Rumen acidosis is a serious condition by which there is a drastic decrease in the pH of the rumen in cattle. Rumen lactic acidosis develops in ruminants that have ingested large amounts of feed rich in carbohydrates. It results in the production of large quantities of Volatile fatty acids (VFA) and lactic acid, thereby decreasing the rumen pH to non-physiological levels.

Ruminants have diverse microorganisms in their rumen living together in symbiotic relationship with the host. When these animals are affected with acidosis, there is a change in the pH of the rumen, further leading to a change in the microorganisms present in the rumen.

Rumen fluid was collected  from a healthy cow and cow suspected of rumen acidosis. Rumen fluid from a healthy cow  whose pH was around 6.5 to 7 was taken and observed under foldscope.  Many protozoa (flagellates, ciliates etc) were observed moving around quickly.( video A, figure1b), Similarly the rumen fluid from a cow suspected of rumen acidosis was also observed under foldscope(video B). Since the pH falls below 6 in an acidosis case, the ability of the rumen protozoa to survive, decreases, (only smaller ciliates could be observed (figure 1a)

Video A: Rumen fluid from a healthy cow (real time)

Video B: Rumen fluid from a cow suspected of rumen acidosis

a. b.

Figure 1 (a) small ciliate in rumen acidosis case and (b) various protozoa in an healthy cow