Calf Management - Birth to Weaning

Tim Brown

Tarleton State University, Department of Animal Sciences, Box 0070, Stephenville, TX, 76402 U.S.A.

Take Home Messages


Taking care of calves during the milk-feeding phase is possibly the most management intensive facet of the dairy operation. Unlike management of larger growing stock or milking cows, where management lapses can reduce growth rates or milk production, even small mistakes with the very young calf can cause death. Thus, just keeping the calf alive during the first few weeks of life is a goal that requires preparation and execution of specific management practices. Additionally, the health of the calf, the development of its digestive tract function, and growth and development of its body during this period will influence subsequent performance. The objectives of this paper are to discuss specific management practices that will help reduce death losses and optimize calf performance from birth through weaning. Specific areas of emphasis are:

Birthing and Care of the Newborn

Calves born to difficult births are less likely to survive the birthing process, and will suffer more diseases and setbacks during the early weeks of life. Therefore, making the birthing process easier will enhance our chances of raising a healthy calf. Management for successful births is actually cow management. Some specific practices that will help the cow deliver a live and healthy calf, and help reduce stress and exposure to disease are:

The use of artificial insemination and bulls with proven transmitting ability for production and type traits is the number one tool for genetic progress in the dairy herd. Of the proven bulls that are available to us, we have many with high reliability for a low percentage of difficult births in heifers. Although the use of calving ease bulls should not be a management "crutch" to compensate for poor growth and development of the replacement heifer, it is a means by which difficult births can be reduced in heifers. Generally, the use of bulls with calving ease scores of 8 (8% difficult births in heifers) or less will help reduce the incidence of difficult births, and will possibly get the young calf off to a better start. Dry calving areas, with protection from wind and severe cold, will help keep the calf from using valuable body energy reserves to keep warm during the first few hours after birth. An excellent video ("How to Save More Calves at Calving") on managing the birthing process has been produced by Beef Today and Elanco Animal Health (1).

Dairymen differ in their opinions on how long the calf should remain with the cow after birth. From the standpoints of immune system development, calf nutrition, and disease control, removing the calf from the cow before it has a chance to nurse can yield benefits. To realize these benefits, we must take control. Calves need to consume adequate colostrum (see later discussion on colostrum management) in order to establish immune system function. We can not be sure that they will do so by nursing the cow. As a matter of fact, with what we now know regarding the amount of colostrum that a newborn needs to consume, it is a safe bet that she will not nurse enough on her own. The nutritional aspects of adequate colostrum intake are also important, especially for calves born in cold weather. From the standpoint of disease management, we understand that calves can come into contact with several potential disease-causing organisms when they first attempt to nurse the cow. Scours-causing organisms such as E. coli and Salmonella spp. are found in the manure that may be present on the udder and underside of the cow. Additionally, cows infected with Johne's disease, coccidia, and cryptosporidia will shed the infectious organisms in their feces, and contact with these organisms in the early days of life is suspected to be the primary means of spreading them to the young calf.

Colostrum and Colostrum Management

Colostrum is the first product removed from the cow's mammary gland after birth of the calf. These first secretions are formed during late gestation, and are designed to provide nutrition and disease protection to the calf. Colostrum differs somewhat from regular milk in its nutrient content, but the most significant difference between milk and colostrum is that colostrum contains specific proteins (globulins and albumins, the "antibodies" or "immunogloblins") that are capable of protecting against disease if we can get them into the bloodstream of the calf.

Calves are born with no immunological protection against disease. There is no transfer of antibodies from the dam to the calf during development in the uterus or during birth. The calf depends on absorption of colostral antibodies from its intestine to provide it with disease protection during the first few weeks of life. The degree of protection that a calf receives from colostrum depends on the mass of immunoglobulins it absorbs - more immunoglobulins equal more disease resistance. Calves that absorb no colostral antibodies have little chance of surviving until weaning. There are management steps that we can take to help ensure that the calf acquires all of the "passive" immunity it needs from colostrum. These steps include:

The key factors that affect the success of colostrum management are time of feeding, quality of colostrum, and the volume fed. It is the actual mass of immunoglobulins delivered to the calf that is important, and a greater volume of poorer quality colostrum may be required to deliver the same immunity as a lesser volume of better quality colostrum. Having high quality colostrum available when the calf is born is essential. Waiting to milk colostrum from the cow at normal milking time may cause too much of a lapse between birth and colostrum feeding. That time lapse is critical. We must get the colostrum into the calf immediately after birth. We could avoid that time delay if we had some colostrum stored and ready to use. Colostrum can be stored conveniently for several days by simply refrigerating it. Simply warm it to body temperature to feed it. Colostrum can also be stored for several days by fermenting it, without loss of immunoglobulin activity. Colostrum can be frozen for up to six months and still provide adequate immunity if thawed properly. Frozen colostrum should be thawed in warm (not hot) water and warmed to body temperature for feeding. Do not use a microwave to thaw colostrum. Freezing the colostrum in single serve containers works best. Two-liter soft drink bottles are handy. "Zip Lock" bags also work well, and take a little less time to thaw, since they tend to freeze with a greater surface to volume ratio.

We can actually manage the cow to produce colostrum of better quality. Since the immunoglobulins in colostrum are produced by the cow in response to disease challenges or vaccines that she has received, we can add specific antibodies to the colostrum by the vaccines we use on the cow. Modern biotechnology is providing us with some wonderful new products. We now have vaccines for certain strains of E. coli, one of the major scours-causing bacteria. Similarly, there are now vaccines available against rota and corona viruses, which also cause scours when they infect calves. We can use these vaccines to make the cow create antibodies against these pathogenic organisms, and her colostrum will contain these antibodies. We also have available to us colostrum supplements, which are either antibodies or antisera against specific infectious organisms. We administer these products to the calf orally at the same time that we would administer colostrum, and they can help protect the calf against specific diseases when colostral protection is less than desired. Some of the diseases against which we can purchase protection are shown in Table 1.

The ingredients of colostrum supplements should be examined critically. Some of them actually contain immunoglobulins or antisera against the diseases listed in table 1, while others simply serve as nutritional supplements.

Table 1. Organisms against which there are vaccines for cows and colostrum supplements for calves.

Vaccines for cows

Colostrum supplements for calves

Infectious Bovine Rhinotracheitis

Bovine Rota-Coronavirus

Bovine Viral Diarrhea (BVD)

E. coli

Parainfluenza type 3 (PI-3)


Bovine Respiratory Syncitial Virus








E. coli


Rota virus


Corona virus


If the adequacy of colostrum management is uncertain, there is a way to check if calves are receiving sufficient immunoglobulins. Since the immunoglobulins are actually proteins, their presence in the blood measurably increases the protein content of the blood and blood serum. The amount of protein in the serum affects its "refractive index", or the way it bends light that passes through it. Consequently, a tool that measures this refractive index, called a "serum refractometer", can be used to roughly estimate serum protein levels (18). Calves that have absorbed adequate colostral immunoglobulins will give higher serum refractometer readings than will calves who have received volumes of colostrum that are too small, colostrum that is too low in immunoglobulin content, or colostrum that was fed too long after the calf was born. The procedure for using a serum refractometer for this application is simple, and is a cheap and easy way to check up on your colostrum management crew to see if they are doing their job. If you just raise a few calves each year, the serum refractometer is probably a tool you don't need. However, if you manage a large number of calves, and question the adequacy of colostrum management, this tool can be a great way to not only check on your colostrum managers, but also to help them stay focused on the importance of colostrum management.


There are various ways to dehorn calves, and probably the most widely used are the Barnes dehorner and electrical dehorners. Dehorning with these tools is usually performed when the calves are a few weeks or months old, and these methods cause temporary setbacks in growth due to the trauma associated with them. This trauma can be avoided by dehorning the newborn calf with caustic paste. Caustic pastes cause a chemical burn when applied to the skin, and when applied at a very young age to the cells that will develop into horn tissue, the paste will prevent development of horns. Those who properly use caustic pastes boast of its ease of application and the beautiful polls that develop on their animals. Those who have improperly used caustic pastes can tell tales of disfigured calves and sloppy dehorning jobs. There is a right way and a wrong way to use these products. Following are some suggestions for success when dehorning with caustic pastes.

Feeding of Milk or Milk Replacer

Regularity in the feeding of the baby calf is important. Several factors need to be controlled for optimum calf performance during the milk-feeding phase. These factors include:

Milk is the food for mammalian babies, and nothing has ever been invented or synthesized that is superior. Some products can take its place if they closely mimic the chemical and physical properties of milk. For dairy calves, we basically have two sources of liquid "milk" - whole milk from a cow or powdered milk replacer that we reconstitute to the consistency of milk. There are health, performance, and economic considerations to be made when choosing which of these will be fed.

Many dairies feed "dump" or "waste" milk to calves. This often is milk from cows that are too fresh to put into the milk tank, or from cows that have been treated for mastitis. "Fresh cow" milk is excellent for young calves. Fresh cow milk may still contain a small amount of colostral immunoglobulins for a couple of days, and even though the calf can't absorb them after the first day of life, these antibodies may provide some health benefits by combating pathogenic organisms in the lumen of the intestine. Milk from cows with mastitis may contain infectious bacteria, as well as antibiotics from the treatment of that infection. Both of these may have detrimental effects on the calf. It has been suggested that calves fed mastitic milk may harbor the mastitis bacteria on their mouth and in their saliva, possibly spreading these mastitis pathogens to the udders of other calves by sucking them. Some of these bacteria can live for a couple of years in the udder of a heifer, causing her to freshen with a case of infectious mastitis. Housing calves individually can prevent this problem. Feeding of milk that contains antibiotics is considered as one possible means by which certain bacteria may develop resistance to antibiotics. Once bacteria develop resistance to the antibiotic, that drug may no longer be effective in treating clinical infections caused by the same bacteria, and we may have a harder time combatting diseases in that calf. Indiscriminate feeding of antibiotics may also inhibit establishment of beneficial bacteria in the digestive tract of the calf.

The alternative to feeding real milk is powdered milk replacer. There are many on the market, and some are better than others. Some characteristics of a high quality milk replacer are:

There is considerable variation among milk replacers regarding sources of nutrients and nutrient content. Protein source is perhaps the greatest variable, and some protein sources are superior to others (4, 5, 10). However, no sources of protein have been found to be superior to milk proteins. A summary of protein sources used in milk replacer, and their relative suitability for young calves is presented in table 2. Most of the milk protein in today's milk replacers is whey protein, a by- product of the cheese industry. When whey proteins first started being economically available for use in milk replacers, there were concerns over its digestibility, due to the fact that it doesn't coagulate or clot in the calf's abomasum like casein proteins do. However, we now know that the digestibility of whey protein is similar to that of casein, and that there is little difference in the performance of calves fed either of them. A newer protein source is animal plasma. Performance of calves fed milk replacer in which animal plasma replaced a portion of the milk protein was reported to be similar to performance of calves fed an all-milk protein liquid feed (12, 14).

Table 2. Acceptability of different protein sources for use in milk replacer for young calves1

High Acceptability

Medium Acceptability

Low Acceptability


Dried skim milk-

Dried whey

Whey protein conc.

Dried buttermilk


Demineralized whey

Plasma proteins

Delactosed whey

Soy protein isolate

Soy protein conc.

Soy flour

Fish meal

Single cell protein

Dried meat solubles

Distillers solubles

Wheat protein

Potato protein

1 Taken from Morrill (11), with the exception that plasma proteins were moved from "Unknown Acceptability" to "High Acceptatiliby" based on recent research (12, 14).

It only takes a minute to evaluate the tag on a bag of milk replacer. When one considers that poorer quality milk replacers often lead to poorer calf performance, or even death of the calf, a few extra dollars spent for high quality ingredients may actually be the cheapest way to feed calves. Regardless of whether you feed suitable waste milk or a high quality milk replacer, you should avoid switching calves from one to the other. Again, consistency is the key to raising baby calves, and oftentimes, changing the type of milk can cause digestive upsets.

One question that is frequently asked is whether or not to feed good, salable milk to calves when waste milk is not available. A couple of considerations must be made. If you routinely feed waste milk, and will only have to feed salable milk temporarily, you may be better off doing so to avoid switching your calves from milk to milk replacer. However, if you don't normally have enough waste milk, evaluate the economics of feeding salable milk versus milk replacer. Consider the following scenario:

You can see that at these prices, it costs twice as much to feed saleable milk. Evaluate the difference in your own milk market to decide which is best for you.

The amount of milk to feed calves is sometimes debated. Calves can obtain sufficient nutrients for optimum growth during the first 2 to 3 weeks of life from 4 liters of milk or milk replacer per day (typically divided into two feedings per day). Some dairymen will intentionally feed less than this in the belief that they are preventing scours. While overfeeding of milk will cause the feces to be loose, and could cause a temporary case of non-infectious scours, two feedings per day of 2 liters of milk per feeding is not overfeeding of milk.

Scours and Treatment of Scours

Scours is one of the major health concerns of young calves. Scours is characterized by loose, watery feces, and can kill a calf fairly rapidly, depending on its severity. Scours kills the calf by a combination of dehydration, loss of electrolytes, and metabolic acidosis. Causes of scours can be classified as non-infectious and infectious. Non-infectious scours are usually caused by overfeeding of milk or a lack of consistency in our feeding program. While usually not severe enough to cause death, non-infectious scours can weaken the calf and make it more susceptible to infectious scours. Scours caused by infectious organisms are our biggest problem. The three basic categories of organisms that cause infectious scours are bacteria, viruses, and protozoa. As with most diseases, it is usually cheaper and easier to manage the problem by prevention rather than by treatment. Some measures for preventing infectious scours are:

When preventive measures fail and infectious scours occurs, finding the appropriate treatment is the key to success. The appropriate treatment depends on the causative organism. Of the bacterial scours, E. coli and Salmonella spp. are the two organisms most frequently involved in severe cases, with several other bacteria possibly involved. While bacterial scours can be treated with antibiotics, different antibiotics are effective against different organisms. This necessitates a diagnosis of the causative organism in order to select the most appropriate antibiotic therapy. Populations of scours-causing bacteria can change over time, and if the scours treatment that was successful for you in the past seems to have become ineffective, it is possible that you are now dealing with a different organism. The small amount of time, effort, and money required to collect a fecal sample from a sick calf and send it to a veterinary diagnostic laboratory is well spent when one considers that treating calves with the wrong medication is sometimes completely useless and will not prevent death of the calf.

Scours caused by viral infections usually doesn't respond to antibiotic treatment because viruses are not affected by antibiotics. The best protection against viral scours is sanitation and good colostrum management, and the most suitable therapy for viral scours is to keep the calf alive with oral electrolyte therapy until the viral infection is over. Oral electrolyte therapy will be discussed shortly.

There are two categories of protozoa that commonly cause scours; coccidia and cryptosporidia. There are products available for treating coccidiosis, but no products are currently effective against cryptosporidia. Feeding of ionophores (monensin, lasalocid, marketed as "Rumensin" and "Bovatec" respectively) has proven effective in preventing coccidial infection. Feeding or drenching with decoquinate (marketed as "Deccox") or amprolium (marketed as "Corrid") is effective in controlling coccidial infections once they get started. Again, a correct diagnosis of the cause of the disorder is essential for selection of the appropriate treatment compound. Diagnosing cryptosporidia as a source of scours is often difficult. Since no currently available compounds are effective against this organism, it can be devastating to the calf crop unless its spread is controlled by other management strategies. There are additional concerns with cryptosporidia because it can infect humans, and severe dehydration and death have been attributed to its infection of persons working around dairy animals.

Oral electrolyte therapy is a means of keeping calves alive until they can overcome the infectious organisms that are causing the scours. There are dozens of commercial oral electrolyte products available, with a wide range of costs. There is tremendous variation in both the types and amounts of ingredients used in these products. These products are mostly designed to replace the water and electrolytes (sodium and potassium) lost during scours, and to correct the metabolic acidosis that results from loss of these electrolytes. Two types of products are used to correct the metabolic acidosis, bicarbonate compounds and metabolizable bases. Bicarbonate compounds (sodium and potassium bicarbonate) are frequently used to directly neutralize acids in the body. They also neutralize the acid in the calf's abomasum (the abomasum is supposed to be acidic all the time), which can negatively impact the calf's ability to digest protein. The protein digesting enzyme, pepsin, requires an acid condition in the abomasum to function properly, thus, oral electrolyte solutions containing the bicarbonate compounds should not be used in calves that are still being fed milk. Metabolizable bases are use to combat acidosis without affecting the pH of the stomach contents (9). Products containing metabolizable bases and no bicarbonates will not interfere with protein digestion.

Opinions among dairymen vary regarding how to use oral electrolytes, but research has clearly defined the most appropriate application. Corbett (2, 3) provided excellent discussions of the causes and treatment of scours. Perhaps the most common misconception about scours is that milk causes scours. This is not the case. While it is true that withholding milk from a scouring calf will result in less fecal material on the ground, that is by no means an indication that the calf is recovering. Many dairymen mistakenly believe that feeding of milk should be suspended while electrolyte solutions are fed to scouring calves. Garthwaite et al. (6) demonstrated that this practice does not improve the recovery rate. Additionally, continuing to feed milk along with fluids and electrolytes helps calves maintain acceptable rates of gain (6, 7).

In general, oral electrolyte solutions keep a calf alive by replacing the fluids and electrolytes (primarily sodium and potassium) it has lost, and by correcting the metabolic acidosis that develops during scours. Some guidelines for treating infectious scours and using oral electrolyte solutions are:


Sanitation is vitally important in the fight against infectious disease in young calves. Sanitation doesn't necessarily imply that everything around the calf needs to be spotlessly clean, but that everything with which the calf comes into contact is free of infectious organisms.

A few simple suggestions for practicing good sanitation around calves are:

Sanitation is one area of management where a small dose of common sense goes a long way. Try to think about whether or not you would mind sticking any of your calf equipment in your own mouth. If you would hesitate to do so because of its cleanliness, it is not clean enough for the calf.

Dry Starter Nutrition and Weaning

One of our primary objectives in raising the calf during the milk-feeding phase should be to develop its ability and desire to consume dry starter feed, and to end the necessity of feeding milk as soon as possible. Unless suitable waste milk is available, the milk-feeding phase will cost more per day than any time up until the calf reaches close to 400 kg body weight (depending on forage and grain prices). Most of this expense is the milk or milk replacer, but a considerable amount of labor must also be considered. There are several management practices that can be employed to help enhance dry feed intake by the calf.

Naturally, calves won't eat much dry feed in the first few days, but calves who are continuously exposed to dry feed from an early age will begin to consume significant amounts of it earlier than calves who do not have early exposure. Consumption of dry feed is important because it should be our primary criterion for determining if a calf is ready to be weaned. When calves are taking in significantly more sustenance (protein, energy, minerals) from dry feed than they would from 4 liters of milk or milk replacer, they no longer need the milk to grow at an acceptable rate. It will take about 0.68 kg of an 18% protein all grain starter to provide this nourishment. Calves that consume at least 0.68 kg for three or more consecutive days are indicating sufficient intake for weaning (11). If the above-mentioned management is followed, and if the calves have suffered no setbacks due to scours or other illness, calves can be successfully weaned from milk at 5 weeks of age without jeopardizing their subsequent growth rates (19). A feeding strategy that seems to encourage starter intake while minimizing the stress of abrupt cessation of milk feeding is to cut the calves back to one feeding of two liters of milk per day during the last week before weaning. Although the calves will want the extra milk, they will quickly learn that eating more starter feed will ease their hunger. Intake of starter feed will increase rapidly, and from this point onward, calves should be off to a good start as herd replacements.

Dry starter feeds need to be palatable as well as provide the nutrients that the calf needs for maintenance and growth. Recommended nutrient content of a dry calf starter is given in Table 3.

It was once believed that calves needed to eat hay (for its "scratch factor") in order to develop early rumen function. We now know that it is actually volatile fatty acids (VFA) from the fermentation of feeds that enhances development of rumen function, and the VFA produced from the fermentation of grains is more stimulatory to ruminal development . There is little fear of ruminal acidosis in calves on all grain diets up until weaning time. Occasionally a calf may bloat, but an oral drench of poloxaline ("Bloat Guard", "TheraBloat") will usually relieve the problem. Some calves are chronic bloaters, and should be watched carefully until they grow out of the problem.

There currently are several "direct fed microbial" or "probiotic" products that are marketed to promote better performance (feed intake, growth rate, etc.) in calves. While controlled research on many of these products is scarce, they may have some benefit. These products come in different forms (pastes, powders), and vary somewhat with regard to their composition. Most, however, will contain species of live bacteria from the Lactobacillus genus that are considered to be beneficial to the health and function of the gastrointestinal tract (8). Vazquez (17) evaluated the efficacy of one of these products, and reported that calves who were given an oral dose of seven grams of probiotic paste at five days of age and who also received two grams of powdered probiotic product daily in their milk consumed more starter feed and increased in heart girth measurement more than calves who did not receive this treatment. Of the calves treated with the probiotic, 53% met weaning criteria (0.68 kg starter intake for 3 consecutive days) at 29 days of age, compared to 22% of the untreated calves. Patterns of dry starter intake for these two groups of calves are depicted in Figure 1. The use of probiotic products for young calves needs further study to determine the most effective organisms and applications to use.

Table 3. Recommended Nutrient Content of Dry Calf Starter1,2



Net Energy for Maintenance (Mcal/kg)


Net Energy for Gain (Mcal/kg)


Metabolizable Energy (Mcal/kg)


Digestible Energy (Mcal/kg)


Total Digestible Nutrients (% of dry matter)


Crude Protein (% of dry matter)


Fat or Ether Extract (% of dry matter)









50.0 ppm





0.1 ppm





10.0 ppm





40.0 ppm





40.0 ppm





0.25 ppm





0.3 ppm



66 IU/kg dry matter

1Taken from NRC (13), except for Vitamin E recommendation.

2 All requirements expressed as concentration in diet dry matter.

3 Reddy et al. (15)


Success in raising the calf from birth to weaning does not happen by accident. By adequate preparation, observation, good husbandry, colostrum management, sanitation, disease prevention and control, and good nutrition, are the key to maximizing calf growth and keeping death losses below 5%.


  1. Beef Today, 230 W. Washington Square, Philadelphia, PA. 19106-3599 and Elanco Animal Health, Lilly Corporate Center, Indianapolis, IN. 46285. Video "How to Save More Calves at Calving." 1994.
  2. Corbett, R. B. 1995. The Vets Voice, therapy of neonatal calf diarrhea. Page 8 in Agribusiness Dairyman, April, 1995
  3. Corbett, R. B. 1995. The Vets Voice, therapy of neonatal calf diarrhea - part II. Page 6 in Agribusiness Dairyman, May, 1995
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  8. Higginbotham, G. E. and D. L. Bath. 1993. Evaluation of Lactobacillus fermentation cultures in calf feeding systems. J. Dairy Sci. 76:615.
  9. Kasari, T. R. 1990. Metabolic acidosis in diarrheic calves: the importance of alkalinizing agents in therepy. Vet. Clin. North Am. Food Anim. Pract. 6:29.
  10. Mir, P. S., J. H. Burton, and J. G. Buchanon-Smith. 1991. Nutritional performance of calves fed milk replacers containing processed soybean products. Can. J. Anim. Sci. 71:97
  11. Morrill, J.L. -. The Calf: Birth to 12 Weeks. Page 401 in Large Dairy Herd Management. Van Horn and Wilcox, eds., American Dairy Science Association, Champaign, IL.
  12. Morrill, J. L., J. M. Morrill, and A.M. Feyerherm. 1995. Plasma proteins and a probiotic as ingredients in milk replacer. J. Dairy Sci. 78:902
  13. National Research Council. 1989. Nutrient Requirements of Dairy Cattle. 6th rev. ed. Natl. Acad. Sci. Washington, DC.
  14. Quigley, J. D., and J. K Bernard. 1996. Milk replacers with and without animal plasma for dairy calves. J. Dairy Sci. 79:1881.
  15. Reddy, P. G., J. L. Morrill, and R. A. Frey. 1987. Vitamin E requirements of dairy calves. J. Dairy Sci. 70:123.
  16. Stott, G. H. and A. Fellah. 1983. Colostral immunoglobulin absorption linearly related to concentration for calves. J. Dairy Sci. 66:1319.
  17. Vazquez, F., T. F. Brown and R. D. Wittie. 1997. Performance of newborn calves fed a commercial probiotic. J. Dairy Sci. 80 (Suppl. 1):189.
  18. Weeth, H. J. and C. F. Speth. 1968. Estimation of bovine plasma protein from refractive index. J. Anim. Sci. 27:146.
  19. Winter, K. A. 1985. Comparative performance and digestibility in dairy calves weaned at three, five, and seven weeks of age. Can. J. Anim. Sci. 65:445.