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Description:
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Two experiments were conducted at the Texas Tech University Burnett Center in New Deal , TX to examine the effects of a dietary sweetener (Sucram C -150 ; Prince Agri Products , Quincy , IL ) on health , performance and dietary preference of feedlot cattle . In Exp . 1 , two hundred steer and bull calves (British x Continental ; average BW = 190 .4 kg ) were shipped 1 ,588 km from an order buyer facility in West Point , MS . On arrival , cattle were weighed and processed and assigned randomly to one of two treatments (eight pens per treatment ) during a 60 -d receiving period : 1 ) Control (CON ) = a 65 % concentrate receiving diet ; or 2 ) Sucram C -150 (SUC ) = a 65 % concentrate receiving diet with 200 mg /kg (DM basis ) of Sucram C -150 artificial sweetener . Diets were changed to 75 % concentrate on d 29 to 56 . Following processing , cattle were moved to their assigned pens and fed their respective diets ad libitum once daily at 0800 . Cattle were observed daily for symptoms of bovine respiratory disease (BRD ) and treated as needed when their rectal temperature was > 39 .7oC . Feeding SUC did not affect overall (P > 0 .15 ) DMI at any time during the 60 -d study ; however , between d 29 to 56 there was a trend (P = 0 .10 ) for increased DMI by cattle consuming SUC (5 .71 vs . 6 .02 kg /d for CON and SUC , respectively ) . From d 0 to 28 and d 0 to 56 there was a trend (P = 0 .11 and 0 .12 , respectively ) for increased daily gain by steers fed SUC . Gain efficiency was not affected by treatment , except between d 0 to 28 of the study , when SUC increased gain efficiency (P = 0 .01 ) . No differences were detected (P > 0 .10 ) for overall morbidity (cattle treated at least once for BRD ) between the two treatments (59 .6 and 58 .0 % for CON and SUC , respectively ) ; however , feeding SUC decreased (P = 0 .02 ) the proportion of morbid animals requiring two antibiotic treatments (52 .6 and 41 .0 % for CON and SUC , respectively ) and tended (P = 0 .10 ) to decrease the proportion of cattle treated twice that needed additional treatments . During the finishing phase , 180 steers from the receiving period were assigned (nine pens per treatment ) to the following treatments : 1 ) CON receiving /CON finishing ; 2 ) CON receiving /SUC finishing ; 3 ) SUC receiving /CON finishing ; 4 ) SUC receiving /SUC finishing . Diets fed ad libitum once daily at 0800 were 82 % concentrate for the first 14 -d , and were then switched to a final 90 % concentrate diet for the remainder of the experiment . The SUC diets contained 200 mg /kg (DM Basis ) of Sucram C -150 . Receiving (R ) and finishing (F ) period main effect means and their interactions (R x F ) were analyzed . Over the entire F period , there was a tendency (P = 0 .12 ) for overall ADG (d 0 to end ; days on feed ranged from 154 to 203 ) to be increased by feeding SUC . This effect was , however , not dramatic , and carcass -adjusted gain did not differ among treatments . Daily DMI was affected by the R x F interaction (P ¡Ü 0 .09 ) for all periods of the finishing phase , except from d 0 to 28 . This interaction was the result of greater DMI by cattle fed SUC in both the R and F periods than by cattle in the other three treatment groups . Decreased DMI by cattle in the SUC receiving /CON finishing treatment also contributed to this interaction . Performance -based dietary NEm and NEg concentrations were computed from NRC (1996 ) equations and resulting values did not differ greatly : 2 .27 , 2 .28 , 2 .26 , and 2 .25 Mcal of NEm /kg of DM and 1 .58 , 1 .59 , 1 .57 , and 1 .56 Mcal of NEg /kg of DM , respectively for CON /CON , CON /SUC , SUC /CON , SUC /SUC treatments respectively . In general , changes in carcass characteristics were minor . Marbling score was increased (P = 0 .07 ) for cattle fed the control diet vs . those fed Sucram C -150 during the R period , although these slight changes did not significantly change quality grade distribution . An R x F interaction was detected for longissimus muscle (LM ) area (P = 0 .10 ) and USDA yield grade (P = 0 .09 ) , reflecting greater LM area and yield grade for CON /SUC vs . CON /CON and for SUC /CON vs . the SUC /SUC .
In Exp . 2 , 12 steers (British and Continental breeding ; average BW = 378 .6 kg ) were used in a simultaneously replicated 3 x 3 Latin square dietary preference test . Each Latin square consisted of three pens (two steers per pen ) and three time periods . Each of the three feeding periods of the Latin square consisted of a 5 -d adaptation period followed by a 5 -d data collection period , giving a total time for the experiment of 30 -d . Pens had 2 .4 m of linear bunk space with a wooden bunk divider affixed halfway along the bunk , providing 1 .2 m of linear bunk space on either side of the divider . Dietary treatments consisted of : 1 ) Control = a 77 .5 % concentrate diet delivered daily on both sides of the divider ; 2 ) Sucram = a 77 .5 % concentrate diet supplemented with 200 mg /kg DM of Sucram C -150 delivered daily on both sides of the bunk divider ; and 3 ) Choice = a 77 .5 % concentrate diet supplemented with or without 200 mg /kg DM of Sucram C -150 delivered daily on either side of the bunk divider . Daily delivery of the Sucram and Control diets in the Choice dietary treatment were alternated randomly between sides of the bunk divider to prevent positional bias . Differences in dietary preference between Control and Sucram C -150 were largely not significant (P = 0 .57 to 0 .96 ) except on d 1 to 2 when Control had greater preference (P = 0 .01 ) than Sucram or Choice ; this result was not expected , as no dietary choice was provided in these two treatments . A difference in dietary preference was detected on d 0 to 1 (P = 0 .01 ) and d 2 to 3 (P = 0 .02 ) for Control vs . Choice and Sucram vs . Choice comparisons , with cattle provided the Choice treatment consuming 0 .49 and 1 .72 kg of DM more of the Sucram C -150 diet than the Control diet , respectively . This effect , however , was not consistent across days and average DMI over the 5 -d period did not differ (P = 0 .81 ) between dietary treatments .
From the results of these two experiments , the addition of 200 mg /kg (DM Basis ) Sucram C -150 to the diet of newly received cattle tended to increase receiving period ADG and resulted in fewer repeat antibiotic treatments to recover from BRD . The feeding of Sucram C -150 during the finishing phase had limited effects on performance and carcass characteristics . Dietary preference was not consistently increased by addition of Sucram C -150 to the diet of yearling steers . |