Grade Buster Approach

Using the Grade Buster approach to mastitis control that was pioneered at Franklin Vets

 

We can provide solutions to high somatic cell counts, clinical mastitis, milk grading problems and advice on dry cow therapy.

 

The principals of Franklin Vets are regularly involved in post graduate teaching in mastitis control.

 

Dry Cow Therapy Why & What to use?

It is important to ensure optimal udder health in part through clearing bacterial infection for the next lactation.  Curing existing udder infections and preventing new ones is where dry cow therapy comes in.

Antibiotic DCT is used to cure existing bacterial infections.  Cows with ICSCC>150,000 and heifers with ICSCC>120,000 at any herd test during the season are deemed to be at risk of harbouring a significant bacterial infection.  (These figures were derived from NZ studies completed by R Holdaway in the late 80's and early 90's).

Antibiotic DCT also prevents new udder infections over the dry period by the physical presence of antibiotic in the udder; and also by increasing the rate of keratin test plug formation sealing the dry quarter against outside contamination.
The keratin plug is very important in preventing new infection in dry cows.  However, as calving approaches, teats start to lose their keratin plugs in preparation for milk flow, even in cows treated with antibiotic DCT.  The advent of teat sealants provides a very useful tool in the prevention of new infections over the whole dry period.

All well manufactured DCT products effectively clear the majority of infections in the typical NZ herd at the end of the season.  Even the shortest short-acting products are active in the udder in excess of 21 days, enough time to drive cure rates above 80% for most bacteria.  However short-acting product activity drops off relatively quickly so that after five or six weeks prevention of infection in the udder relies more on keratin plug integrity than the presence or absence of antibiotic.  In a cow with an 8-10 week dry period this decrease in activity usually coincides with the increased infection risk as teats start to open in preparation for the new lactation and with time spent on feed pads or stand-off areas where contamination is an issue.  This is where long-acting therapy or combination therapy with a teat-sealant comes into its own.

Long-acting therapy or combination therapy provides a good "kill" at the end of the season and also good prevention out to ten weeks.  Where the dry period is going to be substantially longer than ten weeks, combination therapy with a teat-sealant will provide protection for the duration of the whole period.

The key information to enable your vet to correctly prescribe DCT for your farm includes:

• the number of cases of mastitis in the first week following calving;
• herd test cell count information;
• bacterial culture results (make sure your bugs are susceptible to the drugs);
• length of dry period; with-holding periods;
• the approach of staff inserting DCT to hygiene and detail.

All DCT products should be administered according to strict hygiene protocols set out in the packaging as the consequences of taking short cuts can be more severe for some products than others.

Combination therapy for mastitis almost halves culling rate

In a recent major New Zealand trial into the treatment of clinical mastitis, culling rates were almost halved by using combination therapy.  In the trial results of combination therapy (where an antibiotic and non-steroidal anti-inflammatory (NSAID) are combined) were compared with the results of using the antibiotic alone.

The trial included herds from Waikato, Southland and Canterbury.  The large enrolment of 727 cows ensured robust and relevant findings.

In the study, the results of treating with a course of the injectible antibiotic Mamyzin vs a combination of Mamyzin and one injection of NSAID, Metacam 20 were compared.

The combination treatment reduced the culling rate by 41%.

The results of the trail were clear cut.  The culling rate for the cows receiving combination therapy was 16% while the culling rate in the cows receiving antibiotic alone group was 28%.  This is a highly significant 41% reduction in culling rate.

Faster SCC recovery

In addition to the culling reduction, there was also a significantly faster decrease in Somatic Cell Counts of the affected quarters, ensuring a speedier return to quality milk production.

Surprisingly there was no difference in milk yield between the treatments.

These findings suggest that despite increased treatment costs, there are worthwhile economic benefits (around 4:1 return on investment) to be gained from using Metacam"20 in conjunction with an antibiotic for treating routine mastitis.

Please discuss with our veterinarian whether combination therapy has a role in your herd this Spring.