Dry cow treatment cuts tricky

With a low payout looming, and possibly another to follow, she acknowledges every cost will be under scrutiny and at $10 or more per cow, dry cow treatments will be no exception.

However, experience and trials show antibiotic dry cow treatments (DCTs) and internal teat sealants (ITSs) are effective tools in managing mastitis and somatic cell count (SCC) so those who decide to cut do so at their peril.

“We recommend all cows get something at drying off so you don’t have to deal with so many problems at calving,” she told Rural News.

“It’s a question of how much clinical mastitis you’re prepared to tolerate, both post drying off, and at calving. Do you really want a bigger antibiotic bill next spring, not to mention the extra work and lost production more mastitis cases mean.”

The first step for anybody looking for savings at drying off should be to consult their vet and consider if sufficient information is available to take a targeted approach to treatments.

“Even if you’re not looking to make cuts, liaising with your vet on the best treatments should be your starting point.”

If it’s known which cows are high cell count cows and/or have clinical mastitis, but overall herd SCC is low, then DCT may be targeted at these, with an ITS treatment in support, while the rest of the herd just get ITS.

As for which DCT to use, Lacy-Hulbert says the range of cure rates is not hugely different so it may be that a middle of the range product is more cost effective than the top of the range.

Getting culture tests done on milk samples to identify which bacteria are responsible for high SCCs or clinical cases will help inform decisions. “But a lot of farms don’t culture so they don’t know what they’re dealing with.”

Freezing samples from mastitis cases at calving saves time at a busy time of year so if such samples were taken, there’s no time to lose in getting them analysed now if it’s not already been done, says Lacy-Hulbert.

Similarly, current high SCC cows or even clinical mastitis cases should be tested without delay. “It typically takes about a week to get results back so it may still be possible to get results before drying off.”

Once a cow is dried off, if no treatment’s used it typically takes about a fortnight for the teat canal to seal so extra vigilance for mastitis cases is needed during this period. Where cows are sent away for grazing shortly after drying off this may not be possible, another good reason for blanket treatment, she points out.

However, treatment itself carries a risk of introducing bugs to the teat canal so even where ITS is used a close eye should be kept on the herd for the next 5-7 days.

“There have been a fair few instances where unhygienic practice has caused some very sick cows and some die. When it does go wrong, it goes spectacularly wrong because the types of mastitis you get are not easy to treat with antibiotics.”

Another factor in the decision about if and what to treat cows with at drying off is the wintering system.

Muddy grazing conditions, particularly with high amounts of faecal matter mixed in, heighten infection risk. Feed pads or wintering barns where cows can’t find somewhere dry to lie also appear to heighten risk.

“There do seem to be more and different sorts of mastitis from these systems; typically more coliforms, though there’s still a lot of strep’ uberis even with these.”

A scientific study is needed to get a clearer picture of what impact such wintering systems are having, she adds.