Thursday, August 28, 2014

Energy in Colostrum Replacers

In a current article, "6 Tips to consider when shopping for colostrum replacement" by Dr. Tom Earleywine from Land 'O Lakes, published in Progressive Dairyman August 25, 2014, pp 42-44 we find advice on purchasing criteria.

One of the criteria deals with colostral fat. Tom's advice is to look for at least 20 percent fat. For cold weather conditions he suggests using a product that provides at least 100g of fat.

I thought I would check on the products that are sold here at our vet clinic. Neither product gives any information about fat on the outside of the container. I went online. Surely, the information would be there. Well, guess again. I found the fat content for one product online and not the other. Further checking showed that grams of fat is not a common listing. Some products do provide percentage information so with a total dry weight the actual grams of fat can be calculated.

Maybe checking with the sales rep would work. I will try to check with our rep the next time we have contact. 

The basic principle is still valid, however. Try to use a replacer product with enough energy to sustain the calf until the next feeding depending on the environmental conditions. In general, I have clients use a lower energy product during warm weather months (an economy measure) and switch to the higher energy product during cold weather months if they are located in a cold climate.

Wednesday, August 27, 2014

Auto-Feeders Need to be Cleaned, Too

I had the opportunity to observe a auto-feeder representative teach an owner how to run the cleaning operations for an automatic calf feeder. What an education for me!

A recent research report, "Health of dairy calves when using automated feeders in the Midwestern United States", M. Jorgensen and Others, J. Dairy Sci. Vol  97, E-Suppl. 1, p18, abstract # 36, supplied information on the bacteria counts for milk samples obtained from the tube leading to the nipple.

The median (the halfway point between lowest and highest) values for the 38 sample farms were 2,550cfu/ml coliforms and 330,000cfu/ml standard plate count. So, are these numbers good? Or, are they bad?

The upper thresholds I use for milk being fed to calves are 500cfu/ml coliforms and 5,000cfu/ml standard plate count. So, in my opinion these are not good numbers. 

I watched the company rep show the operator how to set up a "cycle-clean" operation. This means detaching the feeder tubes from the stalls and nipples. The tubes are transferred to a station on the machine that will allow the hot detergent wash solution to circulate through the entire system - a rinse cycle is included as well. It looks to me that this is an aggressive cleaning routine that is farm is planning to use twice a week. Some samples sent for bacteria culturing will confirm that is plan is working.

Thus, we conclude auto-feeders need to be cleaned and if one follows the manufacturer's directions they can be kept clean.

Tuesday, August 26, 2014

Where is the Cocciostat?

"How are you controlling coccidia?" That was my question to the dairyman. The answer was, "I have X coccidiostat in the calf starter grain." Calves are housed individually in hutches, grain is replaced daily for younger calves, for older calves the pail contents are checked daily and more grain added is needed so the calves do no run out of grain before the next feeding. Calves have free-choice water. The dairyman said that the pre-weaned calves did not show clinical signs of coccidiosis although they did have some scours among calves three to four weeks old.

With a bit of calculation we determined the volume of calf starter grain the calves needed to consume in order to get protection from coccidia. The only calves eating enough calf stater grain to provide protection were those whose milk replacer ration had been reduced as the first step in weaning. They were about 35 to 40 days of age.

Thus, while the coccidiostat was present the weak link in the protection protocol was the factor of consumption. Given this one route of administration the calves were left unprotected for the first five weeks of life.

Was it valid on this dairy to assume that exposure to coccidia was low enough that none or very few animals would be exposed to the parasite? Without going too many details, let's just say that while a reasonably good job of sanitation was being done in the prefresh housing, calving areas and calf housing my opinion is that many of the calves are receiving an infective dose of both coccidia and cryptosporidia by the time they are a week old. 

We discussed alternative routes of administering the available coccidia-control medications in addition to the calf starter grain. Since the calves are being fed milk replacer the most cost-effective method in this situation appeared to be the addition of a coccidiostat to the commercial milk replacer - a phone call confirmed that their supplier had the product available. 

The lesson here was that just because a coccidia-control medication is present the effective dose may not be available to the population at risk. Don't be lured into thinking that your coccida control program is effective for all the calves at risk just because you have medication in the concentrate or calf stater grain.

Monday, August 25, 2014

Clean Colostrum

I had an opportunity to collect colostrum samples on Thursday last week. One sample was from the collection bucket. The cow had calved about 30 minutes ago - she was up, steady on her feet and was busy licking her calf. After she was restrained the caregiver cleaned up the teats and milked her into a clean collection bucket. After a gallon of colostrum was poured off for feeding the calf I collected my sample from the bucket. A bacteria culture showed 6,500 cfu/ml Staph species.

My second sample one-half hour later was from the same collection bucket (rinsed between cows with warm water and then a quick chlorine solution rinse) for cow #9640. Same routine with cow - udder prep the same. The bacteria culture showed 300 cfu/ml Staph species. 

My third sample was colostrum from the same cow, same collection bucket coming out of the tube feeder. The bacteria culture showed 1,800 cfu/ml Staph species. 

How do these compare to the maximum thresholds I usually use to assess cleanliness of colostrum for feeding newborn calves?

I like to see the total or Standard Plate Count at 50,000 cfu/ml or less and the Coliform count at 5,000 cfu/ml or less. Dr. McGuirk, University of Wisconsin School of Veterinary Medicine, uses thresholds of 100,000 cfu/ml and 10,000 cfu/ml respectively.

These values are very, very low.


Clean teats.
Clean collection bucket.
Clean tube feeder.
If there was inoculation with bacteria, there was no opportunity for growth.

So, feeding fresh colostrum procedures get rated A+.

My next check on this dairy will be to get samples of colostrum that is fed after being frozen, thawed and warmed for feeding.

Friday, August 22, 2014

They Stop Growing

I am looking at heifers in a transition pen. The owner tells me, "When I move heifers into this pen they stop growing. After three or four weeks they seem to take off again."

I checked out the ration for this pen - it is the first pen into which calves are  moved as they come from individual pens after weaning. The ration before the move was calf starter grain and water for one full week after the calves were weaned. The ration in this pen was free-choice haylage topped off with a grower pellet.

The heifers in this transition pen found the haylage quite palatable - they were eating lots of it. Remember, however, that before moving into this pen they had no exposure to any kind of forage, especially this haylage. 

What was going on here? Heifers consuming the haylage for the first week in the pen did not have the appropriate microbial population to break down this fiber source. The haylage just went into the front, turned brown and came out the back - not much nutrition there. Eventually, after a week or two the rumen microbial  population reached a new equilibrium with the digesting microbes matching the dietary content.

So, the heifers were, in fact, put on an involuntary negative-energy ration the first week or two in this pen - they were eating but not benefiting from what was eaten. No wonder they stopped growing. This dairy was fortunate that circumstances did not otherwise stress the calves and they had very few problems with respiratory illness in this pen.

I looked at the older heifers and they appeared to be in good health. However, an opportunity for growth was slipping away from this dairy. They could  have introduced the haylage in the individual pens during the last week calves were housed there. They could have introduced the haylage in smaller amounts in this first group pen - maybe the amount the heifers would clean up in half an hour each day for the first ten days or so before going to free-choice feeding.

Just a thought here - remember that just like mature cows, in these 2-4 month-old heifers we are feeding a rumen, not the animal.
Great Ideas on Pneumonia

In a brief article published in the August 7 issue of Progressive Dairyman, " Defend dairy cows from respiratory disease" (pp 55-56) Dr. Amelia Woolums from the Department of Large Animal Medicaine, University of Georgia, captures the essentials about:
  • Pneumonia in adult cows: How often does it occur and what are the signs?
  • What is pneumonia, and why does it matter?
  • How can pneumonia  be treated or prevented?
She prepared a great summary on vaccinating for pneumonia that was published as a sidebar. 

She says:
"The common respiratory viruses for which vaccine exist in the U.S. include:
1. infectious bovine rhinotracheitis virus (IBR), also known as bovine herpesvirus-1 (BHV-1)
2. bovine respiratory syncytial virus (BRSV)
3. bovine viral diarrhea virus (BVDV)
4. parainfluenza type 3 virus (PI-3V)"

Of special interest to those of us working with calves she notes:
1. Evaluate the proven efficacy of a vaccination.
2. Give vaccines time to protect the animal. The strongest response occurs at least two weeks after the vaccination is given. 
3. For the most reliable protection the calf should receive two doses of the vaccine, separated by approximately four weeks, before they are exposed to infection.

If you missed this article see if you can find the August 7 issue - it's the one showing field work chopping corn on the cover.

Wednesday, August 20, 2014

Surge in Calving, Yet Again

How can a surge in calving be a surprise? The cows have been pregnant for nine months!

A client experienced a challenging situation with the youngest calves in his operation. Lots of scouring among very young calves, some bloating and a few calves died. Their calving rate during July was much higher than the average. They usually have five or six new heifer calves a week.

Surprise, the heifer calves just started coming around the first of July and they didn't stop. Ten one week, eight the next week, ten the next week, agggggggh! What we would give for a bull calf! What felt like non-stop calving, milking colostrum, feeding colostrum, trying to find space for yet another calf.

What happens on your dairy when this happens? Are enough persons cross-trained for these tasks of calving, dipping navels, milking colostrum, feeding colostrum, storing extra colostrum, mixing up colostrum replacer as needed, keeping all equipment for colostrum and milk feeding using the effective cleaning protocols, and on and on? Are there enough hands to do all the jobs at the right time the right way all the time? 

Or, because of the surge of work do folks have to cut corners just to get through the day? Is colostrum fed later than it should be? Do calves receive all their colostrum or "just enough?" Do we skip checking colostrum for quality? Does equipment get "rinsed" rather than cleaned thoroughly? Is a newborn calf left too long in a calving pen? Are we housing newborns in pens that have not been either cleaned or received fresh bedding? Too much to do with too little time to do it?

Surges in calving do not have to be a secret - the cows have been pregnant for nine months. We can prepare for them. You might want to read this issue of Calving Ease that planning works better than muddling through - click here.

Tuesday, August 5, 2014

"Calves with Sam" on Vacation!

Esther and I are off to Paris, France to visit our son's family from August 6 through August 16. Paul is a professor at the University of Paris - South, Anne (a native of France) holds an executive position with a UN agency, two grandchildren are at university.

I'll back posting on Calves with Sam somewhere around August 18. See you then. 

Monday, August 4, 2014

Can Cryptosporidium Exposure Come From Cows?

That question came to my desk this morning. After a couple hours of research using the Internet I came to these conclusions:
  • Yes.
  • However, what little research I could find indicates that only a small  percentage of beef and dairy cows seem to shed crypto oocysts. One study of 43 dairy cows even found none shedding. 
  • Nevertheless, if calves are born in shared calving paddocks or pens even very low levels of exposure to contaminated feces can serve as an infective dose causing cryptosporidiosis.
Many, many studies have documented the shedding behavior of bovine calves with cryptosporidiosis. Given the huge numbers present in a preweaned calf-rearing environment and the low number of oocysts needed for an infective dose we can reliably conclude that reducing the spread of the disease among calves is likely to be the most cost-effective approach to controlling crypto.

So, forget about crypto coming from cows? No, not a good idea. Maintaining clean calving facilities will reduce the probability of those few shedding cows providing a steady supply of infected calves for the calf-rearing housing. 

Friday, August 1, 2014

How Long with Colostrum Keep in the Refrigerator?

This was the question in my e-mail box this morning. In a nutshell this is my reply.

Shelf life of refrigerated colostrum depends on:
  • inoculation level before refrigeration
  • colostrum temperature going into the refrigerator
  • temperature of the refrigerator
  • presence or absence of food preservative
The person asking the question does not have inexpensive access to a lab that can do bacteria cultures. That is unfortunate because taking samples and incubating them to grow bacteria is great scientifically sound way to get guidance for this question.

I have tried this "on-farm" method. Honestly, it is very insensitive to small differences in bacteria counts. But, it goes like this:
1. Fill a bottle with fresh colostrum as per usual protocol for the dairy.
2. Take a good smell of it - what does the fresh colostrum like?
3. Next day, take the bottle out of the refrigerator, stir the contents, smell again. You are looking for an "off" odor that would indicate bacteria growth. If it still smells fresh, put it back on the shelf.
4. Next day, repeat the stir and smell routine. Many dairies will find the colostrum has spoiled by the second day.
5. Next day if still okay, repeat the stir and smell routine. Only a few dairies will pass this test by the third day.
6. Repeat until it spoils.

A couple of resources to check if it smells bad by the second day: