What is the Calcium Deficiency Challenge?
Modern challenges to cow productivity
New challenges to cow management are a direct result of higher productivity in modern herds – particularly those challenges occurring during the transition period. As any herd manager knows, getting this wrong affects the whole cycle of milk production, fertility and overall herd performance.
As an example of these challenges, typically, clinically diagnosed milk fever incidence of 10% within a herd can actually reflect an unseen but far more serious 60% subclinical challenge.
Immunity is naturally suppressed around the time of calving, which makes the cow more susceptible to disease.
Negative energy balance
Cows require a lot of energy to produce milk in early lactation. When dry matter intake falls behind in this period, they have to mobilise excessive body fat, leading to ketosis
As milk production levels have risen over the past years, fertility levels have decreased. This could originate from an increase in negative energy balance and a shorter oestrus period. As a consequence the chances of a cow getting back in calf are reduced.
One of the biggest headaches professional dairy farmers face today – and a major threat to the overall performance of the herd is the Calcium Deficiency Challenge.
During the period immediately post calving, cows often fail to absorb sufficient calcium from their feed to meet the immediate demands for milk production, leading to:
Both visible and invisible milk fever
Reduced feed intake
A decline in herd milk production
Milk fever – the reality in most herds
Most dairy farms have reported cases of milk fever. The incidence of clinical milk fever on a normal dairy farm is estimated to be around 10% while subclinical milk fever may have a much higher incidence of 30% to 60%. This challenge is now critical to manage in modern herds as it significantly increases the risk of other production diseases like ketosis.
Over 90% of the cases of milk fever are known to occur in the first two days after calving, a very narrow time frame. In this period, the cow cannot react fast enough to cover their dramatically increased calcium requirements.
The cow has three ways of increasing her calcium supply:
- Decreased urinary calcium excretion.
- Increased calcium mobilisation from the bones.
- Increased calcium absorption from the intestine.
Why are cows so vulnerable?
Dairy cows often receive too much calcium from the basic components in their dry cow diet. This leads to limited natural absorption of calcium in the intestinal tract. If not corrected in the dry period the natural absorption mechanism becomes too slow to provide the cow with the calcium she needs once lactation starts.
In the three weeks prior to calving, cows must accelerate this natural process of utilising calcium from their feed within the GI Tract. This is a significant issue for modern transition cow management and can be defined as the Calcium Deficiency Challenge.
Without careful management and an alternative feed programme, cows can become vulnerable, weak and susceptible to numerous production challenges.