Algae and microalgae stand out as renewable sources of nutraceutical foods, medicines and cosmetics, biostimulants and inputs for organic farming and environmental remediation. (1)
In animal husbandry, the use of these substances as dietary feeds with special nutritional purposes makes it possible to improve the health condition of animals. Minimizing the use of antibiotics. The solution is before the eyes of those who want to open them and has already been successfully tested, just in Italy. The Algatan case.
Antibiotics and antibiotic resistance
Antibiotic resistance is described in the WHO (or WHO) report 29.4.19 as the most serious threat to the health of humanity. Its cause lies in the excessive and inappropriate consumption of antibiotics, on farms as well as by humans.
Research in medicine is therefore turning toward substances that can strengthen the immune system through its gut microbiome, as the ‘command center’ of the immune system. Thus it was possible to verify the effectiveness of probiotics and prebiotics, vitamin and mineral mixes, Omega 3, and microalgae.
Algae, microalgae and Omega 3 for animal health
In pig farming, as early as the weaning stage digestive problems in piglets can lead to the use of antibiotics to restore intestinal health. Two experimental studies have shown the ability of Chlorella vulgaris and Spirulina platensis to improve nutrient digestion and assimilation. Reducing, respectively, the incidence of diarrhea and the need to employ antibiotics (2,3).
In poultry farming, the higher polyunsaturated content makes broiler meat and eggs more susceptible to oxidation. The administration of microalgae mitigates this phenomenon, thanks to antioxidants that are conversely not present in other sources of Omega-3 (e.g., fish oil). (6) Omega-3s have then shown positive effects-in pigs and poultry-on the immune system but also on growth and fertility and bone strength. (5)
Algae and microalgae for cattle
In cattle husbandry, as seen, the addition of minimal shares (2%) of red algae(Asparagopsis) in feedstuffs enables a reduction (-99%) of ruminant greenhouse gas emissions. And this is precisely one of the major challenges outlined by FAO to reduce the contribution of livestock supply chains to climate change.
In turn, the use of microalgae in livestock feed can reduce dependence on terrestrial crops (e.g., soybean, corn) and greenhouse gas emissions. In addition to improving the nutritional and health properties of foods of animal origin. (6) Thus, it has been shown that feeding certain microalgae to cattle promotes an optimal ratio of Omega-3 to Omega-6 and increased CLA (conjugated linoleic acid) content in their meat. (7)
Microalgae in aquaculture and beekeeping
In aquaculture Microalgae are ideal candidates to replace fish-based feeds, which are often unsustainable. Due to their richness in protein, Omega-3 and bioactive substances (e.g., carotenoids) with antioxidant, immune-stimulating and growth-promoting actions. They are widely used for the rearing and care of various fish as well as bivariate shrimps and mollusks. With favorable effects on, among other things, spawning and reproduction.(8)
In beekeeping, monitoring nutritional status is essential to ensure bee health, as malnutrition makes adverse effects from pests, pathogens and pesticides more impactful. The biochemical profile of microalgae, comparable to that of pollen (proteins, lipids, micronutrients, antioxidants, and prebiotics), makes them a valuable replacement food for employed honey bees in natural pollen deficiency. In this way, mortality in colonies in beekeeping can be reduced by pesticide- and antibiotic-free feeding (compared with non-organic terrestrial crops). (9)
Fig. 1. Similarities of functional and nutritional properties between pollen (orange text) and microalgae (green text) that detect for honey bee health (Ricigliano, 2020)
Microalgae for agriculture
‘Biostimulants are substances and/or microorganisms that applied to the plant […] improve nutrient uptake and assimilation efficiency, tolerance to abiotic stresses, and product quality.’ (10) Microalgae have shown excellent potential as biostimulants (mainly due to the action of polysaccharides). With positive influence on nutrient uptake, physiological state and production yield of plants, which increase resistance to biotic and abiotic factors. (11)
Soil fertility is also enhanced by the contributions of organic matter and various macro- and micronutrients, offered by microalgae in agriculture. Cyanobacteria (e.g., spirulina) are also able to provide nitrogen to crops by converting atmospheric nitrogen into its forms available to plants (so-called algalization). Cyanobacteria and green microalgae then produce various anti-microbial substances, growth stimulators, and microbial communities useful in defense against pathogens. (12)
Microalgae and the circular economy
Soil erosion and the loss of surface fertile layers, either by natural agents or agricultural activities, can affect its productivity. Many green microalgae and cyanobacteria are capable of producing EPSs (extracellular poly-saccharides) that enable the removal of phenols from industrial wastewater (e.g., the oil industry), thus allowing it to be used as growing water without compromising the soil microbial flora. (13) Such matrices also help prevent erosion and maintain soil structure. (14)
Fig. 2. Positive effects of algal-derived polysaccharides on shoots and roots (Joan-Chanda et al., 2019)
Potential limitations to the use of microalgae in agriculture relate to the high amounts of biomass required for nutrient supply. Therefore, there is a need to develop research on synergistic effects of algae and/or microalgae mixes. (15) Another possible solution is to inoculate microalgae directly into the soil as a growing environment where they themselves can progressively develop, continuously providing nutrients and other benefits to crops. (16)
Fig. 3. Benefits and application methods of algal inoculums in agriculture (Renuka et al., 2018)
Algatan, the miracle in animal husbandry
Algatan is a line of innovative products developed by LT Natural Group S.r.l. (a historic Cremona-based feed material supply company) during 15 years of research and development. Extensive experimentation in various livestock and agricultural settings has resulted in the development and patenting of a series of mixes of algae, microalgae, and tannins.
In vitro and in vivo tests have demonstrated the ability of some Algatan products to fight pathogenic bacteria such as:
– Campylobacter jejuni, which is ubiquitous in poultry (37%) according to the EFSA-ECDC report on zoonoses in the EU, Salmonella spp, (which has topped the list of food and feed alerts in Europe for years) and Staphylococcus aureusin poultry and and pigs,
– Escherichia coli, Staphylococcus aureus, Clostridium perfrigens and Salmonella typhimurium, (ranked second for human salmonellosis, with evidence of resistance to several classes of antibiotics). In vitro trials, with good results in growth inhibition.
Algatan and animal welfare
Trials on farms have demonstrated the efficacy of Algatan products in inhibiting the mentioned pathogens. Their administration has thus reduced the use of antibiotics. To the point of eliminating their use altogether, in subsequent generations, due to transmission by matriarchal lineage of the microbiome with enhanced immune defenses. A big step forward in the fight against antibiotic resistance, which is already a cause of cost and damage in animal husbandry. (17)
Animal welfare is improved–on pigs and rabbits, poultry, sheep and cattle species–in concrete terms of reproductive efficiency, attenuation of oxidative stress, bactericidal/bacteriostatic effect, modulation of microbiota and weight gain. With appreciable results now being further studied to verify the repeatability of the experiments performed.
Algatan in agriculture
The antibacterial and biostimulant activity of Algatan GEA soil conditioner has been subjected by the University of Molise (Department of Agriculture, Environment and Food) to several tests, in vitro and in vivo. Which show inhibitory activity, in particular, on various phytopathogens of the genera Pseudomonas, Bacillus, Xanthomonas and Pectobacterium.
Appreciable results were observed on tomato in terms of plant growth and resistance, antioxidant richness in fruits. In olive trees, the incidence of desiccation caused by Xylella fastidiosa subsp. pauca. (18)
Fig. 4. Difference in the health status of olive plants treated with ALGATAN® and without treatment.
Dario Dongo and Andrea Adelmo Della Penna
Notes
(1) Camacho et al. (2019). Potential industrial applications and commercialization of microalgae in the functional food and feed industries: A short review. Mar. Drugs 17:312, doi:10.3390/md17060312
(2) Furbeyre et al. (2017). Effects of dietary supplementation with freshwater microalgae on growth performance, nutrient digestibility and gut health in weaned piglets. Animal 11(2):183-192, doi:10.1017/S1751731116001543
(3) Furbeyre et al. (2018). Effects of dietary supplementation with Spirulina and Chlorella on growth and digestive health in piglets around weaning. Animal 11(2):183-192, doi: 10.1017/S1751731118000125
(4) Ribeiro et al. (2013). Direct supplementation of diet is the most efficient way of enriching broiler meat with n-3 long-chain polyunsaturated fatty acids. British Poultry Science 54(6):753-765, https://doi.org/10.1080/00071668.2013.841861
(5) Lee et al. (2018). Review on docosahexaenoic acid in poultry and swine nutrition: Consequence of enriched animal products on performance and health characteristics. Animal Nutrition 5:11-21, https://doi.org/10.1016/j.aninu.2018.09.001
.
(6) Gatrell et al. (2014). Nonruminant Nutrition Symposium: Potential of defatted microalgae from the biofuel industry as an ingredient to replace corn and soybean meal in swine and poultry diets. J. Anim. Sci. 92(4):1306-14, doi: 10.2527/jas.2013-7250
(7) Carvalho et al. (2018). Performance, insulin sensitivity, carcass characteristics, and fatty acid profile of beef from steers fed microalgae. J. Anim. Sci. 96(8):3433-3445, doi: 10.1093/jas/sky210
(8) Yarnold et al. (2019) Microalgal aquafeeds as a part of a circular bioeconomy. Trends in Plant Science 24(10):959-970, https://doi.org/10.1016/j.tplants.2019.06.005
(9) Ricigliano (2020). Microalgae as a promising and sustainable nutrition source for managed honey bees. Arch. Insect Biochem. Physiol. 104(1):e21658, https://doi.org/10.1002/arch.21658
(10) EBIC(European Biostimulant Industry Council). Definition adopted in 2013. http://www.biostimulants.eu/
(11) Chanda et al. (2019). Microalgae polysaccharides: the new sustainable bioactive products for the development of plant bio-stimulants? World Journal of Microbiology and Biotechnology 35:177, https://doi.org/10.1007/s11274-019-2745-3
.
(12) Renuka et al. (2018). Microalgae as multi-functional options in modern agriculture: current trends, prospects and challenges. Biotechnology Advances 36:1255-1273, https://doi.org/10.1016/j.biotechadv.2018.04.004
(13) Surkatti et al. (2018). Microalgae cultivation for phenolic compounds removal. Environmental Science and Pollution Research 25:33936-33956, https://doi.org/10.1007/s11356-018-3450-8
(14) Xiao et al. (2016). Overview of microalgal extracellular polymeric substances (EPS) and their applications. Biotechnol. Adv. 34(7):1225-1244, https://doi.org/10.1016/j.biotechadv.2016.08.004
(15) Cabanelas et al. (2013). Comparing the use of different domestic wastewaters for coupling microalgal production and nutrient removal. Bioresour. Technol. 131:429-436, https://doi.org/10.1016/j.biortech.2012.12.152
(16) Ronga et al. (2019). Microalgal biostimulants and biofertilisers in crop productions. Agronomy 9:192, doi:10.3390/agronomy9040192
(17) Alòs (2015). Antibiotic resistance: A global crisis. Enfern. Infecc. Microbiol. Clin. 33(10):692-9, doi: 10.1016/j.eimc.2014.10.004
(18) The intervention on the olive trees supplemented the use of Algatan with treatments to control the vector (the spittlebark, Philaenus spumarius), pruning interventions (to remove damaged parts of the plant), and soil tillage
Dario Dongo, lawyer and journalist, PhD in international food law, founder of WIISE (FARE - GIFT - Food Times) and Égalité.
Graduated in Food Technologies and Biotechnologies, qualified food technologist, he follows the research and development area. With particular regard to European research projects (in Horizon 2020, PRIMA) where the FARE division of WIISE Srl, a benefit company, participates.
