CAREFUL management of ewe nutrition to ensure a body condition score of 2.5-3.0, from pre-tupping right throughout the majority of pregnancy, is vital to ensure successful foetal growth and development.

According to Dr Michael Marsden, Trident Feeds technical manager, the ewe's additional requirements for energy and protein are relatively low, during the early stages of pregnancy, but they increase rapidly during the final six weeks as approximately 70% of foetal growth occurs during this period.

"It's crucial to remember that as lambs continue to grow in the uterus, they take up a greater proportion of body space, reducing the capacity of the ewe's rumen. And as a result, their appetite can decrease by up to 30%," said Dr Marsden.

"For this reason, it's important to increase the nutrient density of the ration as the gestation period progresses to keep the additional nutrient supply at equal pace with foetal growth.

"Farmers should be aiming for an energy content of at least 12.5MJ ME per kg DM in the supplementary concentrates, plus at least 16% to 18% crude protein if feeding hay or silage; or 20% for straw-based rations."

Dr Marsden believes that given this year's favourable cereal prices, farmers will be looking to feed as much cereal-based feed as possible. However, too much starch can quickly upset the rumen, causing acidosis. This, he said, can lead to lower birth weights and poor milk quality, ultimately affecting early lamb growth rates.

Instead, he advised farmers only to feed cereals provided this starchy energy is balanced adequately in the rumen. "This can be managed by including a good amount of digestible fibre, which is available from feed sources such as sugar beet feed and low-copper, typically 32% protein bioethanol distillers' feeds such as British wheat distillers from Trident Feeds," says Dr Marsden.

"Both feed sources have a slower rate of rumen fermentation, when compared to cereals, so the risk of digestive upsets is reduced. The feed sources can also stimulate dry matter intake and provide more nutrients for milk production."

Dr Marsden believes that British wheat distillers represent an exciting addition to the ruminant feed industry.

"They're domestically-produced at the Vivergo biorefinery in Yorkshire, and unlike the majority of wheat distillers from the whisky distillery process that use copper stills, the pellets or meal can be fed to sheep, because of the low copper content. This is a key consideration for farmers, especially with some breeds, where copper is particularly dangerous."

He added that these feeds are ideal for supplementing ewes as they also offer the high energy required during the late stages of gestation.