Milk Replacers: Consistency Matters! – Dr. Max Thornsberry, Milk Specialties Global Animal Nutrition

By Dr. Max Thornsberry, Milk Specialties Global Animal Nutrition
The goal in mixing calf milk replacer is to consistently feed the same concentration of properly mixed milk replacer each feeding.  It is also necessary to feed calves their milk replacer meals at consistent intervals; in other words, the same time each day, hopefully at least 10 to 12 hours after the last feeding.  By attending to details, calf performance is maximized and insult to the calf and its digestive tract is minimized.

Milk replacer mixing guidelines

Volume of 110°F water	Weight of milk replacer	Percent solids as fed
2 qt	10 oz	13%
1 gal	20 oz	13%
5 gal	100 oz (6.25 lb)	13%
25 gal	31 lb	13%
50 gal	62 lb	13%
75 gal	94 lb	13%
100 gal	125 lb	13%
125 gal	156 lb	13%

Tank calibration and concentration
Most bulk milk replacer mixing tanks are not well calibrated.  Many simply have the gallon marks molded into the side of the plastic tank, and often the total-gallons-of-water calibration is, at best, an estimation.

Measure 5 gallons of water, pour it into the tank, and see if it registers at the 5 gallon mark.  If it does not, add a full 5 gallons at a time, marking in some manner the level of the water, while the tank is parked and level.  If in doubt, simply add 1 pound of milk replacer powder per gallon of water.  This will approximate 11 to 12 percent solids and will be close enough for mass-mixing and feeding.

Do not add more powder to the water than indicated on the directions of the milk replacer, which should be listed on the bag or the feed tag attached to the bag.  If the milk replacer is mixed at too high of a concentration, the extra nutrients in the final mix will act as a laxative on the calf, causing the calves to exhibit diarrhea within a few hours of consumption.  A calf under three weeks of age is fragile and will not tolerate abuse of the digestive tract.

Water temperature
Make sure water temperature is accurately assessed.  Do not mix milk replacer powder from a fully agglomerated or partially agglomerated milk replacer into water that is above 110 to 115 degrees F.  Hotter water will cook the nutrients, damaging or destroying their digestibility for the calves.  Start with a tank half-full of 115 F water, add the total amount of milk replacer powder, and then agitate or mix to get the powder mixed with the water while adding cooler water to the total volume.  Attempt to obtain a final temperature of 100 degrees F.

A large volume of milk replacer mixed in this manner will not cool appreciably while feeding, even in cold weather, if the calves are fed within a 30-minute window.  Do not feed calves milk replacer mixture hotter than 101 degrees F and cooler than 90 degrees F or refusals may result.  Proper digestion and placement of milk replacer in the proper stomach is dependent upon feeding the milk replacer in the proper temperature range.