The dry period is the time where we give our cows time to recharge. They gain condition, the udder gets a break and their feet recover through less walking and less exposure to hard surfaces.
As most farmers know, mature cows need to calve in body condition score (BCS) 5 and first and second calvers in BCS 5.5. These targets are based on production and reproductive benefits associated with these calving BCS. Cows in their last month of gestation will not gain BCS because of the energy requirements of the growing calf.
To optimise the transition period we need cows in the right BCS and we need energy allocation to be correct:
- for her stage of gestation (is she calving this week or in a month?)
- for her BCS (if she is a mature cow and is in BCS 5 or greater then she can be offered 90% of requirements, if she is a mature cow less than BCS 5 or if she is a heifer, then she needs to be offered 100% of requirements)
- for her live weight (size/breed)
- to allow for food wastage appropriately.
Getting the transition period right isn’t just important for production and reproduction, there are also factors that influence the chance of developing lameness: body condition score (BCS) and the calving effect.
What does BSC have to do with lameness?
One of the structures in the hoof is the digital cushion. The purpose of this structure is to dissipate force and transfer the load to the wall of the claw.
Body condition influences the fat content of this cushion. When BCS decreases, so does the size of the digital cushion, reducing its functionality and predisposing to lameness. Lame cows then eat less, reducing BCS further, causing a vicious circle. Chicken or egg? Studies have shown that reduction in BCS precedes lameness.
So not only does BCS impact production and reproduction, it also affects the lameness risk. What are you waiting for? Get the herd scored and act according to the findings!
Calving effect and sore feet – what is the link?
Calving/birth is such a routine part of dairy farming that we take it for granted and don’t often stop and think about what a remarkable and impossibly destructive process this actually is.
All the ligaments and connective tissue in and around the reproductive tract have to be degraded for this process to be able to take place. Now visualise this for a moment and then consider: the things that allow the calf to go through the pelvis affect these same structures in the hoof!
The ligaments and connective tissue that keep the hoof wall, the sole and bones together in a stable position, lose their strength in the week(s) leading up to calving and do not return to full strength until about 3-4 weeks after! On top of that, cows are only designed to walk on soft surfaces and stand on soft surfaces.
From the hoof’s point of view the worst case scenario is to:
- come out of a period with less walking (aka dry period)
- then have to transition to long walks to the dairy and standing on concrete when the structures in the hoof are at their weakest (the calving effect)
This gets exacerbated when they have to walk:
- on poorly designed or maintained tracks and races
- while being pushed on races (pecking order, especially in heifers!)
- or stand on the yard while under pressure: heads go up which means they can’t choose their footing and might stand on a rock or a slippery surface
In summary, most of the lameness seen in cows 2-3 months post calving, completely traces back to this calving effect (exacerbated by the stockmanship and facilities = the environment).
Recent research has shown that you can pre-condition feet, by making sure animals walk before the calving effect kicks in. Cows have an in-built digital cushion that thickens when walking more (the same one that reduces in size during weightloss). Farms that bring their heifers home in May and run them with the late calvers/milkers have less lameness post calving. This strategy would help with socialising heifers and reducing stress post calving as well, because they are used to cows, concrete and routine.
- Help your cows gain weight to reach target BCS at calving
- keep your cows fit, especially heifers that are not used to walking long distances and standing on concrete.
For herds that condition score regularly, recording individual cow condition scores at the planned start of calving are crucial for documenting the starting point for the season. If you would like your herd condition scored pre-calving get in touch with your Vet. There are numerous body condition score accredited vets within Anexa who can help.