What do the Experts Say about Replacing Fish in Fish Food

What do the Experts Say about Replacing Fish in Fish Food

History of Fish Diets The original extruded fish diets were primarily soy Based. Soy based diets extrude very well and fish grew. PROBLEMS: Fish didn t taste much like their wild counter parts Water Quality Feed Efficiency

BASIC NUTRITION Series of processes by which an organism takes in and assimilates food for maintenance, growth, production and reproduction

NUTRIENT Chemical element or compound that is required in the diet of a given animal to permit normal functioning:

CLASSES OF NUTRIENTS: Amino Acids Carbohydrates Fatty Acids Vitamins Minerals

CARBOHYDRATES Various combinations of carbon and water NFE: Fiber: Plants: Sugars Starches - amylose, glycogen Structural - hemicellulose, cellulose, lignin Energy storage and structure Animals: Metabolic fuel - available energy

FAT Combination of C, H, and O Triglycerides - three fatty acids esterified to a glycerol Certain fatty acids are essential Other lipids Most concentrated form of energy storage Long-term energy storage in animals

PROTEINS Combination of C, H, O and N Made of many amino acids linked end to end Animals structure ad function: Scales, skin Hemoglobin, insulin, actin & myosin No protein requirement, per se

Dietary Protein Most expensive component of diet Protein quality (not quantity)most important Historically Fish Meal has been best fish protein to grow fish 100s of scientific papers on the replacement value for a protein source always compare to fish meal as the gold standard

DIGESTION Small Intestine - Enzymatic Degradation Carbohydrates: Amylases, Lactase, Sucrase Fats: Bile Salts, Lipases Proteins: Proteases, Trypsin, Chymotrypsin, Peptidases

DIGESTION Consumed Absorbed* Carbohydrates Simple Sugars Fats.Fatty acids, glycerol Proteins..Amino acids *Absorbed into blood or lymph

GI TRACT Reflects an animal s eating habits Complexity Length

Digestion and Absorption What about fiber? Plants contain fiber. FISH No foregut fermentation Little or no hindgut fermentation Mastication/grinding Carp - pharyngeal teeth Milkfish, gizzard shad - gizzard Grass Carp

Fish Efficiency of converting food into meat or eggs FCR (feed conversion ratio; units = g food per g gain Cattle = 6-8 Hogs = 3 Chickens = 2-3 Fish = 1-1.5 These efficiencies are under optimal conditions, and will drop with underfeeding or overfeeding!

GI Tract Land Animals»Sheep 35:1, Ruminants»Pigs 14:1, sacculation»cats 4:1, simple

Terrestrial Animal Stevens and Hume, 1996

GIZZARD SHAD >5 x B.L.

Bluegill: B.L. = 20 cm G.I.T. = 24 cm G.I.T.:BL = 1.2

Fish Diets Why are fish so efficient? -Fish have reduced energy requirements - Cold blooded (poikilothermic) - energy not needed to maintain body T - Aquatic - not fighting gravity - able to excrete nitrogen more easily - Generally utilize readily available nutrients - e.g., unlike a cow that needs microbial digestion to use it s food

FISH vs. TERRESTRIAL ANIMALS Carbohydrate Utilization Little amylase activity = varies Warm vs. Cold water species Fresh vs. Salt water species Cooked vs. Raw starch Aquatic vs. Terrestrial Carbohydrate

Carnivorous & Omnivorous Carnivorous: Trout, Bass, Perch, Walleye, Bluegill All Starting fish Protein-based diets Omnivorous: Catfish, Carp, Koi, Tilapia Can utilize some carbohydrates

Effect of replacing dietary fish oil with Soy Oil in cobia SO can replace a substantial amount of FO in aqua feeds. Production performance is largely unaffected by partial replacement of FO with SO FA composition is significantly altered, even at low levels of FO substitution. Aggressive FO replacement may result in development of EFA deficiency, particularly in reduced-fish meal Formulations. Fisheries and Illinois Aquaculture Center, Southern Illinois University Carbondale, Carbondale, IL; 2 Virginia Seafood Agricultural Research and Extension Center, Virginia Tech, Hampton, VA; 3 International Initiative for Sustainable and Biosecure Aquafarming, Norfolk, VA, USA; 4 Marine Fish Culture Laboratory, Institute of Oceanography, Federal University of Rio Grande, Rio Grande, RS, Brazil

Effects of replacing fish meal with SPI on growth and nutrient utilization in Rainbow Trout Soy protein concentrate can replace 50% of the fish meal in high-lipid, extruded diets for rainbow trout without reducing performance.. Replacing 75 or 100% of the fish meal with soy protein may reduce growth because of lower feed intake and low lipid digestibility. M Mambrini, A J Roem, J P Carvèdi, J P Lallès and S J Kaushik

Insect-based fish feed for rainbow trout Black soldier fly (Hermetia illucens) Sophie St-Hilaire1, Wendy Sealey2, Mark A. McGuire2Jeffery Tomberlin3, Craig Sheppard4, Larry Newton4, MirielleChahine2, Mario De HaroMarti 2, and Carolyn Ross 5 1Idaho State University2University of Idaho 3Texas A &M University 4University of Georgia5 Washington State University

Insect-based fish feed for rainbow trout Black soldier fly (Hermetia illucens) Between 20 and 50% reduction in phosphorus and nitrogen in remaining material Pupae by-product is a suitable animal grade foodstuff ~40% protein ~30% fat

Insect-based fish feed for rainbow trout Control diet 25% fishmeal 25% replacement fishmeal replacement 50% fishmeal replacement Change Weight gain (g) Feed Conversion Ratio * 2054a 1815a,b 1559b -25% 1.18a 1.22a 1.47b -20%

Human Health and Nutrition American Heart Association recommends the consumption of oily fish at least twice a week1 Omega-3 content of farmed fish depends on the FO levels in fish diets2 Determines health benefits of seafood consumption Example: consumption of salmon raised on the high-fo diet reduced triglycerides and improved other health indicators of patients with coronary heart disease These effects were not significant in patients consuming salmon raised on low-fo diets2 1 Lichtenstein et al. 2006, 2 Seierstad et al. 2005

Reducing fish meal and fish oil inputs in feed Feed is the largest production cost for commercial aquaculture thus improving feed efficiency in industrial systems is already a priority Research to develop substitutes for FM & FO is now focused on commodities such as oilseeds (especially soybeans), meat byproducts (such as blood meal and bone meal) and microbial protein complete replacement of fish meal and fish oil in aquaculture feeds faces severe barriers

Fish Meal Replacement: AquaMax Primary goal - to replace FM and FO in fish diets 33 partners, 14 countries Four years of research and $21.6 MM Replacement of FM with a mixture of corn gluten, wheat gluten, soy concentrate, krill meal, and amino acids resulted in 17% weight reduction of fish Salmon weight (kg) 4.5 4.0 3.5 3.0 2.5 2.0 1.5 1.0 0.5 0.0 a b b 30% FM + 6.5% FO 12% FM + 16% FO 12% FM + 7% FO Torstensen et al., 2008 *Bars not sharing a common letter are significantly different (P < 0.05)

Questions