Farm Table says:
What is the problem?
Many farmers turn ewes out onto lambing paddocks at the start of lambing. The New Zealand research aimed to determine the impact of BCS (Body Condition Score) and herbage treatments during late pregnancy and lactation to understand the potential interaction on performance of twin-bearing ewes and their lambs.
What did the research involve?
- Massey University Farm, 5km south of Palmerston North
- Day 142 of pregnancy
- Twin bearing ewes
- BCS of 2.0, 2.5 or 3.0
- Allocated to ‘moderate’ (1,200kg – 1,300kg DM/ha) or ‘unrestricted’ (1,500kg – 1,800 kg DM/ha) nutritional treatment until Day 95 of lactation/weaning
What were the key findings?
- Nutritional treatments had no effect on lamb birth or weaning weight
- No benefit to lamb production of offering ewes >1,200 kg DM/Ha during very late pregnancy and lactation.
- “Lambs born to ewes in the Moderate treatment had a greater rate of survival than those born to ewes in the Unrestricted treatment. The cause for this greater rate of survival is unclear and unexpected.”
- “Ewes in the Unrestricted nutritional treatment had a greater BCS and back-fat depth at weaning than those in the Moderate nutritional treatment.”
Research concluded that ewes should aim to have ewes with a BCS of 2.5 or 3 in late pregnancy.