Shorter dry cow periods are only an option for farms where SCC can be carefully managed. However, they do have considerable benefits in reducing cow stress and lengthening the period spent in milk.
For Holmbush Estate, achieving the most milk in the most efficient way from the 370-cow herd is paramount.
Having concentrated on adjusting other key areas of management to suit the system, such as diet and nutrition, they have decided to go down the route of reducing the number of days cows are dry, or considering a shorter dry cow period (SDCP).
The herd has now reduced the dry period from the more traditional 55-60 to 40-45 days, as originally suggested by their nutritionist, Warwick Bastard of Model Nutrition.
There are two main concerns for farmers considering SDCP, he explains. “One is the danger of increased SCC, the other the drop in yields.
“However, the benefits to be had in terms of reduced stress due to a more constant ration and a shorter time in negative energy balance after calving, when managed appropriately, can outweigh any drop in lactation.”
And, as the herd is currently averaging SCCs of between 150-160,000, he maintains in this case he is comfortable in advising SDCP. But for herds with average SCCs of more than 200,000 managing mastitis threat could become difficult.
Shortening the dry period seemed the logical step to achieving more cows in milk, explained herd manager Stephen Barbour. “But we were unsure of how to implement it without the appropriate alternative dry cow therapy treatment.”
The ration is predominantly home-grown on the 344ha (850 acres) with the exception of straights such as rape, soya and molasses, so maximising milk production from forage is essential.
“We grow 50-60 acres of grain maize for crimping, which we clamp rather than ag-bag. This is fed alongside grass and whole-crop in the winter, while rolled wheat is included in the TMR in summer months.
“Having just one group of dry cows means we have reduced pressure on buildings and we can implement a simpler feeding system. Not only did we have separate dry cow groups, each with a different ration, but all replacements are also raised on farm, which meant considerable demands on building space.”
Dry cows are now housed year-round, allowing for better management of diet and environment. And what is lost by not having peak lactation, you gain through the 25 extra days in milk, he adds.
Calving indexes were going the wrong way, reckons Mr Barbour. “So we experimented with shorter periods on younger animals, with every cow that has calved in the past 12 months spending 52 days dry.”
“The change has resulted in fewer dry cows to manage, shorter calving intervals and improved fertility. Shortening the dry period has taken 25 days off our calving interval, from 425 to 400.
“We are now trying to move towards a shorter dry period of between 40-45 days. With dry cows returning immediately to a ration containing concentrates, there have been reduced rumen transition problems thanks to a more consistent feeding regime,” he adds. “Pre-calving heifers join the group two weeks before calving.”
Mr Barbour believes vet partnerships are useful in targeting specific problems or health issues in the herd. “Essentially, the less time vets spend on farm treating cases, the more money they will make, meaning they are willing to spend time initially getting the foundations right.”
Administering a comprehensive dry cow therapy can be tricky, so contract vets Westpoint have given courses to those responsible on the farm as to how to get the most out teat sealant and antibiotic treatment. “Shorter dry periods were something we would never had considered if there wasn’t comprehensive dry cow therapy to back it up.”