Calcitrace D3 is an oral bolus, containing a high level of calcium as well as magnesium, phosphate and Vitamin D3. It is for use in dairy cows at risk of developing milk fever around the calving period. Calcitrace D3 can also be used following successful treatment of milk fever by calcium injection to help maintain normal calcium balance.

Each pack contains 4 and 12 boluses.
Each 204g bolus provides:
43g Calcium
5g Magnesium
3g Phosphorus
100,000iu Vitamin D3

Uses
To be used in dairy cows at risk of developing hypocalcaemia (milk fever) – especially high yielding, multiparous dairy cows and those with a history of developing the condition. 
For reduction of milk fever:
Give one bolus at the first signs of parturition to provide sustained calcium levels for up to 48 hours.
If necessary repeat with a second bolus 24 hours after administration of the first bolus, for high risk cows (Provided that cows can raise their head and are starting to eat and drink).
For supplementation following calcium injection:
Give one bolus 2-3 hours after calcium injection. Repeat with a second bolus 24 hours later if necessary.
Only administer Calcitrace D3 using the approved applicator.
It is recommended that a veterinary surgeons advice is sought before use

Dosage & Administration
After administration the gelatin capsule quickly dissolves to release the minerals into the rumen. Calcitrace D3 delivers a massive 43g of available calcium in each bolus. The calcium is released into the blood of the animal for up to 48 hours. The calcium chloride provides an immediate surge of calcium, followed by the more sustained release of calcium provided by the calcium phosphate and calcium sulphate. Each bolus also releases phosphate, magnesium and Vitamin D3 which encourage normal blood levels and aid in the animals calcium control.

• Calcium chloride (fast release calcium)
• Calcium sulphate (slow release calcium)
• Calcium phosphate (slow release calcium)
• Magnesium (to support magnesium levels)
• Phosphate (to support phosphate levels)
• Vitamin D3 (to aid calcium absorption from the gut)

Each bolus also has an acidifying effect, much like a DCAD diet has, which helps the cow to mobilise her own calcium reserves. 

4 x 204g boluses 

Please see below link to the Veterinary Medicines Product Information Database
http://www.vmd.defra.gov.uk/productinformationdatabase/Default.aspx