For many Australian herds, dry-off time for the spring calving cows is now approaching.
For each cow, drying-off is the single biggest opportunity to make a difference.
Not only is it the best chance to change the infection status of a cow, it is also the best chance to reduce the risk of mastitis at the subsequent calving.
Whilst drying-off is commonly considered to be the end of one lactation, it probably should also be thought of as the start of the next lactation!
And because it is usually a significant investment of money, as well as time & effort, it is probably worth doing well!
A successful dry-off program will successfully transition each cow from being a milking cow to being a dry cow, maximise the effectiveness of the dry cow therapy in terms of both the cure of existing infections and the prevention of new infections, and avoid antibiotic residue violations, especially when the cows calve again.
The principle goals of treatment at drying-off are to treat existing infections, and to prevent new infections, both during the dry period and especially at calving.
The key questions regarding treatment are – which cows should be treated, and with what product(s)?
How long is it since you have had a good discussion with your vet about your treatment options?
To have this discussion your vet would like to know some background information, which is likely to include the following –
- What is your Bulk Milk Cell Count history for the last two years?
Are you always in premium? Is it stable, or rising? What are you aiming for?
- What are the mastitis bacteria likely to be in your herd?
Whilst having a set of recent milk cultures as evidence of the mastitis bacteria in the herd would be nice, survey work in Australian herds has shown that the most common subclinical infections in high cell count cows are Strep uberis & Staph aureus.
If you have cultures or a PCR test showing the presence of Strep ag in your herd, you will need special consideration.
- How many, and which cows, are likely to be infected?
If you regularly herd test, then do you have either herd test results, or a cell count summary for your vet to examine?
- Should all cows be treated, or will cows be selected for treatment? If they are to be selected, on what basis will that selection be made?
- How long is your preferred length of the dry period?
It is important to ensure the withhold periods of the products you use will fit with your likely dry period.
- Do you have a history of higher than optimal levels of clinical mastitis around calving?
Countdown suggests that if more than 5% of cows have mastitis within the first two weeks following calving, it is likely to be a significant problem.
- Should you be considering the use of a teat sealant?
Teat sealants can be used both alone, and in combination with antibiotic therapy – what is the best policy for your herd?
- What is the environmental risk likely to be during the subsequent calving period?
Rain and mud at calving time will significantly alter the mastitis risk profile.
- What is your budget?
Cost is always a key factor – are you prepared to spend a bit more at dry-off to reduce the risk of mastitis later on?
The best person to discuss these questions (and any others you may have) will be your vet – they are likely to have the best knowledge of your herd and the local conditions.
The best discussion will be held in the light of some background knowledge – it reduces the amount of “best guesses” that have to be made, and will result in the best decisions for your herd and your situation.