Immunostimulants are substances capable of stimulating the immune system, increasing antibody production or increasing the activity of various immune cells.

It is also presented as an alternative to the antibiotics, to reduce the presence of bacterial resistance and the level of residues in products of animal origin.

Neonates ruminants depend on the intake of colostrum for passive immunity through immunoglobulins.

Therefore, there are two possible options to protect the infections. First colostrum can be used to substitute administering a larger amount of immunoglobulins or as second option can be used to increase immunostimulants to active immunity of the animal itself.

It has been studied using different types of immune-stimulating substances, including various drugs such as levamisole (intended as an anthelmintic), vitamins such as vitamin C and E, cytokines or based on extracts from plants rich with pronutrients among other products.

Interleukins (cytokines) have positive effects on early ages, acting as mediators between lymphoid, hematopoietic and inflammatory cells. For this reason the use of products containing pronutrients increase the production of cytokines.

Moreover, several studies documenting the use of plants with properties on the content of lactoferrin or somatic cells in cow or goat milk respectively, or the amount of lacto immunoglobulins in colostrum. These experiments obtained significant results in the increase of lactoferrin and immunoglobulin but no reduction of somatic cells in milk.

In other species, there have been studies that have evaluated the antibody titer after immunization, obtaining results superior to vaccination and observed an increase in immunoglobulin in blood after administration.

However, further study is needed to determine the effects of these products, both milk production as their possible application as subclinical disease preventives and avoid the use of antibiotics.