Monday, October 24, 2016

How Does Your Colostrum Compare?

Another national study of colostrum is reported in the November issue of the Journal of Dairy Science. These 24 dairies were in northern Victoria state in Australia.

Antibody concentration:
Australian dairies reported a Brix average of 21%. This compares to the US study average of 21%.
Are you testing colostrum with a Brix refractometer? If "Yes," what is your average reading?

Total bacteria count:
Australian dairies reported bacteria counts (Total Plate Count, cfu/ml) as 42 percent over 100,000cfu/ml. This compares to the US study with a values of 45 percent. 
Do you sample and culture your colostrum at least once a year? If "Yes," what percent of your samples were less than 100,000cfu/ml total plate count goal?

Coliform count:
Australian dairies reported bacteria counts (Total Coliform Count, cfu/ml) as 6 percent greater than 10,000cfu/ml. No comparable data are available for US.
Do you sample and culture your colostrum at least once a year? If "Yes," what percent of your samples were leass than 10,000cfu/ml coliform count?

If you combine all three criteria (antibody concentration, bacteria total plate count, bacteria coliform count) the percent of samples that met all three acceptable thresholds was 23 percent for Australian samples. The comparable figure for US study was 39 percent. 

The message is that the chances of feeding colostrum that is either too low in antibodies or too high in bacteria can get pretty high on a dairy farm. Only good management practices, including testing, can prevent this from happening. 

Reference: A.J. Phillips and Others, "Survey of bovine colostrum quality and hygiene on northern Victoria dairy farms." Journal of Dairy Science 99:8981-8990 Nov 2016

Friday, October 21, 2016

Johne's Dam and Her Calf

I was asked about Johne's control on a dairy and managing the calving process to reduce risk of transmission.

In my opinion, the risk of transmitting Johne's [mycobacterum avium ss. paratuberculosis] to calves can be reduced by following three straightforward steps:

1. For the calf born to a known Johne's dam, do not feed this dam's colostrum to any calf. 

2. For the calf born to a known Johne's dam, take the calf away from the dam as soon as practical -  always before the calf stands. Remember that mother (hair coat, licking the calf, fecal contamination of calf surroundings) is a pathogen factory.

3. For all calves, if possible calve known Johne's dams in a place separate from where other calves are being born - isolate the feces from known dams as much as possible from all newborn calves.

Thursday, October 20, 2016

Somatic Cell Counts and Feeding Waste Milk

I was asked today if I knew of an upper limit for somatic cell counts (SCC) in pasteurized waste milk (nonsaleable milk) being fed to calves. If the SCC is over 500,000 or 1,000,000 should it still be fed to calves?

First, how do we expect the nonsaleable milk to be any different that the  milk we are selling? That means we have to think about where this milk comes from. The reason we are not selling the milk is frequently the presence of antibiotic residues. While some cows are being treated for a uterine or respiratory infection others have received treatment for mastitis. 

So, it is logical that this nonsaleable milk partly from mastitis cows could be higher in SCC than the milk being sold. In addition some farms supplement their volume of sick cow milk for calves with that from one or more of the highest SCC cows in the herd - this keeps the SCC in the saleable milk tank lower and effectively increases the calf milk supply.

Second, do we have published research showing that the SCC in pasteurized nonsaleable milk has negative consequences for calves? That is, do calves avoid drinking it? Or, does high SCC milk cause digestive upsets or lower rates of growth? I have no knowledge of any such research.

Third, is high SCC milk different from low SCC milk in some other ways? We do know there is a tendency for high SCC milk to be lower in total solids and protein than low SCC milk. 

So, are there guidelines for SCC in milk fed to calves? 
1. I do not think so at least based on published research. If any reader knows about such research do me a favor and send me an e-mail with the reference [].

2. If SCC is at 1,000,000 or higher it probably is a best management practice to check the milk solids level with a refractometer before feeding this milk to calves. We might need to supplement our milk with milk powder of our choice to bring it up to our desired level (e.g., 12%, 15% solids). 

Tuesday, October 18, 2016

Calf Coat Care: Let's not pass on cryptosporidia from one calf to another

At a recent event Andy Dodd, AHDB technical manager (UK) had a few words to say about calf coat care ( see ).

His point was that improperly cleaned calf coats can easily pass the eggs of this nasty parasite from one calf to another. 

The essentials for getting rid of the parasite eggs? If possible wash at a temperature at 60C (140F). That cooks the eggs.

I observe that if washing at that temperature is not possible, then set the dryer on the "HOT" setting and cook the eggs that way. But, remember the critical temperature is 140F or 60C.

Disinfectants? The only one that I know about that will kill these persistent parasite oocysts is chlorine dioxide solution. See HERE for more information about this disinfectant.

The point of Andy's presentation is valid no matter how you clean calf coats - do a good enough job so we are not passing parasite oocysts from one calf to the next.

Friday, October 14, 2016

Estimating  Calf Weights

We all have looked at a calf and mentally estimated about how much she weighs. The true of the matter is that studies have confirmed that people are abysmal at estimating weights.

So, yesterday I am on a dairy. The calf manager pulls a dairy weight tape out of his pocket as says, "Take a minute and show me the right way to use this."

I took the rolled up tape, shook it out and after cornering a calf slipped the tape around her body just behind the front legs - technically the heart girth position.

I showed him how to pull the tape "just right." Tight enough to flatten the hair coat but not enough to begin to stretch the tape.  

After I took a reading he tried it and came up with almost the identical number. Good. Lesson learned. 

HOWEVER, I asking him, "Where is your Holstein calf weight tape?"

"Huh?" he said.

Then I explained that the mature animal weight tape was developed to be most accurate at  breeding size for Holstein heifers. It is pretty sloppy when we get under 440 pounds (200kg). That was the reason that the Penn State research team developed a tape that was specifically for calves (under 220 lbs, 100kg).

So, I mailed two Holstein calf weight tapes to the farm today and now they can get more reliable weights for the calves as they leave the hutches. 

I f you Google "Holstein calf weight tape" you will get a series of places to buy one as well as some background links to how the tape was developed. 


Monday, October 10, 2016

Stress for Calves

In a short article published in the October issue of the Bovine Veterinarian magazine the author, Dave McClellan, talked about respiratory illness in young cattle. Quoting a study for which I do not have the full reference (Bagley & Griffin, et al.) they were summarizing causes of respiratory illness:
1. Stress
2. Viral
3. Bacterial

Then under stress the authors listed these - this is a nice summary of stress, it got me thinking

Irritant gases
Nutritional deficiencies

Now, isn't that a nice checklist if you want to see  how you are doing to limit stress for your young dairy animals?

Friday, October 7, 2016

Feeding the "Left-Over" Milk

Not every batch of milk is just exactly the correct volume to feed the calves this feeding. Usually we try to have just a small amount of milk left over. That can be dumped when we are getting ready to wash our transport tank.

But, sometimes the volume is clearly going to be more than we feel comfortable dumping. We know how to fix this problem. Just feed extra to the oldest calves - feed six or seven quarts rather than the prescribed four quarts.

Now, here is the question. Is this a best management practice?

Answer? NO.

What's the problem with feeding out the excess milk to the oldest calves?

1. If these calves are being weaned the extra milk is going to provide a slug of extra energy. This energy acts to suppress calf starter grain intake. This is just the opposite of what we are trying to accomplish - that is, getting these heifers to eat MORE grain so they are "rumen ready" for the transition pens.

2. If these are the calves just before we are starting to the weaning process the extra milk is going to provide a big slug of extra energy. This energy further delays these calves coming up on their consumption of calf starter grain. Again, this is not what we are trying to do with five to seven week old calves - they should be on a plateau or level feeding milk feeding program.

With my intensive-fed calves as they got past about three weeks their grain intake began to pick up slowly from day-to-day. I held their milk intake even from two to six weeks of age. Then, since I monitored grain intakes, as soon as their grain intake was consistent and at least one pound a day I began to taper down the milk. Imagine how I could have messed up this process if I just "dumped" extra milk on these calves.

I had a lot of open pasture land near my barns so extra milk fertilized the pasture before I went into the barn to clean up. As long as I spread the milk around the plants seemed to do just fine. It is, however, a great way to kill thistles and burdock plants.

Tuesday, October 4, 2016

What is an Intensive Milk Feeding Program?

The one simple definition of an intensive milk feeding program for preweaned dairy calves is probably not possible.

What is the baseline or standard milk feeding program? Thirty  years ago it was two quarts of either milk or milk replacer fed twice daily. That usually delivered 1# of milk replacer powder daily. Twenty years ago it was the same. I am not sure but it may be the same on some dairies in 2016.

Let's compare this to three feeding programs reported in a recently published research project.

Recently published research (Hill and others, 2016) fed three intensive-feeding preweaned rations:
(weights are as-fed milk replacer powder, 28-20 and it was reconstituted at 14% solids)
  • Lowest    = 1.45#(0,66kg) for 39 days, 0.7#(0.33kg) for 3 days (2x feeding at 6:30AM and 2:00PM)
  • Middle    = 1.9#(0.88kg) for 5 days, 2.4#(1.1kg) for 23 days, 1.45#(0.66kg) for 18 days, 0.7#(0.33kg) for 7 days
  • Highest   = 1.9#(0.88kg) for 5 days, 2.4#(1.1kg) for 37 days, 1.2#(0.56kg) for 7 days

The lowest ration is 45% higher than the "standard" or baseline ration. Thus, this might be called an "intensive" feeding program.

Note that the "middle" ration feeds at a much higher rate for four weeks and then starts stepping down until it levels out at 0.7# per day.

One of the consequences of higher milk/milk replacer feeding rates is a delay in consuming calf starter grain. My experience over several years was as I edged up in my milk replacer feeding rates I added days to when calves started regularly eating grain. 

I followed the "middle" ration program for several years. I dropped from 2# to 1# powder fed daily as soon as calves were regularly eating about 1/2 quart or 1/2 # of grain daily for several days in a row. Most of my calves compensated easily by eating a greater amount of grain. They were eating around 5 # of grain daily before they went off milk entirely one to two weeks later.

However, it was significant that not all calves behave the same way. If I recall correctly about 20 percent of the calves needed a few extra days before their initial grain intake came up to the minimum of one-half quart a day. I had to put a tag on their hutches so we would remember to continue the regular milk feeding. I think being flexible on the weaning program helped me have healthier calves in the transition pens.