Thursday, October 11, 2018

Why Would Milk Feeding Method for Calves
be Related to Rate of Growth?

In a US national study of dairy heifer growing practices we find these facts:

                                                    Calves by Average Daily Gain(%)
Feeding method               Poor (<1.4#/da)   Fair (1.4-1.8#/da)   Excellent (>1.8#/da) Total

Bucket/ pail only                     23                       37                           40                            100%
Bottle & Bucket                      32                       35                           33                             100%
Bottle only                              42                       36                           22                             100%

To put the rate of gain in perspective let's add that in order to double birth weight in 8 weeks (56 days) a 90# calf needs to gain 1.6 pounds a day. If her average gain is 1.8 pounds a day for 56 day she will gain a total of 101 pounds - that is really good growth.

So, why is the percent "Poor" so much higher for bottle feeding compared to the other two methods?

This research was not set up to answer this question. Let's do some guessing.

Many of my clients that feed with buckets have "step-up" milk feeding programs. They start calves at 4 quarts a day (divided into 2 feedings). As soon as practical they ramp up milk volume with a goal of being at 8 quarts a day by 10 15 days of age. Most of these operations also have a "step-down" weaning process rather than just quit milk feeding "cold-turkey."

What happens with bottle feeding? Well, the traditional milk feeding bottle has a 2 quart capacity. The calves get fed a bottle twice a day. That sets an upper limit of 4 quarts a day. What are the chances that these calves will be in the "poor" (<1.4#/da gain) category? I am guessing the odds are pretty high - especially if freezing temperatures prevail during the milk feeding period.

I am guessing that the equation "dry matter intake drives growth" applies here. Bucket feeding provides the flexibility to easily increase volume of milk fed well above 4 quarts a day. Few calf operations have the ability to feed with 2 and 3 and 4 quart bottles as the calf grows from birth to weaning.

By the way, season of the year [environmental temperature] was associated with rates of gain - hotter weather depressing gains, cooler weather showing higher gains. In calf hutches, during freezing weather with my intensive-fed calves average daily gain was usually between 1.9-2.1#/day. During the hottest summer months our average daily gain was usually between 1.6-1.8#/day.

My experience with using both bottles and buckets:

I fed my calves with both bottles and buckets. Bottle fed for about the first 4-5 days (until nursing strongly). Switch to bucket - lots of wet clothing and spilled milk along here - I had one Brown Swiss calf that never did drink out of bucket.

Ramp up milk replacer (15% solids, 28-20) volume to match appetite with the goal of 4 quarts twice daily. At 5 weeks any calf eating one pound  (454g) of calf starter grain (20% protein) every day lost her PM milk replacer feeding - she had to "starve" on only 4 quarts (3.8L) a day.

Most of these calves were consuming more than 4 (1.8kg) pounds of grain daily by the time they were 7 weeks old. Somewhere between 45 and 49 days they began receiving a small "handful" of hay in their grain bucket three times a week. Most were full weaned around 50-52 days. Moved to group pen (5 to a pen) around 60 to 65 day (depended a lot on pressure for empty hutches).

Reference: Shivley, C. B. and Others, " Preweaned heifer management on US dairy operations: Part 6. Factors associated with average daily gain in preweaned dairy heifer calves." Journal of Dairy Science 101, 9245-9258. October 2018

Wednesday, October 10, 2018

Our Dairy Does Not Have
Cryptosporidum or Giardia!

In 2014 the National Animal Health Monitoring System completed a calf study involving 104 dairy operations in 13 states. This was an 18-month longitudinal study involving 2,545 heifer calves. Holstein calves made up 89% of the population. By herd size, the study included:
  • Small (30-99cows)            20%
  • Medium (100-499 cows)   32%
  • Large (500+ cows)            48%


They did fecal testing to determine the presence of both Cryptosporidium and Giardia.

Do you really believe that your dairy does not have either of these parasites?

Guess again. Presence was - percentage of farms with parasite present:

94% Cryptosporium


99% Giardia


Or, on the basis of calves that were fecal sampled, percentage of calves with parasite present:

43% Cryptosporidium

30% Giardia

Important to note - these were not clinical cases of infection. These laboratory results were just presence/absence of parasites.

Reference: Urie, N.J. and Others "Preweaned heifer management on US dairy operatons: Part 3. Factors associated with Cryptosporidium and Giardia in preweaned dairy heifer calves." Journal of Dairy Science 101:9199-9213 October 2018.

If there are clinical symptoms here are a two basic resources on these parasites.

  • click  HERE for basic resource on Cryptosporidium - or this is the URL http://atticacows.com/library/newsletters/CryptosporidiumparvumN18125_1.pdf

  • click HERE for basic resource on Girardia - or this is the URL http://atticacows.com/library/newsletters/GiardiaUKR17108.pdf



Monday, October 8, 2018

Do Everything Right and Still Get Failures!
Colostrum Management

In 2014 the National Animal Health Monitoring System completed a calf study involving 104 dairy operations in 13 states. This was an 18-month longitudinal study involving 2,545 heifer calves. Holstein calves made up 89% of the population. By herd size, the study included:

  • Small (30-99cows)            20%
  • Medium (100-499 cows)   32%
  • Large (500+ cows)            48%
They collected information on colostrum management:
  • Quality of colostrum fed
  • Quickly - time after birth when colostrum fed
  • Quantity of colostrum fed
What did they find?

  • When calves received excellent management (high quality, fed quickly, volume of 10% or more birth weight) - still 14% still had passive transfer failure (<10g/L).
So, how come this finding?
  1. One possibility is that the subject farms lied - they reported what the farm protocol was rather than what actually was being done. But, there were many farms and many calves - so maybe not such a good explanation for 14% PTF.
  2. A second possibility is sampling and testing error. Only one blood sample was taken from each calf with considerable variation in days between first colostrum feeding and when the blood was drawn. This could account for some of the failures but still 14% is lot to attribute to errors.
  3. A third possibility is genetic variation. Some calves have genetically determined ability to absorb antibodies very efficiently while others are at the other end of the spectrum - poor absorption ability. I not sure how I would go about measuring this. But, given natural variation on all other traits this might be a viable alternative. 
Where do I come down on this question?

While the first and second reasons might account for one or two percent of PTF it is my opinion (note lack of scientific evidence) that genetic variation could play a big role here.

On one hand, as calf care person it is not reasonable to beat ourselves up over wide variation among calves in passive transfer of immunity.

On the other hand, I have a client (130 calves on milk) whose colostrum feeding protocol includes feeding only Brix 23 or higher colostrum as first feeding, nearly all calves receive first feeding before 4 hours after birth and the calves receive 4 quarts at birth, 2 more quarts 6 hours later and another 2 quarts 6 hours after that. Their PTF rate last month (<5.0 g/L) was 5% with an average BSTP of 6.4 g/L.

Reference: Shivley, C.B. and Others "Preweaned heifer management on US dairy operatons: Part 2 Factors associated with colostrum quality and passive transfer status of dairy heifer calves." Journal of Dairy Science 101:9185-9198 October 2018.

Wednesday, October 3, 2018

Is "Waste Milk" Good for Calves?

The October issue of the calf management newsletter is now posted at www.atticacows.com.

The content summary is:
  • What is “Waste Milk?”
  • Quality characteristics of nonsaleable milk
  • Strategies for getting the most growth from nonsaleable milk feeding
  • Special considerations for weaning when feeding nonsaleable milk

You can access the newsletter, just click HERE or if that does not work paste this URL in your browser
http://atticacows.com/library/newsletters/CEOctober2018.pdf


Monday, October 1, 2018

Watch Out for Poor Quality Colostrum

In 2014 the National Animal Health Monitoring System completed a calf study involving 104 dairy operations in 13 states. This was an 18-month longitudinal study involving 2,545 heifer calves. Holstein calves made up 89% of the population. By herd size, the study included:
  • Small (30-99cows)            20%
  • Medium (100-499 cows)   32%
  • Large (500+ cows)            48%


They evaluated colostrum fed to calves. Using the threshold of 50g/L IgG based on 2,263 individual colostrum samples they found that 23 percent of the samples failed. 

That same information stated another way, nearly one calf out of four was fed inferior quality colostrum! I guess we should not be surprised to learn that so many preweaned calves have scours and pneumonia.

Based on the number of dairy operations, only 17% of the 104 operation had 90 percent of their colostrum testing at or above 50g/L. Ten percent of the farms (about 11) did not have even 1 sample that was acceptable (at or above 50g/L). Did that fact hit home for you? All of the calves on these farms (10% of the total 104 operations) were fed inferior quality colostrum.

Test - don't Guess! 

If you are not already evaluating your colostrum quality before using it for first feeding of newborn calves now is the time to make the change. 

Click HERE to go to a guide for using a Brix refractometer to assess colostrum quality. [If the link does not work here is the URL http://atticacows.com/library/newsletters/ColostrumTestingRefractometerR18119.pdf] Both optical and digital refractometers are available for on-farm use. In this study of 104 dairies only 17% were using a Brix refractometer to evaluate colostrum quality.

Note that other colostrum resources are at www.calffacts.com - just scroll down to the word colostrum.