SPRING SUMMER BONUS MAGAZINE 2026

on the farm, just like bacteria do most of the digestion in the rumen. Without them, nothing really happens. Bacteria are the most numerous and metabolically diverse, and can broadly be further subdivided into fibrolytic (cellulolytic) bacteria, amylolytic bacteria, proteolytic bacteria, and lipolytic bacteria. Each group has their own specialised roles: • Fibrolytic: Thrive at a pH of around 6,2 to 7,0 and break down cellulose and hemicellulose in forages. High rumen pH favours fibrolytic bacteria, promoting efficient fibre digestion. A lower rumen pH inhibits fibrolytic microbes and encourages the growth of starch- fermenting species. A consistent low pH reduces fibre digestion since the fibrolytic bacteria die off. This can lead to a microbial imbalance that can take days to recover. • Amylolytic bacteria: Responsible for starch and sugar degradation. When high concentrate diets are fed, these microbes can increase rapidly and can tolerate a lower pH. When the pH drops to 5,2 or lower, most bacteria become stressed while acid-producing bacteria dominate and thrive, leading to an increased risk of subacute ruminal acidosis (SARA) or even acute acidosis. • Proteolytic bacteria: Degrade proteins into peptides and ammonia. • Lipolytic bacteria: Break down and hydrolyze plant lipids. Just like a mixer wagon mixes the feed and ensures the animals get a balanced, evenly distributed ration, protozoa “hold onto” starch and slow fermentation in a similar way. Protozoa prefer a pH above 5,8 and can help moderate fermentation rates by consuming starch granules and preying on some bacteria. They make up a smaller portion of the ruminal microbiome. Anaerobic fungi help break down tough plant cell walls and are very important when high fibre, low energy forages are consumed. They can be seen as the hammer mill used on a farm. Fungi can’t handle sudden drops in the rumen pH and recover slowly after dietary changes. Archaea remove excess gas from the rumen. In cows, methane gas is energy lost by the animal, similar to fuel energy leaving through an exhaust pipe . Archaea are the microbes responsible for the conversion of hydrogen and carbon dioxide into methane. This helps to maintain proper ruminal fermentation by removing hydrogen produced from fibre digestion. Just like looking after your tools and machines on the farm, farmers can support and “look after” rumen health using simple, practical management strategies . Practical ways to keep your cows’ rumen running like a well-oiledmachine 1. Ensure a balanced ration and adequate effective fibre De Heus developed SynchroFos (SFOS), a formulation approach designed to optimise the rumen environment, promoting microbial growth and activity, and ultimately increasing the supply of rumen microbial bypass protein. The fermentation rates of raw materials were determined and applied in formulating a balanced ration that supplies optimal levels of protein and energy in the rumen, thereby enhancing microbial efficiency. Secondly, supplying sufficient physically effective fibre stimulates chewing and saliva production, which plays a vital role in maintaining a healthy rumen. Saliva acts as a natural buffer that helps keep rumen pH stable and prevents acidosis. 2. Provide continuous access to clean water Water intake is critical for rumen function and feed intake. A lack of water reduces saliva production, slows rumen activity, and disrupts fermentation, which quickly leads to a decline in Spring/Summer 2026 BONUS www.agribonus.co.za 108