Monensin level during grain adaptation and finishing performance in cattle.
Two finishing trials were conducted to measure the response of cattle adjusting to high-concentrate diets to dietary monensin level. In trial 1, 54 individually fed Hereford-Angus steers (312 kg), previously fed a two-thirds corn silage: one-third corncob-based diet, were allotted in a 2 X 3 factorial arrangement of treatment with tylosin (0, 11 mg/kg) and monesin (0, 11, 33 mg/kg) fed during a 28-d, grain-adaptation period (fed 75% concentrate for 6 d and then fed 95% concentrate). After 28 d, all steers were continued on their respective levels of tylosin and 33 mg/kg monensin for the remaining 119 d. Daily intake patterns indicated digestive upset in all treatments during adjustment to the 95%-concentrate diet. Blood samples taken during the first 28 d revealed no differences in acid-base status in response to monensin level; however, all steers exhibited reduced (P less than .01) pH and HCO3 and increased (P less than .01) lactate after 4 d on a 75%-concentrate diet. In the initial 28 d, intake decreased (linear P less than .05) as the level of monensin increased. In the total finishing period, however, increasing the level of monensin fed during grain adaptation decreased (linear P less than .05) intake and tended to decrease (linear P = .20) gain with no effect on feed efficiency.(ABSTRACT TRUNCATED AT 250 WORDS)
Burrin
D G
DG
Dept. of Anim. Sci., University of Nebraska, Lincoln 68583-0908.
Stock
R A
RA
Britton
R A
RA
D000138:Acidosis / Q000517:prevention & control / Q000662:veterinary; D000222:Adaptation, Physiological; D000821:Animal Feed; D000818:Animals; D001835:Body Weight / Q000187:drug effects*; D002417:Cattle / Q000254:growth & development*; D002523:Edible Grain; D007933:Leucomycins / Q000494:pharmacology; D008297:Male; D008985:Monensin / Q000494:pharmacology*
D007933:Leucomycins; D008985:Monensin