Wednesday, April 29, 2015

Klebsiella spp. Bacteria in Colostrum

Last week we collected ten "as-fed" samples of colostrum on a large dairy. We cultured these colostrum samples on blood agar plates for 48 hours. 

Results? All ten samples contained colonies of Klebsiella bacteria. The lowest colony forming units/ml (cfu/ml) number was 600 cfu/ml and the highest was 7,500 cfu/ml. The farm's upper threshold for Klebsiella bacteria in colostrum is 5,000 cfu/ml. Everyone is unhappy about these results. 

The question of the day: "How is the colostrum being inoculated with this environmental bacteria?"

On a farm visit just one week before we checked both the bottles used to store the colostrum and the esophageal tube feeder used to deliver the colostrum. We used a SystemSURE Plus luminometer that reports back in relative light units (RLU). These RLU's are highly correlated with standard plate counts from bacteria cultures.

The food industry standard upper threshold for RLU's for clean food processing equipment is 10. Our tests for a storage bottle was 0. For the tube feeder the RLU was 1. So,we feel these are an unlikely source of the Klebsiella bacteria. 

That leaves teat preparation failure and the sanitation of the milking equipment as inoculation sources. This week we are planning on checking teat preparation. We have a supply of alcohol pads to wipe the "clean" teat ends before the milking unit is attached.

Also, we have put in place a "pre-milking" sanitizing rinse for the milking unit. [It may be helpful to know that the fresh cows are milked in the calving pen shortly after calving. One milking unit is used to collect all the colostrum.] Our plan is to make a two-gallon chlorine solution (500ppm chlorine) and pull it into the milking bucket through the claw just before collecting colostrum.

After a week to get the new protocols in place we will collect another set of "as-fed" samples and see if we have been successful in shutting down the Klebsiella inoculation of the colostrum.

Friday, April 24, 2015

Challenges of Warming Colostrum

Yesterday I was on a dairy that feeds colostrum from bottles stored in a refrigerator. They have to warm each bottle before it can be fed. 

As I stood at the sink in the milk house I asked the calf care person to show me how she warms colostrum. She sat a plastic container in the sink and filled it with water.

The critical piece of information here is the temperature of water in the container. She put adjusted the hot and cold water faucets to a familiar position and put her hand into the water. After a moment she turned up the hot water volume a bit. Then she said, "There, that is just right."

The water was actually close to 130 F (55C). She was correct - this is a very good temperature for warming colostrum without damaging the antibodies. You may recall that when colostrum is exposed to excessively high  temperatures (more than 140F, 60C) the antibodies are damaged and are no longer effective for preventing infections. 

I asked her, "How do the guys on the night shift warm colostrum?" The reason I asked this question is that I had just asked her about the source of the hot water in the milk house. She said it came from the same supply as the hot water for washing the milk pipeline in the milking parlor - that water is 170F (77C). 

She told me that her instructions to the night workers that warm colostrum feeding newborn calves is to run the water no hotter than they can stand to run over their hand. She was quite confident that these workers were following the warming protocol satisfactorily. 

On another farm I saw a short (8 inches or 20cm) piece of milker hose on the end of the mixer faucet in the milk house sink. The dairyman had inserted at a 30 degree angle an inexpensive rapid-read thermometer into the hose. This instrument measured the temperature of the water going through the milker hose - thus, when you wanted 130F water for warming colostrum you simply adjusted the hot and cold water faucets until the thermometer was as this temperature.

Just for review you  may want to go over the points on this Colostrum Feeding Checklist. Click HERE for this checklist.   

Thursday, April 23, 2015

How to Make a Bad Situation Worse:
Dirty Calf Pails After Washing!

During a recent farm visit I took the opportunity to check out the pails they have washed. All the 10-quart plastic pails (buckets) are washed before going to the hutch for a newborn calf. 

I have recently been using the Hygiena SystemSure Plus unit to do ATP monitoring. The ATP test is a process of rapidly measuring actively growing microorganisms through the detection of adenosine triphosphate. An ATP monitoring system can detect the amount of organic matter that remains after cleaning a surface (for example, calf feeding equipment). 

Thresholds used in the food processing industry are less than10 RLU for direct food contact surfaces and less than 50 RLU for environmental surfaces. For reference, on this same farm the inside surface of a grain feeding pail for a 3 week-old calf tested at 354 RLU; same pail 8 week-old calf = 366 RLU.

Now, back to the "clean" pails.

We tested the top pail in a stack of 15 "clean" pails. It was dry. The RLU value was 2925. Lots of remaining organic matter post-washing. 

We tested the bottom pail in the same stack of "clean" pails. RLU value was 5776. Ah. Stacking pails after washing appears to be an effective way to increase bacteria presence.

Thus, not only does the dairy need to do a better job of cleaning their pails but also needs to work out some way to set the pails upside down separately so they can drain and dry.

The recommended protocol for washing is found HERE.

Monday, April 20, 2015

Starter Grain Intake by Age
for Milk-Fed Calves

As part of a research trial the starter grain consumption was measured daily. (Laberge, R.J. "Early starter intake by nursery calves: the impact on growth, health and gastrointestinal development" Minnesota Nutrition Conference, pp 134-135, 2013).

Calves had ad lib water and starter grain. They were fed 22:20 milk replacer at the rate of 1.5% of birth weight (for example, 90 pound birth weight = 22 ounces (612g) milk replacer) mixed at 12.5% solids until 42 days of age. Then for days 43-49 they receive one feeding daily. No forage was fed. 

The average age at which the calves reached selected intakes of starter grain were:

    Starter Grain               Age
    Intake level                (days)
(Grams)   (Pounds)
   250          .55                19
   500         1.1                 24
 1,000        2.2                 31
 2,000        4.4                 44

On the basis of slaughter data of these 18 calves the authors hypothesized that gastrointestinal health could have been improved by the addition of small amounts of forage to the ration after a benchmark level of starter grain had been reached. For example, after 1,000 g/day level was reached add 20-40 grams of hay (0.1 lbs.).

Based on my on-farm observations with many dairies there is a significant problem using level of grain intake to begin adding forage to the ration. Most calf rearing enterprises that house calves individually do not measure or estimate in any way daily starter grain intakes. The grain pails are just kept between 1/4 and 3/4 full without any significant effort to track consumption rates.

Wednesday, April 15, 2015

As Straw Intakes Goes up, Gains Go Down
Among 8 Week-Old Hiefers

In a research trial (Hill, T. M. and Others, "Roughage amount, source, and processing for diets fed to weaned dairy calves." The Professional Animal Scientist 26:181-187 2010) that ran for 56 days weaned Holstein calves from a single dairy were fed a 21% c.p. textured grower feed and 0, 3, 6, or 9% chopped wheat straw blended in by hand at the time of feeding. 

The average daily gains 8 to 16 week-old heifers over the 56-day trial by straw feeding rate were:

Chopped straw %            Ave.Daily Gain
                                     (Pounds) (Kilograms)
     0                                  2.8         1.27
     3                                  2.4         1.10
     6                                  2.1         0.96
     9                                  2.0         0.89

Other growth measures were Hip Width, Body Score; they also declined as straw intake increased.

In contrast, when grass and alfalfa hay were fed at low levels (3%) average daily gains increased. 

As feeding rates of these forages continued to increase beyond 3 percent, however, rates of gain tapered off.          

Monday, April 13, 2015

Checking Colostrum Quality
On-Farm Tools

Have you used a Colostrometer or Brix refractometer?

They are on-farm tools for assessing the antibody concentration in bovine colostrum. Neither of them directly measure antibodies. Rather, they use highly correlated indexes to make rough estimates of actual antibody concentrations.

In a recently published article (Bartier, A. L. and Others, "Evaluation of on-farm tools for colostrum quality measurement" Journal of Dairy Science 98:1878-1884 April 2015), the authors reported that both of these instruments were effective for identifying poor quality colostrum. 

That is, they worked quite reliably to exclude low concentration colostrum from first feeding for newborn calves. 

As an aside, this study again reported just under thirty percent of the samples measuring as "poor" quality - less than 50g antibodies per liter (that is the internationally recognized lower threshold for colostrum acceptable for first feeding for heifer dairy calves). 

By lactation the average immunoglobulin type G (IgG) concentrations were:

First lactation         62g/l
Second lactation    60g/l
Third+ lactation    70g/l  

These averages emphasize for me that we should be checking colostrum from first lactation dams - a lot of that colostrum is just as antibody rich as colostrum from older dams. 

Friday, April 10, 2015

Robotic Milking & Colostrum

I visited another dairy with robotic milking equipment. This dairy, like several others I have visited, does a great job managing the cows and producing lots of milk.

However, this dairy, like several others I have visited, manages to highly inoculate the colostrum by the time it goes into the nursing bottle for the calf. 

How can this happen? Well, let's start at the beginning. We want clean teats for colostrum collection. Is the robotic milker equipment set up to prepare fresh cow teats for milking? Not necessarily depending on the dry cow housing. In robotic barns I recommend restraining fresh cows post-calving and manually cleaning up the teats with special attention to teat ends - don't depend on the robot to do the full job on these cows. 

Next we need clean milking equipment. I have not seen any gaps in sanitation in the robotic units during my visits. I cannot make any recommendations for improvement at this step.

What comes next? Well, it depends on the brand of robot. All of them send the colostrum to some kind of holding unit. Almost uniformly none of the ones I have seen receive special attention to prepare for colostrum collection. I recommend cleaning using a simple four-step washing procedure. Click on this link, Washing Protocol, to access the procedure.

If the storage unit is judged to be clean, nevertheless, I recommend a quick rinse pre-collection with a hot water bleach solution. This is the same recommendation as I make for any colostrum handling system.

Where there may be some delay in feeding and/or processing the colostrum I suggest adding a food preservative such as potassium sorbate to extend the generation time for bacterial growth. A brief summary of how much product to add to various quantities of colostrum can be found HERE. Other information on potassium sorbate use in colostrum is at www.calffacts.com.

A quick summary about using potassium sorbate in colostrum at the DairyHerd magazine archives can be found at this location - click HERE.

Tuesday, April 7, 2015

How are the heifers doing?

This is the universal question - I ask it every time I am on a farm or meet a client.

Hidden, however, in this question is another question. That one is, "How do I measure the development of my heifers?"

An associate recently shared an Excel spreadsheet he uses to summarize the information collected from the heifers on his clients dairies. 

As you already would guess the first five columns in the spreadsheet are these:

ID  BirthDate  MeasurementDate  Weight  Height

He and the dairyman agreed on the development goals - mature cow weight and height.

Then, the next two columns are what caught my attention. They are:

                                           MatureBodyWeight  MatureHeight
                                             (Percent)                    (Percent)

For a 2 month old                     11.0                          56.9
For a 5 month old                     25.7                          70.0
For a 12 month old                   55.7                          80.0

As I scanned the spreadsheet I picked up some contrasts that began to raise questions about the heifer enterprise. For example, let's compare two sets of heifers:

One heifer 1.7 months old       10.4                           56.9
One heifer 2.2 months old         8.3                           55.2

What is happening to have the second heifer 15 days older than the first weighing only 125 pounds  compared to her pen mate at 156 pounds?

or these two heifers:

One heifer 4.1 months old       25.0                           67.5
One heifer 5.6 months old       25.3                           71.7

What is happening to have the second heifer, 45 days older than the first, at the same weight?

The percent of goal achieved works quite well in capturing the variation in rate of development. You might want to try adding these columns to your growth spreadsheet.



Monday, April 6, 2015

Let's Raise Our Bull Calves

We have a good market, price is good, costs look reasonable, let's do it!

At the beginning the bull calves gained well and brought a good price.

Then, we noticed that our treatment rate for pneumonia in the calf/heifer barn seemed high. The treatment records showed that our impression was correct. Our vet commented on the ammonia odor in the barn when he was there checking out several calves with pneumonia.

Oh, by the way, did you remember that when you double the number of calves in the same space (sometimes called overcrowding) they produce twice as much feces and urine?

This automatic-feeder operation was working well before adding the bull calves. Calves step up to 12L a day and the ten days before weaning they start decreasing one liter daily until weaned. With heifers only there was about 30 square feet of resting space per calf. Pneumonia treatment rates were elevated a little -probably some improvement in ventilation would have been desirable even before the bull raising began.

Then, the number of calves doubled. Ammonia concentration went up. Overcrowding stress increased - space per calf went from about 30 square feet per animal down to barely 15 square feet. Whole-pen treatment for pneumonia began when fall weather arrived. 

Solution to the pneumonia problem?

1. Stop raising bull calves - cut pen population in half. 
2. Install positive pressure ventilation tubes to increase rates of air exchange.

Results?
Current pneumonia treatment rate is well under ten percent and no whole-pen treatment has been needed.

Thursday, April 2, 2015

Cooking Antibodies is So Easy

I asked the routine questions about colostrum management on a recent farm call. We got to the point where we were talking about using frozen colostrum.

The farm was carefully following best management practices in collecting and freezing colostrum. 

We then moved on to thawing and feeding this colostrum. We went through the thawing process step-by-step. 

1. Turn on hot water tap and let it run until hot (same water source as used to wash the parlor).
2. Place two nursing bottles of frozen colostrum into 5-gallon pail.
3. Fill with hot water up to top of bottles. 
4. Wait about ten minutes, dump out water and refill with hot water. 
5. Wait until the colostrum turns to slush, shake bottles, push rapid-read thermometer through vent hole in nipple in order to monitor colostrum temperature, dump out water and refill with hot water.
6. Check thermometer and feed when up to 102F. 

Should work okay. But, how hot is hot water? 

We turned on the hot water tap, let it run until it appeared hot, let it run into a nursing bottle to make it easy to measure the temperature with a rapid-read thermometer. Hmmmm - 160 - 165F.

Let's see - antibodies in colostrum get "cooked" (denatured to be very correct) at temperatures above 140F. 

Each time this dairy was refilled the 5-gallon pail with 160+F water the chances of the colostrum in contact with the bottle surfaces being overheated went up.

We did not come up with a modified procedure at that visit. However, everyone thawing colostrum seems to understand the need to not "cook" the antibodies in the colostrum.