Tuesday, November 29, 2016

November Calf Management Newsletter
"Preventing Scours and Pneumonia vs. Treating Sick Calves"

The November issue is now posted at www.atticacows.com, click on "Resources" and then "Calf Management Newsletter."

The key points:
  • Long-term consequences of calfhood scours and pneumonia.
  • Shifting emphasis to "calf wellness" rather than treating "scours" and "pneumonia."
  • How to start a "calf wellness" program.

Monday, November 28, 2016

Impact of Being Sick as a Calf on Later Growth and Milk Production

I am preparing a statement on the consequences of calfhood sicknesses on growth and milk production. Below is a paragraph summarizing the findings of a recent presentation.

In a summary of research using two large dairy farms Dr. Mike Overton gave us a listing of the impact of  infections resulting in scours and/or pneumonia during the first 70 days of life. These are listed:
  • Weight at 90 days of age: scours calves weighed 3.1 lbs. less than healthy calves
  • Weight at 90 days of age: pneumonia calves weighted 12.7 lbs. less than healthy calves
  • Likeihood of being culled before first calving: pneumonia calves were 2.8 times as likely to be culled compared to healthy calves. No difference for scours calves.
  • Likeihood of being culled after calving and before 150 days in milk: pneumonia calves were 1.4 times as likely to be culled compared to healthy calves. No difference for scours calves.
  • Milk (305 day estimated ME): 649 pounds less milk for pneumonia calves compared to healthy calves.

Bottom line is that both scours and pneumonia depress the growth and later production of the animals both as heifers and later as milking cows. These are some handy numbers. 

Reference: Overton, Mike “”Importance of Producing a Quality Dairy Replacement Heifer.” Proceeding of the Dairy Calf and Heifer Association, 2016, pp 55-59.

Monday, November 14, 2016

Four Heifer Calves, One Dam

I ran across this picture - four heifer calves pictured with their dam. Just paste the URL in your browser window.

4 DAIRY CALVES ~ One California dairy cow beat out some major odds when 
she gave birth. The cow produced four healthy, female calves in one 
litter. The chance of that occurring are one in 179 million.

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 [smleadley@yahoo.com].

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 https://www.farminguk.com/News/Disinfection-and-hot-washing-crucial-to-prevent-crypo-spread-from-calf-jackets_44437.html ).

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.