Variable silage quality affecting protein levels in milk on farms

The persistent poor weather conditions, which have made grazing conditions challenging, have resulted in many farmers feeding silage for longer than usual on farms.

Consequently, due to the variable quality of silage, there are now reports of very low milk protein levels on some farms.

The protein level in milk is an indication of the cow’s energy levels; in other words, a sudden drop in protein percentages indicates a reduction in dry matter (DM) or energy intake.

Where energy intake is depressed, due to poor-quality pasture or forage – or by receiving insufficient feed – it can result in a cow entering a negative-energy balance, in turn, depressing milk protein content.

In prolonged cases, a cow will use up her bodily fat reserves to compensate for this energy deficit, or ‘milk off her own back’ – leading to rapid body condition score (BCS) loss.

Rapid BCS loss post-calving can cause reduced milk yield, health implications or failure to go back in-calf in the future.

To avoid cows experiencing rapid BCS loss, intakes post calving must be encouraged as much as possible.

To maximise intakes:
  • Ensure fresh, high-quality feed is available;
  • Feed 2kg of pre-calver concentrates to get the rumen working before calving down;
  • Ensure cows have access to fresh clean water at all times;
  • When allocating grass, ensure that a sufficient area is allocated;
  • When feeding silage, ensure an adequate number of feed spaces are available;
  • Milk thin cows once-a-day (OAD), but feed the same as those being milked twice-a-day (TAD).