Bovine Mastitis can be defined as the inflammation of the udder of a cow resulting from injury or more commonly from bacterial infection.

Collecting milk samples for mastitis testing

Determining which bugs are responsible for mastitis allows the most appropriate tubes and injections to be used; this should improve clinical outcomes and reduce treatment costs. It may also give clues as to how the mastitis is spreading, and hence where efforts should be concentrated to prevent further cases.

The quality of the results depends on the quality of the samples and attention to detail is really important.

The following procedure should give good results.

1. Make sure you have clean hands. Wash and dry if necessary, or ideally wear clean gloves.
2. Wash and thoroughly dry the teat if it appears dirty.
3. Strip out and discard the first 4-6 squirts, thus flushing out non-mastitis causing bacteria from the teat canal.
4. Thoroughly rub the teat end with a medicated swab or cotton wool swab soaked in surgical spirit. Repeat until the swabs remain clean.
5. Take the top off the bottle using the little finger of your left hand then hold the bottle between the thumb and first finger of your left hand. Make sure the internal surface of the lid is always facing down. .
6. Hold the bottle nearly horizontally. If the bottle is held vertically there is a much greater risk of dirt falling into the bottle. One good ‘draw’ of milk is sufficient. It is not necessary to fill the bottle.
7. Replace the cap and label the bottle with cow identity, quarter, date and farm name.
8. Store the sample in a fridge (+4 degrees C) until it can be transported to a laboratory. Storage for up to 72 hours is acceptable. Freezing reduces bacterial numbers but can still give useful results depending on which bugs are involved. Your vet may recommend this anyway.

Managing high somatic cell counts

The chances or achieving a cure for a quarter with a persistently high somatic cell count at drying off varies according to a number of factors, in particular the bacteria causing the infection. These factors are considered on another page of the website.

Culling will unfortunately play a role in the control of high SCC but there are alternatives for many cows.

Alternatives, but please speak to your vet first:

Inject with antibiotics at drying off
Dry off at the normal time but use Zactran® as well as a dry cow tube. Do not use Zactran® if the cow is due to calve within 60 days as there is a risk a bulk tank failure. Use Tylan® instead as long as she is not due to calve within 28 days of drying off. Use a long-acting dry cow tube such as Cepravin DC® (54 days) or Orbenin Extra DC® (49 days).

Dry off early
Dry off early and inject with Zactran® as above. Again, use a long acting dry cow tube. A longer dry period, long-acting tubes and an injection of Zactran® will increase the chance of clearing infection from a quarter.

Dry off the affected quarter
Dry off the affected quarter early. Identify the offending quarter using the CMT. Dry off by infusing 120ml of Povidone iodine into the quarter. An applicator for intranasal vaccines works well for this. The quarter often returns to milk in the next lactation. Give Metacam® to reduce discomfort.

Give affected quarter a mini dry period
The udder is most susceptible to antibiotics during the dry period but they may be effective during lactation.

Option 1: Treat high SCC quarters with Pirsue® once daily for 8 days. Milk withdrawal is 5 days. (Licensed.)

Option 2: Treat with Orbenin LA®; one tube every 48 hours; three tubes; 84 hours withdrawal. (Licensed.)

Option 3: Infuse a Cephaguard DC® tube into the affected quarter. Stop milking the affected quarter. Withhold milk from all quarters for one week. Test for antibiotic residue. Withhold milk from the affected quarter for another week. Test for antibiotic residue. (This option is not licensed.)

(Some of the treatment options described above are not licensed. They cannot therefore be recommended generally and should only be used when specifically advised by a veterinary surgeon. Consider putting time aside to discuss with your vet which options to use and when.)

Micotil® has been widely used as a drying off injection but can now only be administered by a vet. Zactran® is suggested here as an alternative to Micotil® when it is not feasible for a vet to inject Micotil®.

Doses:

• Zactran® – 1ml per 25kg under the skin
• Micotil® – 1ml per 30kg under the skin
• Metacam® – 1ml per 40kg under the skin
• Tylan® – 100ml per cow given under the skin in two site (50ml per site)

Other considerations

• The use of a teat sealant is also generally recommended but is not likely to help reduce high somatic cell counts due to contagious mastitis organisms.
• Use dry cow tubes with extended cover if possible
• Consider having a separate group of high SCC cows and milk them last. The high cell count in the bulk tank is not the only problem. High SCC cows are source of infection for other cows in the herd.
• Flush the clusters after milking high SCC cows with paracetic acid diluted 1:200
• Wear latex gloves when milking
• Post dip