The rumen is a vital part of cattle’s digestive system as it acts as a fermentation chamber, packed with micro-organisms that break down feed into usable energy for the cow to produce milk. Maintaining an efficiently functioning population of micro-organisms is key to supporting rumen health and is an important and effective strategy for overall performance in cattle.
Therefore, when thinking about conditions that affect rumen health and the cow’s rumen micro-organisms, adopting a probiotic-like approach can help a cow to recover her digestive efficiency and get back to good milk production. Conditions where it can help to think this way are rumen acidosis and mycotoxins.
Rumen Acidosis
The optimum rumen pH ranges between 6.5 and 7.0. Rumen acidosis is a condition when the rumen pH becomes too acidic and drops below the pH required for the microbes to optimally break digested forage. It can be caused by sudden changes in diet, rapid ingestion of highly fermentable carbohydrates or a lack of fibre in the ration.
If the pH drop is very severe, this can result in large drops in rumen pH which can be fatal. However, more common is a Subacute Ruminal Acidosis (SARA) with signs of reduced feed intake and appetite, reduced rumination, loose manure, lower milk yield and low milk fat concentration.
Acidosis can be prevented with good nutrition management. Gradual ration changes and correct amounts of fibre being fed is crucial. However, as the pit of forage is often variable, these changes in rations can be difficult to control. Live yeasts and inactive yeast extracts are particularly good at maintaining the rumen microflora to help buffer the lactic acid levels in the rumen. This reduces the duration and extent of the pH drop, improving feed intakes and helping maintain production.
Mycotoxins
Mycotoxins are naturally occurring toxic compounds produced by certain species of moulds and can be found in wet or mouldy feed or dry forages and can pose significant health risks to cattle. Cattle are generally quite resistant to mycotoxins however, cows with SARA are more susceptible to the effects of mycotoxins, as this lower rumen pH can impair the rumen’s natural detoxifying ability.
Mycotoxins exert their effects through reducing intakes, reducing nutrient absorption, altering hormone production and suppressing the immune system. This results in decreased milk production and an increase in other conditions such as mastitis, lameness, poor fertility and in severe cases, abortions.
To prevent the effects of mycotoxins, reducing the mycotoxin load is important. Making good quality dry forage which is well fermented, covered well with good quality sheeting/cling seal and managing the pit face well, all prevents moulds growing and mycotoxins being formed. These maximise the fermentation process and minimise secondary spoilage/heating. Additives from Magniva will help control the fermentation, particularly on high dry matter forages, reducing the presence of undesirable yeasts and moulds.
However, as the weather conditions are outside our control, the use of a mycotoxin binder or deactivator is important to reduce the impact of mycotoxins in the feed. Yeast cell wall extracts bind to mycotoxins, help their clearance from the body, reduce the effects of mycotoxins and improve gut health. These products can be easily incorporated into the feed, practically reducing the mycotoxin risk.
Summary
Ensuring optimum rumen health is essential for maximising milk production in cattle. The challenges posed by rumen acidosis and mycotoxins, can be reduced by strategies that enhance a balanced and resilient rumen microbial population. The use of live yeasts and yeast cell wall extracts maintain rumen pH, enhance microbial function and mitigate the effects of mycotoxins. Through good nutritional management and the incorporation of yeasts and yeast extracts into cattle feed, this can support the cow’s digestive efficiency, improve overall herd health and enhance milk yields.
