Modulation of the growth performance, meat composition, oxidative status, and immunity of broilers by dietary fulvic acids

Effects of fulvic acid on broiler performance, blood biochemistry, and intestinal microflora

To study the effects of mineral fulvic acid (FuA) on broiler performance, slaughter performance, blood biochemistry index, antioxidant function, immune performance, and intestinal microflora, 360 Arbor Acres (AA) broiler chickens with similar body weights were randomly divided into 5 groups with 6 replicates in each group and 12 chickens in each replicate in the current study. Chickens in the control group (C) were fed with the basal diet, and chickens in the test groups (I, II, III, and IV) were fed with the diet supplemented with 0.05%, 0.1%, 0.2%, and 0.3% mineral FuA, respectively. The indicators were measured on the hatching day, d 21 and d 35. From the whole experimental period, FuA supplement significantly increased average body weight (ABW) (P < 0.05), average daily gain (ADG) of broilers (P < 0.05), and thymus weight (P < 0.05) in II and IV groups, but bascially reduced the pH value of thigh meat. FuA supplement significantly improved aspartate aminotransferase (AST) activity in the group III on d 35 (P < 0.05) and the serum levels of IgA and IgG on d 21 and d 35 (P < 0.05), but reduced glutathione peroxidase (GSH-Px) level on d 21 (P < 0.05) and malondialdehyde (MDA) level in serum on d 35 (P < 0.05). FuA supplement significantly affected the abundance of Barnesiella, Lachnospiraceae, Alistipes, Lactobacillus, and Christensenellaceae on genus level. Differences between group III and other groups were significant in the genera microflora composition on d 21 and d 35. Functional analysis showed that the cecum microbiota were mainly enriched in carbohydrate metabolism, amino acid metabolism, and energy metabolism. In conclusion, FuA may potentially have significant positive effects on the growth performance and immune function of AA chickens through the modulation of the gut microbiota, and the 0.1% FuA was the best in broiler diet based on the present study.

Dietary fulvic acid supplementation improves the growth performance and immune response of sea cucumber (Apostichopus japonicas)

The present study aims to explore the effects of dietary fulvic acid (FA) supplementation on the growth performance, digestive enzyme activity and immune response of sea cucumber (Apostichopus japonicas). FA was used to replace 0 (control), 0.1, 0.5 and 1 g cellulose in the basic diet of sea cucumber to formulate four experimental feeds with equivalent nitrogen and energy denoted as F0, F0.1, F0.3 and F1, respectively. No significant differences were observed in the survival rate among all groups (P > 0.05). Results show that the body weight gain rate, specific growth rate, intestinal trypsin, amylase and lipase activities, serum superoxide dismutase, catalase, lysozyme, alkaline and acid phosphatase activities and disease resistance ability against the pathogen, Vibrio splendidus of the sea cucumbers fed with FA-containing diets were significantly higher than those of the control group (P < 0.05). The optimum dose of dietary FA supplementation required for the maximum growth of sea cucumber was 0.54 g/kg. Therefore, dietary FA supplementation to the feed of sea cucumber can significantly improve its growth performance immune response.

Effects of supplemental fulvic acid on survival, growth performance, digestive ability and immunity of large yellow croaker (Larimichthys crocea) larvae

A 30-day feeding trial was designed to evaluate the effect of supplemental fulvic acid (FA) on survival, growth performance, digestive ability and immunity of large yellow croaker (Larimichthys crocea) larvae (initial body weight 11.33 ± 0.57 mg). Four isonitrogenous and isolipids diets containing 0.00%, 0.01%, 0.02% and 0.04% FA were formulated, respectively. Results showed that the supplementation of 0.04% FA significantly improved survival rate of large yellow croaker larvae. Meanwhile, supplemental FA significantly increased final body weight and specific growth rate. Based on the specific growth rate, the optimal supplementation was 0.0135% FA. Larvae fed the diet with 0.01% FA had significantly higher villus height than the control. The supplementation of 0.01%–0.02% FA significantly increased the muscular thickness of intestine. Moreover, supplementation of FA significantly increased mRNA expression of intestinal epithelial proliferation and barrier genes (pcna, zo-1 and zo-2). Diets supplemented with 0.02%–0.04% FA significantly increased the activity of trypsin in the intestinal segment, while 0.01%–0.02% FA significantly increased the activity of trypsin in the pancreatic segment. Compared with the control, supplementation of FA remarkably increased activities of alkaline phosphatase and leucine aminopeptidase in the brush border membrane of intestine. Larvae fed the diet with 0.01% FA significantly increased activities of lysozyme and total nitric oxide synthase. Furthermore, the supplementation of 0.01% to 0.02% FA significantly decreased the mRNA expression of pro-inflammatory cytokines (tnf-α and il-6). Concurrently, supplemental FA significantly increased anti-inflammatory cytokine (il-10) mRNA expression level. In conclusion, this study indicated that the supplementation of FA could improve the survival rate and growth performance of larvae by promoting intestinal development, digestive enzymes activities and innate immunity.

Ameliorative impacts of sodium humate on heat-stressed laying Japanese quail (Coturnix coturnix Japonica)

A total of 300 laying Japanese quails (230.10 ± 20 g body weight) divided into four groups (15 birds in 5 replicates/group) were used to examine the impacts of dietary sodium humate (SH) supplementation at levels of 0% (control diet), 0.2%, 0.4% and 0.6% on egg variables and physiological merits of laying quails for 10 weeks under heat stress conditions (15 June and 23 August 2021). Results showed 0.4% SH increased (p < 0.05) weight (12.27 vs. 11.91 g), production (79.84% vs. 69.20%), mass (597.13 vs. 510.48 g) and brokenness (2.8% vs. 5.4%) of eggs as compared to control. Egg shape, shell thickness, shell strength and cholesterol content as well as feed conversion ratio were higher (80.2, 295.8 µm, 1.468 kg/cm,² 11.08 mg/g and 2.69, p < 0.05) in 0.4% SH than in control group (75.2, 279.0 µm, 1.304 kg/cm,²  14.94 mg/g and 2.76). Feed intake, percentages of eggs' shells, yolk, albumen and serum biochemistry (total protein, albumin, AST and HDL) were not altered with the dietary SH. Birds fed on SH diets showed higher levels of globulin, calcium and phosphorus, as well as lower contents of albumin/globulin ratio, triglycerides, cholesterol, corticosterone compared with the control. Regression analysis of antioxidants expected higher total antioxidant capacity (TAC), superoxide dismutase, glutathione peroxidase at 0.35%, and glutathione at 0.40% SH, while the lowest concentration of malondialdehyde was computed at 0.45%. Similarly, immunoglobulins (IgG and IgM) maximum values were determined at 0.35% and 0.40% levels. Moreover, the concentration of tumour necrosis factor-alpha increased (p < 0.05) in all SH levels as compared to the control group. It is conceivable to conclude that the dietary implementation of SH at a level of 0.4% improved egg variables and well-being aspects of laying quail exposed to heat stress conditions.

Effects of fulvic acid addition on laying performance, biochemical indices, and gut microbiota of aged hens

The purpose of this study was to appraise the effect of fulvic acid on production, biochemical indices, and gut microbiota of laying hens. A total of 252 Dawu Golden Phoenix laying hens (55-week-old) were allotted to two treatments randomly, each with six replicates and 21 hens per replicate, including the control group (CG) and fulvic acid (500 mg/kg) group (FA). The trial period was 8 weeks. Adding FA raised egg weight (P = 0.03), shell-breaking strength (P = 0.03), and reduced egg breaking rate (P < 0.01), compared with CG. There was no difference in eggshell thickness and egg shape index between the two treatments; however, the FA group increased egg production by 1.45% and reduced the feed-to-egg ratio by 0.09. Moreover, dietary FA decreased the aspartate aminotransferase levels in serum (P = 0.04), and glutathione peroxidase and total antioxidant capacity were increased (P = 0.02 and 0.04, respectively). Despite this, the two groups had no differences in the alpha diversity indices (PD_whole trees, Shannon, Ace, Simpson, Chao1, and goods_coverage). Obviously, at the phylum level, the abundances of Firmicutes were improved (P < 0.01), Actinobacteriota (P < 0.01), and Proteobacteria (P < 0.01) were reduced by dietary FA. Supplementation with FA could improve the abundances of Megamonas (P < 0.01) and reduce Enterobacter (P < 0.01) at the genus level. To sum up, this study showed the addition of 500 mg/kg FA may boost production and egg quality and modulate the cecal microflora abundance and serum biochemical indices of laying hens.

Effects of fulvic acid on growth performance, serum index, gut microbiota, and metabolites of Xianju yellow chicken

Fulvic acid (FA) is a mixture of polyphenolic acid compounds extracted from humus, peat, lignite, and aquatic environments; it is used in traditional medicine to treat digestive tract diseases. The purpose of the present study was to investigate the effect of FA on growth performance, inflammation, intestinal microbiota, and metabolites in Xianju yellow chicken. The 240 Xianju yellow chickens (age, 524 days) included were randomly categorized into 4 treatments with 6 replicates per treatment and 10 birds per replicate. Birds received a basal diet or a diet supplemented with 500, 1,000, or 1,500 mg/kg of FA, for a period of 42 days. Dietary supplementation of FA improved average daily gain (ADG) and feed conversion ratio (FCR) (P > 0.05). Compared with the control group, the serum level of TNF-α in birds supplemented with FA was significantly decreased (P < 0.05), and that of IL-2 was significantly increased after administration of 1,500 mg/kg FA (P < 0.05). Analysis of gut microbiota indicated that FA reduced the relative abundance of genus Mucispirillum, Anaerofustis, and Campylobacter, but enriched genus Lachnoclostridium, Subdoligranulum, Sphaerochaeta, Oscillibacter, and Catenibacillus among others. Untargeted metabolomic analyses revealed that FA increased 7-sulfocholic acid, but reduced the levels of Taurochenodeoxycholate-7-sulfate, LysoPC 20:4 (8Z, 11Z, 14Z, 17Z), LysoPC 18:2, Phosphocholine and other 13 metabolites in the cecum. The results demonstrated that FA may potentially have a significant positive effect on the growth performance and immune function of Xianju yellow chicken through the modulation of the gut microbiota.

Influence of Sodium Humate on the Growth Performance, Diarrhea Incidence, Blood Parameters, and Fecal Microflora of Pre-Weaned Dairy Calves

This study aimed to evaluate the effects of the administration of sodium humate (NaH) on the growth performance, diarrhea incidence, and fecal microflora of pre-weaned Holstein calves. In a 53-day experiment, forty healthy newborn female calves were randomly allocated to the following four treatment groups: (1) control (basal diet); (2) 1-gram NaH (basal diet extra orally supplemented with 1 g of NaH dissolved in 100 mL of milk or milk replacer daily); (3) 3-gram NaH (basal diet extra orally supplemented with 3 g of NaH dissolved in 100 mL of milk or milk replacer daily); and (4) 5-gram NaH (basal diet extra orally supplemented with 5 g of NaH dissolved in 100 mL of milk or milk replacer daily). NaH was mixed with milk (d 2–20) or milk replacer (d 21–53). Calves in the 5-gram NaH group had a higher ADG during d 1 to 21 and d 21 to 53 than the other groups did (p < 0.05). Fecal scores and diarrheal incidence were significantly lower in the 3-gram and 5-gram NaH groups than the 1-gram NaH and control groups during d 1 to 20 (p < 0.05). The serum IgA, IgG and IL-4 concentrations, and T-SOD and T-AOC activities were higher, and the serum IL-6, TNF-α, D-lactic acid, and MDA concentrations were lower in the 5-gram NaH group than the control group (p < 0.05). Furthermore, NaH supplementation increased the abundances of Bifidobacterium and Lactobacillus but decreased the abundance of Escherichia coli in feces (p < 0.05). These encouraging findings indicated that supplementation with 5 g of NaH effectively improved the immune status, antioxidant capacity, and intestinal beneficial bacteria, and further improved the growth performance and reduced the diarrhea incidence of the pre-weaned dairy calves.

Addition of Different Levels of Humic Substances Extracted from Worm Compost in Broiler Feeds

Different sources and inclusion levels of humic substances (HS) have been tested in broiler rations as an alternative to the addition of growth promoter antibiotics (GPA) with promising results. The current study was carried out to assess the influence of HS extracted from worm compost on broiler production parameters, carcass yield, tibia characteristics, lactic acid bacteria (LAB) counts, excretion of Eimeria oocysts, and antioxidant status of breast meat. A total of 1200 broilers were used, housed in groups of 30 per pen, and assigned to five treatments: 1 = basal diet with GPA (positive control), 2 = basal diet without GPA (negative control), 3-5 = basal diet with 0.15, 0.30, and 0.45% HS, respectively. The data was subjected to a variance analysis and orthogonal contrasts. The FI decreased linearly (p < 0.05) from 1-14, 29-42, and 1-42 days as the inclusion of HS in the feed increased. The FCR had quadratic responses (p < 0.01) from 29-42 and 1-42 days concerning the HS inclusion levels. Lactic acid bacteria was higher (p ˂ 0.05) in ten-day-old chicks with 0.45% HS in the diet. The 1,1-diphenyl-2-picrylhydrazyl radical scavenging activity antioxidant potential decreased linearly (p < 0.05) concerning increasing HS in the feed. The results indicate that HS can be used as growth promoters in broiler feeds.

Combined supplementation of sodium humate and glutamine reduced diarrhea incidence of weaned calves by intestinal microbiota and metabolites changes

This study was conducted to investigate the effects of combined supplementation of sodium humate (HNa) and glutamine (Gln) on growth performance, diarrhea incidence, serum parameters, intestinal microbiome, and metabolites of weaned calves. In Exp. 1, 40 calves were randomly assigned to four treatments: 1) NC (negative control, basal diet), 2) 1% H+1% G (basal diet extra orally gavaged with 1 g of HNa and 1 g of Gln daily), 3) 3% H+1% G (basal diet extra orally gavaged with 3 g of HNa and 1 g of Gln daily), and 4) 5% H+1% G (basal diet extra orally gavaged with 5 g of HNa and 1 g of Gln daily). The HNa and Gln were together mixed with 100 mL of milk replacer (51 to 58 d of age) or water (59 to 72 d of age) and orally administrated to each calf from a bottle before morning feeding. In a 21-d trial, calves on the 5% HNa+1% Gln group had higher (P < 0.05) average daily gain (ADG) and lower (P < 0.05) diarrhea incidence than those in the control group. In Exp. 2, 20 calves were randomly assigned to two treatments fed with a basal diet and a basal diet supplemented with 100 mL of 5% HNa+1% Gln. In a 21-d trial, calves supplemented with HNa and Gln had higher (P < 0.05) ADG, IgG concentration and glutathione peroxidase (GSH-Px), and total antioxidant capacity (T-AOC) activities in the serum, but lower (P < 0.05) diarrhea incidence, as well as serum diamine oxidase (DAO), D-isomer of lactic acid (D-lac), tumor necrosis factor-α (TNF-α), and malondialdehyde (MDA) concentrations compared with control group. Results of intestinal microbiota indicated that supplementation with HNa and Gln significantly increased (P < 0.05) the abundance of intestinal beneficial microbiota. Moreover, supplementation with HNa and Gln altered 18 metabolites and enriched 6 Kyoto Encyclopedia of Genes and Genomes pathways in weaned calves. In conclusion, combined supplementation with HNa and Gln could decrease diarrhea incidence of weaned calves via altering intestinal microbial ecology and metabolism profile.

Effect of the Addition of Humic Substances as Growth Promoter in Broiler Chickens Under Two Feeding Regimens

Simple Summary

The rapid spread of antimicrobial-resistant genes in bacterial communities is a threat to human, animal, and environmental health that continues to progress inflexibly. Humic substances (HS) are promising complex molecules as an alternative to reduce the use of growth promoter antibiotics (GPA) in animal feeds. Improvements in productivity, intestinal health, immune response, and antioxidant status have been reported in broilers supplemented with HS. In the present study, broilers fed with an extract of HS (EHS) from a worm compost had similar carcass yield and excretion of coccidian oocysts but increased Clostridium perfringens and lactic acid bacteria (LAB) compared to broilers fed diets added with GPA. Broilers subjected to feed restriction had reduced growth performance and meat quality. These results confirm the growth-promoting effect of ESH, which could be explained by higher abundance of the beneficial LAB and by reducing the multiplication of harmful parasites in the gut of broilers.

Abstract

Humic substances (HS) from different sources have been evaluated to replace or reduce the use of growth promoter antibiotics (GPA) in the feeds of broiler chickens. The objective was to evaluate the growth performance, tibia measurements, nutrient balance, meat quality, and microbiological status of broiler fed with an HS extract (EHS) under ad libitum (ADLIB) or feed restriction (REST). Individually caged broilers (n = 180, 14–35 day of age) were assigned to a factorial arrangement of three dietary treatments: (1) positive control with bacitracin methylene disalicylate (BMD) and salinomycin; (2) negative control without BMD nor salinomycin, and (3) same as negative control with 0.25% EHS, and two feeding regimens 1) ADLIB or REST for 24 h on d 1, 7, and 14. Results were subjected to ANOVA. Positive control and EHS-fed broilers showed higher carcass yield (p < 0.05) and lower oocyst excretion (p < 0.01) compared to negative control birds. Lactic acid bacteria (LAB) and Clostridium perfringens (C. perfringens) were higher in negative control and EHS-broilers compared to positive control (p < 0.01). In conclusion, higher carcass yield, lower C. perfringens and oocyst excretion were found in positive control and higher carcass yield, higher LAB and lower oocyst excretion were found in EHS-fed broilers. Broilers subjected to REST had reduced growth performance and meat quality. In conclusion, EHS could be used to increase the carcass yield and beneficial LAB in broilers.