Dry cow mastitis
May 2023

By now a lot of you will have dried off or have dried off some of the herd. With most of the cows treated with dry cow therapy and/or teat sealant, dry cow mastitis should be minimal but it is important to detect early.

Udder infections of dry cows are most likely to occur immediately following dry off and around calving, cows are susceptible to new infections especially in the first week of the dry period before the teat plugs have formed.

In the first few days after dry off cows should be checked carefully in the paddock for signs of sickness ie swollen udder, difficulty walking or off their feed. Pay particular attention to cows that received teat seal only as they can develop a very acute mastitis very quickly!

Affected cows should be brought to the shed and the affected quarter fully stripped out. It takes time to do this well, but the less pus and rubbish left in the udder, the better the antibiotics will work and the greater chance you have of saving the quarter(s). Stripping out should continue at least daily for the duration of the treatment.

Most dry cow mastitis is caused by an environmental bacteria, predominantly Strep. Uberis. Occasionally, cows can get sick as a result of mastitis and this can be the result of Coliforms, Staph. aureus or Clostridial bacteria infecting the udder. If the cow is sick, it is recommended that you call the vet ASAP, as these cows often go downhill rapidly from the toxin build-up and can be dead within 24hours if left untreated. Fluid supplementation and anti inflammatory medication  is often the most important aspect of treatment in these cases.

Treatments should be discussed with your vet, but in general selecting an injectable mastitis treatment will be better than simply using an intramammary. This is because when cows are dry, there is no milk for the intramammary treatment to diffuse through and get dispersed up into the udder.

Dry cow mastitis, as with any other mastitis, is a painful condition, and therefore adding in a non-steroidal anti-inflammatory (e.g. Metacam) is strongly recommended. This is especially important if the cow appears sick.

When you have finished the treatment don’t be tempted to insert a tube of Dry Cow antibiotic up the affected quarter, these cows are dried-off and don’t have the milk present for dispersal of the drug through the quarter and have a high risk of giving an antibiotic grade at the start of next season.

Run all cows through the shed for a manual check of the udder after 14 days, this should be done for the first 4-6 weeks of the dry period , new clinical cases are most likely to be found within the first 28 days of dry off.