Cows are moving closer to calving, and for the most part are entering into the time frame known as the ‘transition period.’
Getting the management of cows right during this period is vital, in order to ensure that cows calf down and enter lactation, without being affected by metabolic issues.
The transition period is defined as the time periods of three weeks pre-calving and three weeks post-calving.
During these time periods, cows face many physiological challenges.
Transition period
To prevent issues with cows during the transition period, there are a number of key areas to focus on.
Cows at the highest risk of metabolic issue, are those that are not in the ideal body condition score (BCS) prior to calving.
A spring-calving cow should be in a BCS of 3.0 at calving – anything above or below this figure will lead to an increased risk of developing one of the issues outlined above.
If there are some cows that you believe to be in too low of a BCS, you must watch them closely. Improving the condition of these cows is almost impossible at this time of year.
Examples of issues that can arise during the transition period include: Udder oedema; milk fever; retained placenta; displaced abomasum (stomach); laminitis; metritis; ketosis; and fatty liver syndrome – all of which result in lost profits.
Having cows in the correct mineral status is also important during the dry period, as it will help to prevent milk fever and associated problems, such as a slow-calving, retained placenta, ketosis and displaced abomasum.
Dry cow minerals should be fed to cows for at least six weeks prior to the start of calving.
It is important to discuss the mineral requirements of your cows with your vet.
The mineral make-up of the forage being fed to the cows needs to be considered, and it should be of high-quality.
Dietary calcium levels should be kept low pre-calving. The risk of milk fever is reduced if dietary calcium levels can be maintained below 0.5% of dry matter (DM) before calving.
Minerals are usually fed at a rate of 120g/cow/day, if you are dusting minerals on silage, it is better to do it twice-a-day at a rate of 60g.
Issues
Most of the issues associated with the transition period will arise shortly before and after calving. Although treatment is carried out, the impact of this issue can last throughout the duration of lactation.
E.g., a cow with milk fever is eight times more likely to develop mastitis early in lactation.
The management of cows during this period is vital, as it will ensure that cows have a successful transition from late-pregnancy to early-lactation.
Getting through the calving season with any cows being affected by a metabolic issue is unlikely, but getting the management right should greatly reduce the number of cases and severity of these cases.