Sida 1 av 12 Op mizing ruminal fermenta on and health are priority challenges to every dairy nutri onist. With the fermenta on process in mind and the limited capacity of the rumen it s obvious that cows ea ng too much of low or slowly diges ble feedstuffs will meet limita ons in nutrient supply and on the other side excessive inges on of rapidly fermentable feedstuffs or feedstuffs providing unbalanced fermenta on products for the metabolism of the cows can upset rumen func on or the nutrient efficiency. With high gene c merit dairy cows both under- and overnutri on can have dire consequences for produc vity, efficiency, and health implying that high precision in feeding the rumen a substrate with constant composi on and proper es is mandatory to op mize produc vity, efficiency, and health. Classically dairy nutri on research has focused on predic ng the composi on of the op mum ra on and evalua ng feedstuffs for the op miza on of this ideal ra on. Most o en research has been done in confined environments with limited disturbance from feed bunk dynamics. Under prac cal condi ons many factors contribute to the complexity of rela ng nutri on to produc on results and health and one factor of major importance is behavior of cows at the feed bunk. From Danish experience it appears that introduc on of feed mixers in the dairy industry have been done with only a very li le systema c research into the mixing process and taking for granted that the concerns that predominated in the area of separate feed alloca on would also be the primary concerns in the TMR area. With the Compact TMR perspec ve on dairy nutri on it appears that we for years have underes mated the poten al in op mizing TMR for dairy cows. Essentials of the Compact TMR concept Compact TMR is a mixing concept that targets nutri on and behavior of dairy cows with the aim to simultaneously benefit produc vity, efficiency and health. The basic principle is that all cows in a feeding group/herd shall have unlimited access to a feed mix that cannot be sorted and therefore guaran es constant composi on of the substrate supply of the rumen and minimizes the struggle by cows for access to feed and eliminates the fight for the best feed. Nothing but the best feed is available to all cows all day. In prac ce the concept relies on: 1. Securing orts equivalent to minimum 2% of amount fed (approx. 1 kg/cow per day) 2. Providing the mix as Compact TMR Orts: Maintaining 2% orts (le overs) it cri cal to ensure that all cows have access to sufficient feed. Access to a TMR/PMR with a constant composi on at all mes is important to reduce stress on cows in the herd/group. The residues are also a cri cal control point to test if the offered mix is sorted by the cows. Orts and feed mix fed have to be indis nguishable, if this is not the case, cows have sorted the ra on and first and last cow feeding at the feed bunk have been offered different ra ons. Always test orts for aerobic deteriora on, if orts tends to warm the feed mix is not stable and unstable ingredients has to be replaced or the mix has to be preserved with acids (e.g. propionic acid). Maintaining a sufficient amount of orts is cri cal to the behavior of cows, if cows rush to the feed bunk at feed out or push up of the feed, they are either underfed (i.e. orts too small) or the feed mix can be sorted. Mixing process: The mixing process is divided into three phases in standard ver cal- and horizontal auger mixers 1. Soaking phase 2. Structuring phase (middle-mix) 3. Final-mix Soaking phase: Pelleted concentrate and dry feed components are sources of noise and can induce extensive sor ng in TMR and PMR mixes. To avoid these problems dry components of ra ons have to been soaked in water or other feedstuffs with high moisture content to ensure that these components are retained in the TMR/PMR. The amount of water required depend on the ra on and on the DM of silages added to the mix. A good star ng point is to use equal amounts of water and dry feedstuffs. Most pellets will burst when soaked for 1 h, but more resistant pellets like pellets of sugar beet pulp require mul ple hours (8 12 h). Adding too li le water is a much more common problem than adding too much water. Weigh dry ingredients into mixer without mixing to increase weighing precision. Add water when opera ng the mixer to ensure good contact between water and dry ingredients and to avoid too much of the dry ingredients residing on the augers. Important: When adding water to TMR/PMR the water should be added to dry ingredients that absorb the water. Avoid adding water to silages as this will reduce stability. Be aware of risk for decreased stability of feed mixes when adding water. 68 Djurhälso- och U odringskonferensen 2015 Växa Sverige
Sida 2 av 12 Optimum dry matter concentration of TMR/PMR: Addi on of water can be necessary not only to dissolve pellets and help small components adhere to the mix, but also to ensure that the final mix obtains a high density. The overall aim is to ensure that small concentrate par cles adhere to larger fiber par cles and cannot be sorted out by the cows. It is recommended to plan for 36 to 38% DM in Compact TMR mixed using ver cal auger mixers. With horizontal auger mixers o en 39 to 40% DM is preferable to prevent the mixers from squeezing water out of the mix in the final phase. Feedstuffs like molasses, sugar beets, pulp, dis ller s grain etcetera can also provide humidity and decrease or replace addi on of water. Structuring phase: In the structuring phase the most fibrous components are adding the soaking mix and the mixer is operated for 15 to 20 min. The purpose of the structuring phase is threefold: stepwise mixing, adherence of concentrates to the skeleton of the mix and shredding fibers. The structuring phase ensures a stepwise mixing process that allow concentrates to mix well into the most fibrous components of the mix. The fibers are the skeleton of the mix and are supposed to carry all nutrients to the cow. To ensure sufficient mixing and adherence of small par cles the standard mixing me in the structuring phase is 15 to 20 min (typical 26-32 rpm in ver cal auger mixers). The mixing impact of different mixers varies with fabric and geometry as well as the botanical composi on of silages. Mixer mounted with auger share to ensure sufficient flow during mixing. Final-mix: The last ingredient to be added to the mixer is corn silage. The heavy mix of the structuring phase is dissolved by addi on of corn silage. Many mixers are challenged by the physical proper es of the mix in the final phase (especially ver cal auger mixers). It is very important to monitor the mixer when star ng a Compact TMR protocol and a large range of mixers need to modified with auger shares / other devices mounted on the augers to be able to mix a Compact TMR. The final mixing me is again 15 20 min with 26 32 rpm of augers (ver cal augers). Don t stop mixer: When mixing Danish-type ra ons it is strongly recommended not to stop the mixer between the structuring phase and the final-mix. The mix from the structuring phase is very heavy and compact. Also if in any way possible don t stop mixer before unloading. Multiple mixes per day: In larger herds with mul ple mixes per day the number of soaking events and/or structuring mixes should be minimized by producing a large soaking-mix and/or structuring mix and use these as pre-mixes in several final mixes. Critical to maintain flow in mixer: It is of cri cal importance to ensure that your mixer can handle compact feed mixes before implemen ng this praxis. It is of paramount importance to monitor the flow of feed in the mixer if not all feed in the mixer is mowing it can be very harmful to the cows. Adjustments of the base of the auger close the sides of the mixing chamber, posi ons, and length of knives/blades and/or adjustment of secondary arm at the base of the auger (if present on the par cular mixer) are measures that can be involved in op mizing the mixer for Compact TMR. Mixers of several makes failed to mix Compact TMR without adjustments, but it has been possible to modify all mixers (except for some totally worn out mixers) for Compact TMR. Eating behavior: To test the mixing protocol you should evaluate the mix fed to the cows, evaluate the flow in the feed mixer, however, you also need to monitor the behavior of cows feeding on the mix. When cows feed from the top you have mixed the ra on well. If cows are searching deep into the mix or feeding on the floor they are sor ng and the ra on is improperly mixed. If cows eat feed only from the top of the pile and don t push around with the feed you have come close to provide them a Compact TMR. Växa Sverige Djurhälso- och U odringskonferensen 2015 69
Sida 3 av 12 Results 2012 2013 2014: Results based on introduc on of the Compact TMR concept at Danish dairy farms in the period from 2012 2014 showed: Less me spend a the feed bunk, cows eat faster and sort less, giving more res ng me and more me in stalls Reduced stress on cows cows don t rush to the feed bunk at feed out or push up of feed Higher milk produc on short term +5%, long term larger increase, many herds 1500 to 2000 kg ECM/cow more. Less problems with overcondi oned cows because no cow can sort out an imbalanced ra on Higher feed efficiency probably from be er nutri on of cows with low rank in hierarchy and less sor ng by low producing cows Be er health, stronger hoofs Downsides: Have to make sure that cows can lay comfortable in stalls as they will spend more me here when they don t need to fight for the good ra on. 70 Djurhälso- och U odringskonferensen 2015 Växa Sverige
Sida 4 av 12 Compact TMR vertical auger mixer Times indicated for mixers opera ng at 26-32 rpm. Descrip on Time/ac on Soaking phase Pellets and commodi es are soaked in water to enable be er mixing. Standard concentrate pellets can be soaked in 1 h. Star ng point is dry components:water (1:1). Sugar beet pulp pellets needs more me 8-12 h and more water. Run mixer when adding water. Alterna ves to water Beets and other moist feedstuffs can replace water and enable good quali-ty TMR/ PMR. Le whole sugar beets cut in mixer with commodi es. Structuring All ingredients except for corn silage for Danish type ra ons. Restrictor plates are out. Mix 15-20 min Make sure mixer is filled to top of augers. Don t stop mixer! Final-mix Add corn silage as last ingredient. Mix 15-20 min Important that all feed is moving. At the feed bunk Don t stop mixer, but feed out immediately. Always minimum 2% orts. No grass clumps Homogeneous short par cles Heavy mix No sor ng Cows ea ng from top Växa Sverige Djurhälso- och U odringskonferensen 2015 71
Sida 5 av 12 72 Djurhälso- och U odringskonferensen 2015 Växa Sverige
Sida 6 av 12 Växa Sverige Djurhälso- och U odringskonferensen 2015 73
Sida 7 av 12 THE COMPACT TMR CONCEPT 74 Djurhälso- och U odringskonferensen 2015 Växa Sverige
Sida 8 av 12 Växa Sverige Djurhälso- och U odringskonferensen 2015 75
Sida 9 av 12 76 Djurhälso- och U odringskonferensen 2015 Växa Sverige
Sida 10 av 12 Växa Sverige Djurhälso- och U odringskonferensen 2015 77
Sida 11 av 12 78 Djurhälso- och U odringskonferensen 2015 Växa Sverige
! Sida 12 av 12 Frågor och egna erfarenheter? Vad tar jag med mig? Konsekvenser? Prak ska idéer? Vad gör jag konkret? Växa Sverige Djurhälso- och U odringskonferensen 2015 79