Ewe feeding in mid-pregnancy is often seen as less important than feeding immediately pre-and post-lambing, however, feeding in months two and three of pregnancy can have a huge bearing on lamb numbers and vitality.
EWE feeding in mid-pregnancy is often seen as less important than feeding immediately pre-and post lambing, however, feeding in months two and three of pregnancy can have a huge bearing on lamb numbers and vitality.
Laura Drury, ruminant technical adviser with Trouw Nutrition GB, says while the future of the British sheep industry remains uncertain, producers should be taking every opportunity to maximise lamb outputs to improve gross margins.
She says: “The mid-pregnancy period is critical for ensuring the production of strong, viable lambs to improve margins.”
She explains there are two key objectives at this stage: the first is to manage ewe condition by feeding to achieve the target lambing body condition score (BCS) of 3.0-3.5 for lowland ewes and 2.5 for hill ewes by eight weeks pre-lambing.
Ms Drury says: “You need to avoid weight loss in thin ewes, those with a BCS less than 2.0, while encouraging weight loss in overfat ewes [those with a BCS greater than 4.0] which will have a lower dry matter intake during late pregnancy, leading to increased fat mobilisation and a higher susceptibility to twin lamb disease.
For ewe lambs you should be aiming to increase body weight by 5 per cent in months two to three of pregnancy.”
The second key objective is ensuring optimal development of the placenta to support lamb growth.
Ms Drury explains that as it supplies all the nutrients to growing lambs, placental development is important for optimal lamb birth weights and survival. Poor placental growth can have a detrimental effect on lamb birth weight, increasing susceptibility to hypothermia, reducing colostrum intake leading to poor growth rates and lower survival.
“Mid-pregnancy is a vital phase for the placenta. If placental growth is compromised during this period, it cannot be compensated for in late pregnancy and may result in smaller, weaker and less viable lambs which will require more feed for growth and take longer to finish. This will reduce the opportunity to finish lambs earlier when prices are higher.”
She says a metabolisable energy intake of 10MJ/day with 85g/day of metabolisable protein is sufficient to meet the maintenance requirements of a 70kg ewe, which can usually be supplied from average quality grazing if a dry matter intake of 1kg/day is achieved, but she advises allowing a 30 per cent greater grazing allowance for thin ewes.
“Preliminary data from the AHDB sheep key performance indicator project indicates improvements in scanning percentages when ewes continue to gain condition through to scanning, so a small increase in nutritional supply over maintenance should be considered and factored into grazing allowances over winter.”
How to meet the needs of mid-pregancy ewes
LAURA Drury advises providing supplementary minerals at grass for optimal ewe health and performance as Trouw’s five-year average forage mineral analysis shows levels of zinc, cobalt, iodine and selenium in fresh grass are inadequate to meet requirements of ewes throughout mid-pregnancy.
“We would also advise all sheep producers to scan ewes at about 60-days pregnant as it has many benefits. Early detection of empty ewes will allow them to be removed from the in-lamb group saving on feed costs, while pregnant ewes can be grouped and fed according to the number of lambs being carried and body condition score.
“The mid-pregnancy period is a good time to plan ahead for the pre-lambing phase. Get forages analysed for nutritional and mineral content and select the appropriate pre-lambing supplements to balance forage in the run up to lambing.”