Cryptosporidia and Calf Health

 

In the December 2012 issue of the Journal of the American Veterinary Medical Association research was reported on the connection between cryptosporidiosis and how much the calves were fed. (Ollivett, T.L. and Others, "Effect of nutritional plane on health and performance in dairy calves after experimental infection with Cryptosporidium parvum" JAVMA 241:1514-1520)

"After a pathogen challenge, calves maintained hydration, had faster resolution of diarrhea, grew faster, and converted feed with greater efficiency when fed a higher plane of nutrition."

 

In a nutshell the two feeding programs with non-medicated milk replacer were (a) 20-20 m.r. mixed at 15% solids fed 2 quarts twice daily and (b) 28-20 m.r. mixed at 15% solids fed at 3 quarts twice daily first week and 4 quarts  twice daily for the next two weeks. 

 

Points of interest for me:

• Shedding - calves were  handled to prevent natural exposure to Cryptosporium parvum. They were experimentally exposed at their 5th feeding on day 3. Shedding started by four days after exposure. Peak shedding occurred on average on eight days after exposure.  Where we have natural exposure at birth these data suggest we should expect shedding to start around 4 days of age and to peak around 8 days of age.
• Diarrhea - About one-third of the calves did not have diarrhea. However, about one-third of them had severe diarrhea. Not all calves will respond to a crypto infection the same way - we need to watch these 4 to 8 day old calves very carefully in order to provide appropriate and timely care.
•  Rate of gain - the calves on "normal" feeding program either stood still or lost weight at the end of 3 weeks. The calves on the high or intensive feeding program ate their way through the infection and averaged just under a pound a day gain at the end of 3 weeks. Well-fed calves can gain weight during the first three weeks of age in spite of cyrptosporidiosis.

 

A calf with low immunity

Here is today's question from a dairyman in Italy:

"I'm starting to test with the refractometer the claves after birth when I find a low level there's something I can do to the calves for help them?"

 

Here's today's answer:

• For the individual calf with average cash value with a low BSTP reading (already several days old) there is nothing practical that can be done. If the calf is worth $1,000's, yes IV antibody serum could be used, but for the average calf the game is over, done. 
• With my own calves I bled all the calves. And, for BSTP values less than 5.0 I always marked both the calf and her hutch. A tail crayon marker on her forehead and red clip-on cow tag at the front of her individual hutch. That reminded me and everyone else that provided care that she was very vulnerable to clinical infections.
• Every time she was fed (milk, water, grain) and bedded she received a thorough visual examination. If she stuttered (a little slow getting up at feeding time, slow in drinking her milk) I would check her out after I finished caring for the other calves. 
• The herd veterinarian had prescribed a special treatment protocol for these low BSTP calves that we tried to follow without exception.
• I fed these vulnerable heifers to appetite - as much as they wanted to drink at each feeding - I know this was extra work at feeding time but overall it was less work that having them get sick. I felt that the extra energy and protein helped them mature their own immunity more rapidly than if I limited their intake. 

So, the bottom line is keep track of these vulnerable girls and be prepared to step in to keep them healthy.

Just a technical note here - Individual BSTP values can be vulnerable to mis-interpretation. BSTP values are best interpreted on a group basis - for example, 10 or 12 at one time - that will give a "herd" profile of what the colostrum management program is accomplishing.

 

Thawing Frozen Colostrum

Question from client: "What do you think about using a thermostatically-controlled water bath (e.g., turkey roaster) set at 105F to thaw colostrum?

Answer:

Let's review what we are talking about in on-farm terms. You take a turkey roaster out to the barn utility room. Fill it about 3/4 full of water (any more water and it runs over when you put 4 quarts of frozen colostrum in it to thaw). Plug it in and set the thermostat for 105F (use 105 in order to get thawed colostrum at calf-feeding temperature). If you are going to do this I recommend having a small rapid-read thermometer available to measure water temperature - most of the roasters do not have marked temperature settings below 150F.  If you have a probe-type thermometer press it through a 2" square of "Styrofoam" so it can float in the water. 

 

Remember thermostatically-controlled water bath units are not created equally. Look at the electrically specifications plate. It should list the wattage.  Higher wattage units, while more expensive, may maintain water temperature better than those with limited heating ability. Units with greater water volume may be able to thaw the colostrum more quickly than smaller ones.

 

You put 4 quarts of frozen colostrum into the water bath. Now, things get more complicated. If you have frozen the colostrum in freezer-quality self-sealing plastic bags at the rate of 1 quart colostrum in 1 gallon bag, pressed out the air and frozen the bags in a flat position you are placing 4 of these thin bags into the water. Outcome? In about 20-30 minutes expect the colostrum to be slush.

 

If you have frozen the colostrum in 2-quart plastic bottles expect to wait several hours before you can pour the contents into nursing bottles for further warming. If you have frozen the colostrum in 4-quart batches in gallon containers - well, I don't want to even guess on thawing time.

 

Advantages? 

1. You don't have to worry about overheating colostrum and destroying antibodies.

2. Less time spent monitoring the thawing/heating process. No time spent dumping and refilling a bucket with 125-130F water.

 

Disadvantages? 

1. Thawing time is much longer than if you use 125-130F water.

2. Because of long thawing and warming times the chances of not monitoring the thaw/warm process closely go up. There is a higher risk of leaving colostrum at temperatures in the "rapid-growth" range increasing the changes of having high bacteria count. 

 

If you have experience with this method of thawing/warming take a few minutes to drop me an e-mail.

Gone to hell in a handbasket

 Another saying for this situation is, "The wheels fell off the wagon."

Everything is going along great. Bacteria counts in colostrum  way below thresholds. Blood serum total protein values look good - well under 5 percent below 5.0. Treating two out of the 140+ calves with electrolytes. No calves currently being treated for pneumonia. Have not lost a calf since November.

WHAM!  Within five days we are treating the better part of a whole row (15 calves) for scours. Three dead calves in the past five days.

What to do next?

Choice #1: Chicken Little response - The sky is falling! The sky is falling! Engage in lots of finger pointing, casting blame on anyone and everyone. Not my favorite choice.

Choice #2: Pound on my favorite nail - assume that everytime something like this happens the cause is the same. Take out my favorite tool, a hammer, and pound on my favorite nail. For example, jump on the persons feeding colostrum and hammer away on feeding time and quantity fed. Still not my favorite choice.

Choice #3: Review the list of factors most likely to be connected with scours and check out each one. Start with calving pen management, go on to colostrum management, on to calf housing, on to feeding, and so on. Clearly, this is my choice. This process takes time and persistence; not a lot of fun.

In the case I am working on one of the factors was bedding. The summer protocol of using 1/2 a small bale of straw as the initial hutch bedding continued to be used as fall and winter came on. As long as the weather remained mild this practice did not stress calves too much. When a ten-day long cold snap arrived (highs in single digits, lows below 0F at night) hypthermia began to stress out young calves. Their ability to prevent clinical infections dropped off. Scours treatment rate jumped up with the weakest calves unable to maintain core body temperatures.

Most likely solution? Go back to using a full bale of straw to prepare hutches for calves. Be sure calves are "fluff dry" before they go out into the hutches.

Please don't give into the impulse to shout, "The sky is falling."

The greater the time with the dam, the greater the pathogen load in the calf gut

We have known for some time that the longer newborn calves spend in the company of adult cows the greater the risk for scours in the next week or two of life.

In a study just published in the Journal of Dairy Science researchers analyzed fecal samples from 382 calves from 100 farms. (JDS 96:1203-1210 D. Klein, and others "Prevalence and risk factors for shedding of thermophilic Camppylobacter in calves with and without diarrhea in Austrian dairy herds.")

"To define control strategies to reduce Campylobacter in calves, we identified on-farm risk factors." One of the four risk factors identified was "time of cow-calf separation following birth."

Findings?  "Herds in which calves were left with their dam for more than 1 hour had a 2.6 higher risk of being Campylobacter positive than herds in which calves were separated from the cow immediately after birth." (p<.05)(p1205). This finding held up regardless of whether or not the herd had been identified as having a calf diarrhea problem.

Bottom Line? The longer calves spend in the company of adult cows (including the dam) the higher the exposure to all pathogens (bacteria, viruses, parasites).

My rule of thumb is to let the calf remain with the dam as she licks it off. As soon as the calf can stand and starts to walk, out she comes! I feel comfortable using behavior as a guide to remove the calf rather than using a specific time.

Freezing Colostrum

While at a two-day dairy producer conference in Minnesota this past Thursday and Friday I was asked about frozen colostrum.

After asking a couple of questions for clarification of the producers' questions I discovered the real question was "What is the best way to THAW colostrum?"

  

The producers already knew (1) that it was possible to freeze colostrum without damaging the antibodies and (2) that frozen colostrum could be stored for a long time without damaging the antibodies. They also knew that they did NOT like to thaw frozen colostrum.

As the discussion progressed I discovered that the most common way to package colostrum for freezing was in a rigid plastic container such as a two-quart nursing bottle, a two or four-quart plastic jug similar to those in which fresh fluid milk is sold in markets. 

So, I stopped my planned presentation and told them this:

• Make every effort to harvest colostrum without inoculating it with bacteria.
• Check for quality before freezing - no need to freeze low quality (low concentration of antibodies) colostrum.
• Chill the colostrum to 60F (16C) before it goes into the freezer - this slows bacteria doubling to once every 2.5 hours rather than once every 20 minutes at cow-body temperature.
• Package the colostrum in self-sealing freezer-quality plastic bags - load 1-gallon bags with just one quart of colostrum.
• Freeze these bags in a flat position - think of making "leaves" of colostrum.

Then, I recommended for thawing:

• Use a water bath with water between 120 and 130F - not too hot to dip your fingers into it.
• If you put 4 of the flat plastic bags containing 1 quart each into a five-gallon bucket of 130F water it is okay to dump the water after 5-7 minutes and refill with more 130F water.
• Expect the colostrum to turn into slush in 10-14 minutes and be ready to feed at 105F within 20 to 25 minutes.

If you pour the colostrum into a nursing bottle for final warming try snapping on a nipple and inserting a rapid-read thermometer through the vent hole in order to monitor warming.                        
For a quick check list on storing colostrum Click Here .

Yet another link to visit

 

If you are into cold and crisp this is your day in western NY State. Currently 5F with wind chill of -19F. Made me think of the newsletter I read yesterday. 

 

The January news from MilkProduction.com has a nice summary of ideas for cold weather care for calves. 

Click Here  to go to this issue.

You may want to check out this resource on calf blankets: Blanket Link

 

Enjoy.