These treatments contain long-acting antibiotics to treat cows with existing cases of mastitis and prevent new infections from developing during the dry period. They should only be used immediately after the last milking of a cow’s lactation and should not be used to treat quarters or cows that have been dried off previously.
Internal teat sealants are another option for use at dry-off. These don’t contain antibiotics, so more care must be taken when introducing them into the cow’s teat.
Teat sealants can be used in combination with antibiotic dry cow treatments to extend mastitis prevention during the dry period and before calving. The product should only be administered after the last milking of lactation and immediately after dry cow treatments, if being used in combination.
In some situations internal teat sealants may be used without dry cow treatments, but only after careful evaluation with a vet.
Dry cow therapy (DCT) is an essential part of mastitis management, and when done properly, can add tremendous benefits to long-term milk quality. Deciding which cows to treat with what dry cow option is a key part of working with your vet towards improving your bottom line.
Quick tips for using DCT and teat sealants
Administering DCT and teat sealants present some hazards, for cows and people.
- Bacteria can be easily introduced into the teat if the teat end is not disinfected properly or tubes become contaminated. Infection by these environmental bacteria can cause severe mastitis. In some cases, sickness or death of the cow can occur
- People can be injured by cows during administration of DCT, so take your time and have help
- Antibiotic residues in milk and meat (including calves) need to be avoided by observing the correct number of tubes used, minimum dry periods and correct withholding period after calving.
To minimise hazards and costly mistakes:
1. Plan the day and people required
Administering DCT or internal teat sealants is difficult and requires time and effort. Make sure all operators have been adequately trained and are supervised well. A step-by-step reminder of the correct disinfecting and insertion technique is illustrated (right). In large herds, dry off cows in batches over a few days, so the task is more manageable e.g. last two to three rows over three or four days. Work on the basis that one person can handle about 20 cows per hour and that extra people may be required to restrain cows, especially if cows are not used to having their teats handled.
2. Make sure strict hygiene is used
To avoid introducing bacteria into the teat, each teat end must be thoroughly cleaned with a cotton wool ball soaked in 70 percent meths or teat wipes prior to insertion of the treatment tube. When treating all four teats, clean teats furthest from you first, before nearer teats. To avoid accidentally contaminating previously disinfected teats, treat nearest teats before far teats. Make sure that tubes stay clean and dry before use. Some people find it helpful to warm tubes (especially teat sealants) before use. If so, place them in the hot water cupboard overnight or place the bucket of tubes inside a second container of hot water. Make sure the tubes stay dry and NEVER come into contact with water or dirt before use.
3. Avoid over-treating cows
Due to the repetitive nature of treating cows with dry cow products, mistakes can easily occur. To avoid over-treating individual cows, only take four tubes to each cow and use the same order to treat the quarters e.g. left back, right back, left front, right front. If different treatments are being applied to different batches of cows, draft out and group the cows the day before, according to treatment approach. This way, all cows in a particular group can be treated in the same way.
4. Apply MRS T
The steps in MRS T (mark, record, separate and treat) can also be applied to DCT, after the cow’s last milking.
MARK cows that are dried off early and receive DCT
The risk of inhibitory grades increases markedly for herds which treat cows with DCT prior to the rest of the herd being dried off. Mark these cows with a different colour to the mastitis treatment system, spray them copiously (tails, legs and rump!) and load them into the electronic system, if available, to ensure they don’t get milked by mistake. Re-mark cows every two weeks as the marks fade.
RECORD details of all cows being treated with DCT
Make sure that paper and electronic records are updated promptly. If still milking other cows, a list of early DCT-treated cows on the farm dairy whiteboard will help reduce the chance of cups being put on a DCT-treated cow.
SEPARATE out cows to be treated with DCT
When drying off batches of cows, don’t treat cows with DCT whilst still milking other cows. Wait until milking is finished, the pipe is out of the bulk tank and the milking cows have been shut away, before bringing the cows back into the dairy for treating with DCT. These DCT-treated cows should be wellmarked and grazed in a different part of the farm for the next few weeks to avoid costly mistakes.
TREAT only after thorough disinfecting of the teat end
The easy-to-follow-guide (right) from DairyNZ’s SmartSAMM Healthy Udder illustrates the correct technique for giving intramammary treatments to cows.
This article was originally published in Inside Dairy March 2011