Tilapia, like all other fish, have an immune system that includes mechanical barriers, non-specific and specific cellular and humoral defence systems.

Due to evolution, as in mammals, fish rely more on the immunospecific response than on the non-specific one. Specific mechanisms require antigen induction, antigen specificity and immunological memory.

Vaccination is an essential method to optimize the functioning of the specific immune system of tilapia during their productive cycle, however, several risks can lead to serious vaccine failures.

Immunostimulant pronutrients are an innovative therapeutic alternative that can improve the action of vaccination and even enhance the functionality of the immune system when animals are not vaccinated.

Results achieved with the use of immunostimulant pronutrients in tilapia

Recently, a trial was conducted in 16-week-old tilapias to evaluate the effect of immunostimulant pronutrients. A total of 648 animals were distributed in 12 tanks of 25 L each and were divided into four treatments (T1 control group and T2, T3, and T4 groups supplemented with immunostimulant pronutrients) and fed with standard basal diet. The T2, T3, and T4 groups received a supplementation at a dose of 2ml/kg, 4 ml/kg, and 6 ml/kg, respectively.

The objective of the trial was to evaluate the effect of immunostimulant pronutrients on parameters such as weight gain, feed conversion and growth rate.

The results were the following:

Groups T2, T3, and T4 show an increase of 96.51%, 61.24% and 70.54% compared to the control group T1.

The T2, T3, and T4 groups improved feed conversion ratio by 16.7%, 31% and 21.2% compared to the control group.

In terms of immunological and nutritional status, the results were the following:

In aquaculture, the white blood cell count is an indicator of immune function. A low white blood cell count can lead to reduced resistance to infections.

Immunostimulant pronutrients increased the percentage of white blood cells in the trial, indicating increased resistance to possible infections.

A low haematocyte count may be due to nutritional and welfare problems. Immunostimulant pronutrients increased the haematocrit value, the marker of improved nutritional status and well-being.

Conclusions

In aquaculture, several stressors can alter the immune capacity of fish. These stressors make them more prone to become clinically ill and worsen their productive performance. Immunostimulant pronutrients, thanks to the stimulation of the immune system of tilapia, achieve a better nutritional and defensive status, which translates into an indirect improvement of production parameters.

Immunostimulant prononutrients have been developed by Biovet S.A. and are marketed under the name Alquernat Immuplus.