How can metabolic acidification be limited?
Acidosis is a metabolic disorder that affects monogastric and ruminant animals. It is associated with energy-rich and rapidly fermentable rations, which tend to lower pH (in the rumen of ruminants and of the blood in monogastric animals) and reduce zootechnical performance. This phenomenon can be limited through the use of sodium bicarbonate.
Acidosis in cows
Acidosis is a very common disorder in dairy cows, particularly in its subclinical form, and occurs when ruminal pH falls below normal values (6-6.4). It is mainly caused by diet enrichment and the pursuit of increased productivity. Indeed, in order to increase milk production and performance, an energy-rich and highly fermentable diet is necessary to rapidly provide the body with the nutrients it requires for milk production. Under normal conditions, the bacterial flora of the rumen transforms the energy provided by the diet into volatile fatty acids, which are then absorbed by the ruminal papillae. To compensate for the acidification of the rumen caused by the production of fatty acids, the cow naturally produces a bicarbonate-based salivary buffer secretion. But with energy-rich and highly fermentable rations (use of concentrates), fatty acids are produced more rapidly than they are absorbed, which leads to acidification of the rumen. Furthermore, rations that are low in fiber do not sufficiently stimulate rumination and salivation, thus preventing the cow from naturally restoring normal ruminal pH. As a result, the cow develops acidosis.
How can subacidosis be detected when animals are put out to pasture?
- Reduction in fat content (FC) is the first warning signal.
- Cows limp and suffer from digital dermatitis.
- They drink urine (Pica behavior) in an attempt to buffer ruminal pH.
- There is a drop in milk production and FC.
- The manure is soft, yellowish and shows signs of incomplete digestion (undigested fibers).
Acidosis can be prevented by adjusting the animal's diet. Sodium bicarbonate makes it possible to buffer ruminal pH and ensure the safety of energy-rich rations.