What a re r Lipids? What a re r Fatty y Ac A ids?

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1 Beef Cattle In-Service Training Inclusion of Lipids into Beef Cattle Diets Reinaldo F. Cooke, Ph. D. Oregon State University EOARC, Burns What are Lipids? Organic compounds Plant and animal compounds Insoluble in water Soluble in organic solvents (i. e. ether) Several types of lipids VFA, triglycerides, cholesterol, fat soluble vitamins (A, D, E, and K) Major energy source Twice energy content of carbohydrates Starch, sugars, and digestible fiber 1

2 What are Lipids? Triglycerides - applicable for cattle nutrition Main component of vegetable and animal fat 1 glycerol + 3 fatty acids What are Fatty Acids? Chain-molecules containing C, H, O Backbone of lipid nutrition Mainly classified according to Chain length (number of carbons) Hydrogenation (number of double-bonds) bonds) 2

3 What are Fatty Acids? Classified according to number of carbons Short-chain FA = Less than 6 carbons VFAs (acetate, propionate, butyrate) Medium-chain FA = 6 to 12 carbons Long-chain FA = more than 12 carbons Energy reserves in plants and animal tissues Acetate (2 carbons) Palmitic acid (16 carbons) What are Fatty Acids? Classified according to hydrogenation Presence of double bonds in chain Saturated, monounsaturated, polyunsaturated Stearic acid (18:0) saturated Oleic acid (18:1) monounsaturated Linoleic acid (18:2) polyunsaturared 3

4 What are Fatty Acids? Classified according to hydrogenation Within mono and polyunsaturated Classification according location of first double bond Oleic acid (18:1) Omega - 9 Linoleic acid (18:2) Omega - 6 Linolenic acid (18:3) Omega - 3 What are Fatty Acids? Essential fatty acids Not synthesized by body tissues Nutritional requirements still unknow Required for many physiological processes Must be present in the diet Linoleic acid (18:2) Omega - 6 Linolenic acid (18:3) Omega - 3 4

5 Main objective Energy source, increase energy density of diet 1 g fat = 9 cal, whereas 1 g of starch/protein = 4 cal Important for dairy and feedlot cattle Additional effects Individual fatty acids modulate body functions Reproduction, health, carcass quality Inclusion of fat sources into cattle diets Enhance uptake and prevent ruminal disorders Requires evaluation of diet and fat sources Common lipid sources fed to cattle Saturated fatty acids Hydrogenated fats, yellow grease, palm oil Monounsaturated fatty acids Canola oil, hydrolyzed tallow Polyunsaturated fatty acids Linoleic acid (omega 6) Oilseeds such as cottonseed, corn, soybean and safflower Linolenic acid (omega 3) Green forages Oilseeds such as linseed and camelina 5

6 Sources constituted mainly by triglycerides Digestion occurs in mouth, rumen, abomasum, and small intestine Rumen = Major modification in lipids Hydrolysis Microbes break triglycerides into glycerol and fatty acids Fermentation Microbes ferment glycerol mainly into VFA Biohydrogenation Fatty acids exert antimicrobial effects, specially PUFA Addition of H to double bonds by ruminal microbes Priority for microbes, delaying or preventing CHO digestion 6

7 Absorption in the small intestine Virtually identical as content that leaves rumen Reach circulation and are stored into tissues Excessive intake of lipid sources Accumulation of PUFA in the rumen Incomplete biohydrogenation Antimicrobial effects Detrimental effects on digestibility Adequate inclusion to optimize utilization and prevent harm on ruminal digestibility 7

8 Supplementing fat to cattle Highly evaluated within high-grain grain diets Less attention to forage-fed fed cattle Hess et al. (2008) JAS 86:E Fat inclusion into forage-based diet Less than 2% of DM to prevent forage substitution Less than 3% of DM to maximize diet efficiency Less than 4% of DM to increase diet density While preventing detriment to ruminal digestibility Practical examples Beef cows (1200 lb) consuming low-quality hay 2.5% of BW = 30 lbs/day of hay DM Supplemented with soybean oil (100% EE) OR Supplemented with camelina meal (18% EE) Included at 3% to maximize diet efficiency Feed 0.9 pounds of soybean oil OR Feed 5 pounds of camelina meal 8

9 Fat as additional energy source Flaxseed supplementation to cattle Grazing summer range Supplemental fat included at 3.2% of diet DM Scholljegerdes and Kronberg, 2010 Fat as nutraceutical source Feed that provides health benefits Essential fatty acids (18:2 and 18:3) Modulate body functions and provide energy Linoleic Acid (18:2) Linolenic Acid (18:3) Arachdonic Acid EPA and DHA Prostaglandin Family 2 Pro-inflammatory effects CL regression + Uterine involution Prostaglandin Family 3 Anti-inflammatoryinflammatory Pregnancy maintenance 9

10 Essential fatty acids (18:2 and 18:3) Highly susceptible to ruminal biohydrogenation Practical example Forage-fed beef cows receiving: Control = no supplemental fat 0.9 lbs/d of tallow = 100% EE, with 0.5% as 18:3 0.9 lbs/of flaxseed oil = 100% EE, with 56% as 18:3 Control Tallow Flaxseed oil 18:3 consumed (g/d) g :3 biohydrogenated (g/d) :3 reaching intestine (g/d) g 76.1 % of biohydrogenation loss 93% 91% 85% Example: 18:3 and Pregnancy Rates to AI Study 1 = Raw flaxseed Study 2 = Formaldehyde-treated flaxseed Study 3 = Rolled flaxseed P = 0.04 P < 0.01 Colazo et al. (2004) Petit et al. (2001) Ambrose et al. (2006) 10

11 Ruminal-protected fat sources Fat (or part of it) becomes inert in the rumen Prevents antimicrobial effects Prevents biohydrogenation Several approaches Hydrogenation/saturation of fatty acids Chemical treatments (Na alginate, formaldehyde) Calcium-soaps of fatty acids Several others Highly depended on rumen variables Essential fatty acids (18:2 and 18:3) Ruminal protected sources Practical example Forage-fed beef cows receiving: Control = no supplemental fat 0.9 lbs/d of raw soybean oil = 100% EE, with 53% as 18:2 0.9 lbs/of CSFA soybean oil = 85% EE, with 53% as 18:2 Control Raw SB CSFA SB 18:2 consumed (g/d) / 396 g :2 biohydrogenated (g/d) :2 reaching intestine (g/d) / 235 g % of biohydrogenation loss 79% 79% 47% 11

12 Example: Rumen-protected PUFA source Plasma PUFA, mg/g Plasma TNF-a, pg/ml During preconditioning (1.7 % inclusion, d - 30 until d 0 = feedlot transfer) P < 0.01 No fat P < 0.01 CSFA SB No fat CSFA SB Day of the study No fat P = 0.06 CSFA SB Feedlot ADG (lbs/d) Example: Rumen-protected PUFA source Beef cows following fixed-time AI or ET (0.6% inclusion) P = 0.07 P = 0.02 No fat x CSFA SB Fixed time AI No fat x CSFA SB Fixed-time ET CSFA Palm Oil x CSFA SB Fixed time AI Lopes et al. (2009) 12

13 Proper adaptation period EFA supplementation requires adaptation Maximize intake Change FA profile in tissues and circulation Ceruloplasmin (mg/dl) P = 0.50 CO PF Haptoglobin (abs 450 nm x 100) P < CO PF Day of the study Day of the study No adaptation period 30 d adaptation period Final Conclusions Fat supplementation benefit performance Increasing energy density of the diet Nutraceutical effects of essential fatty acids Dietary inclusion should respect limits Particularly forage-fed fed cattle Prevent rumen digestibility problems EFA should bypass biohydrogenation Fat sources should introduced gradually Adaptation for proper intake / EFA tissue uptake 13