Over the past year, dairy commodity markets have shown unprecedented volatility, and we have experienced some ingredients, such as skimmed milk powder and sweet whey powder, reaching historically high levels. This coupled with increasing vegetable oil prices means that the cost of calf milk replacer (CMR) has continued to rise, which inevitably adds cost to calf rearing systems.
Read more about switching to whey milk powder here
When reviewing feeding strategies to try and optimise performance and/or manage costs, it is important that we consider the short- and longer-term impacts of changes. For example, it is important to consider the cost associated with preweaning nutrition alongside other costs encountered during the calf and heifer rearing period; for example the impact, consequences and associated costs of health incidences such as scour, or the financial implications of missed growth targets for insemination or calving down.
Ask questions to understand calf milk replacer specifications
There is significant variation in CMR specifications available in the market, this ensures that there is a product available to match the objectives and required price point of different calf rearing systems. Due to the investment, careful consideration should be taken when deciding on type of CMR and appropriate feeding scheme on farm – working with your nutritionist, calf specialist and vet will ensure all information can be collected and considered in order to support an informed decision.
With the increased price of raw materials, it may be suggested that changing CMR products to a cheaper powder may achieve a cost saving per tonne and offer a quick solution to save money. However, it is important to understand how the specifications differ in order to consider the implications that the change may have on practical feeding, calf performance and health as well as long-term animal performance.
The price of CMR (£/tonne) can be reduced in a number of different ways, including:
- Reducing energy content or digestibility – normally through reducing oil levels, this can lead to an increased lactose level and therefore will affect overall osmolality.
- Reducing protein level or protein digestibility – dairy protein sources are increasing in price so including, or increasing the inclusion, of vegetable sources helps to reduce cost. However, be mindful of digestibility differences.
- Reduction or replacement of skimmed milk or whey products, with alternative whey derivatives or lower quality milk-based ingredients.
Read more: The difference between skimmed milk and whey powder digestion
Supporting Calf Performance
The balance between digestible energy and high-quality protein sources provides the nutrients required for calves to achieve performance targets. When reviewing calf milk
replacer specification and feed curves it is important to consider nutrient intake alongside associated costs. For example, moving from a high specification product may reduce cost per litre or cost per calf per day, however, the calf feeding period may need to be extended to achieve target weaning weights.
We should not forget that the environmental factors and health pressures, which can vary in each unit, are crucial considerations. For example, a unit may be achieving low treatment or mortality rates due to the supportive nature of the nutritional strategy, alongside the expert advice from the vet team. If this nutritional strategy is reduced, this can often result in an increase in associated problems arising which in turn can add costs such as veterinary and medical support, staff labour looking after unwell calves and/or prolonged milk feeding period.
Read more about the digestion of skim and whey here
Weaning
It is also important to consider the weaning challenge - supporting adequate performance at weaning is crucial to support the robustness and resilience of calves for upcoming changes that can underpin periods of stress e.g. group changes, housing changes, and diet changes.
So, in summary, it is important that we consider the cost associated with nutrient intake. We can achieve a reduction in the price of the CMR, however, if we are reducing the energy and protein intake to the calf, or the nutrient digestibility, then calf performance (DLWG and/or health) can be affected.
Implications of practical feeding
If we are changing the nutrient makeup of the CMR we are feeding it is important to be mindful of the considerations around practical feeding. Changing specifications or formulations may affect the solubility and physicality of the mixed milk.
A change in digestibility or osmolality of the overall liquid feed may require the feed curve to be tweaked. For example, concentrations may need to be lowered to control the osmolality of the liquid feed and volumes may need to be reviewed to take into account overall nutrient intake.
In some instances, target volumes and speed of volume increase along the feed curve may need to be considered. Recent research has demonstrated that calves regulate their intake of milk replacer based on energy density. It has been shown that calves fed milk replacer where lactose was exchanged for fat exhibited fewer signs of hunger during weaning which may reduce weaning stress.
Consider the environment
Drainage and ventilation should not be forgotten, all calf units are unique and some, therefore, experience different pressure points. When reviewing nutritional strategies, the implications on environmental challenges should be remembered. Increasing volume to match nutrient intake may lead to an increase in shed humidity if drainage is a pinch point.
On many units, it may also be worth reviewing the complete calf rearing strategy. Objectives for rearing replacement heifers and beef calves can be very different therefore considering a change in feeding protocol for different groups can offer a cost-saving solution.
Read more about creating the perfect calf shed environment here
Measure and monitor key performance indicators
Monitoring and managing key performance indicators (KPIs) is essential, if we understand our current performance it allows us to understand the changes that may offer us opportunities to ensure we are being efficient.
Table 1: Overview of calf key performance indicators
| Average Daily Liveweight Gain (DLWG) | >800g, maximising early life growth rates has shown multiple benefits |
| Weaning weight | Minimum of triple birthweight, if being achieved aim for 3.25 |
| 4 weeks post-weaning weight | >2kg/calf/day for three consecutive days |
| Start feed intakes at weaning | *perhaps refer to mortality rates and reference calf health plan with vet? |
| Health incidences/treatment rates | 55-60% of BW for insemination |
| Heifer development | 85-90% of BW for first calving |
| Age at first calving | 22-24 months |
The calf rearing period offers a unique opportunity to capture the potential of enhanced feed conversion efficiency whilst also exploiting the genetic potential of the animal. DLWG will continue to be an important metric, however widening the scope with regards to objectives to consider optimal development, resilience to disease and longevity allows us to take calf rearing to the next level.
LifeStart Science research by Trouw Nutrition has shown that elevating the plane of nutrition pre-weaning not only leads to higher calf growth rates and improves heifer performance. In addition, the latest research demonstrates clear long-term benefits on fertility, survivability and lactation performance providing a clear return on investment.
