Rumenco has said farmers should consider giving upland ewes on marginal grazing a mid-pregnancy protein supplement.

The livestock feed supplier said before leaving upland ewes to be left fully reliant on grazing until lambing, farmers should consider providing them with a protein supplement to prevent placental development issues.

Especially in the late autumn and winter period, high fibrous forage is low in protein and hard to digest, Rumenco said.

When energy and protein requirements aren’t met in pregnant ewes, body condition, foetal development and placental development suffer as a consequence.

Rumenco nutritionist, Dr. Alison Bond, said: “While one of the biggest benefits of an upland system is having a hardy, low maintenance ewe who can thrive on marginal forage, supplying a protein supplement with additional nutrients will go a long way for her short and long-term performance.

“From days 0-90, the goal is to maintain body condition by avoiding under and over-nutrition.”

In an upland ewe, the target is a 2.5 body condition scoring (BCS), which requires 4.8-6.0 MJ/day to maintain with grass intake potential of 0.75kg dry matter (DM)/day.

Adverse weather conditions such as drought or excess moisture can decrease both DM intakes and protein availability, putting upland ewes at risk of losing up to 50% of body fat reserves over the winter.

Moving into mid-pregnancy (days 30-90), nutrient demand is greatest for rapid placental development. Failure to meet this will result in both short and long-term fertility issues, Rumenco said.

“Within these 60 days, the ewe will develop a new vital organ that has a final weight of around 1kg,” Bond said.

“The placenta is vital to foetal growth and development by delivering oxygen and nutrients – and cannot be compensated for later in pregnancy.”

If underdeveloped, Rumenco said, flocks are at greater risk for low birth weights, higher lamb mortality, poor lamb vigour, poor maternal behaviour and lower fertility in replacement lambs.