diet increased the DFI of the birds compared to other diets (p˂0.05). The DFI of the 18:2.65, 18:2.75, and 16:2.75E Guinea fowls was higher than those of 18:2.85E, 14:2.65E, 14:2.75E, and 14:2.85 birds (p˂0.05). The DWG of fowls improved by the 16:2.85E diet compared to other diets, except for the 18P:2.65E and 16P:2.75E diets (p˂0.05). The interaction had a significant impact on the EN, EYH, and EM of the Guinea fowl egg while FCR remained unaffected. The 18P:2.85E diet improved the EN and EM of the birds compared to other diets (p˂0.05), The 18P:2.85E also improved the FCR for laying except for 14P:2.85E and 18P:2.75E. The 18P:2.85E diet influenced the YW of the birds compared to other diets (p˂0.05), whereas the EW of fowls improved by the 16:2.85E diet compared to other diets except for the 16P:2.65E diet (p˂0.05). In conclusion, feeding guinea fowls with a diet comprising 18% protein and 2.85 Mcal/kg metabolizable energy significantly improved egg production and quality.

Dietary inflammatory index, physical activity, body composition, and high sensitivity c-reactive protein levels in adolescent athletes in Central Java

Inflammation is the body's response to tissue damage and infection. Prolonged inflammation can increase the risk of non-communicable diseases, including cardiovascular disease. Some factors that can trigger inflammation are dietary patterns, high physical activity, and body composition. This study examined the correlation between dietary inflammatory index (DII), physical activity, body composition, and high sensitivity C-reactive protein (hs-CRP) levels. It examined differences in characteristics based on gender. This study was a cross-sectional design of 55 adolescent athletes at the Student Sports Education and Training Center in Central Java. The exclusion criteria were an athlete who had a physical injury (did not participate in training) and a smoker. The DII score was calculated based on the dietary pattern using SQFFQ, anthropometric data (weight, height, and nutritional status based on BMI/age), body composition (body fat percentage, fat mass, and fat-free mass) using the BIA tool, physical activity data for the last seven days using IPAQ and hs-CRP levels using the FIA method. Our result showed that the DII score was significantly correlated with hs-CRP (p=0.013). There was no correlation between physical activity, body composition, and anthropometry with hs-CRP levels (p0.05). There were differences in body height, body weight, body fat percentage, and fat-free mass between males and females (p0.001). The diet of athletes had anti-inflammatory potential (83.6%), as evidenced by the intake of vitamins and minerals, and athletes had low hs-CRP levels 1 mg/L (85.5%), indicating that no inflammation occurred. Future longitudinal research is needed with a large population of adolescent athletes to explain the role of anti-inflammatory and pro-inflammatory diets on the incidence of inflammation and measure physical exercise in athletes to reduce inflammatory bias.