Various research studies of probiotics have demonstrated important but limited health maintenance merits through their ability to provide beneficial microorganisms and support. These foster healthy homeostatic balance to the natural microflora of the digestive system. The benefits of prebiotics are limited to the support and development of microflora. However, both probiotics and prebiotics have shown no proven effects on the immune system of animals, nor astringent effects on the mucous membrane of the gastro-intestinal tract. They also have failed to reveal antibacterial, virucidal or antitoxic effects against pathogens. Various performance studies have shown that probiotics and prebiotics have no substantial effects on animal growth.

Plant extracts are believed to be beneficial for the digestive system, but in this regard their functioning mechanism is not completely known and should be different for each product in this category. Organic acids’ value as protective agents is part of their being growth promoters.

Due to variations inherent to all natural mineral deposits and variables in individual applications that are not under our control, no product claims can be made or inferred by the manufacturer. However, studies and trials of naturally formed and non-chemically derived ancient humic acids of related composition generally suggest the following applied categories, attributes and capabilities:

 

Humic Acids as an Animal Feed Ingredient

The use of humic acids in animal feed produces a number of encouraging advantages for animal health and growth, discovered during scientific research and born out in livestock studies.

Humic acids show a marked tendency to inhibit pathogenic bacterial growth and growth of molds and thus may decrease levels of mycotoxins. They have the capacity substantially to improve protein digestion and calcium and trace element utilization. Humic acids tend to improve intestinal health, nutrient absorption, nutritional status and immune response in animals. Humic acids are now known to improve diet digestibility as a result of the maintaining of optimum pH within the intestines which result in lower levels of nitrogen excretion and less odor. Humic acids not only improve digestibility and more complete food utilization, they also improve gastric and intestinal conditions of animals.

It follows from this that, as well as the direct improvement of physical productivity, performance, health and in turn, financial profitability, because humic acids exert an indirect positive impact on the environment. This is due to healthier residual feed decomposition and improved fertilizer properties of livestock fecal matter with reduced pathogens.

The replacing of antibiotics with humic acids as growth promoters in animal feed does not cause any loss in the performance of animals. On the contrary, performance factors (daily live weight gain, feed intake, food conversion ratio and the level of looseness of feces-scour assessment) of animals are considerably improved. Tests have shown that the use of humic acids as animal feed supplement leads to increased milk production and increased butterfat percentage in dairy cows. The use of humic acids also resulted in improved feed efficiency, decreased feed costs, reduced fly population and reduced costs for insect control. Furthermore, the weaning weights increased and faster weight gains were observed in dairy cows while problems with scours greatly decreased.

On the whole, humic acids increase animals’ resistance against stress factors such as heat.

One of the most beneficial effects of humic acids on animals is the overall immune response increase in animals. Because humic acids improve immune functions in animals, they are able substantially to reduce the incidence of diarrhea and other digestive upsets as well as to improve animals’ defenses against pathogens such as E.coli.

 

Observed Effects of Humic Acids on Animals

Covering mucous membrane and astringent effects	Humic acids are able to form a protective film on the mucous epithelium of the gastro-intestinal tract against infections and toxins. The macro-colloidal structure of humic acids ensures a good shielding of the mucous membrane of the stomach and intestines, the peripheral capillaries and damaged mucous cells. This process reduces or fully prevents the resorption of toxic metabolites after infections in case of residues of harmful substances in animal feed or when it is switched to new feeds. Furthermore, humic acids also help to prevent excessive loss of water through the intestine.
Antibacterial and virucidal effects	Humic acids have the ability specifically to influence microbial metabolism of proteins and carbohydrates by catalytic means. This leads to a direct devastating effect against bacteria or viruses. A second mechanism is related to the inter-ionic bonds of high-molecular protein fractions (toxins) of infectious microbes. Their toxic impact on physiological processes of mucous membrane cells can be weakened considerably or even blocked completely.
Antiphlogistic effects	Dermal, oral or subcutaneous application of humic acids lead to inhibitory effects on inflammation. The ability to inhibit inflammation is believed to be related to the flavonoid groups contained in humic acids.
Antiresorptive and absorptive effects	As high-molecular humic acids remain in the gastro-intestinal tract almost entirely following the enteral application (there is no self-resorption), antiresorptive and absorptive effects take place where they are needed: in the digestive tract. Primarily cationoid noxes (protein toxins, toxic substances) are fixed, their resorption is reduced considerably or even prevented completely and their elimination through feces is promoted. Because adsorption by humic acids includes not only physical and chemical reactions but also complex-formation and ion-exchange, it is more intensive and dynamic compared to pure physical adsorbents.
Effects on the immune system	Humic acids stimulate the resistance forces of the body and lead to the increase in the phagocytosis activity. The inducer effect of phenolic components (groups) of humic acids is believed to be responsible for the immunological effects and is the basis for the success of the treatment of the so-called factor diseases in young animals.
Ergotropic effects	Humic acids stabilize the intestinal flora and thus ensure the improved utilization of nutrients in animal feed (improved feed efficiency). This leads to an increase in live weight of an animal without increasing the amount of feed given to animals.

 

Humic acids are purely natural. The use of humic acids in animal feed excludes any possibility of antibiotic residue or microbial resistance. Simultaneously, as a result of a higher food conversion rate and enhanced absorption of nitrogen by animals, nitrogenous wastes and odor are reduced.

 

The Role of Humic Acids

Humic acids are colloids and they behave somewhat as clays even though the nomenclature suggests that they are acids and form true salts. When the cation exchange sites on the humic molecule are filled predominantly with hydrogen ions, the material is considered to be an acid and is named accordingly. However, it has no great effect on pH because the acid is insoluble in water. When the predominant cation on the exchange sites is other then hydrogen, the material is called humate. The humates of monovalent alkaline metals are soluble in water, but the humates of multivalent metals are insoluble. Apart from their effect on the solubility of the materials and their absorption by clays, the different cations have little effect on the humic molecules. The manifold effect of humic substances on plants, shown both in the external medium and in the biochemical processes that occur in plants, has been well demonstrated.

 

There is a growing interest in the use of organic materials such as fertilizers or soil amendments. This may be attributed to: 1) an interest in the reduction of the use of chemical fertilizers; 2) public concern for the potential polluting effects of chemicals in the environment; or 3) a pressing need for energy conservation. The research reported herein was conducted in an effort to explore humate material as one of the organic natural resources with the potential to meet some of these needs.

Reference: Senn, T. L. and Alta R. Kingman, 1973, A review of Humus and Humic Acids. Research Series No. 145, S. C. Agricultural Experiment Station, Clemson, South Carolina.

 

This study showed significant increases in yield on potatoes, soybeans and algae cultures on test plots near Grand Forks, North Dakota. Other tests in North Dakota documented yield increases in barley with or without applied mineral fertilizer (Agvise Inc., 1977-1979). Tests done by commercial farms have consistently resulted in a significant reduction in irrigation water usage on plots treated with humates, as well as better seed germination, leaf petiole growth and crop yields. Interest in humates and their value in agriculture is increasing rapidly. There are numerous universities and commercial concerns engaged in test and documentation of the benefits of humates used in fertilizers, animal feed and environmental remediation.

About Humic Substances

Humic substances are ubiquitous in the environment. Their importance in agriculture and soil sciences has been acknowledged for over 150 years. Aquatic scientists have been slower to appreciate their importance, but now realize that they may constitute as much as 95% of the total dissolved organic matter in aquatic systems and often are equal to or greater than the concentrations of inorganic ions present. In many cases they act as the major buffering system which has serious implications for acidification of lakes and rivers.

 

 

 

 

While important for microbial processes that drive many ecosystems in our world, the true interest in the study of chemistry are their interactions with other elements and compounds. Humic substances have been documented to interact in some manner with over 50 elements from the periodic table.

SEM image (approx 2000x) of a solid humic acid Click here to see in greater detail

These include nutrients, toxic metals, radio-nuclides (including the trans-uranium series) and the halogens. The latter can interact with humic substances in drinking water treatment to produce halogenated carcinogens such as chloroform and bromoform which are then directly introduced into the public drinking water with obvious health consequences. Toxic metals and micronutrients can be made either more available to organisms or actually sequestered in order to reduce their toxicity or beneficial value. Furthermore, humic substances contain long-lived (almost stable populations) of free radicals which are capable of reducing inorganic species such as mercury and chromium. They are also able to interact with anthropogenic organic compounds such as polycyclic aromatic hydrocarbons which include the known carcinogen benzo-pyrene, again to alter the chemical reactivity of these important chemicals.

The mechanisms of many of these interactions are unclear. That is a result of our lack of knowledge of the structural components of humic substances. While it is true that we understand certain gross structural characteristics, i.e. many toxic metals are believed to be complexed through carboxyl groups and because copper appears to be bound through some unidentified nitrogen moities and the stabilization of free radicals appears to involve quinone/semi-quinone structures, we have no structural knowledge that allows us to predict the extent of these reactions under given physico-chemical regimes. Furthermore, without structural knowledge, measurement and prediction of the kinetics of reactions are impossible.

A further riddle concerns the nature of organic compounds that are produced by biological and geochemical processes that contain structures which can complex metals, sequester anthropogenic organic compounds, oxidize and reduce elements to and from toxic forms, photosensitize chemical reactions and enhance or retard the uptake of toxic compounds or micronutrients to plant and microbial organisms. Without structural knowledge of humic substances, we will continue to rattle around in the black box of ignorance when asked to predict and forecast the impacts of chemical and biological actions on our environment. Those of us who have studied these compounds know their importance to chemical (another facet of humic substances is their interference in industrial processes such as aluminum processing), agricultural, environmental and even health issues (humic substances are widely used in the treatment of many animal maladies and their use in human health).

While the study and eventual elucidation of the structure of these complex mixtures might at first glance seem esoteric, they are important components in processes that touch an extremely broad suite of scientific disciplines.

 

 

Further Suggested Reading

G. R. Aiken, P. MacCarthy, R. L. Malcolm and R. S. Swift, 'Humic Substances in Soil, Sediment, and Water', Wiley, New York, 1985.

M. H. B. Hayes, P. MacCarthy, R. L. Malcolm and R. S. Swift, ‘Humic Substances II: In Search for structure’, Wiley, Chichester, 1989.

P. MacCarthy, C. E. Clapp, R. L. Malcolm and R. R. Bloom, ‘Humic Substances in Soil and Crop Sciences: Selected Readings’, American Society of Agronomy, Madison, Wisconsin, 1990.

W. Ziechmann, ‘Humic Substances’, BI Wissenschaftsverlag, Mannheim, 1993.

N. Senesi and T. M. Miano, ‘Humic Substances in the Global Environment: Implications for Human Health’, Elsevier, Amsterdam, 1994.F. J. Stevenson, 'Humus Chemistry: Genesis, Composition, Reactions', 2nd edn., Wiley, New York, 1994.

J. S. Gaffney, N. A. Marley and S. B. Clark, ‘Humic and Fulvic Acids: Isolation, Structure and Environmental Role’, American Chemical Society Symposium Series 651, 1996.

M. H. B. Hayes and W. S. Wilson 'Humic Substances, Peats and Sludges: Health and Environmental Aspects', Royal Society of Chemistry, Cambridge, 1997.

G. Davies and E. A. Ghabbour , ‘Humic Substances: Structures, Properties and        Uses’, Royal Society of Chemistry, Cambridge, 1998.