Algae in pig feeds: An ingredient from the future

The sector of algae cultivation for pig feed has an exponential growth and is poised to become an impressive market. The use of algae as an animal feed has increased 8 percent each year for the past 30 years, according to experts.

Brown seaweed are one of the most promising varieties to be used in animal feed.
Brown seaweed are one of the most promising varieties to be used in animal feed.

The sector of algae cultivation for pig feed has an exponential growth and is poised to become an impressive market. The use of algae as an animal feed has increased 8 percent each year for the past 30 years, according to experts. 

Algae cultivation

The Earth has seven production basins of brown seaweed, with Asia being at 75 percent and Northern Europe coming last with only 2 percent of world production. The required conditions for the cultivation of seaweed are cold water with no ice. Nevertheless, the real challenge is to establish a viable seaweed industry and bring the development of seaweed cultivation within regional development.

Algae cultivation is very promising as they do not need fertilizers, freshwater or pesticides and require on average one-sixth of the surface needed by terrestrial plants. In contrast with terrestrial plants that draw nutrients from their roots, algae absorb nutrients from their entire surface greatly increasing productivity. 

Moreover, their colloidal structure, which allows greater water retention, provides to algae twice the dry matter than terrestrial plants. These properties are well-known and appreciated especially in Canada and Norway, where a significant production of Ascophyllum meal is being produced for animal nutrition. From the brown seaweed of the Fucales family, Ascophyllum is particularly interesting for its vitamin, mineral and protein concentration. It is also known for its powerful binding properties.

Nutritional value

The interest for seaweed cultivation is not new: It dates back to the Neolithic period, where it was used as fertilizer, feed and fuel. Nevertheless, research on algae started in the second half of the nineteenth century, with the creation of marine stations of Concarneau (1859) and Naples (1872), followed by the start in 1872, of the laboratory of experimental zoology now known as biological Station of Roscoff. 

Because of their particular properties, macroalgae are often too reserved for specialty markets, something that makes their use in animal feed currently cost prohibitive. The nutritional value of algae is augmented by the abundance in minerals, fiber, proteins, vitamins and lipids depending on the variety, as shown in Table 1 . In the animal feed industry, seaweed meals are increasingly used as a dietary supplement, but seaweed extracts still remain quite inaccessible economically.

Algae can be used as a functional fiber complementary to other prebiotics, according to empirical evidence from French researchers. In other roles, algae are used in small quantities over a short period of time, often as a supportive measure. This is the case with lithothame and fossil calciferous algae, which has a structure of calcium carbonate and magnesium.

Health properties

Applications of seaweed are numerous but currently the chemical industry is the main market as algae is a source for gelling agents, alginate or carrageenan. Nevertheless, scientific research has begun to demonstrate the positive effects of seaweed in health and nutrition of humans and animals. Current research has focused on the immune stimulation action and anti-inflammatory effects of marine sulfated polysaccharides (MSP). 

Depending on the type of polysaccharide, there is a general positive action on innate immunity, with different mechanisms of cell recognition and many types of pathways (activation of the complement, of the lymphocytes, production of cytokines). Other publications have reported positive antiviral effects, regulation of inflammation process, significant anticoagulant properties and anti-tumoral activity. Most of these activities have been observed or measured in cell cultures or experimental animals (rats); but the potential is to be applicable to productive animals.

Algae and animal feed

Several projects in France are working toward developing processes to make algae cultivation economically viable as an animal feed, in the same terms as wheat and corn. Current priority is to find areas for cultivation, which traditionally comes from the shellfish industry. The next step after seaweed farming is offshore marine aquaculture with shellfish and seaweed culture on the same site (open ocean aquaculture).

For now, cultivated seaweed in Europe is an underused animal feed ingredient. Perhaps, it is because algae are not common in European human diets compared to the extensive use of algae in the Asian cuisine. On the other hand, wild resources do not present a very important supply. Green seaweed is rich in indigestible fiber and is good for health but not suitable for animal growth. 

Further research is needed to reduce the obstacle represented by the high-fiber concentration and improve protein digestibility to transform seaweed into an animal feed ingredient. By mixing several species, the final product can be a nearly "complete diet" as long as there is enough control of the conditions of biomass production. To this end, significant variations of chemical composition of seaweed actually make their use currently challenging, hence the necessity for further research on this issue. Regarding microalgae, operating conditions are even more delicate and complex, which makes them cost prohibitive. Microalgae fat content is particularly suitable for the biodiesel industry, and many projects are being set up to develop this variety for use in animal nutrition.

There is still much work to be done until we can start producing a viable animal feed ingredient, but current research projects are numerous and very promising. Unfortunately, Europe has no agronomic approach toward algae, in contrast to many Asian countries that grow algae the same way as vegetables.

Page 1 of 61
Next Page