Carregcynffyrdd Project Final Update : October 2025
Key results:
- The treated group scanned at 166%, while the untreated group scanned higher at 173%. This indicates that the propylene glycol treatment, as administered, was ineffective.
- By replacing part of the diet with barley, Carregcynffyrdd reduced feeding costs by £0.06 per ewe per day, saving a 200 flock of twin bearing ewes a total of £168 over a two week period.
Background:
Carregcynffyrdd, is farmed by Carys Jones and family where they run a flock of 400 Llanymddyfri Welsh ewes and 100 Romney cross ewes, alongside a herd of 50 suckler cows.
Over recent years, Carys has strived to improve on-farm efficiencies through adapting the breeds used at Carregcynffyrdd and performance recording. Carys was keen to take the opportunity to investigate cost-effective management of feeding ewes at the same time as maximising flock outputs – key factors that will resonate with many other Welsh farmers in similar circumstances.
The project aimed to, where possible, maximise the use of sustainable, locally produced protein sources and minimise the use of expensive feed ingredients and imported protein
Purpose of the work
- Develop a cost-effective diet for the flock through the year;
- Reduce the reliance on imported feed ingredients;
- Trial pre-tupping dosing of propylene glycol to half the flock to measure whether this had an effect on lamb numbers at scanning.
What we did:
The ewes body condition scores were monitored and an ewe feeding plan was created, ensuring a good value diet that delivered sufficient energy for the last 8 weeks of pregnancy and sufficient protein for the last 2-3 weeks of pregnancy for lambing 2024.
A separate trial was also set up ahead of tupping in 2024 where a group of ewes were weighed and body condition scored and every odd number tagged animal was dosed with 25ml of propylene glycol to see whether administering the propylene glycol had an effect on lamb numbers at scanning.
Outcomes:
Flock diet plan
For pregnant ewes at Carregcynffyrdd, Carys worked with Fiona Lovatt of Flock Health to draw up a new feeding strategy to optimise ewe nutrition and reduce costs. Analysis of the baled silage showed good levels of protein but low fermentable energy. To address this, barley was used to supplement with a reduced amount of concentrates. This approach significantly lowered feed costs, with barley costing £158/t compared to £365/t for concentrates in 2024. In the final two weeks of pregnancy, twin-bearing ewes were fed 500g of concentrate and 300g of barley daily, along with ad-lib silage. This tailored ration demonstrates how adjusting feed based on forage quality and ewe needs (based on condition, size and lamb litter size) can maintain nutritional standards while cutting costs.
Propylene glycol trial
Following treating a sample group of sheep (average body condition score of 3.2 at time of treatment) with propylene glycol at Carregcynffyrdd, the pregnancy scan rate did not show an improvement as a result. The treated group scanned at 166%, while the untreated group scanned higher at 173%. However, this difference was not statistically significant (p=0.1). This indicates that the treatment, as administered, was ineffective.
Other studies have found a positive effect of using propylene glycol to increase ovulation rates by providing an energy boost that helps support the physiological processes leading up to ovulation. However, this effect is believed to be short lived, lasting around 12 hours. Therefore it is likely to have a more positive result on synchronised ewes.
How to apply on your farm:
- Analyse silage for energy and protein levels so cost effective rations can be formulated and sourced before the final eight weeks of pregnancy.
- Body condition score your ewes to monitor condition throughout the year so that adjustments can be made to avoid a drop in performance. It takes on average 6-8 weeks on a good quality diet to improve a BCS by one unit.
- Consider ewe energy needs at different times of year, based on their condition, size and lamb litter size.
- Support is available to develop ewe nutrition plans through the Farming Connect Advisory Service, contact your local development officer for further information.