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Red clover research: ‘No impact on ewe fertility'


Farmer-led research in England and Wales has suggested that grazing ewes on red clover may not adversely affect fertility.

Four sheep producers are working with ADAS in an Innovative Farmers field lab. Findings from their trials have suggested that grazing ewes on herbal leys which contain red clover may have a positive effect on pregnancy rates.

This is in contradiction to 50-year old research from Australia and New Zealand which found that fertility was adversely impacted when ewes were grazed exclusively on red clover due to its phytoestrogen content.

Afbeelding: Ewes in a line

The field results

The field lab project divided ewes into two groups on each farm. One group was grazed on grass leys with no red clover and the other on herbal leys including the legume. On average the ewes in the control group scanned at 170% while the ewes mated on swards containing red clover scanned at 181%.

Gillian Preece, sheep farmer and senior consultant at ADAS said: “We want to encourage a wider uptake and less fear across the industry, especially as it’s such a good plant for nitrogen fixing.” She explained that the positive result is likely to be due to the sheep eating a more diverse diet as the herbal leys contained a variety of other plants, which are good for nutrition.

The key take away

ForFarmers Forage Manager Mel Digger said the results from the project were encouraging for sheep farmers: “The benefits of including red clover in grazing swards are widely known for both soil health and animal nutrition."

“Many farmers say they do not see any adverse impacts of grazing sheep on leys including red clover, however official advice still remains to avoid feeding red clover to pregnant ewes six weeks either side of tupping.”

For more information

For more information on feeding your ewes pre-tupping or for advice on improving your flock's health and performance please contact your local manager or send us an online enquiry using the link below: 


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