Why Calcium Actually Matters (And Why Most Boluses Fall Short)
Here's the thing with calcium boluses - most of them are designed to dissolve fast and hit the cow with a calcium spike. That's why they all tell you to "give another bolus at 12 hours" - because that's about as long as their calcium delivery lasts. The trials prove it.
Cow Start Complete works differently. The bolus matrix dissolves in two phases and carries a much higher calcium payload than standard boluses. Between the right calcium specification, the controlled dissolve rate, and how the calcium sources actually get absorbed, you get calcium delivery for a full 48 hours. That's why you only need one dose (2 boluses) straight after calving - job done.
THE DATA THAT BACKS THIS UP:
The most recent trial (published November 2024) from Anchor Life Sciences and vets at University College Dublin tested Cow Start Complete on 26 cows from a 280-cow pasture-fed Irish herd producing around 6,600kg per season (21L/cow/day). The results were clear: one dose of Cow Start keeps supplying calcium long after a short-acting bolus has packed it in.
WHY THOSE FIRST DAYS ARE CRITICAL:
We know inadequate calcium in those critical first days post-calving is linked to disease risk, poor immune function, energy problems, reduced rumination, and lower milk production. Just 2 days of low calcium can affect the cow's entire season.
The numbers don't lie:
Subclinical hypocalcaemia (low calcium without going down) causes a 7% production loss
Clinical milk fever hits you with a 14% loss
A recent NZ study showed that between 60-80% of multiparous cows have low calcium immediately after calving, and around 30% are still low at day 3. It's these persistent subclinical cows that have the most issues down the track.
THE BOTTOM LINE:
The cow's homeostatic mechanisms need time to catch up and get her functioning normally again. You need to deliver adequate calcium right through those critical days - not just a quick hit that runs out halfway through. That's the difference between setting cows up for success and leaving them to battle through on their own.
References:
Wilms, J. et al. Journal of Dairy Research 2022, Vol. 89, (1), pp 29-36
Verhoef, W. et al. Veterinary Medicine: Research & Reports 2021, 12, pp 23-32
Martinez, N. et al. J. Dairy Sci. 2016, Vol. 99, (10) pp 8397 - 8416
Lawlor, J. et al. Animal & Veterinary Sciences 2024 Vol. 12, (6), pp 154-160.
Fahey, A., Lawlor. J., Cow Start Research Meta-analysis, 2022
Goff, J P. et al J. Dairy Sci. 2020, Vol. 103: 2591 - 2601
Dairy NZ/Milk-Fever
Roberts, K I., et al. New Zealand Vet Journal 2018