Effects of fulvic acid on growth performance and meat quality in growing-finishing pigs

The quality and nutritional value of beef from Angus steers fed different levels of humate (K Humate S100R)

This study compared the effect of four levels of K Humate S100R (potassium humate) supplementation on the quality, shelf-life, and nutritional properties of beef. Angus steers (n = 40) were individually housed and fed either 0, 35, 70, or 140 g K Humate S100R/animal/day for 100 days, following a 30 day adjustment period. The steers were slaughtered at the completion of the feeding study. The left m. longissimus lumborum (LL) was collected at 24 h post-mortem and aged for either 2 or 6 weeks before analysis. K Humate S100R supplementation did not affect beef drip loss, cooking loss, shear force, sarcomere length, ultimate pH, intramuscular fat content, or total volatile basic nitrogen concentrations (P > 0.05). Steers supplemented with 70 g/day K Humate S100R produced beef with higher a* values on Days 1 and 3 of retail display (P < 0.05). Beef mineral composition was unchanged by K Humate S100R supplementation (P > 0.05), but there were minor changes to the fatty acid profile. Specifically, the ratio of omega-6 to omega-3 (P < 0.05) and C20:2n-6 concentrations (P < 0.05) increased with supplementation level. Together, these results demonstrate no detrimental effects on beef quality and shelf-life as a result of K Humate S100R supplementation.

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.

Feeding Damascus goats humic or fulvic acid alone or in combination: in vitro and in vivo investigations on impacts on feed intake, ruminal fermentation parameters, and apparent nutrients digestibility

In vitro and in vivo experiments were carried out to investigate the effects of the supplementation of different levels of humic and fulvic acids alone or their combination (2:1 ratio) on ruminal fermentation constituents, and nutrients digestibility in goats. The treatments in Exp. 1 were the following: (1) basal substrate (50% concentrate: 50% forage) was incubated humic at 0, 2, 4, and 6 g/kg DM; (2) fulvic at 0, 1, 2, and 3 g/kg DM; and (3) a combination of humic and fulvic (in a 2:1 ratio) at 0, 3, 6, and 9 g/kg DM" of treatments. The results of Exp. 1 revealed that methane (CH4) production was linearly decreased (P < 0.001) upon increasing humic doses. Whereas, the combination of fulvic acid with humic acid resulted in a quadratic decrease (P < 0.001) in net CH4 production. Supplementing humic and fulvic acids, either separately or in combination, resulted in reduced (P < 0.05) ammonia nitrogen (NH3-N) and total volatile fatty acid (VFA) concentrations. In Exp. 2 to further examine the findings obtained in Exp. 1, forty Damascus non-lactating goats (2-3 years of age and body weight 29 ± 1.5 kg) were fed the same basal diet as in Exp. 1, plus one of four treatments. Treatments were the following: (1) control (no supplement); (2) basal diet plus 5 g humic alone; (3) basal diet plus 2.5 g fulvic alone, and (4) basal diet plus 7.5 g their combination. Goats fed diets supplemented with humic acid, fulvic acid, either alone or in combination, increased concentrations of butyrate (P = 0.003), total VFA (P < 0.001), and improved (P < 0.001) digestibility of nutrients, but reduced (P < 0.001) ruminal NH3-N concentrations. In conclusion, applying humic and fulvic acids alone or in combination attenuated in vitro CH4 production, while improved intake and diet digestibility without adverse effect on rumen fermentation profiles in Damascus goats.

The influence of L-proline and fulvic acid on oxidative stress and semen quality of buffalo bull semen following cryopreservation

BACKGROUND

This study investigates the effects of cryopreservation and supplementation of Azeri water buffalo's semen with proline (Lp) and fulvic acid (FA).

OBJECTIVES

Therefore, this study aimed to assess motility parameters, sperm viability, oxidative stress parameters, and DNA damage to detect the optimum concentrations of Lp and FA for buffalo semen cryopreservation.

METHODS

Thirty semen samples of three buffalo bulls were diluted in Tris-egg yolk extender and divided into 12 equal groups including control (C), Lp-10, Lp-20, Lp-40, Lp-60, Lp-80 (containing 10, 20, 40, 60, 80 mM L-proline, respectively), FA-0.2, FA-0.5, FA-0.8, FA-1.1, FA-1.4 and FA-1.7 (containing 0.2%, 0.5%, 0.8%, 1.1%, 1.4% and 1.7% fulvic acid, respectively).

RESULTS

The velocity parameters, TM and PM were improved by FA-1.7, FA-1.4, Lp-40 and Lp-60 groups compared to the C group but no significant difference was found regarding the amplitude of lateral head displacement and straightness compared to the control groups. The percentage of sperm viability and PMF were increased by FA-1.7, FA-1.4, FA-1.1, Lp-40 and Lp-60 groups compared to C group, while in terms of sperm DNA damage FA-1.7, FA-1.4, FA-1.1, Lp-10, Lp-20, Lp-40 and Lp-60 groups showed better results compared to C group. The results also showed that FA-1.7, FA-1.4, FA-1.1, Lp-20, Lp-40 and Lp-60 groups could improve TAC, SOD, GSH and decrease MDA levels. Also, FA-1.7, FA-1.4, Lp-20 and Lp-40 groups could improve GPx levels but just FA-1.7, and Lp-40 groups could improve CAT levels compared to C group.

CONCLUSIONS

Thus, it can be concluded that L-proline and fulvic acid supplementations can improve the quality parameters of post-thawed buffalo bull semen.

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.

Effects of sodium humate and glutamine on growth performance, diarrhoea incidence, blood parameters, and faecal microflora of pre-weaned calves

This study aimed to evaluate the effects of administration of sodium humate (HNa) and glutamine (Gln) on growth performance, diarrhoea incidence, serum parameters, and faecal microflora of pre-weaned Holstein calves. In a 57-day experiment, 28 healthy newborn female calves were randomly allocated to four treatment groups: (1) CON (control); (2) HNa (basal diet + 5% HNa); (3) Gln (basal diet + 1% Gln); and (4) HNa + Gln (basal diet + 5% HNa + 1% Gln). The calves in the CON group were fed with basal diet. HNa and Gln were alone or together mixed with milk (Days 1-20) or milk replacer (Days 21-57) and orally administered to each calf. The results indicated that calves combined supplemented with HNa and Gln had a higher average daily gain at 0-21 days, 21-57 days, and 0-57 days, and starter intake at 21-57 days and 0-57 days (p < 0.05). Compared with the CON group, calves in HNa, Gln, and HNa + Gln groups showed lower faecal scores and diarrhoea incidence at 0-21 days and 0-57 days (p < 0.05). Combined administration of HNa and Gln increased the concentration of IgG and IgA, activities of glutathione peroxidase (GSH-Px) and total antioxidant capacity (T-AOC) but decreased the concentration of diamine oxidase (DAO), D-lactic acid (D-lac), TNF-α, and malondialdehyde (MDA) in the serum of calves compared with the CON group throughout the entire period (p < 0.05). Furthermore, the abundances of Bifidobacterium and Lactobacillus were increased but the Escherichia coli was decreased in faecal grab samples of HNa + Gln group calves in comparison with the CON group (p < 0.05). In conclusion, combined administration of HNa and Gln effectively improved the growth performance, antioxidant and immune status, and intestinal beneficial bacteria, and further reduced the diarrhoea incidence of the pre-weaned calves.

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 humic acid and organic acids supplements on performance, meat quality, leukocyte count, and histopathological changes in spleen and liver of broiler chickens

The aim of the present study is to evaluate the effect of Humic Acid (HA), Organic Acids (OA), and their combination (HAOA) on the growth performance, meat quality, leukocyte count, and histopathological changes in the liver and spleen of broiler chickens. A total of 2100 one-day-old mix-sexed broiler chickens were randomly divided into 4 groups with 5 replicates per treatment using 105 birds per pen (pen is used as an experimental unit). Treatments were: 1) Control (basal diet without additives), 2) Basal diet +0.1% HA, 3) Basel diet +0.1% HA+ 0.02% OA, 4) Basel diet +0.02% OA. Growth performance was not significantly affected by all dietary treatments during the experiment period. Sensory evaluation of breast meat indicated a significant positive response for color and smell corresponding to treatment 2) Basal diet +0.1% HA and treatment 3) Basel diet +0.1% HA+ 0.02% OA (P < 0.05). Birds receiving HA and HAOA developed fewer hepatic lesions compared to the control group (P < 0.05) and showed normal spleen structure with the extension of the white pulp area. Supplementation of HAOA corresponds to a lower heterophil to lymphocyte (H/L) ratio. The combination of HA and OA improves sensory attributes of cooked breast meat, H/L ratio, and preserves the histological structure of the spleen and liver of broiler chickens. HAOA can be recommended as a combined feed additive to improve broiler chickens' health.

Ultrasound-Assisted Extraction of Humic Substances from Peat: Assessment of Process Efficiency and Products' Quality

Results of efficiency of obtaining humic substances (HSs) from peat in traditional alkaline extraction (TAE) and ultrasound-assisted alkaline extraction (UAAE) are presented. The influence of the duration of the process and ultrasound intensity on the efficiency of extraction of humic acids (HAs) and fulvic acids (FAs) extraction was determined. The composition of the fulvic acid fraction was examined depending on the type of eluent used. Fulvic acids were divided into fractions using columns packed with DAX-8 resin. For this process, 0.1 M NaOH and 0.5 M NH₃∙H₂O were used as eluents. For the quality assessment of specific fulvic acids fractions, spectroscopic methods (UV-Vis and FTIR) were used. Ultrasound had a positive effect on HS extraction efficiency, especially in increasing the amount of a desired hydrophobic fraction of fulvic acids (HPO). However, a negative effect of the excessive prolongation and ultrasound intensity (approximately 400 mW∙cm^-2) on the extraction efficiency of HPO eluted with 0.1 M NaOH solution was observed. Using peat as a raw carbon material for the HS extraction process can be used as an alternative industrial application of peat. UAAE may be considered as an alternative method to TAE, which provides a higher efficiency in HS isolation from peat.

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.

A Comprehensive Toxicological Assessment of Fulvic Acid

Fulvic acid (FA), a humic substance, has several nutraceutical properties, including anti-inflammation, antimicrobial, and immune regulation abilities. However, systematic safety assessment remains insufficient. In the present study, a battery of toxicological studies was conducted per internationally accepted standards to investigate the genotoxicity and repeated-dose oral toxicity of FA. Sprague-Dawley (SD) rats or ICR mice were used. Compared to the control group, there were no significant changes (all p > 0.05) in all FA treatment groups in the bacterial reverse mutation test, in vitro mammalian chromosome aberration test, in vivo sperm shape abnormality assay, and in vivo mouse micronucleus assay. The acute toxicity test showed that no mortality or toxic effect was observed following oral administration of the maximum dose of 5,000 mg/kg BW/day to mice or rats. A 60-day subchronic study was conducted at 0 (control), 200, 1,000, and 5,000 mg/kg/day. Compared to the control group, there were no significant changes (all p > 0.05) in the body weights, feed consumption, clinical signs, hematology, clinical chemistry, organ weights, or histopathology examinations. In conclusion, the no-observed-adverse-effect-level (NOAEL) of FA supplementation from the 60-day study was determined to be 5,000 mg/kg body weight/day, the highest dose tested. Our findings suggest that the oral administration of FA may have higher safety.

Effects of Dietary Supplementation of Humic Acid Sodium and Zinc Oxide on Growth Performance, Immune Status and Antioxidant Capacity of Weaned Piglets

Simple Summary

Weaning of piglets can destroy the piglet’s intestinal health and immune function, leading to diarrhea and a reduction in growth rate eventually. Considering drug resistance and residues, new alternatives, such as sodium humate (HNa), have attracted considerable research interest over recent decades. Our study was designed to explore the effect of HNa on the growth performance, diarrhea rate, antioxidative, inflammation, and immunity of weaned piglets and the possibility of HNa replacing antibiotics and zinc oxide. The obtained results indicate that HNa reduces stress, protects the intestinal barrier, and improves the performance of weaned piglets.

Abstract

At present, the widespread use of high-dose zinc oxide and antibiotics to prevent post-weaning diarrhea (PWD) in piglets has caused serious environmental problems. To solve this problem, we studied the effect of HNa as a substitute for zinc oxide (ZnO) and antibiotics on the growth performance, immune status, and antioxidant capacity of piglets. Seventy-two weaned piglets (body weight = 7.42 ± 0.85 kg, 26-d-old) were distributed in a randomized 2 × 3 factorial design (two sexes and three treatments) with six replicates of four piglets each. The three treatments were the control diet (basic diet), HNa diet (basic diet + 2000 mg/kg sodium humate), and ZoA group (basic diet + 1600 mg/kg zinc oxide + 1000 mg/kg oxytetracycline calcium). ANOVA and Chi-square tests were applied to compare the means (p < 0.05) between treatments. The results showed that body weight at 16 and 30 d and the average daily gain of piglets fed with HNa or ZoA were significantly higher (p < 0.05) than the control group. Supplementing HNa or ZoA significantly increased (p < 0.05) the level of immunoglobulin M and G, and reduced (p < 0.05) the concentration of inflammatory factors such as tumor necrosis factor-alpha (TNF-α), interleukins IL-6 and IL-1β, myeloperoxidase (MPO), and diamine oxidase (DAO). Furthermore, dietary HNa or ZnO significantly reduced (p < 0.05) the level of total antioxidant capacity (T-AOC) and malondialdehyde (MDA) compared with the control group. ZoA treatment showed an upward trend of IgA level and a downward trend of the concentration of lipopolysaccharide (LPS) and catalase (CAT). Overall, the study demonstrated that the addition of HNa in the diet partially replaced antibiotics and ZnO to improve the growth performance, immune function, and antioxidant capacity of weaned piglets, and maintained a good preventive effect on piglet diarrhea.

Dietary Supplementation of Inorganic, Organic, and Fatty Acids in Pig: A Review

Simple Summary

The role of acids in pig feed strategies has changed from feed acidifier and preservative to growth promoter and antibiotics substitute. Since the 2006 European banning of growth promoters in the livestock sector, several feed additives have been tested with the goal of identifying molecules with the greatest beneficial antimicrobial, growth-enhancing, or disease-preventing abilities. These properties have been identified among various acids, ranging from inexpensive inorganic acids to organic and fatty acids, and these have been widely used in pig production. Acids are mainly used during the weaning period, which is considered one of the most critical phases in pig farming, as well as during gestation, lactation, and fattening. Such supplementation generally yields improved growth performance and increased feed efficiency; these effects are the consequences of different modes of action acting on the microbiome composition, gut mucosa morphology, enzyme activity, and animal energy metabolism.

Abstract

Reduction of antibiotic use has been a hot topic of research over the past decades. The European ban on growth-promoter use has increased the use of feed additivities that can enhance animal growth performance and health status, particularly during critical and stressful phases of life. Pig farming is characterized by several stressful periods, such as the weaning phase, and studies have suggested that the proper use of feed additives during stress could prevent disease and enhance performance through modulation of the gastrointestinal tract mucosa and microbiome. The types of feed additive include acids, minerals, prebiotics, probiotics, yeast, nucleotides, and phytoproducts. This review focuses on commonly used acids, classified as inorganic, organic, and fatty acids, and their beneficial and potential effects, which are widely reported in the bibliography. Acids have long been used as feed acidifiers and preservatives, and were more recently introduced into feed formulated for young pigs with the goal of stabilizing the stomach pH to offset their reduced digestive capacity. In addition, some organic acids represent intermediary products of the tricarboxylic acid cycle (TCA), and thus could be considered an energy source. Moreover, antimicrobial properties have been exploited to modulate microbiota populations and reduce pathogenic bacteria. Given these potential benefits, organic acids are no longer seen as simple acidifiers, but rather as growth promoters and potential antibiotic substitutes owing to their beneficial action on the gastrointestinal tract (GIT).

Multiple factorial analysis of physicochemical and organoleptic properties of breast and thigh meat of broilers fed a diet supplemented with humic substances

Multiple factor analysis was used for the examination of meat quality of broilers, the diet of which was supplemented with 0.8 and 1.0% addition of humic substances (HS). One hundred fifty COBB 500 one-day-old male broilers chicks were randomly divided into 3 different groups: one control and 2 experimental (n = 50), and they were fattened for 35 D. Subsequently, the meat quality was analyzed and defined by physicochemical and sensory quality, supplemented with analysis by instrumental methods. We observed changes in dry matter, fat, water, and protein content in experimental samples of breast and thigh meat (P < 0.001). In both experimental groups, the concentration of phosphates and pH decreased in breast meat (P < 0.001) and in thigh meat (P < 0.05). The smell of experimental chicken breast meat samples after cooking was evaluated by a sensory panel, which scored a higher point score than that of the control group (P < 0.05). Sensory evaluation of taste indicated a positive response with respect to the perception of meat quality in relation to a greater supplementation of HS in the diet. Thigh meat samples showed a variable extent of water loss after cooking, but lower values of water loss were generally obtained from thigh meat samples of poultry fed with higher HS supplementation, than in chicken breast meat samples. Significant differences in evaluated variables between both experimental groups were not observed. The color of breast meat samples changed, when considering the variables of lightness and redness, with the addition of 1% HS (P < 0.05). The main advantage of the breast meat of broilers fed a diet supplemented with HS was observed in the final meat quality, which was positively affected by increased protein and decreased fat content. Because of its nutritional composition, it can be considered to be rather a valuable type of meat in human nutrition than ordinarily.

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

This study investigated the effects of dietary fulvic acid (FA) supplementation on the growth performance, body composition, oxidative status, and immunity of broilers. A total of 720 broilers were randomly divided into 4 groups, namely a control group and 3 treatment groups that received diets supplemented with 3 different levels of FAs (0.2, 0.6, and 1 g kg-1). The diets supplemented with 0.6 or 1 g kg-1 FAs increased the body weight gain. This treatment also increased the activities of digestive enzymes (amylase, lipase, and protease), the meat protein content, the total polyunsaturated fatty acid content, the superoxide dismutase activity, the glutathione peroxidise activity, and the serum levels of IgG, IgM, and IgA but decreased the meat fat content and the malondialdehyde level compared with those in the control. However, high FA dose (> 0.6 g kg-1) did not further increase the efficiency compared with moderate dose (0.6 g kg-1). Results indicate that FAs might be a promising dietary supplement for broilers.

Modulation of growth performance and nonspecific immunity of red swamp crayfish Procambarus clarkia upon dietary fulvic acid supplementation

An eight-week experiment was conducted to determine the effects of dietary fulvic acids (FAs) on the growth performance, digestive enzymes and nonspecific immunity of red swamp crayfish Procambarus clarkia. Three diets supplemented with three different levels of FAs (0.1, 0.5 and 1 g kg^-1) were formulated and tested for the growth performance, digestive enzymes and nonspecific immunity of the crayfish, and a diet without FAs served as control. After eight weeks of feeding, survival rate, phenoloxidase activity, superoxide dismutase activity, glutathione peroxidase level, total haemocyte count and number of hyaline cells, semigranular cells and granular cells and resistance to Aeromonas hydrophila of crayfishes fed with FA-containing diets were higher than those of the control. Moreover, based on the efficiency of FAs on the growth performance and nonspecific immunity of crayfish, the optimum dose of FAs was found to be 0.5 g (kg diet)^-1. A high level of FA administration (1 g kg^-1) did not further increase the efficiency of FAs compared with those in the moderate group (0.5 g kg^-1, p > 0.05). Results indicated that oral administration of FA-containing diets can enhance the growth performance, intestinal digestive enzymes, immune responses and resistance of crayfish to infection by A. hydrophila. Thus, FAs may be utilized as a diet supplement for crayfish.

Effects of dietary humic acid and enzymes on meat quality and fatty acid profiles of broiler chickens fed canola-based diets

Objective

This study was conducted to assess the effect of potassium humate and enzymes (Xylanase+Amylase+Protease) inclusion in diets on carcass characteristics, meat quality and fatty acid profiles of broilers fed canola-based diets.

Methods

Two hundred and twenty broilers randomly allotted to 5 dietary treatments: the control (commercial broiler diet); CM (17.5% canola meal inclusion); CMEnz (17.5% CM inclusion+0.3 g/kg Axtra XAP); CMPh (17.5% CM inclusion+1.5% Potassium Humate, PH); and CMEnzPh (17.5% CM inclusion+1.5% PH+0.3 g/kg Axtra XAP) were slaughtered at day 42 for assessment of carcass and meat quality parameters.

Results

Diet had no effect on carcass traits apart from breast muscle weight and breast muscle index. The highest breast muscle weight was observed in broilers fed CMEnz (487.6±17.5 g) followed by those fed the control diet (474.37±17.5 g). Diet also had no significant dietary effect on pH, temperature, drip loss and shear force values of the breast muscle. However, diet significantly affected meat colour and water-holding capacity. Broilers in the control and CMPh groups (52.94±0.67 and 52.91±0.67) had the highest (p<0.05) values for lightness (L*), whilst those fed CMEnzPh had the lowest value (47.94±0.67). In contrast, CM group had the lowest (p<0.05) value for redness (a*) with CMEnzPh group having the highest values. The proportion of polyunsaturated fatty acids (PUFAs), n-6 and n-3 fatty acids and the PUFA/saturated fatty acid ratio were increased in CM-based diets containing enzymes and humic acid.

Conclusion

It can, therefore, be concluded that CM can be included in broiler diets in the presence of enzymes and humic acid with positive effects on meat quality and important fatty acids that are beneficial to the health of consumers.

Effects of fulvic acids on goat sperm

The effects of adding fulvic acids (FAs) to semen extenders on the quality parameters of frozen–thawed goat buck spermatozoa remain undetermined. Buck semen samples collected from six mature goat bucks once a week were diluted with Tris–egg yolk-based extenders. The diluted semen samples were supplemented with FAs (0.2, 0.4 and 0.6%, w/w), cryopreserved, and evaluated for sperm-quality parameters. Addition of FAs to the extender increased progressive motility, acrosome integrity, membrane integrity, and superoxide dismutase and catalase activities and decreased percentage abnormality and sperm malondialdehyde level compared with the control group. However, excessive FA addition (>0.4%, w/w) to semen extenders did not improve the efficiency. The results indicated that FAs could be a promising cryoprotectant for goat buck sperm.

The effect of leonardite and lignite on the health of weaned piglets

A three-week trial was conducted to evaluate the effects of leonardite and lignite, natural sources of humic substances, on selected indicators of health status of weaned piglets. A total of 45 weaned piglets were assigned to three dietary treatments: Control - basal diet without any medication; Leonardite or Lignite - diet supplemented with lignite or leonardite at a dose of 20 g/kg, respectively. Leonardite differed from lignite in the content of humic substances and minerals. Diarrhoea incidence and severity, growth performance, haematological and biochemical status, biomarkers of oxidative stress, serum fatty acid (FA) profile and faecal microbiota composition were monitored. Significantly lower faecal score, diarrhoea incidence, serum biomarkers of oxidative stress, higher body weight gain and no mortality were observed in leonardite and lignite group. The supplemented groups had or tended to have higher haematocrit, haemoglobin, erythrocyte counts, iron, cholesterol and lower urea in blood. Increased serum minerals (calcium, phosphorus, magnesium) were detected in the leonardite group. Different effects of leonardite and lignite on serum FA profile were detected. Significantly lower proportion of saturated FA, higher unsaturated, monounsaturated, polyunsaturated (PUFA) n-3 FA and PUFA n6/n3 ratio were detected in leonardite group compared to lignite group. Both treatments decreased microbial diversity and richness of faecal microbiota at the genus level. Specifically, lower relative abundance of Firmicutes, Bacteroides, Anaerovibrio, Oscillospira, SMB53, Ruminococcus, and a tendency to a higher abundance of Prevotella was found compared to control group. Natural humic materials may provide benefit to piglets' heath in the difficult post-weaning period.

Effect of humates in diet of dairy cows on the raw milk main components

The effect of supplemental humic substances (HS) on the main milk components was investigated. A total of 10 dairy cows (Czech pied cattle, crossbred Czech pied cattle ´ Ayrshire and crossbred Czech pied cattle ´ Red Holstein) were tested. Animals were randomly divided into 2 groups, control (C) and experimental (E). Animals fed the same feed mixture and group E was additionally supplemented with HS (200 mg.kg-1 of product Humafit prepared from the Sakhalin Leonardite). The experimental period took 3 months. Cows were milked twice a day. The milk composition (lactose, fat, crude protein, pure protein and casein) of every cow was monitored on days 0, 14, 28, 42, 56, 70 and 84 of the experiment. Pure protein content was determined by Kjeldahl method, other components were analysed using an infrared analyserMilkoScan FT 120. It was found that the crude protein, pure protein and casein content in milk of group E significantly (p <0.05) increased from the 56th day of the experimental period. Differences of the protein fraction contents in group C and of the dry matter, non-fat dry matter, lactose and fat content in both groups were non-significant (p <0.05).Higher protein and especially casein content in milk could be very important for the cheesemaking as it could increase the cheese yield.

Effects of dietary supplementation of fulvic acid on lipid metabolism of finishing pigs

The experiment was conducted to investigate the effects of dietary supplementation of fulvic acid on lipid metabolism of finishing pigs. One hundred eighty crossbred barrows (Landrace × Yorkshire, 60 ± 2.5 kg) were randomly allotted to 5 dietary treatments (36 pigs/treatment) and fed a basal diet supplemented with 0, 0.2%, 0.4%, 0.6%, and 0.8% fulvic acid for 42 d. Thirty pigs (6 pigs/treatment) were slaughtered at the end of the experiment. Blood samples and adipose tissue were collected for determination of blood parameters and lipid metabolic enzymes. The results showed that compared with the control group, dietary supplementation of 0.2%, 0.4%, and 0.6% fulvic acid significantly reduced mean backfat thickness of pigs (P < 0.05). The serum concentrations of low-density lipoprotein, leptin, growth hormone, insulin, and triiodothyronine were significantly increased by adding fulvic acid in diets (P < 0.05). With the raised concentration of dietary fulvic acid, hormone sensitive lipase (HSL) activity was significantly increased (P < 0.05), and lipoprotein lipase (LPL) activity was significantly decreased (P < 0.05) in adipose tissue. In conclusion, dietary supplementation of fulvic acid reduced the mean backfat thickness of pigs. This change related to the increased activity of HSL and the decreased activity of LPL in adipose tissue.