FEEDS & FEED PROCESSING MANAGEMENT By David R. Hawkins Michigan State University

COMMON GOALS of FEED PROCESSING 1.Increased feed intake and digestibility 2.Improved feed conversion or efficiency 3. Improved carcass quality and/or yield grade 4. Reduction in feed waste. 5. Lower transportation and storage costs. 6. Reduced labor costs due to increased mechanization.

COMMON GOALS OF FEED PROCESSING 7. Reduced energy costs of processing (drying versus ensiling). 8. Reduced harvest costs (i.e. high moisture corn). 9. Inactivating anti-nutritional factors or specific growth inhibitors 10. Improved cattle health by reduction in digestive disorders (founder, bloat & acidosis).

Feed StuffInhibitorDeactivation Process Cottonseed MealGossypol: Cyclopropane fatty acids; Phytate Add iron salts; rupture pigment gland Soybean MealTrypsin inhibitorHeat, autoclaving Linseed MealCrystalline water-soluble substance Water treatment Raw FishThiaminaseHeat Alfalfa MealSaponins; pectin methyl esterase Limit amount fed Rye5-N-alkyl resorcinolsLimit amount fed Sweet CloverDicoumarolHeat Wheat GermUnidentifiedHeat RapeseedIsothiocyanate; thyroactive materials Heat

DRY PROCESSING of GRAINS Grinding - increases surface area for bacterial digestion. Dry rolling, crimping or cracking - cattle prefer a coarse grind. Popping - Hot air for 30 sec. + rolling. Micronizing - Infrared heat for 3 min. + rolling

DRY PROCESSING of GRAINS Roasting - Heat for a short period of time. Pelleting - grind & force through a die. Extruding - Pressure screw forces grain through a die.

WET PROCESSING of GRAIN Steam rolling - grain exposed to steam for 3 to 5 min. and then rolled. Steam flaking - steam for 15 to 30 minutes. Water content increases to 20%, + rolling. High moisture grain - harvested at 20% to 35% moisture & ensiled. Acid preservation of high moisture grain. Acetic or proprionic acid retards spoilage.

Effects of Processing on the Nutritional Value of Feeds HEAT TREATMENT ˗ to dry certain plant products and to improve the quality of pelleted feeds ˗ employed in the extraction processes to remove oil from some oilseeds. ˗ destroying the trypsin inhibitor which is naturally present in soybean ˗ increases the nutritional value and improves digestibility of cereal grains by gelatinizing starches ˗ steam pelleting results in improved pellet durability and a reduced amount of fines in the finished product.

Effects of Processing on the Nutritional Value of Feeds GRINDING ˗ Grinding may increase the nutritional value of feeds by reducing the particle size ˗ Increasing intake ˗ Increasing the surface area of the ingested feed and facilitating digestion ˗ Grinding process adds metals to feeds from the grinding machinery and can prevent a micromineral Fe, Zn, Cu, Mn, and Na.

Effects of Processing on the Nutritional Value of Feeds PELLETING AND CRUMBLING ˗ compacts the mixed feed ingredients and increases nutrient density and bulk density ˗ improves palatability or acceptability and digestibility of feeds ˗ heat applied during compaction of the pellet may also improve digestibility and destroy thermolabile toxic factors ˗ improves the use of low density, bulky, unpalatable feeds that might not otherwise be practical to use

Effects of Processing on the Nutritional Value of Feeds EFFECT OF PROCESSING ON MOULDS, SALMONELLA, AND OTHER HARMFUL SUBSTANCES ˗ Aflatoxins, produced on some feeds by Aspergillus flavus, are not inactivated by normal pelleting procedures ˗ Prevention of mould growth is the best means to avoid contamination. ˗ Removal and disposal of mould-damaged material is essential ˗ Feeds sometimes contaminated by aflatoxins, such as corn, peanut meal, cottonseed meal, copra, and fish meal

Effects of Processing on the Nutritional Value of Feeds EFFECT OF PROCESSING ON MOULDS, SALMONELLA, AND OTHER HARMFUL SUBSTANCES ˗ Salmonella is killed by pelleting. ˗ Meat meal is a feed ingredient that should be routinely monitored for the presence of salmonella; proper sanitation procedures will reduce the incidence of contamination

Effects of Processing on the Nutritional Value of Feeds EFFECT OF PROCESSING ON THE AVAILABILITY AND NUTRITIONAL VALUE OF VITAMINS ˗ Prolonged heat treatment can destroy the fat soluble and the water soluble vitamins ˗ Such heat treatment can occur during the drying of protein supplements of plant and animal origin. ˗ For example, meat and bone meal contains little or no thiamine as a result of processing. ˗ The water soluble B vitamins are removed during the processing of fish into fish meal. ˗ If insufficient anti-oxidants are present in the feed, pelleting may destroy Vitamins A, E, and K

Effects of Processing on the Nutritional Value of Feeds ˗ Certain trace minerals act as pro-oxidants in feeds and can hasten the oxidative destruction of Vitamins A, D, and E. Manganese and iron are examples of such minerals. ˗ Grinding, coarse wheat flour grinding lose less Vitamin E than fine grinders ˗ Solvent extraction of soybean meal results in the removal of some of the Vitamins E and K ˗ Germinated wheat may have a Vitamin E level as low as 30 percent of ungerminated wheat.

Effects of Processing on the Nutritional Value of Feeds EFFECT OF PROCESSING ON THE AVAILABILITY AND NUTRITIONAL VALUE OF TRACE MINERAL ELEMENTS ˗ Generally, the availability of minerals is not affected by processing. ˗ The availability of zinc is sometimes enhanced by addition of the chelate EDTA. ˗ Pelleting and crumbling do not affect trace mineral levels in feed