When it comes to fish feed, the ingredients have traditionally included fishmeal and fish oil. With new technology and environmental concerns, restrictions on the use of fishmeal and fish oil are being implemented and new research is discovering alternative ingredients for more sustainable sources of nutrients to support the aquaculture industry. There are about 40 essential nutrients that are necessary for fish health that both fishmeal and fish oil contain, which is why those two ingredients have been used so frequently.

Necessary Nutrients

For fish to thrive, there are essential nutrients that need to be included in their diet in varying amounts depending on species. Proteins, carbohydrates, and lipids are the three main categories these nutrients fall under. The ratio of proteins to carbohydrates to lipids changes depending on fish species, age, size, and whether it’s a carnivore, herbivore, or omnivore.

Proteins

Proteins are composed of various combinations of amino acids. There are “essential” amino acids, which must be provided through the diet, and “dispensable” amino acids that the fish can absorb or synthesize from sources other than their diet. There are about ten known essential and dispensable amino acids that are necessary for fish health.

Essential Amino Acids

• Arginine
• Histidine
• Isoleucine
• Leucine
• Lysine
• Methionine
• Phenylalanine
• Threonine
• Tryptophan
• Valine

Dispensable Amino Acids

• Alanine
• Asparagine
• Aspartic Acid
• Cystine
• Glutamic Acid
• Glutamine
• Glycine
• Proline
• Serine
• Tyrosine

Lipids

Lipids are compounds of fat and oils that can vary greatly in composition and nutrient amounts. They provide a concentrated source of energy for fish.

Carbohydrates

Carbohydrates are not technically required in fish diets, but they are a cheap source of energy. Carnivores tend to use this energy source less efficiently than herbivores or omnivores.

There is another group of nutrients, known as “micronutrients”, that consists of various minerals and vitamins that the body needs for many standard functions.

Alternatives to Fishmeal and Fish Oil

The National Oceanic and Atmospheric Administration (NOAA) conducted several studies and published their research on alternative fish feed solutions. The research confirmed that fishmeal and fish oil are not necessary for healthy fish diets, even though they are a quick, reliable source of the 40 essential nutrients. The main difficulty in creating alternative fish feeds is understanding the exact dietary needs and preferences of different species.

One of the reasons that fishmeal and fish oil are so reliable is they contain almost the perfect balance of those 40 nutrients and are easily digested by all fish which will have to be replicated in alternative feed solutions.

The most common alternative feed sources are plants such as soy, wheat, and corn, insects as protein sources, algae, and even recycled human food waste. The amount of fishmeal and fish oil used in aquaculture has already decreased significantly over the last 40 years and is still on the decline.

According to the NOAA, “…it is estimated that the amount of fishmeals in salmon diets has dropped from being 70% of the diet in 1980, to about 25% in 2017”. The amount of current research products and innovative feed production methods is promising for the future of aquaculture and our planet as the demand for fish continues to rise.

Support Global Food Security by Giving Your Farm a Breath of Fresh Air

Alongside a healthy and well-balanced diet, fish need a healthy, well-balanced environment to thrive in. Give your farm a breath of fresh air and improve your water quality management today by contacting Aquasend® to learn about our real-time monitoring system.