Tuesday, December 17, 2013

Hard Calving and Cold Weather
 Calves experiencing difficult deliveries may need extra attention in cold weather conditions. Christine Murray, University of Guelph, presented " Newborn Calf Vitality: Risk factors, characteristics, assessment, resulting outcomes and strategies for improvement" at the Calf Congress 2013: Growing the Next Generation, RIT Inn and Conference Center, Rochester NY December 4-5, 2013.
As part of her presentation Ms. Murray talked about problems with thermoregulation among dystocia or hard delivery calves. She observed these calves may experience:
  • Depending on the degree of stress, calving environment and season of birth, maintaining homeostasis can be challenging.
  • Decreased available energy needed for the mobilization and metabolic activity of brown adipose tissue [fat] during non-shivering thermgenesis.
  •  Reduced muscle tonicity, preventing shivering.
  • Less able to withstand cold stress.
 Thus, we can conclude that extra measures to get these dystocia calves dry and into a modified (warmer than outdoors) environment should improve survival rates. Let's think about:
  • Getting the calf dry. For a resource on drying calves, click HERE
  • Having available a space that is above freezing - maybe a hutch with a heat lamp, a purchased box with a heater and fan - to house the calf for at least the first few hours after birth.
  • Using a calf blanket. For a resource on calf blankets, click Blankets
  • Feeding plenty of high quality WARM colostrum within the first two hours after birth.
  • Bedding her pen/hutch with plenty of long straw so she can nest. If in an open pen setting, providing something like a small square bale of straw to nest against.
  • Feeding an extra meal for the first week to push up milk intake by 20 to 30 percent.
 These few extras may make the difference between life and death for these thermoregulation-challenged calves. 

Thursday, December 12, 2013

Goals for Bacteria in Pasteurized Milk
What should be our goal for level of bacteria in pasteurized waste milk for preweaned dairy calves?  Zero? 100,000 cfu/ml?
In his presentation, "Calf Raising - A Systematic Approach to Health," Dr. Simon Peek (Univ. Wisc. School of Vet. Med.) listed several goals for bacterial quality control.
[Peek, Simon, "Calf Raising-A Systematic Approach to Health," proceedings of Calf Congress "Growing the Next Generation" December 4-5, 2014 RIT Inn and Conference Center, Rochester, NY, pp48-60.
These goals are:
                                                   Goals (cfu/ml)
Sample               Total Bacterial          Total Coliform          Total E. coli              
Type                   Count                        Count                        Count
Colostrum          <100,000                   <10,000                    <1,000
Waste milk        <500,000                   <200,000                   <1,000 
Pasteurized        <20,000                     <1,000                       <100
Waste Milk
Milk Replacer   <10,000                     <1,000                       0
In my consulting practice I use somewhat more conservative goals that I have identified as associated with superior calf health. 
They are (Leadley's on-farm goals):
  Goals (cfu/ml)
Sample               Total Bacterial          Total Coliform          Total E. coli              
Type                   Count                        Count                        Count
Colostrum          <50,000                    <5,000                       <500
Waste milk        <500,000                   <200,000                   <1,000 
to be pasteurized
Pasteurized        <5,000                       <500                         0
Waste Milk
Milk Replacer   <5,000                       <500                         0
Bottom Line?
If you do not monitor by bacteria culturing on a regular basis you are not managing this important variable affecting calf health [regardless of the goals]. 
The Most Common Mistake in Mixing Milk Replacer

The most common mistake when mixing milk replacer is to measure out the final volume of water and then add milk powder.
Disclaimer: If you milk milk replacer powder for one calf at a time and each calf consumes the total amount of mixed product, then these comments do no apply to you.

For all of us that mix a large volume of milk replacer and then feed a fixed volume to each calf, this potential error applies to YOU.

I visited a farm yesterday to help confirm that the mixing protocol was correct. Their goal is to feed 15 percent solids. 

Their protocol using a mechanical mixer that both mixes and delivers the reconstituted milk replacer is to add water until they have about one-half of the desired volume. Then they add the total amount of powder for the mix. After this is blended more water is added until the selected mark on the side of the stainless steel tank is reached.

Actual numbers? Run in 35 gallons of water. Add 85 pounds of powder. Blend. Add enough water to come to 65 gallons total mix. 

Total mix weighs 559 pounds (that is, 65 gallons X 8.6#/gallon = 559).
Total powder added was 85 pounds. 
When total powder is divided by total weight (85 / 559) we get .152 or 15.2 percent solids.

Great! Now when they feed 6 quarts of this daily the calves receive just about 2 pounds of solids a day   (6 quarts = 12.9 pounds "as-fed" at 15.2% solids)

The most common mistake in mixing milk replacer?

Measuring the total volume of water equal to the amount of mix desired and then adding powder to that water. What would have happened if this calf care person had not followed the correct protocol? She would have started by filling her mixer with 65 gallons of water. 
Then she would have added the 85 pounds of milk replacer powder. What would have been the result?

Well, she started with 65 gallons of water. At a little over 8.3#/gallon that comes to 542 pounds. Then added 85 pounds of powder. Total weight now is 627 pounds.

When total powder is divided by total weight (85/627) we get 13.5% - not the intended 15% solids. So when she feeds 6 quarts of this 13.5% mix daily the calves receive 1.74 pounds of powder each day.

Does a mixing error make a difference?

So what? There is not much difference between 1.74 and 1.96; only .22 pounds. But, in a week that comes to over 1.5 pounds less feed. 

Tuesday, December 3, 2013

Early Identification of Sick Calves
Donna M. Amaral-Phillips, U. Ky., in the most recent dairy newsletter reminds us of the resource, Early Identification of  Sick Dairy Calves Important to Their Survival and Future Milk Production.
The outline is:
1. Critical control points for colostrum management
2. Identifying potentially sick calves
     a. Step 1: Identify calves needing more careful evaluation at and just before feeding
    b. Step 2: Closer inspection (for calves with potential illness detected through questions
                    answered in Step 1) - with pictures
 3. Electrolytes important for scouring calves
     a. Calf symptoms
     b. Prevention
If you have not been to the University of Ky dairy website try it!

Monday, December 2, 2013

I walked in and the calves all got up!
I was re-reading the paper, "Group Housing and Feeding Systems for Calves - Opportunities and Challenges," written by Bob James and Kayla Machado and presented in March 2013 at the Western Dairy meetings in Reno, NV.
As a result of their study of eleven dairies in Virginia and North Caroline in the summer of 2011 they made this observation about calf behavior:
"When calves are fed twice daily in individual pens, they respond to people entering the barn through increased activity and vocalization. Calves fed via an autofeeder system will not respond to people entering the pen. If a calf does so, it usually means that they have not been trained to the feeder or there is an equipment malfunction." [bold my editing]
When I read this I recalled going into a barn with ad lib acidified feeding stations with the calf manager. When we went into one pen nearly all the calves got up. The care giver immediately said, "Something is wrong." After searching for a few minutes she found that a worker had closed a valve while servicing the feeding equipment and forgotten to open it again to allow the calves to drink.
Much of effective calf management is knowing what is "normal" behavior of calves and recognizing when they are behaving abnormally. This applies to groups of calves as well as individuals. This one of the reasons I encourage managers of group-housed calves to spend time observing their charges - especially the younger ones less that a month old.