Feeding Guide 4th Edition
About the author
Raised on a dairy farm near Green Bay, Wisconsin, Mike Hutjens was active in both 4-H and FFA. Named top graduating senior at the University of Wisconsin, he earned bachelors, masters, and doctoral degrees there, with the latter in dairy science and nutritional science. His graduate paper was awarded first place by the American Dairy Science Association. From 1971 to 1979, Dr. Hutjens was extension dairy specialist at the University of Minnesota. From that point forward, he held his extension dairy specialist position at the University of Illinois until retiring in 2010. He annually speaks at close to 40 meetings in the Midwest, and has spoken at conferences worldwide. He has authored hundreds of technical and popular articles, co-authored a text on dairy science, authored several Hoard Dairyman books, and is a regular columnist in Hoard’s Dairyman magazine. Dr. Hutjens has served as official judge for the Hoard’s Dairyman Cow Judging Contest, at World Dairy Expo, and at 16 state fairs. Award recognitions include: • ADSA DeLaval Extension Worker Award • ADSA Applied Nutrition Award (1992) • Young Midwest Regional Young Extension Award (sponsored by ASAS) • Paul A. Funk Outstanding Faculty Award (College of Agriculture) • Outstanding Extramural Instructor (University of Illinois award) • Two citations from the Minnesota Board of Regents • PDCA Dairy Person of the Year (Illinois Milk Producers Association) • Minnesota Holstein Association’s Person of the Year Award • ADSA awarded him the Purina Mills Undergraduate Teacher award (2007) • World Dairy Expo’s Service Person of the Year (2008) • Honorary State Farmer Award from Illinois FFA (2011) • Honorary Member of the American Association of Bovine Practitioner (AABP) (2011) • “Eagle Award” for service excellency from the Illinois Farm Bureau Association (2011) • National DHI Service Award in Florida (2013) • ADSA Award of Honor and ADSA Fellow (2013) • ADSA Distinguished Service Award (2016) He was elected to serve as vice-president, followed by the presidency, of American Dairy Science Association (ADSA) in 2003-2005. Dr. Hutjens resides in Savoy, Illinois, with his wife Carol, three sons, two daughters, and seven grandchildren.
Dedication
Hoard’s Dairyman has offered a book on feeding to its readers for over 80 years. In a 1936 edition, feeding information was provided for poultry, horses and swine, along with dairy cattle. Of course, much has changed in animal nutrition since then. The editors of Hoard’s Dairyman magazine who authored previous editions, as well as the columnists who guided the three most recent editions, have endeavored to provide the very latest and best information on feeding dairy animals. In this 4th edition, following the tradition of our 1998, 2003, and 2008 editions, we remember and pay tribute to the efforts of two former columnists: the late James Crowley, leading authority on dairy cattle feeding with the University of Wisconsin Extension, and the late Marshall E. McCullough, consulting nutritionist and emeritus professor of animal nutrition at the University of Georgia.
© 2018 Copyright by W.D. Hoard & Sons Company All rights reserved. No part of this book may be reproduced or used in any form or by any means, electronic or mechanical, including photocopying, recording or by an information or storage retrieval system, without permission in writing from the publisher. Address inquiries to: W.D. Hoard & Sons Company Book Department P.O. Box 801 Fort Atkinson, WI 53538-0801 USA www.hoards.com Tel: 920-563-5551 Printed in the United States of America ISBN 978-0-932147-60-8 (print) | ISBN 978-0-932147-61-5 (ebook) Library of Congress Control Number: 2018905486 Special thanks: Book design by Aisha Liebenow Special Publications Manager Hoard’s Dairyman Digital book production by James Baltz Instructional Design Specialist University of Illinois
Contents .......................................................................................................................... 7 Chapter 1. Feeding a ruminant: dairy cow physiology .................................................................... 8 Chapter 2. Feed nutrients ....................................................................................................... 15 Chapter 3. Optimizing dry matter intake .................................................................................. 27 Chapter 4. The gestation-lactation cycle ................................................................................... 31 Chapter 5: Feeds for dairy cattle ............................................................................................. 40 Chapter 6: Feeding systems .................................................................................................... 52 Chapter 7: Ration formulation ................................................................................................ 58 Chapter 8: Purchasing and valuing feed ................................................................................... 65 Chapter 9: Feeding disorders ................................................................................................. 70 Chapter 10: Calf feeding guidelines ......................................................................................... 75 Chapter 11: Heifer feeding systems ........................................................................................... 81 Chapter 12: Dry cow management ........................................................................................... 85 Chapter 13: Special feeding challenges ..................................................................................... 88 Chapter 14: Using Dairy NRC 2001 ......................................................................................... 93 Appendix tables .................................................................................................................. 96 Introduction
6
Introduction
T
hree factors determine the amount of milk a cow produces: 1.
Genetics
2. Management and environment conditions 3. Feeding program
The number of dairy cows needed to feed the world has declined along with the number of dairy farmers. This is largely due to the incredible success of dairy farmers’ and researchers’ combined efforts to maximize dairy cow production by improving the above three factors. In the U.S. from 1985 to 2017, the number of dairy cows declined from 10.9 million to 9.39 million. Meanwhile, the average milk yield increased over 74 percent, from 13,024 pounds (5,908 kilograms) to 22,942 pounds (10,406 kilograms); and total milk production increased to 212 billion pounds (96.2 billion kilograms). At the same time, the U.S. farm prices were below $12.76 in 1985 while they sat below $16 in 2018. After this book goes to press, prices very well could hit $18 – but there are no guarantees. This story is not over, as the world record cow recently produced over 78,000 pounds (35,380 kilograms) of milk in one year. Herd averages exceeding 30,000 pounds (13,608 kilograms) of milk per cow is common, with elite herds averaging over 35,000 pounds (15,876 kilograms) of milk per cow. Genetic technology (cloning, embryo transfer, and sexing semen), improving the cow’s environment (heat stress reduction and vaccines), computer aids, and feeding improvements (amino acid balancing and rumen manipulation) will continue to “raise the production bar”. This book will address the feeding factor of the production equation and provide practical feeding guidelines and recommendations to increase the profitability of the dairy farm. Dairying can no longer be considered just a way of life; it is a highly competitive business. There will always be a dairy industry – the question is who will compete and survive.
Mike Hutjens June, 2018
7
Chapter 5. Feeds for cattle
F
eeds are generally classified as forages, concentrates, or supplements. Let’s look at these classifications. 1.
Forages (also called roughage): Feeds over 20 percent acid detergent fiber (ADF) (18 percent crude fiber) and less than 0.7 Mcal NE-l per pound of dry matter (1.54 Mcal NE-l per kilogram)
2. Grains: Feeds under 20 percent ADF and over 0.7 Mcal NE-l per pound (1.54 Mcal per kilogram) of dry matter 3. By-products: feedstuffs from which some nutrients are removed (such as sugar, starch or oil) for human use and which have nutrients remaining for dairy cattle 4. Protein supplements: Feeds over 25 percent crude protein 5. Additives: feedstuffs added to a ration for a non-nutritive reason, such as rumen buffer, ketosis control, or rumen digestion improvement 6. Mineral supplements: Feeds over 75 percent ash or mineral (see Chapter 2) 7. Fat supplements: Feeds over 20 percent fat/oil (see Chapter 2)
Forages
The vegetative part of the growing plant, forages are more fibrous and bulky. These feeds are lower in energy and stimulate rumen digestion and fermentation. Forages can be harvested, stored, and fed in different forms. Hay is forage that has been allowed to dry down to be stored as a dry feed. Conventional square baled hay should be less than 22 percent moisture to avoid molding and heating. Large round or square bales need to be less than 20 percent moisture. Their smaller surface area and greater forage weight per bale mean they are more prone to heat and mold during the curing process. If hay is too wet, adding propionic acid or salts of propionic acids can minimize molding. Table 5.1 lists losses associated with forage harvest and feeding.
40 CHAPTER 5. FEEDS FOR CATTLE
Hay silage is forage that is wilted, or dried down, to a higher moisture level than dry hay and allowed to ferment in storage. Fermentation produces organic acids (primarily lactic acid), which drops the pH below 4.5 and “pickles” or preserves the forage. The level of dry matter in silage depends on the type of silage and storage method: • Conventional upright silos, oxygen limiting: 50 to 60 percent dry matter • Conventional upright silo, concrete or stave: 40 to 50 percent dry matter • Bags, bunkers, and piles: 35 to 45 percent dry matter Corn silage is typically ensiled at 30 to 38 percent dry matter. Typical losses are listed in Table 5.1. Green chop is directly harvested as standing forage and fed fresh to animals. No wilting occurs, which avoids harvest and weather damage losses. However, forage quality is changing daily, and weather can limit when harvesting can occur. Direct-cut forages can contain over 80 percent moisture.
Alfalfa with less lignin Two technologies are commercially available to dairy farmers to produce alfalfa with less lignin; conventional genetic breeding-based alfalfa and genetically-modified alfalfa. Depending on the type and variety, lignin content is reduced by 7 to 15 percent. This allows for higher digestible alfalfa if cut at similar times compared to conventional alfalfa. If harvest is delayed by five to seven days on lower lignin varieties, tonnage improves while quality is maintained compared to traditional alfalfa varieties. Lodging and yields are similar to traditional alfalfa varieties, depending on the strategy used (targeting more quality or more yield). The seed cost by weight will be higher.
Table 5.1 Dry matter losses in forage harvest and storage Dry matter losses Method Harvest (%)
Storage (%)
Total (%)
Rained on
33
4
37
Average
25
4
29
No rain
17
4
21
Field cured
25
14
39
Acid treatment
15
11
26
Heat dried
13
2
15
70 or more
2
21
23
60-69
5
10
15
Under 60
12
8
20
70 or more
4
13
7
60-69
5
6
11
Under 60
16
6
23
Hay Conventional bale, field cured
Large packages Conventional bale Hay-crop silage Moisture % Corn silage
Moisture %
Source: Pennsylvania Extension Special Circular 223 CHAPTER 5. FEEDS FOR CATTLE
41
Pasture allows animals to harvest forage directly, eliminating harvesting time, expenses, and manure handling. Trampling can be a problem, resulting in losses of 30 to 60 percent of the available dry matter. Forage quality changes daily and must be managed as well. Several pasture systems can be used: • Rotational grazing: Two to four paddocks are rotated every week to 10 days. Forage quality, plant selection, and trampling are difficult to control while labor is minimal. • Strip grazing: An electric wire is moved every day or 12 hours, allowing the desired amount of pasture to be consumed. Feed control is excellent, but this method requires more labor and management. • Intensified grazing: Numerous paddocks (10 to 30) are rotated to maintain pasture quality and avoid trampling. A paddock is pastured for 12 hours to two days, with milking cows consuming the new forage and dry cows and/or heifers following to finish harvesting the paddock. In spring, several paddocks are harvested to develop a staggered growth pattern and provide stored winter feed. Pastures are initially grazed at 8 to 10 inches (20.3 to 25.4 centimeters) of length down to 4 inches (10.2 centimeters). The remaining 4 inches (10.2 centimeters) of pasture allows plants to regrow while maintaining forage quality. The following forages can be fed to dairy cattle. Their nutrient compositions are listed in Appendix Table 4. Legumes such as alfalfa, clover, soybeans, and birdsfoot trefoil are excellent sources of crude protein, calcium, and minerals. Because of a tap root system, legumes can tolerate dry conditions. Winterkill can be a problem if freezing and thawing occurs in northern regions.
Grasses, such as rye, fescue, timothy, brome, orchard, and warm-season grasses such as bermuda, are low in calcium, protein, energy, and lignin. The root system is shallow and may become dormant during hot, dry weather. Winterkill is less of a problem than with legumes, and grasses can survive grazing conditions more effectively compared to legumes. Corn silage contains 40 to 55 percent grain on a dry matter basis. The forage is high in energy, palatability, and dry matter yield (6 to 10 tons per acre [13 to 22 metric tons per hectare]). Crude protein, calcium, and other minerals are low compared to legumes. Brown midrib (BMR) corn silage is lower in lignin content (reduced 30 to 50 percent), higher in digestible neutral detergent fiber (NDF), leading to higher milk yield. Yield of corn silage per acre may be reduced 10 percent. Sorghum can be used for silage in areas where dry weather can limit corn silage yield. Sorghum silage is lower in quality and dry matter intake potential compared to corn silage. BMR sorghum (lower in lignin) is also available and recommended for lactating dairy cows for improving fiber digestibility and increasing milk yield. Small grain forages (such as oats, barley, wheat, rye, and triticale) are annual crops that can provide an early source of forage. Winter small grain forages allow double cropping, a source of pasture, and soil cover during the winter. Spring small grain forages can be used as a cover or nurse crop to establish legume-grass forage. For dairy cows, small grain forage should be harvested in the boot stage for higher protein and energy content. If harvested in the milk to dough stage, dry matter yield can double, but protein and energy levels drop dramatically. Peas and bean seed can be planted with small grains to increase protein content and quality. Small grain forages are difficult to make into hay because of high-moisture content when harvested in the boot stage. Small grain forages can be planted in fall after corn silage removal to get a late fall crop as silage if moisture and temperatures are favorable. Straw (oats, barley, wheat, and corn stover) is low in protein and energy content. Mineral levels are also low, requiring higher mineral supplementation. The amount of straw should be limited because of its low quality and slow rate of passage. Straw can provide functional fiber, however, and cows may crave it in the case of rumen acidosis.
Grains
The seed portion of a plant is considered grain. Grains contribute energy to the ration along with variable amounts of oil, protein, and minerals. Grain should be processed to break the seed coat. If grain particle size is too coarse, digestion is reduced and undigested grain appears in the manure. If feed is processed too finely, rumen acidosis and laminitis can occur. The optimal particle size of grain will depend on whether a total mixed ration is fed, forage particle size, and the level of grain fed. The following grains can be fed to dairy cattle depending on soil type, climate and growing conditions. Feed values are listed in Appendix Table 5.
A cow grazing on its pasture-provided meal.
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CHAPTER 5. FEEDS FOR CATTLE
Kernel and shredlage processing Plant processing of corn silage, also called kernel processing, is a useful technology. New corn silage choppers have two added rollers with 1- to 2-millimeter adjustable openings that run at different speeds, rolling corn silage after it is chopped and before it’s blown into the wagon or truck. Particularly for latechopped corn silage, this process breaks the kernel, which lowers whole seed passage and loss in the manure. It also reduces the cob to pea size, making it more difficult for the cows to sort out. And by shredding the cornstalk, fiber digestibility increases. Milk production increases vary from 1 to 3 pounds (0.45 to 1.4 kilograms) more milk per cow per day. This technology allows longer chop length (3/4 inch [2 centi-
meters] theoretical length of cut [TLC]), resulting in more functional fiber. The added economic benefits are $3 to $4 per ton, while custom operators typically charge an extra $1 per ton for processing, due to the cost of added rollers and power required. Shredlage is a new technology with various types of rollers that can crush the kernel more completely. The initial cost of these new rollers is two to three times higher. Most custom operators and dairy farmers will chop the shredlage longer at 1 to 1Âź inch (25 to 28 millimeters) TLC resulting in an increase to 30 percentage wet silage in the top box of the Penn State box compared to 10 to 15 percent with kernel processed corn silage at 3/4 inch (18 millimeters) TLC. Custom operators may charge $1 to $2 more than kernel processing due to addition fuel and initial cost of the rollers.
CHAPTER 5. FEEDS FOR CATTLE
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Barley is a good source of energy and protein. It can make up to 100 percent of the grain mixture, but it must not be ground too finely. Barley starch is rapidly degraded in the rumen due to its starch structure. Adding 25 to 50 percent to the grain mixture is recommended if it is economical. Ear corn, or corn and cob meal consists of the cob (20 percent) and grain portions (80 percent). It is relatively high in energy, palatability, and contains fiber, helping to reduce acidosis. The cob should be processed to pea size to avoid sorting by the cow. A common ratio is 50 percent ear corn and 50 percent shelled corn in the Midwest. Adjusting combines to save half of the cob allows more rapid harvest compared to corn pickers. Shelled corn is the most common grain in the North American continent because of its high yield and energy content, as well as its use as an economical source of energy. It must be processed to avoid whole seed passage through the digestive tract. Corn (shelled or ear) harvested as high-moisture corn (25 to 35 percent moisture) has several advantages: • • • • •
Two to three weeks earlier harvest Less field loss Fits automated feeding systems No drying costs Increased palatability
• Higher energy content on a dry matter basis If wet corn is stored in conventional silos, bags or bunkers, the corn should be processed as its put into storage to improve fermentation and lower air entrapment. Propionic acid can be used to “pickle” wet corn to prevent molding and maintain quality. Oats are 15 percent lower in energy compared to shelled corn. Their popularity has declined due to lower yield (compared to corn or barley) and higher cost per pound. Oats add bulk and fiber to the grain mix. Limit the amount to 25 to 33 percent of the grain mix. Sorghum grain or milo can be used to replace corn. The energy content is 90 percent of corn and the grain must be processed. The small round seed will pass through the cow’s digestive tract if the seed coat is not broken. Wheat is not commonly used in dairy rations because the cost is higher than corn, barley or oats. If used, limit the amount to less than 50 percent in the grain mixture as wheat is rapidly fermented. Wheat must be processed prior to feeding to avoid whole seed passage. Rye is another small grain crop that is similar to oats. It is less palatable and should be limited to 25 percent of the grain mixture.
By-product feeds
By-product or co-product feeds are produced when a portion of the feed is removed for human consumption or use (such as ethanol production). By-product feeds may be higher in protein, fat, and/ or mineral compared to the original grain. Nutrient composition of by-product feeds is listed in Appendix Table 6. Almond hulls are the outer covering on the almond shell with the almond seed inside. The hulls contain 4.2 percent crude protein and 32 percent NDF with 0.70 Mcal of NE-l per pound of dry matter
44 CHAPTER 5. FEEDS FOR CATTLE
(1.52 Mcal NE-l per kilogram). Almond hulls are not palatable and should be limited to 5 to 6 pounds (2.3 to 2.7 kilograms) per head per day. Beet pulp is produced when sugar is removed from sugar beets. Beet pulp can be fed as wet or dry forms, and with or without added beet molasses. The dry form can be fed in pellet or shredded forms. Beet pulp is high in pectin, which is rapidly fermented in the rumen. Limit the amount to 33 percent of the grain mixture. Cottonseed is usually fed whole with fuzz or linters attached. The fuzzy seed contributes to the fiber mat in the rumen and is high in oil, protein, and fiber. Delinted cottonseed (no linters) is fed because of improved handling and flow characteristics. Limit the amount to 5 to 7 pounds (2.3 to 3.2 kilograms) per cow. Acid delinted seeds should not be fed. Corn gluten feed is popular in the Midwest, a by-product of corn starch and corn syrup used for human food and fuel. The feed
Grain processing Types of mechanical changes: • Dehulling removes outside seed coat • Extruding forces seed through a small die, generating heat • Grinding reduces grain particle size with a hammer mill • Dry rolling cracks or crushes the seed to flat particles • Crimping or steam rolling involves steam treatment following rolling Types of heat treatment: • Micronizing is dry heating by microwaves from infrared burners • Popping is exploding or puffing grain due to rapid heating • Roasting heats and tempers grain to improve nutrient availability • Exploding swells grain by putting it under pressure, then releasing it to the air • Flaking improves nutrient availability by starch gelatinization through modified steam rolling • Pelleting forces finely ground feed through a die to shape for easier handling • Crumbling further processes the pellets through crushing Types of moisture treatment: • Drying removes moisture for proper storage and to avoid heating • High-moisture grain is harvested early as immature seed • Reconstituted grain is dry grain with moisture added followed by storage to improve digestion • Soaking involves adding water several hours before feeding to soften feed or lower the dust level
is produced from wet milling of corn. It is low in oil, high in digestible fiber, and moderate in protein. It can make up 50 percent of the grain mixture. Hominy feed comes from the manufacture of pearl hominy, hominy grits, or table meal from corn. Similar in appearance to ground corn, it has slightly more energy and protein, and similar feeding characteristics. Hominy should be analyzed for its fat content, which can vary considerably due to the type of manufacturing process. As fat content drops, so does TDN. Hominy is palatable and can be included in the grain mixture at high levels. Molasses (cane and beet) supplies energy while improving palatability. The wet form is more effective in reducing dustiness and minimizing grain fines. Limit the amount to 5 to 7 percent of the grain mixture. Higher levels of liquid molasses can affect feed flow (sticky) and lower rumen digestion of fiber and pH. Screenings are produced when seeds are screened to remove broken kernels, fines, and weed seeds. These products can be economical but variable in nutrient content. Mycotoxins can be concentrated in this fraction if seed damage has occurred. Whole weed seeds may pass through the animal’s digestive tract, causing weeds to emerge in clean fields. Soybean hulls or soybean flakes are an excellent source of digestible fiber and energy. Limit the amount to 33 percent of the grain mixture. Wheat mill run feed can contain wheat bran, midds, germ, and/or shorts, which are bulky and moderately high in digestible fiber. Limit the amount to 20 percent of the grain mixture. Whey (dried or liquid) can be fed to dairy cattle. Dried whey can be added to the grain mix up to 10 percent if economical. Adding 20 to 50 pounds (9.1 to 22.7 kilograms) of dry whey to a ton of wet silage can stimulate bacterial growth and acid production. Liquid whey can contain 94 percent moisture, depending on the process and concentrating method. Fresh whey should be discarded after 24 hours because it will become acidic and affect teeth. Offer both whey and water at all times. Introduce liquid whey gradually to dairy cattle to avoid overconsumption, bloat, and rumen acidosis. Flies are also attracted to liquid whey. Another whey by-product available in some areas is condensed whey solubles, which contains 25 to 35 percent dry matter (limit the amount to 3 pounds (1.4 kilograms) of dry matter per cow per day.
Snaplage Snaplage is a high-moisture corn product increasing in popularity because commercial field choppers can be used with a snapper head to harvest the corn crop six or more rows at a time (fast harvest potential). Because of kernel processors in the field chopper, snaplage is processed in the field before going into storage and ready to feed. Snaplage consists of the kernel, cob, husk, and some upper plant parts. The starch content ranges from 50 to 60 percent (high-moisture shelled corn is over 70 percent starch). Harvesting corn grain occurs earlier when the corn kernel has developed the black layer at the base of the corn kernel indicating maximum starch accumulation has occurred. Snaplage typically contains 40 to 45 percent moisture, which results in improved compaction and fermentation (over 40 percent moisture is recommended). A recommended silage inoculant should be added at ensiling. Dairy farmers and nutritionists may need to add 2 to 5 pounds (0.9 to 2.3 kilograms) of dry shelled corn to the ration to reach optimum starch levels and slow the rate of starch fermentation.
Protein supplements
Bloodmeal is dried blood from slaughtered animals. Spraydried bloodmeal is superior to ring-dried because less heat damage occurs. It is high in rumen undegraded protein (RUP) and lysine. Limit the amount to 1/2 to 1 pound (0.23 to 0.45 kilogram) per day to avoid reducing dry matter intake. Brewers grains are produced from brewing beer. Wet brewers grain can vary from 70 to 80 percent moisture and should be evaluated on a dry matter basis. If the wet form is fed in summer, it should be bagged or fed in four to seven days to avoid molding, deterioration, and lower feed intake. Dry brewers grains are a good source of RUP but dusty to handle. Brewers grains can be incorporated up to 25 percent of the total ration dry matter. Avoid rations containing more than 55 to 60 percent moisture.
A handful of almond hulls. CHAPTER 5. FEEDS FOR CATTLE
45