Wednesday, September 27, 2017

Nursing Consumption of Colostrum

In a small sample (N=44) of Holstein calves with unassisted births the colostrum consumption was measured. Their average birth weight was 42.8kg [94lbs].

The dams were milked at  the next regular milking shift (2x) and the calves were fed the colostrum from their dams. This resulted in intervals from birth to colostrum feeding time that varied from 20 minutes to 17.8 hours.

All colostrum was fed warm from the dam in a nipple bottle. All the calves were offered 4L (4.2qt) initially. If they drank all 4L then 2 more liters were offered.

HOW MUCH DID THEY DRINK VIA NIPPLE?

"Eighty-four percent consumed >3 L of colostrum. Of the calves consuming <3 L of colostrum, the average colostral intake was 2.7 L [2.9qts] and ranged from 2.4 L [2.9qt] to 2.7 L [3qt]." p6610

The average consumed was 3.6 L [3.8qt] with a low of 1.5 l [1.6QT].

These data support my experiences feeding colostrum with a nipple bottle. For my Holstein calves with an unassisted birth fed in the range of about 2 to 10 hours after birth well over half of them drank two full 2-quart bottles of colostrum and many more drank one full bottle and half or more of the second one.

I used the time while bottle feeding as an opportunity to do a health and vigor assessment on calves. I have to add that on one day when I also was trying to do regular calf feeding and we had 13 newborns I did not bottle feed colostrum to all of the newborns.

A side note on bottle feeding. I always had two nipples with me. One nipple had an "average" opening - that is, small enough to prevent colostrum from running out of the bottle when held upside down yet large enough to permit easy flow for a vigorously nursing calf. One nipple had a "small" opening - that is, small enough so that a calf had to work at getting colostrum from the bottle.

Why two nipples? Most, probably 9 out of 10, calves did just fine with the "average" nipple. However, a small minority had choking problems - as a newborn they could not swallow well enough to clear the back of the mouth consistently when breathing. I found the "small" nipple was quite effective in solving this issue. And, it prevented aspiration of colostrum. My part-time helpers called them the "fast" and "slow" nipples.

Reference: Osaka, I. and Others, "Effect of the mass of immunoglobulin (Ig)G intake and age at first colostrum feeding on serum IgG concentration in Holstein Calves." Journal of Dairy Science 97:6608-6612 2014


Monday, September 25, 2017

How Many Antibodies We Feed End up in the Blood?

A standard method is used to estimate the proportion of antibodies fed to a calf that end up in her blood. It requires knowing:
  • calf body weight
  • volume of colostrum fed
  • IgG concentration in colostrum
  • IgG concentration in blood serum
100 calves were in the study. "After a normal calving, the heifer received either 4 or 5.6L of colostrum within 4 hours of birth, [a sample was taken of the "as-fed" colostrum] and a blood sample was collected between 24 and 36 hours after birth." p3282

The measure is called "apparent efficiency of absorption" or abbreviated as AEA.

The AEA values:
  • Average = 28.1%
  • Median = 27.5%
  • Minimum = 7.7%
  • Maximum = 59.9%
Most of the calves (70%) had values between 21% and 40%.

BOTTOM LINE? Using "average" conditions, in order to end up with at least 5g/dLantibodies  in the calf's blood we need to feed roughly 180g total in the first feeding (28% AEA). [This uses 5g/dL as an acceptable threshold for successful passive transfer of immunity. Excellent quality colostrum (80g/L) will deliver this in 2.7 quarts. Poor quality colostrum (30g/L) would require 7 quarts to equal 200g of antibodies.]

As a side note, one of the dairies fed 4 quarts as first feeding within 4 hours of birth and then an additional 2 quarts before 12 hours of birth.

The two- feeding protocol (total of 6 quarts) resulted in both an increase in AEA and a 68% increase in circulating antibodies in the blood compared to the single 4-quart feeding. These data agree with one of my client dairies that has a two-feeding colostrum protocol - they have well over 90% of the calves testing at 5.5g/dl blood serum total proteins.

Reference: Halleran, J. and Others, "Short Communication: Apparent efficiency of colostral immunoglobulin G absorption in Holstein heifers." Journal of Dairy Science 100:3282-3286 September 2017


Thursday, September 21, 2017

More Data on Variation Among Jersey Calves for Passive Immunity

Blood samples from ninety-seven 1 to 3 day-old Jersey calves from a three-state project in the United States of America were used to assess successful passive transfer of immunity from colostrum.

Overall, 90% of the calves had successful passive transfer of immunity.

Using blood serum total protein as a measure (cut point for success was 5.5):
Average     = 5.8
Minimum  = 3.7
Maximum = 8.4

Using Brix as a measure (cut point for success was 7.3):
Average     = 8.9
Minimum  = 6.5
Maximum = 12

The objective of the study was to validate a cut point for Jersey calves using the Brix refractometer. In contrast to the Holstein standard of 7.8, this project suggests using 7.3 as the threshold for measuring successful passive transfer of immunity for Jersey calves. 

Reference: McCracken, M.M. and Others, "Technical Note: Evaluation of digital refractometers to estimate serum immunoglobulin G concentration and passive transfer of Jersey calves." Journal of Dairy Science 100:8438-8442 October 2017.

Tuesday, September 19, 2017

Measuring Colostrum Quality

Measuring colostrum quality is a best management practice. It's not difficult to do and the equipment is inexpensive. Guidelines for using a Brix refractometer are found HERE.

A recent report on a survey of dairy farms in Michigan and Ohio included information from 449 farms (56% <100 cows, 39% between 100-499 cows and 5% 500 cows and greater). 

They were asked if they measured colostrum quality before feeding it to newborn calves. 

Results? The percent measuring were:

>500 cow herds      = 25%
100-499 cow herds = 18%
<100 cow herds      = 3%

These same producers were asked this question:
"Measuring colostrum quality is useful to make decisions on feeding calves colostrum: (responses were Strongly agree, somewhat agree, neither agree or disagreee, somewhat disagree, strongly disagree).

Of the 43 producers that regularly measure quality 41 agreed with this statement - their attitude and behavior matched. 

Of considerable interest to me was that finding that 39% of the farms NOT measuring colostrum quality agreed that measuring quality is useful in making decisions on feeding calves colostrum. 

Of those of the opinion that measuring colostrum quality is not useful, 53% also felt that the process of measuring quality was time consuming. That makes me wonder if they had actually observed the use of a Brix refractometer for colostrum quality measurement.

Reference: Pempek, J.A. and Others, "Dairy calf management - a comparison of practices and producer attitudes among conventional and organic herds." Journal of Dairy Science 100:8310-8321.

Friday, September 15, 2017

Every Time I Try Feeding My Calves More 
They have Scours

This past week I talked with some calf care folks. One of the practices I recommended was feeding calves more than the out-of-date four quarts a day of 20-20 milk replacer. 

The reaction of some folks was captured in the words of one calf care person, "Every time I try what you suggest of feeding more, my calves have scours."

So, I spend about half an hour explaining that we control the conditions that either increase or decrease the chances of calves having diarrhea when fed more that 4 quarts of milk/milk replacer a day. The greater the number of best management practices we follow the lower the opportunity for calves to have diarrhea.

You may want to review this list of 10 factors that I think probably are most likely to make a difference in how calves respond to increased feeding rates. Click HERE for the list (2 pages) or if the link does not work for you try pasting this link in your browser:
http://www.atticacows.com/library/newsletters/FeedingMoreMilkwithoutScoursR1745.pdf 




Thursday, September 14, 2017

How Often Do I Need to Check My 
Colostrum Bacteria Count?

It depends. Well, that is not a very helpful answer.

The national Dairy Calf and Heifer Association Gold Standards thresholds for bacteria counts in colostrum are <5,000cfu/ml coliforms and <50,000cfu/ml total plate count. For an expanded discussion of bacteria in colostrum click HERE

If the farm has not sampled and cultured "as-fed" colostrum for bacteria you can find a sample collection protocol HERE (or in Spanish HERE). I like to see a minimum of 5 samples each time. If the dairy is large enough to have different shifts of workers handling and feeding colostrum then 2 samples from each shift is a good idea.

When the results come back compare them to the standards above. By the way, when ordering the culturing from a lab you often have to specify that you want both speciation (which bacteria are present) and quantification (how many of each species). I usually tell the lab I do not want them to use techniques to get exact counts when the number of colonies on the plate are too numerous to count (often abbreviated as TNTC).

If the farm sample results look good (below standards) I recommend extending the sampling interval to every 3 months. This quarterly interval follows the seasons of the year along with changes in labor availability that go with cropping cycles. 

If the farm sample results contain one or more high count samples I recommend taking corrective action and resampling each month until the results come back in below the farm's goals. If coliform counts are high you may want to review my checklist for reducing these counts (click HERE).

Monday, September 11, 2017

Passive Transfer Failure: It's Hard to Hit Zero!

In research study Holstein heifer calves received their first colostrum feeding at 4 or less hours after birth. They were fed 4.2 quarts of colostrum in one feeding that averaged 58g/l quality - so on the average they received around 240g of Ig's. 

In spite of this exemplary care they still had 2 percent passive transfer failure. The average efficiency of absorption (percent of antibodies fed that end up in the calf's blood) was around 23 percent. However, the range of efficiency was from less than 10 to over 50 percent. 

Another part of the study included calves fed 4 quarts as first feeding (less than 4 hours old) and another 2 quarts before they were 12 hours old. This colostrum averaged nearly 70g/l. With the combination of two feedings of excellent quality  colostrum (added up to 390g of Ig's) a higher level of passive transfer was  achieved.   

Bottom line? If you have a calf now and then that has passive transfer failure don't beat yourself up over it. Genetics always will play a role when you roll the dice and once in a while you will lose. 

Despite the wide range in apparent absorption efficiency demonstrated in this study it was clear that feeding 4 quarts (10% body weight) of good quality colostrum within 4 hours of birth will result in an excellent program for calf immunity. Other research has shown that at this volume similar results will be achieved with either one or two feedings and feeding either by bottle or tube feeder. 
[Click HERE for more on this.]  

Reference: Halleran, J. and Others, " Apparent efficiency of colostral immunoglobulin G absorption in Holstein heifer." Journal of Dairy Science 100;3282-3286. Osaka, J. and Others, "Effect of mass of immunoglobulin intake and age at first colostrum feeding on serum IgG concentration in Holstein calves." Journal of Dairy Science 97:6608-6612.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      

Wednesday, September 6, 2017

Guidelines for Storing Colostrum

The September 2017 issue of the calf management newsletter offers guidelines for doing a good job of storing colostrum. Whether refrigerated or frozen, having a backup to fresh colostrum is a best management practice.

The key points are:
·       Start with clean colostrum
·       Reduce growth of bacteria
·       Monitor effectiveness of storage methods

Enjoy.

Friday, September 1, 2017

More on Transition Milk
"Transition Milk is Too Valuable to Sell"

This article [click HERE to go to it online] by Maureen Hanson quotes Dr. Jeremy Schefers from the University of Minnesota Veterinary Diagnostic Laboratory, If the link does not work, try this URL
http://www.dairyherd.com/advice-and-tips/calf-and-heifer/transition-milk-too-valuable-sell 

He is quoted as saying that transition milk is easily worth $30/gallon or $300/cwt because of its value in  promoting good gut health. 

This blog reinforces my transition message in my June 15th Blog on the value of second milkings - about half of the samples tested 50g/L (that is the national threshold for acceptable first feeding colostrum).