Managing animal health in clover/rye-grass and multispecies swards

Multispecies swards and clover-rich pastures offer highly nutritious grazing, but they also bring health risks like bloat, fertility issues, mineral imbalances and parasite pressure. Learn how to manage those risks effectively.

Manage animal health through monitoring livestock closely, especially after pasture changes. Along with good grazing, records of inputs and health issues can help to spot trends early and prevent problems further down the line.

Bloat is caused by rapid fermentation in the rumen, particularly when livestock graze lush white clover with high protein and moisture content.

Risk is highest during rapid growth phases, especially in wet and humid conditions.

Signs of bloat include a swollen left flank, restlessness or reduced appetite.

Act fast and remove animals, treating them with anti-bloat medication or a stomach tube. Seek vet help if symptoms persist.

How to reduce the risk:

• Balance your sward: Include grasses (e.g. rye-grass) and herbs to dilute clover content and slow fermentation
• Introduce gradually: Let livestock adjust to clover-rich pastures to avoid sudden dietary shocks
• Feed hay or straw first: A fibre source before grazing reduces overconsumption of lush clover
• Use anti-bloat supplements: Blocks or drenches with poloxalene are effective during high-risk periods

Time your grazing: Avoid grazing wet pastures in the early morning. Rotate regularly to prevent overgrazing of clover hotspots.

Some clovers (especially red) contain natural compounds that can disrupt fertility in breeding animals.

Avoid grazing high-clover swards during tupping/mating and use mixed swards to dilute effects.

Multispecies swards can be lower in key trace elements like selenium, cobalt and copper, especially when grass content is low. Ensure you test soils regularly and adjust fertiliser plans accordingly.

Provide mineral buckets or boluses, particularly for breeding animals and youngstock.

Rotational grazing helps reduce worm burdens, but multispecies swards can still harbour parasites:

• Use faecal egg counts to monitor burdens and avoid blanket worming
• Rotate pastures effectively to break parasite life cycles
• Worm only when needed, based on vet advice and test results

Wet ground and dense swards can lead to hoof problems. Provide dry areas for lying, especially in wet weather. Trim feet regularly, particularly in longer grazing seasons, and avoid poaching, especially in wetter fields.

Clover-rich swards are protein-dense but low in fibre, which can cause digestive upsets. Balance the diet with hay or straw to support rumen health and use fibre-based supplements during periods of rapid clover growth or low grass availability.

Diverse swards can occasionally include harmful species, so walk your pastures regularly and remove any poisonous plants. Defra and vet bodies offer useful ID guides.

If in doubt, seek vet advice – early action can prevent bigger problems.