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Submitted to: Rangeland Ecology and Management
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 12/7/2007 Publication Date: 5/15/2008 Citation: Kronberg, S.L. 2008. Intake of Water Containing Condensed Tannin by Cattle and Sheep. Rangeland Ecol. Manage. 61(3):354-358. Interpretive Summary: Condensed tannins are found in many trees, shrubs and forbs, and condensed tannin extracts from several plants are commercially available at reasonable cost. Results from our research indicate that cattle and sheep will drink water with small amounts of condensed tannin in it. Therefore, it may be possible to accomplish several useful management improvements with grazing sheep and cattle by placing small amounts of condensed tannin in their drinking water. These include improving their nitrogen use efficiency and productivity and reducing their methane production, susceptibility to bloat and reproductive problems associated with excess intake of ruminally degradable protein. Technical Abstract: Condensed tannins are found in many trees, shrubs and forbs, and are generally considered problematic phytochemicals for ruminants. However, ingestion of small amounts of condensed tannin by sheep and cattle has been shown to produce a number of valuable outcomes. The primary objectives of the trials were to determine if sheep and cattle would drink water that contained small amounts of condensed tannin and the magnitude of individual variation in intake. Animals were penned (or pastured) individually, fed twice daily and had ad libitum access to one or two liquids. Liquid intake was measured daily. Sheep (n=4) in the first trial drank tannin solutions well and variation among individuals was somewhat higher than for tap water, but no animals drastically reduced fluid intake when tannin was in their water. These sheep ingested up to 2% of their daily feed (alfalfa pellets) intake in tannin. When offered tap water and tannin water over 13 days, sheep drank more tannin water than tap water on the last 4 days of the test (P = 0.01). In a second sheep trial (n=8), they appeared to have less tolerance for tannin solutions. Sheep that were adapted slowly to tannin solutions did not drink more or less of more concentrated tannin solutions (P = 0.33). Generally, they neither preferred nor avoided tannin solutions when they had tap water to drink (P > 0.11). Hereford steers (n=10) drank tannin solutions surprisingly well and at the highest concentration of tannin, ingested 2.3% of their daily feed intake in condensed tannin. Variation in liquid intake among individual steers was only slightly higher for the tannin solutions compared to that for tap water. Angus crossbred steers preferred water instead of tannin-water when offered both simultaneously (P < 0.001), but drank some tannin-water each day. Results from this study indicate that it may be possible to accomplish several useful things with grazing sheep and cattle by placing small amounts of condensed tannin in their drinking water. |
