The overarching long-term goal from a food-feed standpoint is to push algae into the spotlight as a sustainable, alternative protein to help feed a burgeoning population with limited resources. But this aquatic organism is so much more than protein; it is rich in fatty acids, carbohydrates, beta-glucans and other bioactive compounds that all hold significant promise in preventative animal health.
“We know a lot, but not everything — and we certainly need to know more,” says Ian Jameson, director of the Australian National Algae Culture Collection (ANACC), part of the country's national science research agency CSIRO. “There are gaps in our biological knowledge and the optimization of production and harvesting technologies.”
For example, there could be more than 1 million algae species, and there is also great genetic diversity within each species.
While ANACC focuses most of its research on taxonomy, biogeographic diversity and climate impact on algae, he says wider efforts largely focus on algae's protein and essential lipid production.
'Extra value' unique to algae
Xingen Lei, professor of animal science at Cornell University's College of Agriculture and Life Sciences, says algae as a new protein source is hugely exciting.
“I'm always trying to convince my colleagues in the engineering field that microalgae has more potential as a protein than as an energy resource,” he says. The argument for this is even stronger when considering marine microalgae that doesn't require fresh water – an increasingly limited resource – or byproduct microalgae, he says.
Lei's team has extensively researched the protein potential of defatted microalgae, a byproduct of biofuel production, and findings place final protein content anywhere between 14 to 43 percent, putting the highest concentration on a par with soybean meal.
However, to become a viable protein alternative, he says industry must “find an extra value” that is “unique to microalgae” to position it as a dual-benefit ingredient. Omega-3 could be a strong contender, he says.
Lei says even defatted microalgae, with minimal amounts of fat, can enhance the omega-3 content in final chicken meat or egg products, specifically docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) levels.
“It's not only about replacing amino acid or protein from the soybean but also bringing extra nutrients or active compounds into the diet to benefit the animal as well as the animal products for human consumption,” Lei says. “If we can make that work, producing a value-added product, we can mark a higher price and justify the cost for this new ingredient into the animal diet.”
David Suárez, head of production at Neoalgae, says the environmental context of microalgae should also be a draw.
“One of the greatest advantages of microalgae is they do not need land to be grown,” says Suárez. Microalgae can be derived from cultures and can reach high yields quickly while absorbing CO2.
He says for poultry and livestock, the biggest opportunity is in active compounds extracts for supplementation. Neoalgae uses a supercritical fluid extraction (SFE) technique, for example, to obtain high-quality omega-3 fatty acids from marine or freshwater microalgae species.
Can algae find its place in animal feed nutrition? (MilenaKatzer | istock.com)
Algae's many positive effects
Marinus van Krimpen, senior researcher for animal nutrition at Wageningen UR Livestock Research, believes that, as a simple protein, it may take decades before algae is considered important in animal diets — 10 to 20 years, at least — because it's just too costly compared to soybean.
He agrees, however, that algae's immediate potential can be found in its other nutritional compounds, like beta-glucan, that can replace organic acids, probiotics or prebiotics for improved gut function in young or vulnerable animals.
The microalgae chlorella, for example, contains 2.9 grams of beta-glucan per kilogram, and some seaweed species contain up to 6.7 grams per kilo — values “really high compared to common products,” he says.
Van Krimpen's latest in vitro research using cells from young pigs indicates “many positive effects” beta-glucan rich algae can have in the gut, from activating the immune system to preventing over-expression of inflammatory cytokines. These health-promoting aspects of algae, he says, are “really promising” and something his team hopes to further prove through an in vivo study feeding chlorella powder to broilers and measuring gut integrity and gene expression in the gut cells. The team will also conduct a similar trial in piglets this year, testing various seaweed and microalgae species.
“If we can show the mode of action (MoA) of these products, then they will definitely be applied for a feed additive between now and five years time, I expect,” he says.
Kemin Industries' Aleta product, made from fermented Euglena Gracilis microalgae containing more than 50 percent beta-glucan, is already positioned as a feed additive for immunity support, improved vaccination efficiency and antibiotic reduction support. Initially developed by U.S. startup Algal Scientific, Kemin acquired the technology and staff two years ago. The microalgae can be harvested every 24 hours and repopulates every day with minimal input.
Jennifer DuCray, product manager for Aleta at Kemin, says the highly bioavailable product can be used across all species.
“Beta-glucans are extremely beneficial to prime the immune system and help the animal, especially young livestock or those being raised without antibiotics,” DuCray says.
The product's MoA is already “well established” and proven in rats, she says, and the company is now focused on field demonstrations.
Tom Marstellar, DVM, senior technical service manager at Kemin, says the company will conduct a supplementation trial in a commercial swine herd of more than 1,000 with a diarrhea situation, and build up data on cattle, particularly young calves.
Algae's true potential lies in its array of nutritional compounds. (greenleaf123 | iStock.com)
Pi Nyavll Collén, scientific director at Olmix Group, says macroalgae or seaweed can also play an important role in animal immunity thanks to its year-round carbohydrate density. Working with wild-harvested green and red seaweeds, Olmix extracts biologically active polysaccharides that she says can be used to regulate the immune system in poultry, livestock and aqua animals and even improve immunity in young and vulnerable-stage animals
“What we can see is there's an immune regulation,” Collén says. “Basically, when we test the products, we can see they act via certain receptors in the animals, the toll-like receptors [TLRs], and, for example, when given around vaccination, we have an improved homogeneity of the vaccination. We do not necessarily increase the antibody response, but we decrease the variation.”
These products can therefore be used in combination with others to promote the production of animals with fewer or no antibiotics, she says.
Collén says this holds a draw for consumers, as many are increasingly concerned about antibiotic resistance, and it also aligns with regulatory pressures facing industry. In addition, Olmix also wants to establish whether incorporation of seaweed into animal diets affects the conduct of animals and thus final product quality.
“I think there is more to come. … There will be more and more development on the use of seaweed extracts for animal nutrition and health,” she says.