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Effect of fulvic and humic acids on performance, immune response and thyroid function in rats

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Effect of humic acid (HA) and fulvic acid (FA) on production parameters, immune response and thyroid function of rats were investigated in two experiments. First experiment: control or 0.1%, 0.2%, 0.4%, 0.8% HA- or FA-supplemented diets. Second experiment: control and 0.4% HA- or FA-supplemented diets. The feeding period lasted 26 days in both trials. No significant changes were observed in production parameters. Ovalbumine antibody titre of rats on HA- or FA-supplemented diets showed dose-dependent (at 0.4% supplementation) and significant (p < 0.05) increase (350 and 418% respectively) over the control (100%). Dose-related increase of plasma TSH (r = 0.99), and decrease of the T(4)/T(3) ratio (r = -0.97) was observed in FA-supplemented rats. Second experiment: both FA and HA stimulated the immune response by the 14th day (mean values: control: 685.79; FA: 1131.37; HA: 1055.6099) and 26th day (control: 544.31; FA: 1969.83; HA: 1600.00). No significant differences were noted with lymphocyte stimulation test. Diameter of the 'B'-dependent lymphoid tissues in the ileum and spleen were significantly (p < 0.05) larger in both the FA- and HA-treated animals. Humic acid and FA supplementation resulted in strong humoral immune stimulation. Our data also indicate that FA content is responsible for the mild hypothyroid effect of humic substances.
... HA is produced from the organic materials of dead plants and animal tissues by chemical and biological processes [3]. HA possesses various biology functions, including antioxidant, anti-inflammatory, immune-stimulatory, and antimicrobial properties, which have been used in agriculture, even as a supplementation used in human and animal clinical practices [4][5][6][7][8][9]. Studies indicated that the HA has been used as the neuron-or nephron-protective agents in clinical therapy based on the potential anti-inflammatory ability [10,11]. ...
... An earlier study demonstrated that HA exhibited the potent activity against human immunodeficiency virus that is not treated due to lack of the effective drugs [12], whereas, in veterinary medicine, HA may cure certain clinical symptoms including diarrhea, dyspepsia, and acute intoxication in horses, ruminants, swine, and poultry [3,6]. HA has also recently been used to increase the growth rate and improve feed efficiency and immunity, as well as improve the economic and ecological benefits during animal production [9,13]. ...
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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.
... Fulvic acid has a clinical beneficial effect in chronic inflammatory diseases and diabetes [39]. The full HSs fraction also has demonstrated anti-inflammatory activity [40][41][42]. ...
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(1) Background: Humic substances are well-known human nutritional supplement materials and they play an important performance-enhancing role as animal feed additives. For decades, ingredients of humic substances have been proven to carry potent antiviral effects against different viruses. (2) Methods: Here, the antiviral activity of a humic substance containing ascorbic acid, Se− and Zn2+ ions intended as a nutritional supplement material was investigated against SARS-CoV-2 virus B1.1.7 Variant of Concern (“Alpha Variant”) in a VeroE6 cell line. (3) Results: This combination has a significant in vitro antiviral effect at a very low concentration range of its intended active ingredients. (4) Conclusions: Even picomolar concentration ranges of humic substances, Vitamin C and Zn/Se ions in the given composition, were enough to achieve 50% viral replication inhibition in the applied SARS-CoV-2 virus inhibition test.
... The results of present study showed that NaH supplementation had no effects on the hematological indices and serum metabolites of pre-weaned calves. The immunomodulatory property of NaH was observed in rats and weaned piglets [28,29]. The concentration of serum immunoglobulin is an important indicator for immune function, which could protect the body against infections and inhibit inflammatory reactions [30]. ...
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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.
... 21 , experimentally induced herpes infection in the mouse ear was treated by applying a topical humic acid-derived substance, and it was concluded that the humic acid-derived agent significantly reduced or completely suppressed the infection. Vucskits et al. 22 In their study in rats, they stated that the humic acid diet both increases the immune response and prolongs the immune response time. Ji et al. 23 conducted a study on rats, and showed that humic acid accelerates the healing of wounds on the surface of the skin. ...
... On the first and 14th day of the experiment, the animals were immunised with 0.2 mL ovalbumin solution (50 mg ovalbumin þ 100 mL incomplete Freund's adjuvant (IFA) þ 100 mL PBS/rat) intraperitoneally. The antibody titres of the blood samples (collected on the 14th and 30th days of the experiment) were analysed using ELISA (Vucskits et al., 2010). ...
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