There has recently been an important registration change for teatseal, meaning it is now registered for use in reducing BMCC, as opposed to just preventing clinical mastitis.

Clinical mastitis

Is an infection of the mammary gland which results in;

Heat, redness, pain and swelling in the udder; and/or

Visible changes in the milk (e.g. watery milk, clots, blood) which persist for more than 3 strips of foremilk

Subclinical mastitis

Is an infection of the mammary gland which doesn’t present with any of the signs described above, but results in an increased somatic cell count in the milk. The threshold for defining subclinical mastitis is usually an ICCC =250,000 cells/mL.

Both clinical and subclinical mastitis are associated with significant costs to the dairy farmer. Dairy Australia’s milk quality and mastitis program, Countdown, estimates that the cost of a case of clinical mastitis is $270 on average (although this may be considerably higher depending on milk price and cow production).

The cost of subclinical mastitis is incurred due to reduced milk production, and also the reduced milk price paid by processors for high bulk milk cell count (BMCC) milk. The actual cost varies between farms due to different payment structures, but the diagram below gives you an estimate of the cost of increasing BMCC. For example, if a herd’s BMCC increases from 200,000 cells/mL to 300,000 cells/mL it would cost approximately $119 ($56 + $63) per cow per year, which for a 300 cow herd equates to $35,700 per year.

Australian field trial

A study undertaken in 2014 and 2015 on 8 herds in Victoria and NSW, involved approximately 1500 cows. Cows that were not administered Teatseal (i.e. dry cow antibiotic only) were twice as likely to have subclinical mastitis in the first 60 days of lactation than cows that were administered Teatseal and dry cow antibiotic. The Teatseal group had an estimated average BMCC which was 45,000 cells/mL less than the non-Teatseal group. This difference is similar to the size of the steps in the Countdown diagram, which at any BMCC level represents a large potential saving to the farmer for using Teatseal.

The graph below represents a herd in the Western District of Victoria and illustrates the beneficial effects on the herd’s BMCC after initiating Teatseal use in cows at dry off, in addition to antibiotic dry cow therapy. This graph clearly demonstrates a significant drop in the herd BMCC following the first use of Teatseal in the milking herd, as well as another drop in BMCC the subsequent year, when they began to Teatseal maiden heifers. Importantly, the BMCC has remained low and relatively stable in the subsequent years.