TY - JOUR
T1 - Influence of grain and monensin supplementation on ruminal fermentation, intake, digesta kinetics and incidence and severity of frothy bloat in steers grazing winter wheat pastures.
AU - Branine, M. E.
AU - Galyean, M. L.
PY - 1990/4
Y1 - 1990/4
N2 - Three 10-d collection periods (April 4 to 14, early April, EApr; April 23 to May 3, late April, LApr; May 10 to 20, 1984, mid-May, MMay) were conducted to evaluate effects of no supplement (C), .5 kg-head-1.d-1 (as-fed basis) supplemental grain (steam-flaked milo, G) or G plus 170 mg monensin.head-1.d-1 (M) on forage intake and digestion by 12 ruminally cannulated beef steers (four/treatment; avg initially BW = 393 kg) grazing irrigated winter wheat pasture. Ruminal pH was greater (P less than .01) for M than for C or G during EApr but was not altered by treatments in LApr or MMay. Compared with C, ruminal NH3 was decreased (P less than .10) by G and M (5 h after supplementation) in EApr, decreased (P less than .05) by G (2h) and increased (P less than .05) by M (8 h) in LApr and decreased (P less than .10) by G (-1h) in MMay. Treatments had little influence on total VFA concentrations or on molar proportions of acetate and propionate. Butyrate molar proportion was decreased (P less than .10) by M during EApr and LApr, but not during MMay. Monensin increased (P less than .05) fluid passage rate compared with C and G in EApr but not in other periods, Particulate passage measurements did not differ (P greater than .10) among treatments within periods. Forage DM intake was not influenced (P greater than .10) by supplementation during any period. Extent of in situ forage DM disappearance was greater (P less than .10) for M than for C or G during EApr (12 and 30 h of incubation) but was not different (P greater than .10) in LApr or MMay. Incidence of frothy bloat was decreased (P less than .05) by M during EApr; this reduction may have been related to effects of M on ruminal pH, forage digestion and fluid passage.
AB - Three 10-d collection periods (April 4 to 14, early April, EApr; April 23 to May 3, late April, LApr; May 10 to 20, 1984, mid-May, MMay) were conducted to evaluate effects of no supplement (C), .5 kg-head-1.d-1 (as-fed basis) supplemental grain (steam-flaked milo, G) or G plus 170 mg monensin.head-1.d-1 (M) on forage intake and digestion by 12 ruminally cannulated beef steers (four/treatment; avg initially BW = 393 kg) grazing irrigated winter wheat pasture. Ruminal pH was greater (P less than .01) for M than for C or G during EApr but was not altered by treatments in LApr or MMay. Compared with C, ruminal NH3 was decreased (P less than .10) by G and M (5 h after supplementation) in EApr, decreased (P less than .05) by G (2h) and increased (P less than .05) by M (8 h) in LApr and decreased (P less than .10) by G (-1h) in MMay. Treatments had little influence on total VFA concentrations or on molar proportions of acetate and propionate. Butyrate molar proportion was decreased (P less than .10) by M during EApr and LApr, but not during MMay. Monensin increased (P less than .05) fluid passage rate compared with C and G in EApr but not in other periods, Particulate passage measurements did not differ (P greater than .10) among treatments within periods. Forage DM intake was not influenced (P greater than .10) by supplementation during any period. Extent of in situ forage DM disappearance was greater (P less than .10) for M than for C or G during EApr (12 and 30 h of incubation) but was not different (P greater than .10) in LApr or MMay. Incidence of frothy bloat was decreased (P less than .05) by M during EApr; this reduction may have been related to effects of M on ruminal pH, forage digestion and fluid passage.
UR - http://www.scopus.com/inward/record.url?scp=0025411016&partnerID=8YFLogxK
U2 - 10.2527/1990.6841139x
DO - 10.2527/1990.6841139x
M3 - Article
C2 - 2332388
AN - SCOPUS:0025411016
SN - 0021-8812
VL - 68
SP - 1139
EP - 1150
JO - Journal of animal science
JF - Journal of animal science
IS - 4
ER -