No compromise: between quality and profitability in aquaculture

The encouraging route to safeguarding profit margins  

Protein represents a significant expense in feed formulations, necessitating careful management. The effective use of this nutrient, along with its quantitative and qualitative aspects, is vital for sustainable production and financial efficiency. A viable strategy involves managing feed efficiency and expenses through the use of feed enzymes to:  

• increase the nutritional benefits of feed and its components  
• boost growth performance  
• and optimize overall feed expenses.

Understanding the impact of feed performance 

The quality and composition of raw materials in aqua feed can greatly affect the performance of aquaculture species:

1. Nutrient content and variability

Plant and animal feed raw materials can exhibit variability in nutrient quality due to environmental factors, different processing conditions, contamination, transportation, and storage. High quality raw materials should have a good and balanced nutrient and energy content that promotes growth, health, immunity, and productivity and have a consistent quality that meets the raw material specifications.

2. Digestibility

Based on the apparent digestibility coefficients of conventional ingredients, the digestibility of amino acids from animal protein is between 80and 90 %, while many raw materials from animal by-products are between 65% and 75 %. This value can vary considerably depending on the type, species, quality, and origin of the ingredient. Ingredients with a higher digestibility ensure that the nutrient is efficiently utilized and nutrient loading in the environment is reduced while improving feed conversion ratio (FCR).

3. Anti-nutritional factors

The increasing use of plant-based protein in aquafeeds for sustainability and cost reasons is often accompanied by antinutritional factors that hinder nutrient uptake and form complexes (mineral-phytate complexes, amino acid–phytate complexes and protein–phytate complexes) that reduce nutrient availability. 

Optimizing phosphorus utilization

Phosphorus (P) is crucial for aquatic animals, especially as fishmeal is replaced with plant-based ingredients. To prevent phosphorus deficiency, supplementation is common, but adding inorganic phosphates is costly and less efficient than improving the digestibility of phytate-bound phosphorus already present in feed.

Plant-based ingredients in aqua feeds contain phytic acid, an anti-nutritional factor that hinders performance. This form of phosphorus, making up over 60% of total P in many plant ingredients, is indigestible and often released as waste.

Phytase enzymes break down phytate, freeing inorganic phosphorus and reducing the need for costly supplements. This improves phosphorus availability and boosts nutrient absorption.

Maximizes protein utilization 

Amino acids form the chain structure of proteins. The use of proteases cleaves the peptide bonds that connect the amino acids, the building blocks of proteins. Without proteases, these bonds cannot be easily broken, and the proteins cannot be easily digested by fish and shrimp. 

The addition of proteases improves the digestibility and absorption of proteins by releasing the nutritional value of feed proteins by supporting the degradation activities of digestive enzymes such as pepsin, chrymotrypsin and proteases. This results in more nutritionally available peptides and free amino acids.

Unlocking plant protein and fiber efficiency

Modern feed ingredients often contain complex carbohydrates that bind or encapsulate proteins, especially in plant-based materials where nutrients are stored within plant cells. Utilizing new plant-based ingredients requires strategies that improve flexibility in ingredient use and fiber management.

In aquatic animals, particularly juveniles and carnivorous species, the lack of sufficient endogenous carbohydrases hinders the breakdown of complex cell walls, limiting nutrient absorption, growth, and health.

Importance of Fiber Management:

• Dietary fiber: Found in feed, primarily as non-starch polysaccharides (NSPs) in cereals and oilseeds.
• NSPs: Resistant to digestion in monogastric animals, acting as anti-nutritional factors.

Role of fiber-degrading enzymes:

• Break down insoluble NSPs, releasing trapped nutrients like starch and proteins.
• Break down soluble NSPs, reducing viscosity to enhance nutrient absorption and feed intake.
• Support oligomer production with potential prebiotic effects.

The use of carbohydrases such as cellulase, xylanase, glucanase, pectinase or multienzyme carbohydrase is a versatile tool to improve the breakdown and utilization of these complex materials, increasing the value of raw materials through direct cost savings while contributing to a more sustainable feed industry with less nitrogenous waste products.

Flexibility in raw material use

Enzymes allow the use of a borader range of feedstuffs, including non-conventional sources or alternative raw materials, and thus offer flexibility in the formulation of feeds. A very good example of this is the increasing use of indigenous raw materials with high fiber content. Some trending raw materials such as Distiller Dried Grains Soluble (DDGS), which are more economical, need to be handled differently as these raw materials carry the risk of mycotoxins and the use of mycotoxin risk management additives and multi-enzymes such as protease and xylanase helps the degradation of proteins, making them more available to the animals.

Least cost formulation

The Least Cost Formulation is achieved by continuously adjusting the feed formulation based on the price and nutritional content of available raw materials to maintain feed quality and performance. 

Combining different feed ingredients in a ratio that meets the nutritional needs of the species at the lowest possible cost is a daily challenge but is feasible. One option is to use the enzyme nutritional matrix to replace more expensive mineral, amino acid and energy sources.

What’s Next?

Enzyme is one of a well-recognized tools to balance cost of production and performance. It allows the use of a broader range of feedstuffs, including non-conventional sources or alternative raw materials, offering flexibility in diet formulation economic benefits. Incorporating enzyme matrix values into the feed formulation support cost optimization by replacing more expensive ingredient and release more nutrient from the current raw materials. 

The use of enzyme combinations can alleviate pressure on feed costs and provide significant nutrient release, which is often overlooked, without compromising animal performance and contributing to economic efficiency.