Date: 03/03/2026

Tilapia feeding is a determining factor in productive performance throughout the production cycle. Indicators such as growth, feed conversion, batch uniformity and cost per kilogram produced are directly linked to the quality and balance of the diet provided. For this reason, nutritional formulation requires a detailed understanding of how nutrients are utilized by the fish and the need for specific adjustments at different stages.

In addition to protein level, it is necessary to consider digestibility, amino acid profile, available energy and feed acceptance. Small imbalances can compromise nutrient utilization and reduce production efficiency. On the other hand, well-planned adjustments contribute to improved feed conversion, minimize waste and increase economic predictability.

In this article, you will find:

What are the nutritional requirements of tilapia?

For fish weighing over 100 g, the estimated requirement for de digestible protein is approximately 24.3% of the total diet composition. This highlights the importance of formulations based on digestible nutrients rather than solely on crude protein.

Beyond protein level, the balance of essential amino acids is critical to support nutrition. Lysine, methionine, threonine and tryptophan are often limiting. When one of them falls below optimal levels, protein synthesis is reduced even if total protein content appears adequate.

How does science evaluate new ingredients in tilapia diets?

When researchers test a new ingredient (such as a protein hydrolysate), they do not change the entire feed formulation. Instead, protein and energy levels are kept constant, and only the component being evaluated is modified. This type of formulation is referred to as isoproteic and isoenergetic.

In practice, all experimental diets contain the same crude protein level and the same energy value. Therefore, any differences observed in intake, growth or feed conversion can be attributed to the ingredient being tested rather than to a nutritional imbalance.

What do studies show about hydrolysates?

In the study published in Research, Society and Development (Cruz et al., 2022), which evaluated the inclusion of swine mucosa hydrolysate as a feed stimulant for juvenile tilapia, diets were formulated with 40% crude protein and 3,250 kcal/kg of energy.

Although hydrolysate inclusion levels ranged from 0% to 5%, researchers adjusted proportions of ingredients such as soybean meal, tilapia meal, oil and synthetic amino acids to maintain nutritional balance. Thus, when the 1% inclusion level resulted in higher pellet intake, the outcome was attributed to the hydrolysate’s effect on palatability rather than to an increase in dietary protein or energy.

In the study published in Aquaculture Research, which evaluated liquid hydrolysates derived from swine and poultry, diets were also formulated based on nutritional recommendations for juvenile tilapia. The only variable factor was the ingredient included (5% of each tested source), allowing specific evaluation of its effects on attractiveness and feed intake.

For producers or formulators, it is not sufficient to include a new ingredient and observe the result. It is essential to ensure that digestible protein, essential amino acids and energy remain balanced. If the inclusion of a component alters this balance, performance may change due to basic nutritional factors rather than the functional effect of the ingredient.

In tilapia farming, dietary decisions directly impact growth, feed conversion and cost per kilogram produced. Therefore, understanding how studies are conducted helps ensure accurate interpretation of results and supports technically sound and safe application in the field.

What is the impact of digestibility on tilapia feed conversion?

Apparent protein digestibility (ADC) varies depending on the raw material used. In trials with swine-derived protein hydrolysates, crude protein digestibility coefficients ranged from 95.7% to 98.3%. High values were also observed for essential amino acids, indicating high metabolic availability.

In practical terms, higher digestibility means:

● Improved utilization of ingested amino acids
● Lower nitrogen excretion into the water
● Reduced feed conversion ratio when intake is adequate

In an experiment with fingerlings fed hydrolyzed chicken protein (0% to 6% inclusion), feed conversion decreased from 1.79 in the control group to 1.09 with 2% inclusion. This result corresponds to an approximate 39% reduction in the feed-to-weight gain ratio.

The best results were obtained with 2% to 3% inclusion. Above this range, gains were no longer proportional. This information is relevant for practical formulation: successive increases in dosage do not guarantee continuous improvement.

Palatability and feed intake in tilapia

Productive performance depends on effective diet intake. In palatability tests, two diets containing 5% inclusion were compared: one with dried chicken protein hydrolysate and the other with fish meal. The hydrolysate treatment showed a higher palatability index and greater pellet intake.

On the other hand, trials with liquid hydrolysates at 5% inclusion did not demonstrate superiority over fish meal and, in some cases, resulted in lower intake.

These results indicate that:

● The peptide and free amino acid profile of the ingredient influences acceptance
● The physical form of the ingredient (dry or liquid) may alter the response
● Moderate inclusion levels tend to be more efficient than higher inclusion levels

It is important to emphasize that dosage must be adjusted according to the objective.

How does tilapia feeding vary by production phase?

Tilapia feeding varies throughout the production cycle, as nutritional requirements change according to body weight, growth rate and physiological stage. Dividing feeding management into phases is a technique that allows more precise adjustment of digestible protein, energy and amino acid levels.

Initial phase (post-larvae and fingerlings)

● Higher relative requirement for digestible protein
● High sensitivity to raw material quality
● Strong impact of palatability on intake
● Direct influence on batch uniformity and survival rate

At this stage, inclusion of hydrolysates at moderate levels (around 2% to 3%, according to studies) showed the best response in terms of feed conversion.

Growth and fattening phase

● Focus on cost per kilogram of gain
● Precise adjustment of essential amino acids
● Balance between energy and protein to prevent excessive fat deposition

In fish weighing over 100 g, maintaining adequate digestible protein and a proper amino acid profile becomes more relevant than simply increasing crude protein levels.

Performance indicators in tilapia production

To assess the success of a feeding strategy, it is necessary to look beyond final fish weight. Growth is important, but it is not sufficient to measure productive performance. In tilapia farming, performance analysis involves a set of indicators that help determine whether the diet is effectively converting nutrients into biomass gain in an efficient and sustainable manner. The main indicators should include:

● Apparent feed conversion ratio (FCR)
● Specific growth rate
● Survival rate
● Batch uniformity
● Water quality
● Hepatic and intestinal evaluation in case of formulation changes

By monitoring these indicators, it is possible to observe that tilapia feeding performance is directly related to the nutritional quality of the ingredients used. Raw materials with high digestibility promote improved amino acid utilization and contribute to more efficient feed conversion, directly impacting productive performance.

The relationship between diet and tilapia performance begins with ingredient quality. Learn how the BioActio line from MBRF Ingredients can contribute to more efficient formulations.