Dairy calf nutrition:Milk feeding level, method, preservation, and weaning
Milk Feeding • At first digestive system is suited to digest only milk • As calf matures…system adapts to be able to digest solid feeds • First 2-3 weeks are critical for milk intake…very little, to no solid intake occurs • Maintain calves on whole milk or milk replacer (min 20% protein 15% fat) until 6-10 weeks of age
Milk Feeding Levels How much should we feed them? Need to consider what the calf is designed to do…
Milk Feeding • How much is being fed daily in Week 1?
Milk Feeding • How much is being fed daily in Week 4?
How much should we feed them? What does the cow do? • Nurses calf 5 - 10 times/d • Nursing bouts last 5 - 10 min • Provides about 10 kg of milk/d
How much should we feed them? What does the cow do? • Nurses calf 5 - 10 times/d • Nursing bouts last 5 - 10 min • Provides about 10 kg of milk/d What have we traditionally done? • Feed 2 times a day • Provide about 4-6 kg of fluid milk (whole or replacer)
Traditional milk feeding levels • Traditional calf management programs: • Emphasis on use of milk replacer powder containing 20% protein and 20% fat • Fed at rates of approx. 400 - 500 g/calf/day. • As a comparison, whole milk testing 3.5% fat and 3.0% protein would contain 27% fat and 24% protein (on an equivalent basis) • In many instances, particularly in Canada, this level of nutrition may not provide sufficient nutrients to meet maintenance requirements during cold weather.
Traditional milk feeding levels • Feeding programs based on feeding 500 g of milk (4L) or milk replacer DM day puts the calf at serious risk for limited or no growth during the first 2 - 3 weeks of life unless environmental conditions of temperature and moisture are optimal • Examples: • At 32°C, 454 g of a 20:20 milk replacer provides sufficient energy for 45 g gain, yet when temperature drops to zero calves will lose weight. • Similarly approximately 4L of whole milk does not provide enough nutrients for gain at 0°C.
Increased milk feeding levels for accelerated growth • Recommendation now is to feed calves more milk – increase rate of frame growth (not fattening per se) • Feed whole milk ad libitum (free access) or at other high levels (8-10+ L/day) • Feed more milk replacer • 1 to 1.5 kg of powder/day • 26-28% CP, 15-20% fat • Achieve gains of 1 to 1.5 kg/d of growth pre-weaning
Free Access Feeding of Milk to Calves 10 Calves will drink more milk when they are provided the opportunity 8 6 Milk consumed (kg/d) 4 Conventional 2 Ad libitum 0 0 2 4 Calf age (weeks) Jasper & Weary, 2002; J. Dairy Sci. 85: 3054-3058.
Free Access Feeding of Milk to Calves 90 Providing more milk allows for faster growth during the milk-feeding period… this advantage can be maintained through proper weaning weaning 80 70 60 Calf weight (kg) Conventional 50 Ad libitum 40 0 2 4 6 8 Jasper & Weary, 2002; J. Dairy Sci. 85: 3054-3058. Calf age (weeks)
Free Access Feeding of Milk to Calves Higher milk intake slows starter intake before weaning, but will not after weaning 3 Conventional Ad libitum 2 weaning Starter intake (kg/d) 1 0 0 2 4 6 8 Jasper & Weary, 2002; J. Dairy Sci. 85: 3054-3058. Calf age (weeks)
What milk feeding levels is required by and recommended to producers? • Requirement: calves must receive a volume…of milk or milk replacer to maintain health, growth and vigor. • Recommended best practice: offer calves…20% of body weight…until 28d…(approx 8L/d for a Holstein)
Higher growth rates during the milk-feeding phase have long-term benefits! • Great weight at calving • increased weight gain during the first 2 mo of life results in significantly greater body weight at 24 mo of age (Moallem et al. 2010. J. Dairy Sci. 93:2639-2650) • Survivability • Heifers that reached second lactation grew more between 12 and 65 d of age than those that did not (Bach. 2011. J. Dairy Sci. 94:1052-1057)
Feeding more milk increases milk production later in life!! • Study Response__ • Soberonet al. 2009 1061 kg (1st lactation) 616 kg (2ndlactation) • Bar-Peledet al., 1998 454 kg • Foldagerand Krohn, 1994 1403 kg • Foldageret al., 1997 518 kg • These responses were achieved by increasing pre-weaning milk intake by at least 75% over conventional intake
How do we maintain Milk Quality? • Feeding higher levels of milk increases the risk of bacterial growth in milk available to calves throughout the day • Milk quality should be maintained: • Use robotic calf feeder which mixes milk at each feeding • Pasteurization • Limit time availability • Acidification
How do we maintain Milk Quality? • Pasteurization • Reduce disease-causing bacteria • Need constant supply of non-saleable milk and/or use saleable milk
How do we maintain Milk Quality? 4h/d • Limit time availability? • Providing access to ad libitum milk for 4 h/d vs. 24 h/d has no detrimental effects on intake 24h/d 10 Min / h 7.5 5 Time on teat 2.5 0 0 6 12 18 24 von Keyserlingk et al., 2006. J. Dairy Sci. 89:2126-2131
How to maintain Milk Quality? • Acidification? • Preserve milk with formic acid • Acidification with formic acid preserves milk for storage at room temperature and allows batch mixing at 1-to 3-day intervals to save labour • In addition, the milk is fed cool to avoid gorge feeding
How to maintain Milk Quality? • Acidification to pH 4.0 -4.5 is to preserve the milk/milk replacer • Once preserved from growth of bacteria and molds, the milk can be stored at room temperature for several days • Proper preservation permits free-access feeding of milk to calves without the need for refrigeration of the milk • Acidification decreases a calf’s exposure to bacteria because it decreases the bacterial load in milk or milk replacer
How to maintain Milk Quality? • Timely stirring of acidified milk assures calves receive a consistent mix when they suckle • Since acidified milk gels and separates, timely stirring is essential • Vigorous stirring at high rpm for a short duration will achieve excellent mixing
How to maintain Milk Quality? • Least expensive equipment includes: • Electric drill and paint mixer attachment to mix the milk and preservative • Container to hold a reservoir of milk • Teats on the container or attached to a feeder bar on a wall • System may be gravity fed with teats at the bottom of the container or line-fed with teats attached to a plastic line with a one-way valve
How to maintain Milk Quality? • Free-access feeding systems can be automated with mixers on timers or recirculation pumps to deliver milk from one reservoir to several groups of calves and back to the reservoir • In general, acidified milk may be prepared at 1-3 day intervals and the equipment cleaned 2x per week • The use of a preservative (acidification to pH 4.0 -4.5) and feeding at a cool (20°C in winter) temperature (to limit intake per meal) are essential to the success of free-access feeding systems
For further information on acidified milk feeding: See notes by Dr. Neil Anderson for instructions: • http://www.omafra.gov.on.ca/english/livestock/dairy/facts/mimick.htm
How should we provide milk to calves? • By bucket? • During each feeding calves spend on average 44 s drinking milk, and 6 min sucking on the empty bucket Appleby et al., 2001. Appl. Anim. Behav. Sci.74:191-201
How should we provide milk to calves? • By teat? • When provided free access, calves spend on average 47 min drinking milk, and typically spread this feeding time into 6 to 10 milk meals. • Teat feeding also increases insulin and CCK levels (good for digestion!) Appleby et al., 2001. Appl. Anim. Behav. Sci.74:191-201
Which way of providing milk is recommended? Recommended best practice: - provide milk via a teat or provide a dry teat after milk feeding to satisfy the calf’s motivation to suck
Feeding milk to calves in groups • Group housing and feeding is possible when calves are fed: • Free access (ad libitum) through a teat system • Using an automated calf feeder
Does group housing not increase the risk of cross sucking? • Cross-sucking is very rare among teat-fed calves (less than 0.2% of time) when provided sufficient amounts of milk Chua et. al. 2002. J. Dairy Sci. 83:360-364.
Group housing of calves also helps make calves more successful transitions at weaning • Pair housed calves fed ad libitum via a teat showed • similar weight gains to individually housed calves • show less of a growth check at weaning 1.0 Weight gain (kg/d) 0.5 Single Pair 0 2 4 6 8 Calf age (weeks) Chua et. al. 2002. J. Dairy Sci. 83:360-364.
How does milk feeding level affect solid feed consumption and weaning? • For calves with higher milk solids intake it is not unusual for calves to begin consuming calf starter until after the second week • Lower starter intake may slow the rate of rumen development, which has been assumed to contribute to calves "stalling out” (having a growth check) when weaned from milk
Weaning – Survey Results • How are calves weaned off milk? • Abruptly stop feeding 22% (191/849) • Decrease volume 29% (249/849) • Dilution of milk 37% (311/849) • Intermittent feeding 12% (98/849) • Combination of methods 93 • How is the time of weaning decided? • Calf age 812 • Calf weight 293 • Starter/grain intake 454 *often this is a combination*
Weaning Age – Survey Results • 5 weeks or less 2.4% (21/863) • 6 weeks 12% (101/863) • 7 weeks 9% (77/863) • 8 weeks 36% (311/863) • 9 weeks 10% (86/863) • 10 weeks or more 31% (267/863)
How best to wean calves fed higher levels of milk? 90 • Conventional • ‘Cold turkey’ • Simply remove milk • Too much of a growth check at weaning weaning 80 70 Calf weight (kg) 60 50 40 0 2 4 6 8 Calf age (weeks)
Calves used to consuming high quantities of milk are typically not consuming sufficient dry feed at weaning to maintain growth • Conventional ‘cold turkey’ weaning is NOT appropriate • Solid feed intake needs to be encouraged in the 1-2 weeks prior to weaning • Milk needs to either be: • Diluted • Reduced in amount
Recent research comparing weaning calves fed and weaned conventionally to those fed a higher milk level and stepped down Khan et al., 2007. J. of Dairy Sci. 90:3376-3387
Solid feed (calf starter) intake increased before and after weaning in calves fed through step down method Khan et al., 2007. J. of Dairy Sci. 90:3376-3387
Improved weight gains were observed in calves fed through step down method…NO growth check! Khan et al., 2007. J. of Dairy Sci. 90:3376-3387
Take Home Messages • Providing milk in sufficient quantities to maintain health and growth is key to long-term calf health, welfare, and productivity • Feed calves minimum of 20% of body weight in first 4 weeks of life • Providing milk by a teat is the most appropriate method of milk delivery • Milk quality is important and needs to be maintained to prevent bacterial growth • Calves should be weaned off milk gradually to ensure proper transition to solid feed