By James Bendle, Davidsons Animal Feeds

For a successful calf rearing programme with heifers calving down at 24months of age, producers need to aim for daily liveweight gains of 0.8-0.9kg per day from birth to ensure target bulling weights of 380kg at 13-15months of age.

Heifers also need a good frame growth but should not be over conditioned.

To achieve such goals, stress at weaning has to be minimised, with any transition in the feed ration done gradually. Producers also need to be mindful of the stress caused with group movements, shed movements or movements to different farms where heifers may be reared. A heifer's ration must be palatable, well-balanced and provide all mineral and vitamin requirements. All to often heifer replacements are challenged with the scraps from the silage pit that producers don't want to feed the milking herd, or later cuts of variable quality forage, which places additional pressure on a heifer's ability to achieve target daily gains.

At this time of year, a lot of replacement heifers are turned out to grass, therefore forage quality and availability has to be considered and whether animals need supplementary feed to ensure growth targets are met.

Whether heifer replacements are housed all year, or have access to grazing during the summer months, their nutritional requirements have to be met to ensure first calving targets.

Assessing forage quality, formulating suitable rations, utilising weight recordings where possible and tracking intakes provides better understanding of heifer performance and where improvements can be made.

Having good quality heifers to replace cows leaving the herd or for fresh heifer sales is an important factor for all, with heifer rearing being the second highest individual cost on any dairy.

Estimates generally lie somewhere around £1650.00 per head, but with well-grown heifers producing more milk, every 50kg in weight below target calving weight is equivalent to a loss of 2kg of milk per day during the first lactation. A clear focus on achieving heifer targets could therefore be worth at least another £180 per heifer over a 305-day first lactation.

To achieve these targets, the Davidsons Performance range of calf and heifer feeds are specifically formulated to develop well framed, healthy, fertile heifers. Using balanced formulations and with a focus on mineral supplementation, the Performance range includes Zinpro@ trace minerals in the form of the Availa 3 package, with 22 feeding trials showing the benefits of Zinpro@ zinc, with daily liveweight gains improving by 3.26% and feed efficiency by more than 4.05%. Younger calves also benefit from supplementation with Availa minerals.

Newly weaned calves eat more, grow faster but still have improved feed efficiency compared to their cohorts fed a standard trace mineral pack. See Figure 1.

The benefits of a bespoke mineral offering for replacement heifers are also seen in improved hoof health and fertility, compared with inorganic minerals. See Figure 2.

A successful heifer rearing programme is key to any business, and having well developed, healthy, fertile heifers entering into the herd should be achievable for all.

For the future success of your herd, can you afford for your heifers not to hit target?