Macroalgae and pig nutrition and health are not well-known animal feed ingredients. Yet, algae can be valuable in piglet rearing on three different aspects: nutritional value, the functional value of its active principles and technological value.
Microalgae’s nutritional benefits
Its use as a source of nutrients came from farmers living close to the sea who found that by adding seaweeds to a pig’s diet could improve performance. Currently, Algae is recognized by a number of feed experts that the supply of minerals in its organic form ensures a better assimilation. Algae such as Ulva sp (also known as green lettuce) are rich in key minerals such as iron, manganese, copper, iodin and zinc.
Algae also contain many trace elements that no feed formulation takes in consideration, because science has not yet determined its properties and necessary levels in the pig diet. Often referred as “unknown growth factors,” these trace elements balance the pig diet from lacks feed experts cannot currently identify.
When algae were introduced to animal husbandry on a large scale 10 years ago, it was not for its nutritional value, but for its technological properties. Ulva lactuca polysaccharides were used to intercalate layers of a smectite clay, montmorillonite, giving birth to a new hybrid material Amadéite.
Beside its potential uses in various industries such as plastics, ceramics or cosmetics, this material has a high capacity to bind Deoxynivalenol (DON) and Fumonisins (FUM) in pigs. It’s found to be more efficient than active charcoal without impairing the bioavailability of nutrients in the small intestine (Avantagiatto et al, 2003, 2004, 2007; Döll et al, 2004; Havenaar et al, 2006).
Algae’s efficiency in preventing adverse effects of mycotoxins on reproductive, health and growth performances of pigs is recognized by MMi/MT.X+ users worldwide.
Soon after the Amadéite, different users from the five continents have reported an improvement of pig performances with MTX°+ even when no mycotoxins were detected in the feed. Rapidly, the algae are presumed to play an important role in this phenomenon.
Over the six months of the life of a farmed pig, its digestive tract will encounter a lot of different challenges. From a piglet’s development and growth of the villi, which is very fragile because the equilibrium of the microflora is easily subjected to dysbacteriosis. Supporting a piglet’s digestive tract from the very first days of life will ensure its good development, and prevent digestive troubles during critical periods, such as weaning.
In this, algae polysaccharides appear to be good candidates. Stemming from a specific genetic evolution that made them resist through huge environmental changes over millennia, they are molecules with unique properties.
“The marine polysaccharides such as ulvans contain rare sugars such as rhamnose and high sulfate content. These poly-anionic structures are associated with various biological activities”, says Dr Henri Salmon, director of research at the National Institute of Agronomic Research, during the first Algae Symposium held in Pontivy, Brittany in September 2012.
Marine Sulphated Polysaccharides (MSP) show three main points of interest: they are very reactive, because of their sulfate radicals they offers a wide range of functionalities and are unique, as none of them is found in superior plants.
Different studies have highlighted the capacity of ulvans to stimulate mucin secretion in the intestinal tract (Barcelo and Al. 2000). Mucins are determinant for piglet gut health, as they are known to bind some viruses and to inhibit the adhesion of different pathogenic bacteria on the intestinal wall. This is consistent with recent results obtained on 800 piglets in Spain (Tests and Trials, 2011) and on 5,000 piglets in Germany (integrated farm, 2012), with Ecopiglet. All results are coming together: decreased sow digestive troubles in maternity, improved growth and lower use of antibiotics, for a better financial performance (see Table 1 and Table 2).Stimulating mucin secretion or pillarising Montmorillonite is not all of it: marine sulfated polysaccharides have more than one string to their bow.
“MSP have been shown to have antiviral, anti-inflammatory, antioxidant, anticoagulant and antithrombotic activities,” says Dr. Salmon. “Algal sulfated polysaccharides are a new source of numerous biological activities that may find in human and animal health many prophylactic and therapeutic benefits.”
Literature widely describes the antibacterial activities and immune modulation properties of macroalgae, raising the interest of animal husbandry stakeholders to understand their mode of action and use them as natural additives in pig feed. The next challenge for companies promoting the use of algae is to isolate the different active principles of macroalgae (green, brown and red) by enzymatic extraction, to provide more natural and specific products for animal and plant nutrition and health.