Ruminal Acidosis in Beef Cattle: The Current Microbiological and Nutritional Outlook

Ruminal pH over a 48-h period of a steer adapted to a 92.5% concentrate diet based on dry-rolled corn fed once daily at 0 and 24h. Ruminal pH was monitored with a submersible pH electrode suspended through the plug of the ruminal cannula and was recorded every minute (data from Cooper et al., 1998).

Total organic acid concentrations (●) and molar proportions of total VFA (■) and lactic acid (▴) in A) acute acidosis (data from Nagaraja et al., 1985) and B) subacute acidosis (data from Goad et al., 1998).

Amylolytic, maltose-fermenting, glucose-fermenting, and lactic acid-fermenting bacteria involved in starch fermentation to lactic acid and VFA in the rumens of grain-fed cattle.

Ruminal ciliated protozoal population (■) and ruminal pH (●) in cattle with experimentally induced acute acidosis (A; data from Nagaraja and Towne, 1990) and subacute acidosis (B; data from Goad et al., 1998).

Distribution of numbers of ruminal ciliated protozoa in feedlot cattle. Ruminal samples were collected at slaughter from 364 cattle fed different finishing diets (data from Towne et al., 1990b).