NONRUMINANT NUTRITION SYMPOSIUM: Potential of defatted microalgae from the biofuel industry as an ingredient to replace corn and soybean meal in swine and poultry diets12

Abstract

While feeding food-producing animals with microalgae was investigated several decades ago, this research has been reactivated by the recent exploration of microalgae as the third generation of feedstocks for biofuel production. Because the resultant defatted biomass contains high levels of protein and other nutrients, it may replace a portion of corn and soybean meal in animal diets. Our laboratory has acquired 4 types of full-fat and defatted microalgal biomass from biofuel production research (Cellana, Kailua-Kona, HI) that contain 13.9 to 38.2% crude protein and 1.5 to 9.3% crude fat. This review summarizes the safety and efficacy of supplementing 2 types of the biomass at 7.5 to 15% in the diets of weanling pigs, broiler chicks, and laying hens. Based on their responses of growth performance, egg production and quality, plasma and tissue biochemical indicators, and/or fecal chemical composition, all 3 types of animals were able to tolerate the microalgal biomass incorporation into their diets at 7.5% (on as-fed basis). Holistic analysis is also provided to explore the global potential of using the defatted microalgal biomass as a new feed ingredient in offsetting the biofuel production cost, reducing the dependence on staple crops such as corn and soybeans, decreasing greenhouse gas production of animal agriculture, and developing health value-added animal products.

Biochemical characterization of microalgal biomass from freshwater species isolated in Alberta, Canada for animal feed applications

“…Under identical culture conditions in 1000 L, artificially illuminated, enclosed photobioreactors, the species were virtually indistinguishable in terms of growth rates (0.9-1.0 d ) and there appeared to be little differences with regard to their appearance, texture and smell; all of which have important implications for animal feeding [38][39][40][41]. Recent studies have shown that while the nutritional value of certain algal biomass for animal feeds may be as high (or even exceed) conventional plant sources (e.g., soy and corn), recommended dietary inclusion levels for certain farmed animals (e.g., swine and poultry) have been minimized (b 10% of the diet) due to low feed intake as a result of unattractive smell and off-flavors [17,42].…”

“…lower aerial foot-print, wastewater mitigation), carbon credits (e.g., industrial CO 2 conversion), nutritional value (e.g., more favorable EAA and EFA profiles) and raw ingredient sustainability [15]. As such, it is not surprising that algal products/co-products resulting from biofuel applications have been identified in Canada and elsewhere as a priority for further investigation as valuable commodities for sustainable development of terrestrial livestock and aquaculture feed inputs [16,17]. However, the nutritional content of algal biomass is poorly defined and for most species, including well-studied species like Chlorella, there is little consensus on their biochemical composition between and within species/strains and data on known and not-so-well known species isolated in Northern climates has not been reported, especially for LEB.…”

Algal Proteins: Extraction, Application, and Challenges Concerning Production

“…The replacement of up to 33% of soy proteins with proteins from Arthrospira maxima , A. platensis , and C. vulgaris in pig feed has been reported as being suitable without any adverse effects [158]. The effect of feed processing appears to play a role in the utility of Spirulina in pig’s feed.…”

In vitro digestion of microalgal biomass from freshwater species isolated in Alberta, Canada for monogastric and ruminant animal feed applications

“…Although algal oil for third generation biodiesel production has been the subject of much research and a major driver for technological innovations in recent years, by most assessments it is still not economically viable [2][3][4]. Consequently, algal products/coproducts resulting from biofuel applications have been identified in Canada and elsewhere as a priority for investigation as valuable commodities for revenue generation and sustainable replacement of terrestrial livestock and aquaculture feed inputs [4][5][6]. Four freshwater species isolated in Northern Alberta, Canada have been identified as promising candidates for industrial carbon conversion in Northern climates; including Chlorella vulgaris, Nannochloris bacillaris, Tetracystis sp.…”