During summer months, particularly in periods of drought or high temperatures, pasture growth often declines significantly. We are currently seeing some very warm dry spells. Last month we looked at how to manage this shortfall of water, but as we look at reduced grass quality we need to consider how to manage this. This reduction in forage availability and quality can compromise nutritional intake, impacting performance, fertility and overall animal health. Strategic supplementation and careful monitoring are key to mitigating production losses.
🌾 Understanding the Summer Forage Gap
As perennial grasses mature and rainfall declines:
- Dry matter (DM) yields drop, reducing intake potential.
- Metabolisable energy (ME) and crude protein (CP) levels decline.
- Fibre concentration increases (NDF and ADF), reducing digestibility and voluntary intake.
These changes can lead to an energy-protein imbalance in grazing diets, particularly in high-producing animals such as lactating cows and rapidly growing youngstock.
🔬 Nutritional Interventions: Key Components
- Energy and Protein Supplementation
- Use high-energy concentrates (e.g. rolled barley, maize meal) to maintain energy density.
- Supplement rumen-degradable and bypass protein (e.g. soya, rapeseed meal) depending on production stage.
- Rumen function can be supported by maintaining a proper fermentable energy-to-protein ratio.
Fibre Management
- Offer conserved forages (e.g. grass silage, hay) to maintain rumen fill and promote rumination.
- Monitor physically effective fibre (peNDF) to avoid sub-acute ruminal acidosis (SARA) when feeding higher levels of concentrates.
Minerals and Trace Elements
- Dry pasture is often deficient in macro and trace minerals (e.g. Mg, Cu, Zn, Se).
- Provide free-access mineral supplements or boluses tailored to forage analysis results.
Water Supply
- Cattle may consume 40–80 litres/day during hot periods.
- Ensure unrestricted access to clean, fresh water to support feed intake, thermoregulation, and metabolic function.
Supplementary Feeding Strategies
When pasture fails to meet nutritional requirements:
- Conserved forages: Use silage or hay as a basal diet; analyse for nutrient content.
- Compound feeds: Ensure formulations match energy, protein, and mineral requirements.
- Forage crops: Consider brassicas (e.g. forage rape, kale) or root crops (e.g. fodder beet) as alternative grazing resources.
- Rotational or strip grazing: Helps maintain pasture quality and promotes regrowth.
⚠️ Monitoring and Evaluation
- Regularly assess Body Condition Score (BCS); declining condition indicates an energy deficit. We are able to offer this service iF you are unsure of what to do. Or speak to the vets today about how this works.
- Monitor milk yield, growth rates, and fertility indicators for early signs of under nutrition.
- Where possible use forage and blood analysis to fine-tune rations.
Planning for Future Resilience
Review stocking density relative to pasture availability.
Implement forage budgeting to estimate feed needs across the grazing season.
Invest in drought-tolerant grass and legume species to improve resilience of pastures to climatic variability.
During periods of limited pasture growth understanding forage quality and cattle requirements is essential. By applying targeted supplementation and proactive management, producers can maintain performance, support rumen function, and avoid longer-term health or fertility issues. Please speak to the team today and we will be able to come and offer some advice to you to ensure the health of your herd.
