Time and management essential for maiden heifers to achieve targeted mating weights
March 1 is less than a week away, which means that there is only about 45-65 days left before the maiden heifers will be mated. For some, the measurements have already been taken and appropriate management strategies adopted to deal with any lighter maiden heifers.
The target we are striving for here is 60pc of mature liveweight by the start of mating. Table 1 (right) shows the target mating liveweights for herds of differing mature liveweights.
Liveweight and body condition score of the maiden heifer have far more influence than age on calving date, survivability and subsequent milk production. Therefore, achieving these liveweight targets with animals with good body condition scores (BCS) should be a priority in spring. This equates to a BCS of 3. With this target in mind, the critical questions at this stage are:
1. How heavy are your maiden heifers on average and, in particular, what are the weights of the lightest 25pc?
2. Are all your maiden heifers going to hit target liveweight at mating with your present management? Are they better indoors on silage or outdoors on grass?
3. How much liveweight does each heifer, either as individuals or in batches, need to gain to achieve this target and what daily liveweight gain per day is required to do so?
4. Can you get your heifers, especially the lighter ones, out to grass? Is supplementary feed required?
5. Do your heifers need to be divided into smaller groups, with small, lighter heifers fed supplements in order to achieve the required target?