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Providing nutritional support for cows during heat stress conditions

Providing nutritional support for cows during heat stress conditions

Providing nutritional support for cows during heat stress conditions

Heat stress can significantly impact cow health and production. It can lead to reduced feed intake, rumination rumen function, milk yield and milk fat and protein levels and increased respiration rate and risk of acidosis.

While many of us are aware of practical solutions for heat stress, such as providing shade, increasing access to water and reducing daily walking distance, nutrition also plays an important role.

Diets high in fibre result in higher heat production from digestion, so where possible providing lower fibre crops or supplements assists in reducing the heat stress experienced by a cow. Adding Levucell®SC live yeast to the diet during heat stress conditions is beneficial, as it has been shown to improve fibre digestibility’ and reduce the impact of heat stress on dairy cow performance². A trial conducted at the University of Florida showed a 45 percent reduction in the number of cows at risk of heat-stress induced rumen acidosis and a two percent improvement in feed conversion efficiency in Holstein cows that were fed Levucell®SC during heat stress conditions.

Warm humid conditions also pose a high risk for mycotoxins. Mycotoxins can cause liver damage, increased somatic cell count, reduced reproductive performance, lameness, aflatoxin M1 contamination of milk and general ill thrift. Fusion® DYAD is designed to minimise the negative effects of feed borne mycotoxins. It contains multiple ingredients to provide a broad spectrum binder of mycotoxins including alfatoxin, ergot alkaloids, zearalenone and fumonisins.

Lastly, increased metabolic activity during heat stress increases oxidative stress in the cow³. This means that during heat stress conditions it is beneficial to increase both primary and secondary antioxidants. The Nutritech Heat Stress pack contains Vitamin E, Alkosel® organic selenium and primary antioxidant enzyme Melofeed®, to provide a powerful antioxidant top up to your regular mineral nutrition.

For further advice on how to nutritionally support your dairy herd this summer, contact your local PGG Wrightson Technical Field Representative.


¹Chaucheyras-Durand, F.A et al., (2010). Effect of a live yeast, Saccharomyces cerevisiae I-1077 on in situ ruminal degradation of alfalfa hay and fiber-associated microbes. Journal of Dairy Science, 93, 145.
²Marsola et al., (2010). Effect of feeding live yeast on performance of Holstein cows during summer. Journal of Animal Science, 88.
³Turk,R. et al (2015). The Effect of Seasonal Thermal Stress on Lipid Mobilisation, Antioxidant Status and Reproductive Performance in Dairy Cows. Reproduction in Domestic Animals, 50, 4.