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

A. V. Vucskits, I. Hullár, A. Bersényi, E. Andrásofszky, M. Kulcsár, J. Szabó

Research output: Article

30 Citations (Scopus)


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 T4/T3 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.

Original languageEnglish
Pages (from-to)721-728
Number of pages8
JournalJournal of Animal Physiology and Animal Nutrition
Issue number6
Publication statusPublished - dec. 1 2010


ASJC Scopus subject areas

  • Food Animals
  • Animal Science and Zoology

Cite this