Pasteurized Waste Milk: A Viable Alternative to Traditional Calf Feeds

By Madison May

Eastern Mennonite High School

Research Writing

December 2011

Thesis: On-farm pasteurization of waste milk provides a safe source of calf nutrition and

an economically viable alternative to traditional liquid feeds.

I. Pasteurization of waste milk eliminates harmful pathogens that may be present in fresh

waste milk, resulting in a safe liquid feed.

A. Raw waste milk can contain large quantities of potentially harmful pathogens.

B. Pasteurization successfully eliminates the vast majority of these pathogens.

C. Calves fed pasteurized milk experience lower mortality rates and suffer less

frequently from illness and infection.

II. Pasteurization of waste milk provides a more economical alternative than milk replacer or

salable milk.

A. Waste milk is essentially a free resource for farmers.

B. Calves fed pasteurized waste milk experience fewer sick days and require

fewer veterinary interventions, reducing expenditures.

C. Feeding waste milk results in a greater daily weight gain than feeding equal

quantities of milk replacer, which in turn results in increased profit.

D. Feeding waste milk allows farmers to dispose of non-salable milk and recoup

losses.

III. Extensive research has addressed common pasteurized waste milk concerns.

A. High-temperature short-time pasteurization techniques have made the

pasteurization process more time efficient and less labor intensive.

B. Proper milk management prevents pathogen exposure.

C. Waste milk variability and availability seldom pose problems.

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In 2007, a small investment for the Dueppengiesser family soon developed into a $30,000

increase in annual income. The Dueppengiesser family, owners of a New York dairy farm,

became one of seven dairies to participate in the New York Farm Viability Institute’s pilot waste

milk pasteurization project. The family purchased a batch pasteurizer for $10,000 and the

investment paid for itself in only four months. At the Dueppengiesser’s dairy, Ransom Rail, 90

gallons of waste milk are pasteurized twice daily to feed the 85-90 calves usually present. The

batch pasteurizer heats the milk to approximately 145 degrees for thirty minutes and successfully

eliminates the overwhelming majority of the bacteria contained in the raw waste milk. The

process allows the family to make use of waste milk that traditionally would have been discarded

due to high microbial content. The family no longer forfeits $100 each day to pay for costly milk

replacer, requiring an average of only $17 to pay for pasteurizer operation. Along with the

decrease in overhead, the thousand-cow dairy has also benefited from a noted increase in daily

calf weight gain and fewer medical concerns among their replacement herd. Owner Peter

Dueppengiesser praises the new addition to the dairy, asserting that the batch pasteurizer

represented a “modest investment and a quick payoff” (Thomas). No doubt the other participants

in the New York Farm Viability Institute’s pilot project would share the Dueppengiesser’s

sentiments.

Pasteurization has the potential to transform a potentially hazardous waste product into a

safe, nutritious, and economically sound source of sustenance. “Professional heifer growers are

faced with the challenge of raising healthy calves while still paying close attention to rearing

costs and profit,” suggests Sandra Godden, a prominent milk researcher at the University of

Minnesota. A delicate balance must be found between calf health and feed cost. In the current

state of the U. S. economy, however, farmers and dairymen cannot often afford to sacrifice either

of the two. Milk replacer does not provide adequate weight gain to justify its prohibitively high

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price and often lacks the nutrition young calves require. Likewise, feeding salable milk results in

a severe reduction in potential profit; the improved calf weight gain cannot justify the increased

expenditure. Although considered a “free” liquid feed, raw waste milk has raised serious health

concerns from veterinary professionals, and the increased calf mortality rates counteract the

reduced feed cost. The alternative, pasteurized waste milk, may soon serve as the choice liquid

feed of the nation’s farmers. On-farm pasteurization of waste milk provides a safe source of calf

nutrition and an economically viable alternative to traditional liquid feeds.

Though once widely considered a practical liquid feed for calves, raw waste milk has

acquired an undesirable reputation in recent decades. The popularity of feeding excess colostrum

and transition milk to calves peaked in the early 1980s and has since declined because of health

and sanitation concerns (Drackley). Defined as milk rendered unsalable because of residual

antibiotics, waste milk includes colostrum, transition milk, mastitic milk, and treated milk

(Kesler). Nearly 87% of all 2002 U.S. dairy farms reported utilizing waste milk as part of a

liquid feeding regimen, while only 52% of all modern dairy farms now feed replacement calves

raw colostrum or transition milk and a mere 34% of current farms feed raw mastitic milk or

treated milk (Stabel; Drackley). Instead, an increasing number of producers utilize pasteurization

to destroy waste milk bacteria and provide a safe, nutrient-rich calf feed.

Raw waste milk has often drawn concerns from farmers and researchers because of its

high pathogen levels. Although a 1981 study by Pennsylvania State University addressed these

concerns and reported that feeding raw waste milk to calves poses no risk, similar studies have

returned different results. Sandra Godden reported significantly greater bacterial concentrations

in waste milk than traditional whole milk, and a 2004 study by J.R. Stabel claimed increased

mortality rates in waste milk fed calves. The potentially detrimental nature of waste milk gives

researchers and farmers alike a cause for concern.

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Pasteurized waste milk presents a safe substitute to conventional raw waste milk.

Decades of research have confirmed the health benefits of waste milk pasteurization.

Pasteurization of waste milk at approximately 75º C for as little as 15 to 20 seconds proved

sufficient to eliminate Mycoplasma bacteria from waste milk (Stabel). A 2004 study conducted

by Iowa State University confirmed waste milk pasteurization also eliminated Salmonella and M.

paratuberculosis, common pathogens known to cause illness such as Johne’s disease. Other

bacteria eliminated by pasteurization include Mycobacterium avium, Listeria monocytogenes,

Campylobacter spp., Mycobacterium bovis, Mycobacterium californicum, Mycobacterium

canadese, Stapyhlcoccus aureus, and Escherichia coli (Godden Review). Batch pasteurization

and High-Temperature Short-Time pasteurization techniques effectively reduced bacterial

concentrations in waste milk.

The bacterial reduction associated with pasteurization returns incredible health benefits.

According to research from 2005, calves fed pasteurized waste milk experienced less frequent

illness and reduced mortality rates than calves fed raw waste milk (Godden “Economic”). A

study by Oklahoma State University echoed these results, concluding that feeding pasteurized

waste milk reduced incidences of diarrhea and pneumonia (Waldner). Jamaluddin reached a

similar conclusion after conducting a study comparing pasteurized waste milk and raw waste

milk in 1996. Calves fed pasteurized waste milk required fewer veterinary visits and exhibited

decreased mortality rates (Stabel). The decrease in potentially harmful bacteria enabled the

production of a more beneficial liquid calf feed.

When compared to milk replacer, the health advantages of feeding pasteurized waste

milk become clear. While 11.5% of calves fed milk replacer died prior to weaning, a mere 2.3%

of calves fed pasteurized nonsalable milk died (Godden “Economic”). This study, a comparison

of milk replacer and pasteurized milk in a clinical trial of 438 dairy calves, revealed lower illness

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and mortality rates in calves fed pasteurized milk when compared to calves fed milk replacer

(Godden “Economic”). Pasteurized waste milk presents a healthier alternative to artificial milk

replacer.

Economic value accompanies the numerous health benefits of pasteurized waste milk. On

a dairy, every ounce of waste milk reduces potential economic gain and necessitates disposal

(Kesler). T. H. Blosser estimates that a typical dairy cow produces 48 to 136 pounds (22 to 62

kg) of waste milk each year. This figure represents a significant reduction of revenue for the

average dairy (Godden Review). Blosser attempted to measure this amount in 1976 and

concluded that mastitic milk accounted for $117.35 in annual losses per dairy cow. When

adjusted for current inflation, this figure approaches $450. Nationwide, Blosser reports, losses

due to mastitic milk amounted to approximately $1.3 billion per year, an amount equivalent to

nearly $5 billion today. Blosser’s study, however, did not include the substantial profit forfeited

because of over-quota milk and transition milk. The use of pasteurized waste milk allows a dairy

farmer to recoup a portion of these losses and decrease the cost of raising replacement cattle.

Raising replacement cattle certainly accounts for a significant portion of the expenses on

a modern dairy farm. James Drackley estimated that one fifth of all dairy overhead stems for

raising future dairy calves. A large portion of this expenditure can be attributed to the cost of

liquid feed. Unlike milk replacer, feeding pasteurized waste milk requires no continual

investment. A dairy farmer need make only a single purchase. Utilizing the free resource that

waste milk presents could allow modern day farmers to reduce the cost of operation and increase

profit yield.

The aforementioned health benefits associated with pasteurized waste milk also result in

reduced medical expenses. As Jamaluddin revealed in 1996, feeding pasteurized waste milk

indirectly lowers veterinary costs. Calves fed pasteurized waste milk were significantly less

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likely to require medical attention than calves fed traditional waste milk (Stabel). The enhanced

protein and fat levels of waste milk, coupled with the bacterial reduction provided by

pasteurization, likely account for the decreased necessity of veterinary intervention. In fact,

several studies have compared the health of calves fed pasteurized waste milk and calves fed

salable whole milk only to find little difference between the two (Drackley; Kesler). The health

benefits of pasteurized waste milk lead to fewer veterinary visits, which in turn lead to improved

profit margins, a definite boon to any farmer struggling in the current economy.

Pasteurized waste milk also contains the potential for rapid calf growth. Due to high

concentrations of protein and fat in colostrum and transition milk, waste milk provides levels of

metabolizable energy comparable to that of salable whole milk (YuYu). Godden reported solid

content ranging from 16% to 18% in pasteurized waste milk, figures that match average

concentrations in whole milk. Jorgensen, a researcher at the University of Wisconsin, reported

that pasteurized waste milk actually contains a slightly greater concentration of metabolizable

energy than whole milk, with 5.45 mcals/kg instead of 5.37 mcals/kg. Although the highly

variable nature of waste milk means that levels may fluctuate, Jorgensen’s research highlights

the possibilities that pasteurized waste milk holds.

Although generally considered affordable, milk replacer cannot compete with the

nutritional content of actual milk. Farmers who choose to feed milk replacer must consider the

20 to 25% reduction of metabolizable energy that the decision entails (Drackley). This reduction

in metabolizable energy results in decreased calf weight gain (Godden “Economic”). To achieve

weight gains similar to those of milk, farmers must feed increased quantities of milk replacer.

University studies indicate that calf weight gain remains consistent with the high

nutritional content of pasteurized waste milk. In 1996, Jamaluddin concluded that pasteurized

waste milk resulted in greater daily weight gain than conventional waste milk. The University of

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Minnesota likewise reported increases in weight gain of several hundred grams when comparing

pasteurized waste milk to milk replacer (Godden Review). In a clinical trial with over 400 calves,

the treatment group assigned pasteurized waste milk gained an average of 58.8 lbs before

weaning while the treatment group assigned milk replacer gained an average of only 44.3 lbs.

(Godden Review). This amounts to an average daily gain of 1.04 lbs/day for calves fed

pasteurized waste milk versus the 0.76 lbs/day gained by the milk replacer treatment group

(Godden Review). Most studies examined maintained that weight gain in calves fed pasteurized

waste milk closely matched weight gain in calves fed whole milk, the ideal liquid feed for a

growing calf (Godden Review; Drackley). Farmers need not expect reduction in calf weight gain

when feeding pasteurized waste milk.

An increase in revenue accompanies the additional weight gained by calves. By

Jamaluddin’s estimates, calves fed pasteurized waste milk grossed approximately $8.41 more

than calves fed raw waste milk. James Drackley drew similar conclusions, suggesting that the

cost of each additional kg of calf weight amounted to less than two dollars when feeding

pasteurized waste milk. Milk replacer, in contrast, required an investment of about four dollars

(Drackley). In the case of the Dueppengiesser family, feeding pasteurized waste milk instead of

milk replacer allowed the dairy to cut expenses by eighty percent and earn an additional $30,000

per year. Although studies have indicated varying degrees of improvement, all have seemed to

return positive results.

Opponents of waste milk pasteurization attack the pasteurization process, stating that

pasteurization may prove insufficient to eliminate large quantities of bacteria. Even Sandra

Godden, waste milk pasteurization proponent and researcher at the University of Minnesota,

concedes that the pasteurization process does not sterilize waste milk. Prohibitively high initial

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bacterial concentrations may cause pasteurization to result in inadequate bacterial reduction

(Godden Review). Pasteurization alone does not suffice to eliminate all bacteria.

The solution to this problem proves quite simple. Farmers should take care to chill and

store waste milk in sanitary containers prior to pasteurization in order to reduce the amount of

viable bacteria that survive the pasteurization process (Godden Review). Bacterial replication

slows in cool environments, so waste milk refrigeration prevents excessive bacterial growth. By

limiting initial bacterial counts, refrigeration decreases the likelihood of bacterial survival.

However, Godden suggest that farmers also strictly regulate post-pasteurization milk storage.

Milk should likewise be refrigerated and stored in a sanitary container (Godden Review). Failure

to do so could allow exponential bacterial growth to re-contaminate the pasteurized milk. E. M.

Kesler, a former researcher at Pennsylvania State University, echoes Godden’s cautionary tone

and suggests that waste milk storage should not exceed three days. Feeding milk soon after

pasteurization allows no chance for bacterial growth and limits the danger of pathogen exposure.

Critics might also argue that requiring refrigeration makes feeding waste milk

impractical. Elizondo, a second researcher from Pennsylvania State University, suggests that

farmers wishing to utilize pasteurized waste milk maintain adequate refrigeration facilities.

However, since most large dairies already have refrigeration facilities in place that could easily

accompany additional milk, waste milk pasteurization remains practical (YuYu). Small dairies

that might lack these facilities need not worry either. Smaller-scale dairies do not require

facilities for refrigeration if calves receive waste milk soon after pasteurization (YuYu). Since

smaller farms likely raise fewer replacement calves, this process should not cause complications.

Other skeptics may suggest that the length of time necessary for waste milk

pasteurization makes waste milk pasteurization prohibitively time consuming and labor

intensive. Although this may prove true of batch pasteurization, advances in pasteurization

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technology have countered this argument. Commercial pasteurizers now utilize high-temperature

short-time (HTST) pasteurization methods (Stabel). HTST pasteurizers force waste milk through

conductive tubes surrounded by hot water and quickly raise the milk temperature to 74 to 76

degrees Celsius (Stabel). At these temperatures, pasteurization occurs in as little as fifteen to

twenty seconds, making the HTST pasteurization process remarkably more efficient that

conventional batch pasteurization methods (Stabel). This method seems to have quickly become

the industry standard. Waste milk pasteurization now requires little labor and minimal effort.

Farmers concerned about waste milk availability, the development of antibiotic-resistant

bacteria in calves’ gut linings, or variability in the composition of waste milk might also be

comforted by decades of scientific research. Because frequent switches between waste milk,

whole milk, and milk replacer had no significant detrimental effect on calves, James Drackley of

the University of Illinois argues that milk replacer or whole milk can supplement pasteurized

waste milk (Drackley). Similarly, a 1990 study on antibiotic resistant bacteria reported that

feeding treated milk did not significantly increase the number of antibiotic-resistant gut bacteria

(Godden Review). Finally, a 1978 study by Foley and Otterby concluded that the daily variation

in the composition of waste milk did not result in decreased weight gain or increased diarrhea

incidence. Clinical research has also quelled these common waste milk concerns.

Numerous studies have indicated that pasteurized waste milk provides a nutritional and

economical liquid feed. Research has documented the potential of waste milk pasteurization to

decrease farm expenditures, increase profit, and provide ample nutrition for growing calves;

conventional liquid feeds such as milk replacer and raw waste milk cannot compete with the

economic benefits of this modern alternative. Pasteurization has been proven to transform a

waste product into a potential source of income, generating weight gain similar to whole milk at

a small fraction of the cost. Pasteurized waste milk represents a tremendous opportunity for

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cattle farmers across the country, and dairymen such as Peter Dueppengiesser can attest to its

benefits. This unconventional liquid feed will likely provide farmers with the additional revenue

required to maintain a dairy in today’s troubled economy.

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Works Cited

Blosser, T.H. "Economic Losses from and the National Research Program on Mastitis in the

United States." Journal of Dairy Science 62.1 (1979): 119-27. Web. 17 Nov. 2011

Drackley, James K. Critical Evaluation of Feeding Options for Replacement Calves. University

of Illinois. Web. 9 Nov. 2011.

Elizondo-Salazar, Jorge A. "Pasteurization of Waste Milk for Dairy Calves." dasweb.psu.edu.

Pennsylvania State University. Web. 16 Nov. 2011.

Foley, John A., and D.E. Otterby. "Performance of Calves Fed Colostrum Stored by Freezing,

Fermentation, or Treatment with Lactic or Adipic Acid [1] and [2]." Journal of Dairy

Science 62.3 (1979): 459-67. Print.

Godden, Sandra M., John P. Fetrow, Joellen M. Feirtag, Lorissa R. Green, and Scott J. Wells.

"Economic Analysis of Feeding Pasteurized Nonsalable Milk versus Conventional Milk

Replacer to Dairy Calves." Journal of the American Veterinary Medical Association

226.9 (2005): 1547-554. Web. 14 Nov. 2011.

Godden, J. Feirtag, L. Green, S. Wells, and J. Fetrow, eds. A Review of Issues Surrounding

the Feeding of Waste Milk and the Pasteurization of Waste Milk and Colostrum. May,

2003. University of Minnesota. Minnesota Dairy Health Conference College of

Veterinary Medicine, n.d. Web.

Jamaluddin, A. A., T. E. Carpenter, D. W. Hird, and M. C. Thurmond. 1996. Economics of

feeding pasteurized colostrum and pasteurized waste milk to dairy calves. Journal of the

American Veterinary Medical Association 209:751.

Jorgensen, Matt, Pat Hoffman, and Andy Nytes. Efficacy of On-Farm Pasteurized Waste Milk

Systems on Upper Midwest Dairy and Custom Calf Rearing Operations. University of

Wisconsin. Web. 14 Nov. 2011.

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Kessler, E. M. Feeding Mastitic Milk to Calves. journals.elsevierhealth.com. The Pennsylvania

Stabel, J.R., S. Hurd, L. Calvente, and R.F. Rosenbusch. "Destruction of Mycobacterium

Paratuberculosis, Salmonella Spp., and Mycoplasma Spp. in Raw Milk by a

Commercial On-Farm High-Temperature, Short-Time Pasteurizer." Journal of Dairy

Science 87.7 (2004). Web. 9 Nov. 2011

Thomas, Ken. "New York Dairy Producers Pay Attention to Details." Country Folks. 25 June

2007. Country Folks. Country Folks. Web. 8 Dec. 2011.

Waldner, Dan N., Michael L. Looper, Ellen R. Jordan, and Sandra A. Stokes. Feeding Waste

Milk to Dairy Calves. Oklahoma State University. Web. 16 Nov. 2011.

Yu, Yu, J.B. Stone, and M.R. Wilson. "Fermented Bovine Colostrum for Holstein Replacement

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