How much grass should I offer freshly-calved cows?

The grazing season will soon be starting on many farms, so to ensure farmers have enough grass to make it to the magic day it is important to ensure cows’ dry matter (DM) intake is controlled.

Cows calving onto a grass-based diet will eat a total DM intake of 8-10kg (grass + concentrates) per day in week one after calving.

Intake will increase by 1kg per week for the first four weeks and 0.5kg per week from week five-to-eight of lactation until they reach peak intake at 17-19kg DM during week 10-to-12 of the their lactation.

A cow will reach her highest daily milk output six-to-eight weeks after calving, with peak DM intake two-to-four weeks behind. The cow will use energy from her fat reserves ‘milking off her back’ to make up the energy deficit for several weeks.

The milking cow should receive adequate quality feed to optimise milk solids production and keep bodyweight loss to less than 0.5 BCS between calving and breeding.

However, if the cow loses too much body condition in early lactation, it can reduce her chances of getting back in calf again.

In spring, the aim is that the cow should graze a high amount of quality grass with appropriate supplementation. When less than 8kg of grass dry matter per cow is available, the deficit should be made up with a forage, as well as concentrate.

This will ensure the cow is getting enough fibre. Stop feeding silage when enough fresh grass is available.

How do I know if an animal’s dry matter intake is low?
1. Excessive body weight loss;
2. Low milk yields;
3. Low milk solids;
4. Poor fertility;
5. Metabolic diseases.