Monitor your pasteurized milk feeding system

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Source: University of Minnesota Extension, Sandra Godden, DVM, College of Veterinary Medicine

Quick Facts

With proper management and monitoring, you can consistently deliver a clean, high quality milk diet to your calves, and maximize the benefits captured from your pasteurized milk feeding program.

For best results:

  • Create a standard operation procedure (SOP).
  • Train farm staff in implementing these SOPs.
  • Implement a routine monitoring program.

Benefits of feeding calves whole milk

  • Feeding calves non-saleable (hospital) milk or saleable tank milk can allow producers to capture important growth, health and economic benefits, as compared to conventional milk replacer feeding programs.
  • Improvements in average daily gain in the preweaning period have been associated with significant improvements in first and second lactation milk production.
  • Other benefits of providing a high plane of nutrition from whole milk can include improved immune function and health.

Beware of disease-causing bacteria

Despite the tremendous benefits that whole milk diets can offer, feeding raw milk may expose calves to infectious agents, such as the one that causes Johne’s disease (Mycobacterium avium ssp. paratuberculosis), as well as Salmonella, Mycoplasma and E. coli.

However, these risks can be largely addressed by adopting commercial on-farm pasteurization systems.

While many farms achieve excellent results feeding pasteurized milk, producers must remember that, if not properly managed and monitored, these systems can suffer from problems like variation in milk nutrient composition or inadequate pasteurization.

Managing the pasteurized milk feeding system

Harvest, move and store high quality raw milk before pasteurization

  • Do not feed watery or bloody milk from cows with clinical mastitis, as nutrient composition will be poor.

  • Prevent dilution of milk with water (do not discharge parlor wash water into the hospital milk storage tank).

  • Pasteurize within two hours of harvest, or chill raw milk (40 degrees F) until ready to pasteurize.

  • If chilling and storing raw milk, pasteurize and feed it within three days of harvest.

  • Agitate milk well before transferring to pasteurizer.

  • Clean or sanitize all harvest, transfer or storage equipment.

Pasteurize the milk

  • Use Pasteurized Milk Ordinance (PMO) times and temperatures:

    • High Temperature – Short Time (or flash) pasteurizer: 161 degrees F for 15 seconds

    • Batch pasteurization: 145 degrees F for 30 minutes

  • Do not repasteurize milk.

  • Clean or sanitize pasteurization equipment.

Note: Ultraviolet (UV) treatment is significantly less effective in reducing bacteria in milk as compared to traditional heat-based pasteurization systems. If you already own a UV system, be extra vigilant to monitor its effectiveness.

Feed pasteurized milk to calves without recontaminating it

  • Feed milk within two hours of pasteurizing or rapidly chill until ready to feed.
    (If chilled, you must then rewarm to 100-105 degrees F before feeding to calves.)

  • If milk is not fed immediately after pasteurizing, agitate well prior to delivery.

  • Clean or sanitize all milk transfer and feeding equipment.

Monitor the pasteurization feeding system

Monitor function of the pasteurization equipment

  • Monitor times and temperatures reached with every batch (use chart recorder)

    • HTST pasteurizer: 161°F x 15 seconds

    • Batch pasteurizer: 145°F x 30 minutes

Monitor the adequacy of raw and pasteurized milk handling, as well as pasteurizer function

  • Periodic (monthly) culture of serial milk samples for total plate count (TPC):

    • Pre-pasteurized milk: more than 1 million cfu/mL

    • Post-pasteurized milk: more than 20,000 cfu/mL

    • Sample in front of calf: more than 50,000 cfu/mL

Monitor the quality of whole milk being fed

  • Use a Brix refractometer to estimate total solids (TS). Check at least weekly.

    • TS in whole milk is typically 12 to 13.5 percent. This will read as 10 to 12 percent on Brix scale (Brix reading + 2% = predicted total solids % in whole milk)

  • If you notice curd formation in pasteurized milk, investigate if milk is fermented due to excessive storage time or warm storage conditions of raw milk prior to pasteurization:

    • Measure milk pH. Goal= less than 6.5 (expected trouble if pH is more than 5.0)