Monday, January 30, 2017

How do Calf Caregivers Spread Diseases?

It seems like a contradiction to suggest that calf caregivers spread diseases. Nevertheless, research has conclusively shown that caregivers often are the culprits when calves get sick.

Let's look at three examples how this takes place.

Calves are housed in individual hutches outdoors where they are fed six quarts of pasteurized milk daily from 3-Qt. bottles. At feeding time a wagon full of these bottles is towed between the rows of hutches. Two workers scoop up arm loads of four three-quart bottles and go from hutch to hutch dropping a bottle in each bottle holder. I noticed that one worker managed to carry an extra bottle by holding the last two by the nipples. As the routine proceeded I also observed that not every bottle settled evenly into the bottle holders - some adjustment was required [note: this is where the worker's gloved hands came in contact with the contaminated bottle holder]. Then the same worker went back to the wagon, picked up three bottles tucking them  under her arm and grabbed two more bottles by their nipples [note: point of contact between contaminated glove and nipples].

Calves are housed in individual pens in a calf barn where they are fed six quarts of pasteurized milk daily from pails. These same pails are used to feed water. The feeding routine is to first go along each row dumping any left over water from the liquid feeding pail into a waste container. Then, milk is fed to individual calves.
You noticed, right? That is correct, as the water is dumped the worker's gloved hand touched one liquid feeding pail after another - very effectively passing pathogens along the row of pails. A few Strep. species bacteria probably don't make any significant difference. However, passing along Cryptosporidia parasites and highly contagious Salmonella bacteria should be avoided. 

Calves are housed in individual pens in a calf barn where they are fed three quarts of pasteurize milk three times daily from liquid feeding pails that are also  used to feed water. As I observe calf care after feeding I noted that several sick calves needed to be treated. The calf care person stepped into the first pen, gave the treatment to the sick calf, left this pen and promptly opened and stepped into the pen of the next calf to be treated. Boots, Boots, Boots. Feces on boots are a very effective way to carry pathogens from one pen to another.


Another of my clients has a little low tow-along cart. The cart has a place for extra disinfectant solution and a brush. A low plastic container allows the caregiver to step in and brush her boots. The solution is dumped out between calves. The routine is step in before entering the pen, step into the container upon leaving the pen, brush to remove an manure, dump the disinfectant solution, go on to the next calf. 

I saw a similar set up for a dairy using outdoor hutches. They carried the container in the back of a 4-wheeler, set it out on the ground, sprayed disinfectant on their boots while standing in the container, stepped into the wire pen, treated the calf, stepped out into the container brushing their boots off while being sprayed with disinfectant, changed gloves and on to the next calf. 

Note: Footbaths are particularly ineffective for controlling pathogen movement. In "Best Management Practices" above both calf enterprises dumped the foot bath between  uses. Research has demonstrated that even well-maintained footbaths often fail to control the spread of pathogens, especially Salmonella. 

Reference: Gardner, C.E. and Others, "Case Report: Management of an Outbreak of Salmonellosis on a Commercial Calf Raising Unit." The Bovine Practitioner, vol. 38, no. 2, pp147-154.

Saturday, January 28, 2017

Stopping Salmonella from Infecting the Next Calf

We frequently find that there are reservoirs of the Salmonella pathogen on dairy farms.  As long as immunity is high the animals do not show symptoms of being clinically ill (Salmonellosis).

With the changes that accompany the introduction of the Veterinary Feed Directive (VFD) we have some dairies that have stopped continuous feeding of antibiotics to young calves (usually less than 4 weeks but maybe as long as 8 weeks). 

On one  hand, for dairies where pathogen exposure is well controlled (for example, low bacteria counts in colostrum, calves moved from calving pens promptly and reliably after birth, feeding equipment effectively cleaned) taking away this "band-aid" has little effect.

On the other hand, if the farm's management practices have be skating at the very edge of containing clinical infections taking away the continuous feeding of antibiotics in the milk for preweaned calved may be all that is needed for subclinical infections to become clinical. 

Also, if there is significant exposure to Salmonella bacteria routinely in the calving pens and calf housing any event that causes even a little weakness in immunity among either cows at calving or young calves may be all that sets off a Salmonella event among calves. So, beyond treating sick calves, what to do when one or more calves are diagnosed with Salmonellosis?

Stopping Salmonlla from Infecting the Next Calf

1. Review colostrum management
  • Using blood from 10-12 calves (draw between 2 and 7 days of age) assess the effectiveness of creating passive transfer of immunity among calves. Click HERE for a guide to measuring passive transfer of immunity. When using blood serum total protein method, our goal is to have 90% at 5.0 and greater, 80% at 5.5 and greater.
  • Using 5 or more colostrum samples (collected from nipple or tube feeder just before feeding the calf) have laboratory cultures run to assess the level of bacteria in "as-fed" colostrum. Click HERE for a guide on sample collection. Our goal is to have less than 5,000cfu coliforms and less than 50,000cfu total plate count. 
2. Review calving pen management
  • Set the goal of having dry clean  bedding for all calves
  • Set a goal for promptly removing calves from the calving pen(s) to a clean, dry environment.
  • For any high risk dam suspected of being a Salmonella carrier, isolate her, remove the calf immediately after calving and do not feed her colostrum to any calf. 
3. Sanitize, sanitize, sanitize
  • Review washing procedures for calving equipment, colostrum handling equipment and calf feeding equipment. Click HERE for an equipment washing checklist.
  • Review ways in which caregivers may be spreading Salmonella from place to place and from calf to calf. 

[Veterinary Feed Directive (VFD) is a US based government program designed to place all feed-related antibiotic use under the direct supervision of the farm's veterinarian. A directive containing a description of the animals, the antibiotic to be used and the dose and duration of use must be written before the farm can purchase the product from a supplier.]

Thursday, January 26, 2017

Diagnosis: Salmonella Dublin
Now What?

This dairy has a number of group pens, calves are fed milk replacer with automatic computer controlled feeders. Recently they began having calves in the 7 to 10 day range show signs of diarrhea as well as elevated respiration rates and snotty noses.

Subsequent laboratory testing using tissue samples from a calf that died confirmed the presence of Salmonella dublin. The dairy and their veterinarian are working on a treatment protocol for the sick calves.

This case got me started on reviewing my file on this pathogen. I came across a short article written by Dr. Sheila McGuirk (retired from University of Wisconsin School of Veterinary Medicine) as a response to a reader question for Hoard's Dairyman.

I quote part of Dr. McGuirk's response below. It suggests how hard it is to control the spread of Salmonella dublin once it is present on a dairy. 

"S. dublin is unique amongst the other Salmonella bacteria in that it can infect cattle and establish a carrier state in some animals for life. Carrier cattle may not reveal themselves as being sick, but they shed infectious organisms in the environment and, very impactful for calf health, in colostrum and milk.

Along with feces, other bodily secretions of carrier animals discharge infectious organisms, making it very difficult to avoid the exposure of young calves to infection. Oral exposure to Salmonella organisms is common, but for calves that spend more than just a few minutes in a calving area, their skin, naval and feet can be a vehicle for bringing the organism to calf housing."  [emphasis added]

Hoard's Dairyman, September 25, 2014

So, now this dairy not only  has the issue of how to treat the calves that are already sick, there is the matter of establishing barriers to reduce the numbers of the organism being brought into the calf barn.

Wednesday, January 18, 2017

Winter Weather, Pneumonia in Calves?

In a brief article Dr. Russ Daly, extension veterinarian at South Dakota University, addresses:

  • Why cold winter weather increases the risk of young calves having respiratory infections.
  • Detection and prevention of pneumonia.
  • Antibiotic treatments.
  • Supportive care.
Click HERE to go to this article.

He includes two links to additional pneumonia-related articles,
  • Minimizing Respiratory Disease in Young Dairy Calves in Calf Barns
  • Dealing with Respiratory Disease in Young Dairy Calves. 
Enjoy. Keep warm and dry. 

Monday, January 16, 2017

Milk Yield per Milking for
Milkings 1-8 Post Calving

How much colostrum and transition milk should we expect from our cows? Another study measured these yields from 37 cows. The data are below as average yield.

   Milking No.        Kg          Lbs.   
1 7.5 16.5
2 4.9 10.7
3 7.2 15.9
4 11.4 25.1
5 10.7 23.5
6 13.1 28.9
7 11.1 24.3
8 14.2 31.2

The study colostrum feeding program for calves fed 10% of birth weight (40kg) required 6L or Kg per calf. Thus, on the average these yields (7.5 quarts) were enough to meet program needs where they fed calves colostrum from their own dams.

If the dairy chooses to feed 2nd, 3rd and 4th milkings (transition milk) to calves, on the average these dams produced nearly 52 pounds (23.5kg) over 36 hours. When I collected transition milk for my calves I found that I had enough volume to feed it exclusively to all my heifer calves for the first seven to ten days (I fed 4 quarts daily for most of the year and 5 quarts during January, February and March).

Reference: Dunn, A, and Others, "Effect of concentrate supplementation during the dry period on colostrum quality and effect of colostrum feeding regimen on passive transfer of immunity, calf health and performance." Journal of Dairy Science 100:357-370. Research was done in Ireland during the months of February, March and April, 2014.

Monday, January 9, 2017

Miner Institute Farm Report

If you are not already receiving this monthly Farm Report from the Miner Institute now is the time to sign up for it. Just send an e-mail to Rachael Dutil at this address so she can add your name to the mailing list to receive a note each time a new issue is published. 

To see the current issue do this:

The URL is or click HERE to go there. 

Click on the drop-down item "Dairy" and then click on "Farm Report"

The January issue topics are:
  • Rethinking Fiber Dynamics and Grass Forages
  • Calving: To Assist or Not to Assist
  • A New Year's Resolution
  • Corn Hybrid Silage Trial Results
  • Use of Bulk Tank Milk Fatty Acid Data to Make Nutrition & Management Decisions
  • Blurring the Lines: Dairy Beef
  • Resolutions with Real Impact
  • Edge-of-Field Phosphorus Losses
  • What's Happening on the Farm
  • Soybeans in the North Country: An Update

Friday, January 6, 2017

Yet More Evidence that Feeding More High Quality Colostrum Has Benefits for Calves

In an Irish study 37 calves averaging 40.4kg (90.5 lbs.) were allocated to two colostrum feeding treatments:
  • 5% of body weight of colostrum (55g/L IgG) fed (2L or 2.1 qts) within 1 hour after birth followed by the same volume of second milking (est. 30g/L IgG) at 12 hours.
  • 10% of body weight of colostrum (55g/L IgG)  fed (4L or 4.2 qts) within 1 hour after birth followd by 2L (2.1qts) of similar quality colostrum at 12 hours.
These feedings translate into:
  • 5%-calves = 110g IgG first feeding, 60g IgG second feeding = total 170g
  • 10%-calves = 220g IgG first feedng, 110g IgG second feeding = total 330g
What happens in the calves? When we compare circulating antibodies in their blood, the 10% calves had 48% more antibodies than 5% calves at 24 hours and 50% more antibodies than 5% calves at 48 hours. 

What happens later? When we compare diarrhea treatment rates, the 10% calves had a 43% treatment rate compared to 53% for 5% calves. Note that these were group housed with an automatic milk replacer feeder and the program had a low threshold for starting treatment.

For comparison, one of my Calf Wellness dairy clients feeds 4qts within one hour of birth, another 2 quarts at 6 hours and another 2 quarts at 12 hours. [All first-milking colostrum tested at greater than 50g/L.] Using blood serum total proteins as an estimate of immunity their results look like this:

Blood Serum Total Protein Values
Visit Date                                                       Dec16  Nov16 Oct16  Sep16  Jun16 Mar16
Number of reported values                             85        45        45        168      78        35       
Number of values at 4.5 or below                   0          0          0          2          0          0         
Number of values at 5.0 or below                   0          1          1          12        6          2         
Percent values 5.5 and greater                        91%     91%     98%     85%    92%     92%    
Average                                                           6.3       6.4       6.1       6.4       6.2       6.2      
Median                                                            6.2       6.4       6.0       6.4       6.1       6.1  

Bottom line is that feeding more IgG's results in more antibodies in the blood, period.  


Thursday, January 5, 2017

What Level of Bacterial Contamination is "Normal" for Colostrum?

The January issue focus is on bacterial contamination in colostrum. 

The key points are:
  • ·         Why do we care about bacterial contamination of colostrum?
  • ·         So, what are realistic, cost-effective goals for bacterial contamination levels?
  • ·         Are dairies feeding low bacteria count colostrum (less than 100,000cfu/ml)?
  • ·         Should we accept failure as “Normal?”
  • ·         How to make “Success” the new normal on a dairy.
       To access this issue click HERE or paste this URL in your browser


Tuesday, January 3, 2017

More on Bacteria Counts in Colostrum

In my December 29, 2016 post I suggested that bacteria counts over 200,000 or 300,000 should not be considered "normal" for a commercial dairy.

I went back in my files to check on a 400 cow dairy in western New York State. We started working together in the fall of 2003 to improve colostrum management.

These are the culture results from the following February and June, 2004.
Table 1. Lab results reported on 6/17/04
Sample ID
Coliform bacteria (cfu/ml)
Total bacteria (cfu/ml)
Colostrum #1113 Kevin 3/3/04
15,600 (Strep. Species)
Colostrum #1317 4/17/04
Colostrum #1285 M 4/18/04
7,800 (Staph. Species)
Colostrum #1306 M 4/29.04
TNTC (Strep. Species)
Colostrum #1135 R 5/4/04
Colostrum #10 B 5/23/04

Table 2. Samples reported February, 2004
Sample ID
Coliform bacteria (cfu/ml)
Total bacteria (cfu/ml)
Colostrum #494 M 1//26
TNTC (Staph)
Colostrum #1033 T 1/30
Colostrum #1126 T 2/5
19,800 (some yeast)
Colostrum #701 frozen
Waste Milk
Colostrum #1167 M 2/5

The two cows with high bacteria counts were chronic mastitis animals that appear not to have cleared these infections during the dry periods. 

When they submitted samples  three years later in May 2007 the culture results look like this:
Sample ID
Coliform bacteria (cfu/ml)
Total bacteria (cfu/ml)
Colostrum #661 M
Colostrum #1293 B 4/14
400 (300 Staph species, 100 Strep species)
Colostrum #1546 M 4/11
1,000 (800 Staph species, 200 Strep species)
Colostrum #1555 D 2/15
Colostrum #1694 B 4/26
400 (200 Staph species, 200 Strep species)
Colostrum #1729 D 4/19
10,500 (10,200 Staph species, 300 Strep species)

When they submitted samples in March 2012 the culture results look like this:
Sample ID
Coliform bacteria (cfu/ml)
Total bacteria (cfu/ml)
#2269 N 1-26
900 (700 Staph species, 200 Strep species,)
#2112 M 1/25
900 (600 Staph species, 200 Strep species, 100 gram pos bacillus)
#2433 M 2/3
600 (200 Staph species, 100 Strep species, 300 gram pos bacillus)
#2217 B 1/28
3,000 (2,000 Staph species, 500 Strep species, 500 gram pos bacillus)
#1881 M 2/14
4,500 (3,000 Staph species, 1,000 Strep species, 500 gram pos bacillus)
#2452 N 2/22
500 (200 Staph species, 300 Strep species)
#2109 N 2/21
1,300 (800 Staph species, 400 Strep species, 100 coliforms)
#2449 B 2/5
1,200 (700 Staph species, 300 Strep species, 200 gram pos bacillus)
Can they sustain this level of colostrum management? Here are the Spring, 2016 culture results.

Sample ID
Coliform bacteria (cfu/ml)
Total bacteria (cfu/ml)
32,500 (25,000 Strep species, 7,500 coliforms)
2,300 (1,500 Strep species, 500 Staph species, 300 gram pos bacillus)
1,600 (800 Staph species,. 300 Strep species, 500 gram pos bacillus)
300 Strep species
300 (200 Strep species, 100 gram pos bacillus)
1,300 (1,000 Staph species, 200 Strep species, 100 gram pos bacillus)
4,400 (1,300 Staph species, 2,500 Strep species, 600 gram pos bacillus)
I conclude that low bacteria counts can be achieved - over 12  years on this dairy. Here and there a blip but overall results are good. 

What does it take to get here? Good protocols and strong "buy-in" by both the dairy owner and the herdsman. 

Do you have a good example to share? Let me know at