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 can also play an important role in influencing cow health and production during times of heat stress.
Diets high in fibre result in higher heat production from digestion, so where possible providing lower fibre crops or supplements will help reduce the heat stress experienced by the cow. Adding Levucell®SC live yeast to the diet during heat stress conditions is also beneficial as it has been shown to improve fibre digestibility1 and reduce the impact of heat stress on dairy cow performance2. A trial conducted at the University of Florida showed a 45% reduction in the number of cows at risk of heat-stress induced rumen acidosis and a 2% improvement in feed conversion efficiency in Holstein cows that were fed Levucell®SC during heat stress conditions.
Warm humid conditions are also 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 mycotoxins3. Fusion® DYAD is a broad spectrum binder which binds certain mycotoxins including aflatoxin, ergot alkaloids, zearalenone and fumonisins.
Lastly, increased metabolic activity during heat stress increases oxidative stress in the cow4. This means that during heat stress conditions it is beneficial to increase both primary and secondary antioxidants. Therefore, 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.
Contact your PGW Technical Field Representative to arrange a nutrition consultation with your local Nutritech Area Manager and Nutritionists.
- Chaucheyras-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
- Marsola et al., (2010). Effect of feeding live yeast on performance of Holstein cows during summer. Journal of Animal Science, 88
- Fusion®DYAD is a registered pursuant to the ACVM Act 1997 No.A011062.
- Turk,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
This article was originally published in the Rural Diary in November 2020.