Tuesday, February 18, 2014

Everyone Knows the Dry Matter 
Composition of Waste Milk. Right?
Everyone knows that the dry matter composition of waste milk is 13 percent. Right?
No. Wrong!
I was pleased to find in a recent press release from Penn State the results of monitoring waste milk dry matter composition on nine dairy farms over a period fifteen days.
Farm  Average  Minimum  Maximum
#        D.M.       D.M.          D.M.
1          10.7        10.1           11.2
2          10.5          9.4           13.9     
3          10.1          9.3        10.8
4          10.5          8.6           11.7
5          10.3          8.3           11.0
6          10.1          9.0           10.9
7          10.2          9.8           10.7
8          10.8        10.2           11.8
9          10.3          9.7           10.6
Given the average dry matter from these nine farms is about 10.4 percent, the question is,"What rate of gain would we expect from feeding this milk to calves?"
If we assume a 90 pound calf in cold housing (20F) being fed this milk that tests 3.5% protein and 4.4% fat, then with the 10.4 dry matter waste milk:
Feeding  Estimated
Level      Rate of Gain
(Daily)    (Daily)
   4              Weight Loss
   5              0.5
   6              0.9
   7              1.3
   8              1.5
This can be compared with the same conditions feeding waste milk averaging 14% dry matter:
Feeding  Estimated
Level      Rate of Gain
(Daily)    (Daily)
  4               0.2
  5               0.8
  6               1.3
  7               1.7 
  8               1.9
1. Measure, don't guess, dry matter in waste milk - it's easy to be very wrong.
2. Higher dry matter does make a difference in cold weather feeding for young calves. 


Joe Pasch said...

How would I test the DM of the waste milk on my farm

Emily Achen said...

I was wondering the same.

Nemo said...

Dear Dr. Leadley,
I am a student at Veterinary School of Lisbon University. My internship concerns studying the statistical relationship between feeding calves with waste milk and the appearance and dissemination of multi-resistant bacteria. I came across your post when searching for nutritive characteristics of waste milk (such as dry matter percentage), but I can't find the Penn State press release you mentioned. If it's not much trouble, could you help me find it? Thank you very much. I'll expect your answer through this channel, but we can exchange email addresses, if you want. Thank you very much. Best regards,
Manuel Cardoso