A better feed efficiency will drive sustainability

The global dairy sector has been under a magnifying glass for many years already regarding its effect on the environment, in particular its contribution to the overall emission of greenhouse gasses. At the same time, the dairy sector is a growing and important industry, contributing to supplying the increased volume of animal protein needed for the growing world population. While the dairy farming sector has already made some huge improvements over the last decades, reflected in higher milk production and better genetics, the sector has to do better to meet today’s and future sustainability goals regarding methane emission, animal health and economics. The key to all this is feed efficiency. An increased feed efficiency not only reduces the carbon footprint per kilogram of milk or meat produced, it also benefits the cow’s health and performance and the farmer’s profitability, all key components of sustainable ruminant production.

Increasing feed efficiency starts by using better feed and feeding techniques, taking into account the choice and quality of raw materials and by-products used. But this only makes sense if you have a healthy working rumen, the most important organ in the digestive system of a cow. The rumen contains a complex ecosystem composed of anaerobic bacteria, protozoa, fungi and archaea (the rumen microbiota). The rumen microbiota plays an essential role in the nutrient acquisition and utilization of ruminants, as they break down plant material, whilst providing metabolic energy to animals. Rumen microflora is therefore strongly linked with feed efficiency. In many high producing dairy cows, the rumen is constantly challenged and can therefore not always work at full capacity. This can be the result of environmental challenges (such as heat stress) or sudden changes in the feed ration in terms of fibre or energy content for example. These challenges change the rumen microbiota and can make digestion less efficient or even lead to rumen disorders such as sub-acute ruminal acidosis (SARA) or acidosis. Many dairy cows are high producing animals, meaning that the rumen is constantly challenged. For many dairy cows this means room for improvement for rumen health.

The use of targeted feed additives is an effective and proven way to contribute to a healthy rumen environment by modifying the rumen and its microbes in such a way that they are more efficient in digesting a typical dairy cow diet, full of high fibre material. An effective nutritional approach is the use of the yeast probiotic Actisaf® Sc 47. This yeast probiotic has been proven to be effective for improving efficiency in dairy cows and helps to improve rumen health and feed conversion efficiency, leading to better herd performance and improved overall stock condition. Actisaf® Sc 47 stabilizes the rumen microbiota by making the environment more reducing, which helps to increase the pH, which is likely to favor some beneficial bacterial communities. A study performed at the University of Nottingham’s Center for Dairy Science Innovation (2020) clearly showed the effects of Actisaf® Sc 47 on milk yield and milk components, compared to non-supplemented cows (Table 1).

The supplemented cows had significantly better productivity at the same dry matter intake (DMI) which is related to better feed efficiency. In addition, it has been shown that cows supplemented with Actisaf® Sc 47 had higher digestibility coefficients for dry matter, neutral-detergent fibre (NDF), and tended to have higher digestibility coefficient for nitrogen than control cows (Table 2).

Accelerating the adoption of existing best practices and technologies to further improve production efficiency can help reduce emission intensity and make ruminant farming more sustainable. The implementation of nutritional strategies, including the use of feed additives such as yeast probiotic, has been suggested as effective approaches. By optimising and stabilising the rumen microbiota, Actisaf® Sc 47 increases feed efficiency through improved digestibility of fibre, unlocking more energy from the same amount of feed without jeopardising fertility or cow health. It allows the dairy farmer to do more with less and avoid nutrients waste and to increase milk performance and animal health.