Friday, March 29, 2019

Calf Starter Particle Size

Dr. Noah Litherland (Vita Plus company) has a good YouTube presentation on calf starter particle size. [ ] This was included in the VitaPlus Starting Strong posting dated 3/20/2019.

Main point - calves prefer eating calf starter with low fines content.

How do we create fines on farm?
His points:
  • each time we run pellets through an auger fines content may go up 2 to 5%.
  • small diameter augers cause more fines increase than larger diameter ones.
  • the steeper the incline of the auger the greater the increase in fines.
I would add one more factor - higher speed auger operation creates more fines than slower speeds. 

One operation that I worked with experienced a fines issue in grower pellet feed - observed between 10 and 15 percent. 

 Without Dr. Litherland's guidance I collected this information:
1. Pellets were transported to the dairy in one of their 10-wheeler dump trucks. Samples collected at this point had between 2 and  4 percent fines. 

2. Pellets were dumped into the same pit that handled the farm's grains - transferred to a bin by elevator - no auger.

3. Now for the good part - they were transferred out of this bin using a small diameter auger set at a very steep angle due to space limitations, very high speed to save time filling the two-wheel grain cart used for supplying the self feeders at heifer barn.

4. This grain cart used an auger at the bottom to deliver pellets to the back of the cart where another vertical auger delivered the grain to the self feeders.

5. The staff person at the heifer barn refilled the self feeders from this two-wheel grain cart two times a week. He was observed running the PTO for the grain cart with the tractor engine at nearly full speed - to minimize time filling self feeders. 

6. A sample collected from this discharge auger was found to have between 10 and 15 percent fines. This may be compared to a sample checked as the pellets arrived at the farm less than 4 percent fines.

The dairy was very effective in creating fines.

Thursday, March 28, 2019

How much milk with calves drink when 
offered free-choice (ad libitum)

How much milk with calves drink when offered free-choice or ad libitum?

This resource at describes the changes over the first 35 days of life.

Key points:

  • When milk intake is not restricted expect calves to drink large amounts of milk. 
  •  Expect large variations among calves in milk consumption. 
  •  Expect significant changes in levels of milk intake from week-to-week. 
  •  In environments with significant parasite exposure, appetites tend to be depressed during infections. 
  •  Expressed as a percentage of live weight, milk consumption tends to go down as dairy heifer calves with free-choice milk, water and concentrate get past about three weeks of age
Link is HERE or url is 

Wednesday, March 27, 2019

Testing for Passive Transfer of Immunity

There is a resource on testing for passive immunity at that includes these topics:

1. How to test for immunity levels
2. Why is passive transfer of immunity important?
3. How can I test for the rate of passive transfer of immunity?
4. Sampling at the proper time and age for reliability.
5. Collecting the blood sample.
6. Handling the blood sample carefully.
7. Separating serum from red blood cells.
8. Using the refractometer.
9. What do the values mean?
10. What BSTP (blood serum total protein) goals should a farm have?
11. What do BSTP values mean for newborn management?

The URL is

or try this link  click HERE for testing for passive transfer

Friday, March 22, 2019

Starter grain intake among intensive milk-fed calves

As part of an experimental design testing fat levels  in calf starter grains intakes were collected on regular 18% c.p. starter. The calves were fed a 23-19 milk replacer  at the rates of :
     Week 1 = 6.3 qts/day @ 12.5% solids or 1.6# of powder
     Weeks 2-7 = 6.3 qts/day @ 15% solids or 2# of powder
     Week 8 = one-half of previous week or 1# of powder daily
All calves had free-choice water, calf starter and chopped straw.

Some of the calves were fed conventional starter grain. So, looking at just these calves what did they find?

What about calf starter intake? (average pounds per day) (volume estimates based on 1 quart equals roughly one pound)

Week one = almost none
Week two = just more than none
Week three = 0.2#/day or 0.8 cups - small handful
Week four = 0.4#/day or 1.6 cups
Week five = 0.8#/day or between 3 and 4 cups
Week six = 1.2#/day or well over 1 quart
Week seven = 1.8#/day or nearly  2 quarts
Week eight (on half milk ration this week) = 3.3# or over 3 quarts
Then, 4 weeks after weaning:
Week 12  (no hay, grain only) = just over 8#/day

What does this tell us about rumen development?
1. By 28 days calves were consuming enough grain to begin the rumen development process. We can begin counting the 21 days required for enough papillae development to support maintenance and growth.

2. By 42 days (week 6) calves are starting to eat enough starter grain to significantly supplement their milk ration. Rumen development is progressing well and lots of fermentation-based protein is supplementing the milk proteins.

3. At 49 days milk is cut to one-half per day - now, the calves need lots of energy and protein from grain. It has been 21 days since significant starter intake began - plenty of papillae surface now present to absorb the energy needed for growth.

4. By 56-60 days the calf is beginning to eat enough grain to support maintenance and between one and two pounds of growth per day. As long as she does not over-eat on hay this ration will soon support 2 to 2.5#/day growth.

5. They followed these calves out to 12 weeks of age - by then they were eating an average of 8+ pounds of starter grain per day (enough to support around 2.5#/day gain).

If I had a preference on the weaning for calves like this I would have set up the one-half milk ration to extend for 10 to 14 days rather than just 7 days. In an ideal situation maybe the 7 day period would work well - but remember Murphy's Law [If any can go wrong, it well], the longer step-down interval accommodates the wide variation among calves in rumen development rates so we get a more uniform accommodation to full weaning.

Reference: Berends, H. and Others "Effect of fat inclusion on starter feeds for dairy calves by mixing increasing levels of a high-fat extruded pellet with a conventional highly fermentable pellet." Journal of Dairy Science 101:10962-10972 (December, 2018).

Wednesday, March 20, 2019

Once-A-Day Milk Feeding for Calves:
Good Gains under Certain Conditions

A research team at Penn State University set up a milk feeding trial to compare once-a-day vs. twice-a-day milk feeding. A good colostrum management program resulting in average blood serum total protein average values of 6.0 fo calves in both feeding treatments. All calves had free-choice access to both water and calf starter grain. This was a small trial with 48 calves - 24 at 2X and 24 at 1X feeding.

On days 1-7 all the calves received two equal feedings a day for a total of 6.3 quarts (6 liters).
Starting on day 7 one-half of the calves continued on this twice-a-day feeding program.
Starting on day 7 one-half of the calves were changed to one milk feeding in the morning of 6.3 quarts.

Results? There was a small trend for 1X calves to gain a bit more than the 2X calves - that is, 3.5 pounds total gain more measured at 42 days of age. 

Authors conclusion was that under these conditions [(1) fed pasteurized whole milk  and (2) maximum volume of milk 6.3 quarts a day] both feeding programs were equally effective.

My conclusions are:
1. under this condition - a milk source where the protein source is primarily casein (NOT milk replacer where the protein is primarily whey protein) and milk is limited to 6.3 quarts daily - this is important because the casein curds that form in the abomasum will be slowly broken down by enzymes and released gradually into the small intestine. In comparison, directly after feeding all the whey protein floods into the small intestine - this raises the question for me about the availability of protein and energy over the 24-hour feeding period. 

2. under this condition - this volume of milk (6.3 qts) is estimated for a 95lb. calf to support 1.4 pounds average daily gain under no temperature stress (60 F and higher). At moderate temperature stress (40F) this projected gain drops to 1.3 and at  winter temperature stress (20F) estimated gain drops to 1.0 pounds per day. The growth-limiting nutrient here is energy, not protein.

If these calves are going to double their weight in 2 months (56 days) they need to average 1.7 pounds daily gain. Six quarts of milk, especially in cold weather, are not going to provide enough energy for this gain. 

Overall, if the dairy's calf rearing goals are solely to keep the calves alive and moderately healthy through the milk feeding phase with limited growth until their rumen develops enough for them to live on a grain mix, then a once-a-day milk (not milk replacer) feeding program will work about as well as a twice-a-day feeding program under conditions of limited environmental stress.

Reference: Saldana, D. J., C. M. Jones, A.M. Gehman and A. J. Heinrichs "Effects of once- versus twice-a-day feeding of pasteurized milk supplemented with yeast-derived feed additives on growth and health in female dairy calves." Journal of Dairy Science 102:3654-3660 April 2019.

Genomic evaluation for calf wellness traits in Holstein cattle

Here is the summary statement by the authors:

"The results [of this study] indicate direct evaluation of calf wellness traits under a genomic threshold model is feasible and offers predictions with average reliabilities comparable to other lowly heritable traits."

Well, it sounds like although heritability for calf wellness is on the low side it is measurable.

Let's keep this idea in the back of our minds as a possible management tool in the coming decade.

Reference: Gonzalez-Pena, D. and Others "Genomic evaluation for calf wellness traits in Holstein cattle." Journal of Dairy Science 102:2319-2329

Thursday, March 14, 2019

Do antibiotic residues in milk effect dairy calves?

The three characteristic studied in this work were:
  1. growth
  2. ruminal fermentation
  3. microbial community
Calves were studied up to 35 days of age. Half of them receive antibiotic- free milk [FREE] while the other half received milk with antibiotics added to simulate residues [ANT].

No differences in:
(1) starter intake,
(2) body weight,
(3) withers height,
(4) body length,
(5)  heart girth, and
(6) average daily gain. 

In the rumen the ANT calves had a higher acetic acid concentration (probably tied to antibiotics changing the microbial profile). Certain papillae were longer in the ANT group compared to the FREE calves. 

There were very few effects on the overall microbial communities in the rumen.

So, until we get more information I am not going to worry too much about low levels of antibiotic residues in waste milk fed to calves.

Reference: Li, J.H. and Others, "Effect of antibiotic residues in milk on growth, ruminal fermentation, and microbial community of preweaning dairy calves." Journal of Dairy Science, 102:2298-2307

Monday, March 4, 2019

Hard Calving: Impact on Calves

The March 2019 issue of the calf management newsletter, "Hard Calving: Impact on Calves," is now posted at the website.

The key points: 
·        Stress at calving: impact on calves
·        Managing stress at calving: importance of timely intervention
·        Managing stress at calving: matching intervention technique to cause of dystocia
·        Managing pathogen exposure

The url is