Feeding Trial Research Articles

Effects of mulberry leaf powder water extract supplementation on the growth performance, immunity, antioxidant, meat quality and intestinal microbiota of yellow feather broilers.

A 50-day feeding trial was conducted to evaluate the effects of mulberry leaf powder water extract (MLE) on the growth performance, immunity, antioxidant, meat quality and intestinal microbiota of yellow feather broilers. A total of 720 birds (initial body weight 40.07 ± 0.05 g) were randomly distributed into four groups with six replicates per group and 30 birds per replicate. Four diets were formulated with 0% (CON), 200 mg/kg MLE (MLE200), 400 mg/kg MLE (MLE400) and 600 mg/kg MLE (MLE600) supplementation. Results showed that the addition of 200-600 mg/kg MLE to the diet significantly increased the body weight (BW) and average daily weight gain (ADG), but feed to gain ratio (F/G) were linearly decreased (p = 0.045) as dietary MLE increased. Birds fed MLE400 had higher (p < 0.05) total antioxidant capacity (T-AOC), interleukin-10 (Il-10), secretory immunoglobulin A (SIgA) and complement 3 (C3) contents than those fed CON, whereas MLE400 had lower malondialdehyde (MDA) content than CON (p < 0.05). Analysis of 16 S rDNA indicated that supplementation with 200 mg/kg MLE increased the Shannon indices in the caecum (p < 0.05). Supplementation with MLE decreased the abundance of the phylum Proteobacteria and genus Helicobacter, and increased the abundance of the phylum Bacteroidetes in the caecum in broiler chickens (p < 0.05). The drip loss rate in the MLE600 was significantly diminished (p < 0.05), whereas the shear force was significantly elevated (p < 0.05). In summary, dietary supplementation with MLE can effectively improve growth performance, intestinal immunity, serum antioxidant capacity, meat quality and intestinal microbiota of yellow feather broilers. The most appropriate MLE supplementation level was 400 mg/kg. This study provides a practical strategy for the dietary application of MLE in yellow feather broilers.

The effects of compound probiotics on production performance, rumen fermentation and microbiota of Hu sheep.

Fungal probiotics have the potential as feed additives, but less has been explored in ruminant feed up to date. This study aimed to determine the effect of compound probiotics (CPs) with Aspergillus oryzae 1, Aspergillus oryzae 2 and Candida utilis on Hu sheep's growth performance, rumen fermentation and microbiota. A total of 120 male Hu sheep, aged 2 months and with the body weight of 16.95 ± 0.65 kg were divided into 4 groups. Each group consisted of 5 replicates, with 6 sheep per replicate. Group A was the control group fed with the basal diet. Group B, C and D was supplemented with the basal diet by adding 400, 800 and 1,200 grams per ton (g/t) CPs, respectively. The feeding trial lasted for 60 days after a 10-day adaptation period. The results showed that the average daily gain (ADG) of sheep in the CPs groups were significantly higher, the feed/gain were significantly lower than those in group A in the later stage and the overall period. The addition of CPs increased the economic benefit. The levels of CD4+ and the CD4+/CD8+ ratio in the CPs groups were higher than those in Group A. The levels of GSH, IgG, IL-2, IL-6, and IFN-γ in group C were significantly elevated compared with group A. Group B showed a significant increase in rumen NH3-N and cellulase activity. There was no difference in VFAs content between group A and group B, however, with the increasing addition of CPs, the butyric acid and isobutyric acid content tended to decrease. The rumen microbiota analysis indicated that the CPs addition increased the Firmicutes and Proteobacteria abundances, decreased the Bacteroidetes abundance. The correlation analysis showed that Prevotella was negatively correlated with ADG, and the addition of 400 CPs in group B reduced Prevotella's relative abundance, indicating CPs increased sheep growth by decreasing Prevotella abundance. The CPs addition reduced caspase-3, NF-κB and TNF-α expression in liver, jejunum and rumen tissues. In conclusion, the addition of CPs increased the sheep production performance, reduced inflammation, improved rumen and intestinal health. Considering the above points and economic benefits, the optimal addition of CPs as an additive for Hu sheep is 800 g/t.

Replacing Hydrolyzed Soybean Meal with Recombinant β-Glucosidase Enhances Resistance to Clostridium perfringens in Broilers Through Immune Modulation.

Aglycone soy isoflavones have notable immune-regulatory bioactivity, while glycosidic forms in soybean meal pose challenges for absorption. β-Glucosidase (EC 3.2.1.21) catalyzes the non-reducing terminal β-d-glucosidic bonds, releasing β-d-glucan and aglycones. This study evaluated the impact of enzymatically hydrolyzed soybean meal (ESM) using recombinant β-glucosidase from Aspergillus niger on the growth performance and intestinal immune function of broilers under Clostridium perfringens infection. Prior to the feeding trial, soybean meal was enzymatically digested with recombinant β-glucosidase, ensuring almost complete conversion of glycosides to aglycones. After a week of pre-feeding, a total 180 healthy AA broilers were randomly assigned to three groups-control, semi-replacement of ESM (50% ESM), and full-replacement of ESM (100% ESM)-with 6 replicates of 10 chickens, and the trial lasted 28 days. On the 36th day, broilers were challenged with 1 mL of 1 × 1010 CFU/mL Clostridium perfringens (Cp) via gavage for 3 days. The results showed that the substitution of ESM had no effect on the body weight gain of broilers but significantly reduced the feed consumption and feed-to-gain ratio (p < 0.01). The study revealed that Cp significantly disrupted jejunal morphology, while ESM significantly mitigated this damage (p < 0.05). Real-time PCR results demonstrated that compared to the Cp group, ESM restored Cp-induced intestinal barrier impairments (e.g., Occludin, Claudin-1, Muc2), normalized aberrant cellular proliferation (PCNA) and apoptosis (Caspase-1 and Caspase-3), and upregulated the expression of anti-inflammatory factor Il-10 while suppressing pro-inflammatory cytokines (Il-1β, Il-6, and Il-8) (p < 0.05). Moreover, flow cytometry analyses demonstrated that ESM promoted Treg cell-derived Il-10, which alleviated macrophage-derived inflammation. Substituting conventional soybean meal with β-glucosidase, enzymatically treated, significantly reduced feed consumption and alleviated the intestinal damage and immune dysfunctions induced by Clostridium perfringens infection in broilers.

Protective Effect of Enterococcus faecium and Its Extracellular Vesicles Against Ethanol-Induced Intestinal Injury.

In this study, we examined the impact of Enterococcus faecium (E. faecium, Efm) and its extracellular vesicles (EVs) on intestinal morphological structure, antioxidant function, inflammatory response, and permeability in rats. In a 5-day feeding experiment, a total of 72 female Sprague Dawley (SD) rats were randomly allotted into nine groups with eight rats per group. The study was conducted in three parts. First, we examined the impact of Efm on ethanol-induced intestinal injury. Second, we investigated the protective effects of various active components of bacterial culture on intestinal function invivo. Third, we explored the impact of Efm with elevated EV secretion on intestinal function. The rats were treated by gavage administration (5 mL/kg body weight [BW]) every other day for a total of three times. After the last treatment at 2 h, the phosphate buffered saline (PBS)group received 5 mL/kg BW of PBS orally, whereas the other groups were orally administered 5 mL/kg BW of absolute ethanol to induce intestinal injury. After the feeding trial, eight rats per treatment were collected for intestinal samples. Our findings demonstrate that pretreatment with Efm can reverse morphological alterations in intestinal tissues, enhance superoxide dismutase/malondialdehyde levels, increase intestinal permeability, and reduce the inflammation levels, thereby regulating intestinal damage. Pretreatment with EfmEVs reversed the detrimental effects of ethanol-induced intestinal damage, displaying a discernible decline in inflammation, augmented permeability, and bolstered antioxidant capacity. Moreover, the release of EVs contributes to the intestinal safeguarding mechanism of Efm. EVs act as mediators in Efm's protective response against ethanol-induced intestinal injury by mitigating inflammation and enhancing antioxidant activity. The Clinical Trial Registration Number: FOSU210403.

Growth, Nutrient Deposition, Plasma Metabolites, and Innate Immunity Are Associated with Feeding Rate in Juvenile Starry Flounder (Platichthys stellatus).

A 10-week feeding trial was conducted to evaluate the effects of different feeding rates on growth performance, nutrient deposition, plasma metabolite, and immunity of juvenile starry flounder. Fish (initial mean body weight, 183.6 ± 2.3 g) were subjected to eight feeding rates (0.4, 0.8, 1.2, 1.6, 2.0, 2.4, 2.8, and 3.2% body weight/day [BW/d]) with a commercial diet containing 53.5% crude protein and 10.2% crude lipid. After the feeding trial, fish growth increased significantly (p < 0.05) from 0.4% to 2.0% BW/d, with no significant differences being observed beyond 2.0% BW/d. Protein and lipid gains in the whole body and liver of the fish fed 2.0-3.2% BW/d were significantly (p < 0.05) higher than those of the fish fed 0.4% and 0.8% BW/d. Conversely, protein retention in the whole body and the liver decreased with an increased feeding rate. Lysozyme activity was significantly (p < 0.05) higher in the fish fed 1.6-2.8% BW/d than in those fed 0.4-1.2% BW/d. The best-fit model analyses for optimum feeding rate (OFR) revealed that the estimate for each parameter varied between 0.7% (feed conversion ratio) and 3.1% (lipid gain in carcass) BW/d. The OFR for productivity (weight gain) and enhanced innate immunity (lysozyme) were estimated at 2.4% and 1.7% BW/d, respectively.

Dietary vitamin E (α-tocopherol acetate) modulates growth, digestive enzymes, histopathology, and vulnerability of Nile tilapia, Oreochromis niloticus to Aeromonas hydrophila infection

Vitamin E is a fat-soluble vitamin that plays a vital function in several biological processes, and fish cannot synthesize it to meet their requirement. So, 56-day research was conducted to examine the influence of vitamin E (vit-E) (α-tocopherol acetate) on the Nile tilapia's growth, digestive enzymes, hematology, histology, and susceptibility to Aeromonas hydrophila. A total of 450 mono-sex Acclimated Nile tilapia (Oreochromis niloticus) were haphazardly dispersed into 30 aquaria, each with a capacity of 100 liters (15 fish/aquarium) to exemplify five groups with six replicates. A control diet (30 % protein) was enriched with 0.0 (E0), 150 (E150), 300 (E300), 600 (E600), and 1200 (E1200) mg/kg feed. Fish (13.5 ± 0.12 g) were given the trial diets until obvious satiation thrice daily for 56 days. At the end of the feeding trial, growth performance, digestive enzymes, hematology, and histology for the mid-intestine were examined. Subsequently, twenty fish from each treatment were challenged to contagion with Aeromonas hydrophila bacteria, and fish mortality was recorded for a further 14 days. At the end of the bacterial challenge, histology for the mid-intestine, liver, and spleen tissues was examined. Growth performance, feed utilization, and digestive enzyme secretion (proteases, lipase, and α-amylase) were substantially (P < 0.5) improved with raising vit-E levels in fish feeds up to E1200. Increasing the vit-E doses improved fish gut histomorphology by increasing the count and size of intestinal folds bordered by well-arranged enterocytes. The body composition was not influenced by dietary vitamin E, except lipid content, which increased substantially as vitamin E levels increased. Fish fed with vita-E enriched diets had higher resistance to A. hydrophila infection; however, the control group exhibited the greatest fish mortality rate (80 %), while the lowest rate was observed at E1200 (30 %). Hepatic and spleen tissues in the control group (E0) showed severe congestion and degeneration, whereas vit-E-treated fish groups progressively recovered normal histomorphology depending on the vit-E doses. Finally, this research recommends feeding Nile tilapia on vit-E, particularly 1200 mg/kg feed, to enhance its performance, welfare status, and resistance to A. hydrophila contagion.

Targeted metabolomics analysis of fatty acids in lamb meat for the authentication of paper mulberry silage as a substitute for alfalfa silage

BackgroundThe paper mulberry (Broussonetia papyrifera L.) is a valuable source of woody forage that can be used for ruminants, such as goat and lambs. However, there is limited knowledge about how paper mulberry silage affects carcass characteristics, meat physicochemical attributes, amino acid and unsaturated fatty acids in Hu lambs compared to alfalfa silage. The objective of this experiment was to investigate the impact of substituting alfalfa silage with paper mulberry silage on the slaughter performance, meat quality, free amino acid and fatty acid composition in muscles of Hu lambs.ResultsThirty 60-day-old male Hu lambs with 17.13 ± 0.26 kg body weight were randomly allocated into paper mulberry silage (30% of total mixed ration) and alfalfa silage (30% of total mixed ration) treatment, and the feeding trial lasted 70 days. The results indicated no significant differences in all measurements (P > 0.05). However, compared to the group fed with alfalfa silage, the group fed with paper mulberry silage exhibited a reduction in meat drip loss (P < 0.05) without any notable effect on meat nutrients (P > 0.05). Targeted metabolomics analysis revealed that feeding paper mulberry silage led to decreased levels of certain bitter amino acids, such as valine, leucine, isoleucine, tryptophan, and phenylalanine (P < 0.05). Furthermore, the consumption of paper mulberry silage significantly augmented the levels of monounsaturated and polyunsaturated fatty acids, particularly n6-polyunsaturated fatty acids (C18:2n6, C20:3n6, C20:4n6, etc.), in meat.ConclusionsSubstituting paper mulberry silage for alfalfa in the daily diet of Hu lambs not only has no detrimental effect on animal performance but also improves meat unsaturated fatty acid composition.Graphical

Dietary full-fat or defatted black soldier fly larvae can replace protein sources with no detrimental effect on growth performance or intestinal health of nursery pigs.

This work aimed to determine the effects of dietary full-fat or defatted black soldier fly larvae (BSFL) to replace protein sources on growth performance, blood parameters, intestinal morphology, and intestinal microbiota in nursery pigs and to investigate the effects of dietary defatted BSFL at up to 30% at the expense of protein sources on growth performance in nursery pigs. In Exp. 1, a total of 36 barrows with an initial body weight of 7.0kg (standard deviation = 0.8) were allotted to 3 dietary treatments in a randomized complete block design with 4 replicate pens per treatment and 3 barrows per pen. A corn-soybean meal (SBM)-whey-based control diet was prepared with soy protein concentrate and fish meal as additional protein supplements. Two additional diets were prepared to include 20% full-fat BSFL or 20% defatted BSFL to replace soy protein concentrate and fish meal to maintain the same energy and nutrient concentrations in all diets. In the 28-day feeding trial, pigs fed the diet containing defatted BSFL tended to consume more feeds (P < 0.10) than other groups during days 14 to 28 and the overall period. On day 28, the serum blood urea nitrogen in pigs fed the control diet was less (P < 0.05) than that fed the full-fat or defatted BSFL, but fecal score and jejunal morphology did not differ among the treatment groups. Relative abundance of Mycoplasma in the ileal digesta was less (P < 0.05) in the pigs fed the diet containing full-fat or defatted BSFL compared with the control group. In Exp. 2, a total of 192 pigs with an initial body weight of 7.8 (standard deviation = 1.2kg) were randomly allotted to one of 4 dietary treatments in a randomized complete block design with 6 replicate pens per treatment and 4 barrows and 4 gilts per pen. A control diet was mainly based on corn, SBM, fermented SBM, fish meal, and spray-dried plasma protein. Three additional diets were prepared to contain 10%, 20%, and 30% defatted BSFL to replace SBM, fermented SBM, fish meal, and spray-dried plasma protein to maintain for the same energy and nutrient concentrations. Average daily gain, average daily feed intake, gain:feed, and fecal score were not affected by increasing dietary defatted BSFL. Overall, dietary black soldier fly larvae did not compromise growth performance or intestinal health in nursery pigs. Black soldier fly larvae can be used in nursery pig diets to replace other protein sources without negative effects.

Effects of Dietary Inclusion of Enzymatically Hydrolyzed Compound Soy Protein on the Growth Performance and Intestinal Health of Juvenile American Eels (Anguilla rostrata).

The enzymatic hydrolysis of soybeans could enhance their application as an ingredient and alternative to fishmeal in aquafeeds. Here, a 10-week feeding trial was conducted to evaluate the impacts of different dietary inclusion levels of enzymatically hydrolyzed compound soy protein (EHCS) on the growth performance and intestinal health of juvenile American eels (Anguilla rostrata). Five experimental diets were formulated with graded EHCS inclusion levels at 0% (EHCS0), 8% (EHCS8), 16% (EHCS16), 24% (EHCS24), and 32% (EHCS32). Each diet was randomly assigned to four replicate tanks. The results showed that eels fed the EHCS8 diet exhibited superior growth performance, decreased serum lipid content, and increased immunity compared to those fed the EHCS0 diet. Eels fed the EHCS8 diet also displayed improved intestinal histology, enhanced antioxidant capacity and balance of intestinal microbiota as well as an enhanced proliferation of probiotics compared to those receiving the EHCS0 diet. Compared with eels fed the EHCS0 diet, those fed the EHCS16 diet exhibited comparable growth performance and values for the aforementioned markers. The quadratic regression analysis of weight gain rate and feed efficiency against the dietary EHCS inclusion levels determined the maximum levels of dietary EHCS inclusion for American eels range from 17.59% to 17.77%.

A wearable real-time particulate monitor demonstrates that soaking hay reduces dust exposure.

Affordable particulate matter (PM) monitors suitable for use on horses will facilitate the evaluation of PM mitigation methods and improve the management of equine asthma. Calibrate a real-time wearable PM monitor (Black Beauty [BB]) and compare the PM exposures of horses fed dry or soaked hay. Laboratory calibration; complete cross-over feed trial. Side-by-side sampling with BB monitors and tapered element oscillating microbalances (TEOMs) was performed under varying concentrations of PM from alfalfa hay. Linear regression was used to derive a calibration formula for each unit based on TEOM PM measurements. Precision was evaluated by calculating the coefficient of variation and pairwise correlation coefficients between three BB monitors. PM exposure was measured at the breathing zone of 10 horses for 8 h after they were fed dry or soaked hay. Repeated measures generalised linear models were constructed to determine the effect of hay treatment and measurement duration (initial 20-min vs. 8-h) upon exposure to PM with diameters smaller than or equal to 10 μm (PM10) and 2.5 μm (PM2.5). BB monitor PM2.5 and PM10 measurements were linearly correlated with TEOM data (coefficient of determination r2 > 0.85 and r2 > 0.90 respectively), but underestimated PM2.5 mass concentrations by a factor of 4 and PM10 concentrations by a factor of 44. Measures from the three BB monitors had a coefficient of variation <15% and pairwise r > 0.98. Feeding soaked hay significantly reduced average PM2.5 exposures (20-min: dry: 160 μg/m3, soaked: 53 μg/m3, p < 0.0001; 8-h: dry: 76 μg/m3, soaked: 31 μg/m3, p = 0.0008) and PM10 exposures (20-min: dry: 2829 μg/m3, soaked: 970 μg/m3, p < 0.0001; 8-h: dry: 1581 μg/m3, soaked: 488 μg/m3, p = 0.008). No health outcome measures were collected. With appropriate corrections, the BB monitor can be used to estimate horse PM exposure. While 20-min measurements yielded higher estimates of exposure than 8-h measurements, both intervals demonstrate that soaking hay reduces PM exposures by more than 50%.

Statistical modelling of growth curve for longitudinal data on a feeding trial in goat breeds

The growth curve parameters were estimated extending a linear regression to higher degree polynomial with attempts to use also the biologically appealing Gombertz function. The data contained monthly weight records from weaning to the age of 14 months of kids in two Omani goat breeds Sahrawi and Jabbali used in a feeding trial assessing the effect of concentrate supplement (14% crude protein). The growth curve parameters were estimated within the fixed effects breed and feed concentrate level (2 or 3% of live body weight) with an extension to mixed models using animals as random effects. The parameters and model contrasting were performed with ML or REML as appropriate with relative comparison relying on AIC and significance testing of estimated parameters. The mixed model analyses were performed with publicly available R software package programs. The fixed effect cubic regression with linear random effect model fitted into the data. The higher level of concentrates improved the immediate post-weaning growth in the same way in the breeds while the subsequent growth curve differed with more pronounced weight increments in the Jabbali breed.

The effect of experimental diets incorporating fermented soybean meal on growth metrics and utilization of nutrients in broiler chickens

The aim of this study was to explore the impact of fermented soybean meal (FSBM) on the nutritional quality of feed, growth performance indicators, and nutrient utilization in broiler chickens, aiming to overcome the challenges associated with locally produced soybean meal stemming from anti-nutrients and variations in nutritional quality. The study methodology included assessing growth performance metrics through two-way ANOVA statistical analysis and evaluating nutrient utilization in broiler chickens. Results indicated that broiler chickens fed with FSBM exhibited superior performance, displaying the highest average weekly weight gain (452 grams), optimal feed conversion ratio (1.39), extended intestinal length (225 cm), increased intestinal weight (297.5 grams), and heightened activity of digestive enzymes compared to other treatment groups throughout the feeding trials. The results of this study suggest that FSBM’s better digestibility helps broiler chickens grow faster. This makes it a possible replacement for animal protein sources like fish meal in poultry feed production, which is good for both local poultry feed producers and consumers.

The need for high-resolution gut microbiome characterization to design efficient strategies for sustainable aquaculture production

Microbiome-directed dietary interventions such as microbiota-directed fibers (MDFs) have a proven track record in eliciting responses in beneficial gut microbes and are increasingly being promoted as an effective strategy to improve animal production systems. Here we used initial metataxonomic data on fish gut microbiomes as well as a wealth of a priori mammalian microbiome knowledge on α-mannooligosaccharides (MOS) and β-mannan-derived MDFs to study effects of such feed supplements in Atlantic salmon (Salmo salar) and their impact on its gut microbiome composition and functionalities. Our multi-omic analysis revealed that the investigated MDFs (two α-mannans and an acetylated β-galactoglucomannan), at a dose of 0.2% in the diet, had negligible effects on both host gene expression, and gut microbiome structure and function under the studied conditions. While a subsequent trial using a higher (4%) dietary inclusion of β-mannan significantly shifted the gut microbiome composition, there were still no biologically relevant effects on salmon metabolism and physiology. Only a single Burkholderia-Caballeronia-Paraburkholderia (BCP) population demonstrated consistent and significant abundance shifts across both feeding trials, although with no evidence of β-mannan utilization capabilities or changes in gene transcripts for producing metabolites beneficial to the host. In light of these findings, we revisited our omics data to predict and outline previously unreported and potentially beneficial endogenous lactic acid bacteria that should be targeted with future, conceivably more suitable, MDF strategies for salmon.

Effect of Bacillus amyloliquefaciens supplementation on intramuscular fat accumulation and meat quality in finishing pigs.

This study evaluated the potential of Bacillus amyloliquefaciens to improve growth performance and meat quality in finishing pigs. Thirty-two female Landrace × Duroc pigs, 21 weeks old with initial body weight 77.45±3.29 kg, were divided into two groups: a control group (basal diet) and a probiotic group (basal diet with Bacillus amyloliquefaciens at 1×109 CFU/kg). Body weight and average daily gain (ADG) were recorded at the start and at fortnight intervals for a 56-d feeding trial. At the end of the experiment, carcass traits, meat quality and intramuscular fat related gene expression of longissimus dorsi muscle were analyzed. The probiotic group showed significantly higher final body weight and D0-D56 ADG (p < 0.05). Additionally, the probiotic group had greater carcass weight, back fat thickness and marbling score (p < 0.05), while the lean meat percentage remained unchanged. Meat quality analysis revealed that the probiotic group had a higher b* value (5.47) (p < 0.05), and a lower shear value (p < 0.001), but there was no effect on the a* value and water holding capacity. Moreover, probiotic treatment increased the gene expression of fatty acid uptake and regulator, such as LPL, CD36, and SLC27A1 (p < 0.05). Our findings suggest that the supplementation of Bacillus amyloliquefaciens not only enhanced growth performance and carcass weight in finishing pigs, but also improved marbling and tenderness in the longissimus dorsi muscle through the up-regulation of lipogenic-genes related to fat accumulation. This indicates its potential as feed additive to enhance pork quality.

Using Azolla (Azolla microphylla) leaf meal and phytonutrient powder on rumen fermentation efficiency and nutrient degradability using in vitro technique.

This work was to investigate the effect of using Azolla (Azolla microphylla) leaf meal and phytonutrient powder on rumen fermentation efficiency and nutrient degradability using in vitro technique. All respective treatments were imposed in a 2 × 4 × 2 Factorial arrangements according to a completely randomized design (CRD). The first factor was two ratios of roughage to concentrate (R:C at 60:40, and 40:60), the second factor was Azolla (Azolla microphylla) powder (AMP) supplementation levels (0%, 3%, 6%, and 9% of the total substrate) and the third factor was Turmeric (Curcuma longa) powder (TUP) supplementation levels (0% and 2% of the total substrate). Cumulative gas production at 96 h, was affected by R:C and numerically increased by AMP and TUP supplementation (p<0.05). Gas production kinetics increased with the increasing ratio of concentrate and AMP supplementation whereas TUP supplement reduced gas production. In vitro DM degradability was remarkably increased (p<0.05) by the R:C ratio, AMP and TUP supplementation. However, increasing R:C ratio, AMP and TUP supplementation resulted in the concentration of propionate (C3) significantly increasing (p<0.05). Acetate (C2), C2:C3 ratio, and protozoal population were improved (p<0.05), while the methane production decreased. Under this study, the results were obtained under the supplementation level of 9% AMP and 2% TUP of total substrate, hence, the combined use is potentially beneficial. These results revealed a potential use of AMP and TUP as a supplement to improve rumen fermentation for ruminant feeding. Nevertheless, in vivo feeding trials should be further investigated using AMP and TUP as a source of protein and phytonutrient.

Effect of dietary glycerol monolaurate supplementation on gene expression, intestinal mucosa and microbiota of juvenile black sea bream (Acanthopagrus schlegelii).

Glycerol monolaurate (GML) is a chemical compound derived from the combination of lauric acid and glycerol, exhibiting potent antimicrobial properties. An eight-week feeding trial was conducted to evaluate the effects of dietary supplementation of Glycerol Monolaurate (GML) on juvenile black sea bream. The control diet included 24% fish meal, while five additional diets were formulated with increasing GML concentrations: 0.01% (GML1), 0.02% (GML2), 0.04% (GML3), 0.08% (GML4), and 0.16% (GML5). Each diet was assigned to triplicate tanks. At the end of the experiment, serum immune and antioxidant in liver were non-significantly different among the groups. The relative gene expression of IGF-1 and GH in liver was statistically higher in the GML3 treated. The relative gene expression of IL-1, TGF, TNF-1, CCK, CLDN1, CASS-3 and GPR41 in intestine were statistically higher in the GML3 group. The photomicrographs of transmission electron microscope of the intestine were also studied. The GML supplemented groups had longer brush borders. The cells seemed to be joined by an intact junctional complex without visible intercellular spaces. The observed variations in phyla, class, and genus did not demonstrate statistical significance. Proteobacteria, Cyanobacteria, Firmicutes and Actinobacteria in the phylum, and Oxyphotobacteria, Bacteroidia, Holophagae and Negativicutes in the class, Brevundimonas, and Achromobacter in the genera were all substantially increased with higher levels of GML supplementation. Based on these results, it is suggested that glycerol monolaurate (GML) may serve as a potential dietary supplement for promoting different gene expression and intestinal health in black sea bream.

Effects of freshness of poultry by-product meal on the growth performance, immune response, and hepatopancreatic health of Macrobrachium rosenbergii

A 73-day feeding trial was conducted to determine the effects of the freshness of poultry by-product meal on the growth performance, immune response and hepatopancreatic health of giant freshwater prawn, Macrobrachium rosenbergii. Three semi-purified diets were formulated containing 2.5 % poultry by-product meal with different TVB-N value, designated as L group (untreated poultry by-product meal, TVB-N 10 mg/100 g, i.e., dietary TVB-N 55 mg/100 g), M group (TVB-N 300 mg/100 g, i.e., dietary TVB-N 60 mg/100 g), and H group (TVB-N 450 mg/100 g, i.e., dietary TVB-N 68 mg/100 g), and fed to three groups of prawns (initial weight: 0.82 ± 0.01 g), respectively. Results showed that the weight gain rate (WGR) and specific growth rate (SGR) of prawns significantly decreased with the TVB-N value increased (P < 0.05). The survival rate (SR) and hepatosomatic index (HSI) of prawns in group M and group H were significantly decreased (P < 0.05), while the feed conversion ratio (FCR) was significantly increased (P < 0.05). In addition, the lipase (LPS) and α-amylase (α-AMS) activity of prawns in group L was significantly higher than that in group H (P < 0.05). With the poultry by-product meal TVB-N value increased, the activity of total superoxide dismutase (T-SOD) and glutathione S-transferase (GST) was significantly decreased. RT-qPCR results showed that the expression of bok in group H was significantly higher than that in group L and group M (P < 0.05), the expressions of caspase3, caspase9, bax, and nf-κb in group H were significantly higher than that in group L (P < 0.05). High temperature stress and ammonia nitrogen stress significantly decreased the cumulative survival rate of prawns in group M and group H. Conclusively, it is necessary to guarantee the freshness of the ingredients in prawn formulated diets, and the TVB-N value of diets is recommended not to exceed 60 mg/100 g.

Protein quality malnutrition.

Protein quality refers to the evaluation of a food or a diet based on its amino acid composition, protein digestibility, and protein bioavailability. When these parameters are specified, either through direct measurement or estimation, the amino acids provided by the diet are compared to those required by a healthy individual, and based on this comparison, an adequacy ratio or score is assigned. Two widely used protein quality scoring systems are the protein digestibility-corrected amino acid score (PDCAAS) and the digestible indispensable amino acid score (DIAAS), neither of which account for the dietary source of the protein. In malnourished children, metabolic adaptations reduce the endogenous availability of amino acids and increase the demand for protein synthesis. These increased amino acid requirements are primarily driven by the presence of acute infection and the need for tissue accretion. This review examines two large clinical feeding trials involving moderately malnourished children, where dietary protein quality was carefully measured. The finding s suggest that protein quality scores alone do not reliably predict weight gain or recovery in these children and that consuming milk protein provides distinct advantages over vegetable-based proteins.

Effects of different feeding patterns on growth, enzyme activity, and intestinal microbiome of the juvenile Pacific abalone Haliotis discus hannai

In northern China, the predominant food sources for abalone farming include fresh kelp, salted kelp, and formulated diets, and abalone can also endure prolonged starvation when food is scarce. While there is a dearth of comprehensive investigation into the effects of these feeding patterns on the temporal dynamics of enzyme activity, and intestinal microbiome of abalone. In this study, a total of 3600 juvenile Pacific abalones were allocated to 12 tanks, randomly divided into four groups based on the feeding patterns: fresh kelp (labeled as FK), salted kelp (SK), formulated feed (FF), and starved group (S). After a 60-day feeding trial, the results showed that abalone in the FK, SK, and FF groups exhibited significant positive effects on both weight and shell growth compared to the S group (P<0.05). Notably, the FF group displayed the highest values of the growth performance. The activity of digestive enzymes and antioxidant enzymes in the FF group had an up-regulated trend over the course of feeding trial, whereas amylase and lipase activity in abalone declined along with starvation. Moreover, the microbial Shannon index showed an overall decreasing trend over time in the FF, FK, and SK groups except for the S group. The ANOSIM analysis revealed that both feeding pattern and cultivating time significantly influenced the structure of the microbial communities. Across the feeding trial, Proteobacteria, Fusobacteriota, and Firmicutes were identified as the dominant phyla in the intestinal microbiome of abalone under different feeding patterns. The core genera were Psychrilyobacter, Mycoplasma, and Vibrio. Additionally, the neutral model analysis revealed that stochastic processes both play a key role in shaping the assembly of microbial communities in different feeding patterns. This study could offer valuable insights into the impact of different feeding patterns on growth and physiology of abalone, thereby contributing to the enhancement of management strategies in the northern Chinese abalone aquaculture industry.

Dietary administration of Bacillus amyloliquefaciens AV5 on antioxidant activity, blood parameters, and stress responses of Nile tilapia (Oreochromis niloticus) raised under hypoxia and temperature variability

The ability of Nile tilapia to tolerate hypoxia, as well as low and high temperatures, presents a significant economic concern, as it adversely affects their growth and leads to increased mortality rates. A 42-day feeding trial was conducted to evaluate the impact of adding Bacillus amyloliquefaciens AV5 to a fish meal on the physiological response of Nile tilapia. Three meals were administered to fish (23.4 ± 0.3g) in triplicates. The diets included GC (without B. amyloliquefaciens AV5), G1 (106 cfu/g), and G2 (108 cfu/g). After the treatment trial, we assessed the antioxidant parameters, hemato-immunological indices, and stress-related genes in O. niloticus. Subsequently, we subjected the fish to hypoxia for 20h and low and high temperatures for 3h each. The findings demonstrated a significant rise in white blood cells, red blood cells, haemoglobin, and hematocrit levels in the blood of fish that were fed a meal supplemented with B. amyloliquefaciens AV5, compared to the control group (GC) (P<0.05), the serum of all fish groups that were supplemented with B. amyloliquefaciens AV5 exhibited an increase in catalase, total antioxidant capacity and superoxide dismutase activity and a decrease in lactate dehydrogenase, alanine aminotransferase, aspartate aminotransferase, pyruvate kinase, myeloperoxidase, glucose, cortisol (P < 0.05). In addition, all fish diet groups that received B. amyloliquefaciens AV5 as a supplement exhibited elevated levels of HIF-1α and HSP70 expression in their livers (P<0.05). Nile tilapia in the G2 diet, exhibited improved values in most evaluated indices under various stress settings (P<0.05). These data indicate that the G2 supplement may be used as a preventive measure to weaken the impacts of environmental stress on O. niloticus.