Recent weather has resulted in ideal  conditions for the growth of bacteria associated with environmental mastitis.  The attached 2 page article gives some background concepts related to preventive strategies for reducing the risk of mastitis.  Here is a summary of the:

Take Home Message:

• Wet pastures & bedding in combination with summer temperatures will result in increased opportunities for cows to develop environmental mastitis
• Increased cases of clinical mastitis caused by Gram negative pathogens may be expected as a result
• Preventive strategies should include
  • Ensure that J5 vaccines are properly used and consider booster injections
  • Consider the use of barrier teat dips until bedding dries out
  • Remove wet bedding as frequently as possible
  • Continue to focus on implementing principles of Good Udder Preparation http://www.uwex.edu/milkquality/PDF/Vol_3_pdf/Pg_3_61-69_seven_habits.pdf

I have received several phone calls from both producers and veterinarians that are dealing  with herds that have experienced frozen or frostbit teats on dairy cows or dairy heifers.  The weather conditions that we have experienced have been ideal to create this situation and I wanted to alert everyone to the steps that can be taken to minimize this problem. 

Frozen or frostbit teats generally occur when wet teats are exposed to bitterly cold conditions.  Risk factors for developing this syndrome include:   outwintering of lactating cows, the failure to provide dry bedding sources or windbreaks and long walkways that cows with wet teats have to traverse after being milked.  Another high risk situation for heifers would be the presence of a "sucker" heifer within an outwintered group.

There can be some confusion regarding diagnosis of frostbite and the primary differential is usually Herpes Mammilitis.  A couple of key differentials is that some teats with herpes should demonstrate the distinct small vesicles and the skin often becomes thickened.  The attached Word document has a couple of photos that may be helpful in diagnosis.

There is no specific treatment for frostbite and the general recommendation is that supportive care (teat salves, the use of high emollient teat dips) is used.  If lactating cows develop frostbite, they are at extremely high risk for developing subclinical or clinical mastitis and it is not uncommon for the primary pathogen to be Staph aureus.  This pathogen often predominates because it is a common teat skin contaminant.  Farmers often discontinue teat dipping in periods of bitterly cold weather but that is often counterproductive and may result in outbreaks of contagious mastitis.  The key is to focus on prevention. 

Please feel free to contact me if you have herds that are dealing with this issue.

The Cowscope Newsletter is a monthly newsletter that is produced by Ken Bolton, Dairy and Livestock Agent at the UW-Extension, Jefferson County Office. This issues features articles on:

• A Management Approach for the Control fo Mastitis Infections in Dairy Cattle - Part 3
• What Does it Cost to Raise that Heifer
• Revised Udder Health Management (UHM) Reports - Part 2
• Bovine Somatotropin (BST) Safety Around the World
• Glycerin as a Potential Feed Ingredient for Dairy Cattle
  

For complete newsletter, please refer to the webpage at:

http://www.uwex.edu/ces/cty/jefferson/ag/Cowscope08.html

Dear All
This month AgSource Cooperative Services will be launching the new Udder Health Management Summary and Report. This has been developed over the last two years through a partnership with the School of Veterinary Medicine at the UW. Users of Wisgraph will be familiar with the changes in the SCC analysis, but for those that have not used that tool, we are only too happy to help and answer any questions you may have. We have prepared a pps file to help you compare what the new summary does compared with the old report and with DC305 report functions. We believe that it is a significant improvement over existing analyses and the concepts have been field tested over the last 8 years as we have successfully helped solve milk quality problems on Wisconsin dairy farms. We hope you find it of use to you in the field as you assist farmers in improving their milk quality.

Link to: PowerPoint slide show

Link to: Handout pdf (6 slides per page)

Regards
Nigel Cook

Nigel B. Cook BSc BVSc Cert CHP DBR Dip. ECBHM MRCVS
Clinical Associate Professor in Food Animal Production Medicine
University of Wisconsin-Madison
School of Veterinary Medicine
2015 Linden Drive
Madison
Wisconsin 53706-1102
Tel: 608 265 4981
Fax: 608 262 8595
Web Site: http://www.vetmed.wisc.edu/dms/fapm/index.html

"We don't make the cows, we make them happier!"

The cleanliness of udders is one of the measures most highly correlated with mastitis risk and somatic cell counts.  This paper presented at the annual NMC meeting by Dr. Nigel Cook from the UW vet school provides a variety of methods for quantifying udder hygine and some case studies to illustrate their use in the field.    

http://www.uwex.edu/uwmril/pdf/MilkMachine/Cleaning/07%20NMC%20Hygiene%20Toolbox[1].pdf