Udder health is about mastitis, which means an infection of the udder, resulting in heat, swelling and changes in the milk. Mastitis can be visible (clinical) or invisible (subclinical).

Mastitis can lead to loss of production, due to losses during the course of treatment and due to lower production in the infected quarter during the current and even future lactations. Some infections will cause permanent infection which means that those udders can shed bacteria and infect other cows.

In NZ the two common causes for mastitis in dairy cows are Streptococcus uberis  (spring mastitis) and Staphyloccus aureus. Streptococcus uberis causes a peak of mastitis cases around calving, especially when cows and heifers are calving in wet conditions. Sensitivity is normally very good, so proper treatment should result in a good cure rate. Staphylococcus aureus causes mastitis during the full length of lactation. Due to different sensitivity patterns and due to fact that S. aureus manages to hide in the udder tissue cure rates after treatment tend to be lower, resulting in more cows chronically infected with high cell counts.

Identification of the main causes for mastitis on a dairy farm is the starting point for a planned approach to manage mastitis. Management of mastitis involves farm specific treatment plans, dry cow therapy (with or without Teatseal), managing springer mobs, close up rations for springing cows, milk plant maintenance, early detection of clinical mastitis, teatspraying after milking of all cows all season, etc.

There is no "silver bullet" solving mastitis problems on a dairy farm, just proper management all year round.