In the weeks post-calving, cows will produce more milk than their feed intake can provide for, resulting in Body Condition loss due to Negative Energy Balance. A cow typically reaches peak milk output 6-8 weeks post-calving but will only reach peak dry matter intake 10-12 weeks after calving. However, the success of breeding 2024 is mainly dictated by the severity and duration of this period of NEB during the weeks post-calving.

NEB will firstly appear in the form of low milk protein % in the short term and in the more long-term have detrimental consequences on fertility during the breeding season. The overall objective is to have calved down the cow at a BCS of 3.25 and maintain an average herd BCS of 3.0 (range 2.75 – 3.25) at the start of breeding, to achieve optimal fertility.

Keeping body condition loss to less than 0.5 BCS between calving and breeding has proven to significantly increase the likelihood of conception to first service, with cows that lost <0.5 body condition score between calving and breeding typically shown to ovulate 15 days sooner, than cows which lost >1 BCS.

In very practical terms, this means bridging and filling the energy gap between what the cow outputs relative to what is put into her in regard to feed. Forage quality (which is lower in many cases after the difficult 2023 silage season) and getting high quality grass into the diet will be the main dictating factors here.

After this, most of the energy deficit will have to be filled via concentrates in the parlour, with milk output coupled with silage analysis and ability to get to grass, dictating feeding rates this spring.

For more information, contact your local Agritech Sales Advisor. 

With many cows dried off this month, the focus in most yards is on correct dry cow management. However, we must consider nutrition plans for cows calving down for the coming spring.

Several key factors directly correlate to the success of the calving season, including:

1. A planned and well executed dry cow mineral programme.
2. Calving down the cow in the correct body condition score.
3. Excellent animal husbandry in the week’s pre and post-calving (no additional stressors).
4. Careful transition diet planning.

Fast forward to late January/February, especially given how silage quality was hampered by the weather this year: do we have sufficient high-quality forage available for when cows calve down/and if not, what is the plan of action?

Negative Energy Balance

In the weeks post-calving, cows will always produce more milk than their feed intake can provide for, resulting in Body Condition loss due to Negative Energy Balance. For example, a cow will typically reach peak milk output 6-8 weeks post-calving but will only reach peak dry matter intake 10-12 weeks after calving. The freshly calved cow’s diet must be sufficient to keep body weight loss to less than 0.5 Body Condition Score (BCS) between calving and breeding.

Dry matter intake typically increases by 0.75 – 1.0 kg/week post-calving – highlighting the need for an energy-dense transition diet. This can be difficult to control where silage quality is compromised. Where a deficit occurs, we must be prepared to fill the gap, or issues such as poor fertility will come into effect in May. Adequate concentrate supplementation will be paramount (dependent on milk output), along with the inclusion of high-energy grazed grass in the diet.

Monitoring NEB on Farm

1. Falling/low milk protein % (signalling energy restriction in the diet – caused by poor quality silage, delayed turnout and/or insufficient supplementation levels relative to cow output).
2. Body condition loss across the herd (>25% of cows with a >0.5 unit of BCS loss in early lactation).
3. A bulk tank milk fat: protein ratio > 1.4 (calculated by dividing the milk fat % by milk protein %) signals poor energy balance in the herd’s diet.

Further Advice:

For more information, contact your local Agritech Sales Advisor.

Research has shown that calves reach similar weight gains on milk replacer as they do while being fed on whole milk. However, this is on the basis that the milk replacer is formulated correctly, using high quality dairy ingredients and that feeding instructions are followed. Milk replacer labelling and composition can, at times, be confusing, with large differences in specifications and price available on the market. However, it is important to keep several factors in mind when selecting a milk replacer to fit your system and to avoid any confusion.

Protein Sources

Many questions center around the percentage of protein on the label of a bag of milk replacer, which is important, but more emphasis needs to be placed on the origin of said protein %. As we are trying to replicate the role of whole milk, as much of the protein as possible should be coming from a milk/dairy-based source, relative to vegetable/plant-based sources. In a young calf’s first few weeks of life, dairy sources are much more digestible and result in greater performance. Plant-based protein sources are cheaper alternative sources of protein and where inclusions are high, similar levels of performance to whole milk should not be expected in early life. Increased fibre content can often be indicative of plant derivatives being used in milk replacers.

Manufacturing Processes

Another less considered factor in overall digestibility of a milk replacer is the quality of the raw dairy materials used. Low heat-treated milk powders will have natural immunoglobin content available in the product and have no protein denaturisation, relative to high heat-treated skim or whey. Low heat-treated milk products are often more expensive on the market, but again lead to increased performance/digestibility.

Fat Sources

Fat percentage and sources of fat in milk replacer are also important, as fat is the main source of energy to the calf. Coconut and palm fat are the more common sources, with great digestibility and energy respectively for young calves.

Feeding Rates

The percentage of solids in whole milk is typically 12.5% (approx), hence it is also the most common feeding rate of milk replacer on the farm. This equates to 125g of powder in 875ml water to make up 1L of feed. Fed at 6L, a calf will be consuming 750g of milk replacer daily.

Accelerated feed programmes are often used on farm where higher Average Daily Gain (ADG) is being targeted with replacement heifers – this would include feeding a higher concentration of milk replacer (5% milk solids) or increased volumes. Once-a-day feeding schedules are becoming increasingly popular. However, once a day feeding should only ever be considered once calves are greater than one month old.

Weaning should be gradual and only ever considered once a calf is consuming more than 1.5kg/hd/day in group pen scenarios. At this point, a calf is independently consuming enough dry matter from straw and concentrate to allow for a stress-free weaning period.

Learn more about our Vitalac Calf Milk Replacer Range here. 

For more information, contact your local Agritech Sales Advisor.