Normal Biological Growth of Dairy Calves

Dr. Ronald L. Boman
USU Extension Dairy Specialist

In the January USU Dairy Newsletter I summarized parts of a presentation to the Utah dairy producers by Dr. Michael Van Amburgh from Cornell University concerning what many are referring to as �Accelerated Growth� of dairy calves. Actually what people today are calling accelerated growth is really �Normal Biological Growth� of dairy calves. This so-called accelerated growth is not �fattening.� It is more like the growth that we see in beef calves, lambs, and piglets that are nursing their mothers. The reasons for wanting to obtain this Normal Biological Growth is to decrease age at first calving, decrease the incidence of disease and death loss, and increase the milk production potential of these calves. I�ve been receiving a number of inquiries about where to purchase the higher protein milk replacers, about the suggested feeding program and how long to feed this milk replacer, and how to manage these calves after weaning, etc.

Sources for higher protein milk replacers

Two companies that I�m aware of that supply the higher protein milk replacer to the Intermountain West are Land O� Lakes and Milk Specialties. In Utah and Southeastern Idaho, Intermountain Farmers Association has joined with Land O� Lakes to provide a higher protein milk replacer to dairy producers. There may be others that are providing this higher protein milk replacer, but I�m not aware of them presently. I SHOULD ADD RIGHT NOW THAT THIS HIGHER PROTEIN MILK REPLACER IS NOT A SILVER BULLET TO SOLVE ALL DAIRY CALF REARING PROBLEMS. These higher protein milk replacers are intended to be fed at higher rates than we have been accustomed to. We still have to pay attention to proven calf management practices and then continue the feeding and management through the various growth stages of the calf and heifer to avoid fattening.

Normal biological growth feeding schedules

1. Colostrum feeding period - It is essential that the calves receive one gallon of high quality first milking colostrum either bottle-fed or tubed immediately after birth. These new feeding recommendations also include colostrum 12 and 24 hours after the initial feeding. The importance of feeding high quality colostrum (especially in the first feeding) cannot be over emphasized. True colostrum (first milking) has up to twice as much total solids, five times as much protein and three times as many minerals as whole milk. It is also higher in energy, vitamins, and immunoglobulins (antibodies). These immunoglobulins from the colostrum are essential to the calf�s survival and subsequent performance.

2. Milk replacer feeding period - The old industry standard was to feed � lb of milk replacer powder in 4 quarts of warm water twice each day until the calf was eating about 2 lbs of calf starter and ready to be weaned. The NEW standard feeding practice for the first week is to feed 1.5% of the calf�s weight daily in milk replacer powder. For example, if the calf weighs 100 lbs, then it would get 1.5 lbs per day (100 X .015 = 1.5 lbs) of milk replacer powder. The dilution rate of powder in warm water is 15%. Therefore 1.5 lbs powder divided by 15% equals 10 lbs of warm water. Assuming twice a day feeding, the calf would get 3/4 lb of powder in 2.5 quarts of water each feeding. From the second week to week 5 or 6 of its life the calf would get 2.0% of its body weight in milk replacer powder (for simplicity, 110 lbs X .02 = 2.2 lbs of powder). The dilution rate is still 15%. Therefore 2.2 lbs divided by 15% equals approximately 15 lbs warm water. Assuming twice a day feeding, the calf would get 1.1 lbs of powder in 3.75 quarts of water each feeding. Notice that the dilution rate of 15% stays constant, so that the amount of milk replacer and warm water increase in the same proportion. Land O� Lakes, Milk Specialities, and Intermountain Farmers may have slight modifications of the procedure that I have described for their high protein milk replacers. If you follow their recommendations make sure that they indeed are the NEW feeding recommendations for the higher protein milk replacers.

3. Drinking water always available- Calves need free access to fresh drinking water to enhance dry starter consumption. With the higher protein milk replacers fed at higher rates, there is an additional need for the calf to have free access to water so the kidneys can eliminate the additional nitrogen (urea) associated with the higher dietary protein and the increased growth rate.

Weaning of normal biological growth calves

Calf starter is an integral part of this program. Dr. Van Amburgh recommends a high quality 26% protein starter. Begin feeding the starter at 3 or 4 days of life. Once the calves are averaging 2 lbs of starter over a 4 to 5 day period they can be weaned. It is suggested at this time to cut the volume of milk by � and to feed it only in the morning for one additional week. Be certain that calves have access to clean drinking water. Leave calves in their same pens for another week to ensure that they are consuming 5 to 6 lbs of calf starter. Two ounces of Yeast Culture added to the starter one week before and one week after weaning has been shown to increase starter consumption. After weaning, the calves should be moved into groups of 4 to 6 calves (depending on the numbers available) where they can be fed hay in addition to starter and water. These Normal Biological Growth calves at 6 to 7 weeks of age will be 30 to 35 lbs heavier, taller with a larger frame, healthier, and with better appetites than similar calves fed restricted amounts of lower protein milk replacer. At this point it is important to provide a ration balanced for protein and energy through the various stages of development to keep the heifer growing at Normal Biological Growth rates, to take advantage of the potential reduction in Age at First Calving and the increase in subsequent milk production. ©