Location: Food and Feed Safety Research
Title: Grazing activity and ruminal bacterial population associated with frothy bloat in steers grazing winter wheat Authors
Submitted to: Professional Animal Scientist
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 28, 2012
Publication Date: April 5, 2013
Citation: Min, B.R., Pinchak, W.E., Hernandez Jr, C.A., Hume, M.E. 2013. Grazing activity and ruminal bacterial population associated with frothy bloat in steers grazing winter wheat. Professional Animal Scientist. 29:179-187. Interpretive Summary: Two experiments were designed to determine shifts in stomach bacteria populations in cattle fed wheat or grass and either suffering or not suffering from gas bloat disease. Three stomach bacteria were found in high numbers in cattle fed grass and not suffering from bloat disease. Six other stomach bacteria were found in high numbers in cattle fed wheat and suffering from gas bloat, indicating that gas bloat disease may be associated with these specific bacteria. Total time not feeding was greater for cattle suffering gas bloat disease than for cattle not suffering gas bloat disease. The results indicate changes in stomach bacteria and feeding time when steers experienced gas bloat disease. The results suggest that gas bloat disease in cattle may be affected by diet, which in turn affects the types of stomach bacteria present. These results are of interest to beef cattle producers and researchers.
Technical Abstract: Two grazing experiments were designed to elucidate the shifts in rumen bacterial populations (Exp. 1) and grazing activities (Exp. 2) in wheat forage diets between bloated and non-bloated steers. In Exp. 1, the bacterial DNA density was greatest for Ruminococcus flavefaciens, Streptococcus bovis, and Eubacterium ruminantium among tested strains when steers fed bermudagrass hay (d 0). Steers that grazed wheat forage, however, increased the bacterial density of 6 major rumen bacterial populations in bloated steers, indicating that frothy bloat may be associated with a species-specific bacterial population. In Exp. 2, overall time, total grazing, and ruminating time did not differ between bloated and non-bloated steers. In contrast, idling time was greater for bloated (P < 0.01) than for non-bloated steers (10.9 vs. 7.9 h/d, respectively). Bloated steers did not differ in total grazing activity patterns; however, grazing activity in bloated steers decreased (P < 0.05) between 0400 to 0700 h and 1400 to 1800 h. Ruminating activity in non-bloated steers peaked between 0200 to 0500 h and 1900 to 2200 h, but was lower (P < 0.05) for bloated than for non-bloated between 0100 to 0600 h and 0700 to 1200 h. The data suggest that rumen bacterial populations and grazing activities changed when steers experienced frothy bloat.