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Two experiments were conducted to investigate the effects of proportion of dietary corn silage during periods of feed restriction on performance of steers. In Exp. 1, Simmental x Angus steer calves (n = 107; initial BW = 273 [+ or -] 3.8 kg) were allotted to 12 pens with eight or nine steers/pen and four pens/treatment. Periods of growth were 273 to 366 kg BW (Period 1), 367 to 501 kg BW (Period 2), and 502 to 564 kg BW (Period 3). In two of the dietary regimens, steers were given ad libitum access to feed throughout the experiment and were fed either a 15% corn silage diet in each period or an 85, 50, and 15% corn silage diet in Periods 1, 2, and 3; respectively. In the third feeding regimen, a programmed intake feeding regimen was used. Steers were fed a 15% corn silage diet in each period. However, feed intake was restricted to achieve a predicted gain of 1.13 kg/d in Period 1 and 1.36 kg/d in Period 2, and feed was offered for ad libitum consumption in Period 3. For the entire experiment, ADG was similar (P = 0.41) among treatments and feed efficiency was lower (P [is less than] 0.10) for steers in the corn silage regimen than for steers in the programmed intake and ad libitum regimens. In Exp. 2, Simmental x Angus steer calves (n = 106; initial BW = 233 [+ or -] 2 kg) were allotted by BW to 12 pens (three pens/treatment) and fed in three periods similar to those described in Exp. 1. Four feeding regimens were investigated: 1) AL; steers were offered a 15% corn silage diet for ad libitum consumption in all three periods; 2)PI; DMI was programmed to achieve gains as described in Exp. 1; 3) CS-HLL; programmed intake as described above except diets contained 85, 15, and 15% corn silage in Periods 1, 2, and 3, respectively; and 4) CS-HIL; same feeding regimens as CS-HLL, except diets contained 85, 50, and 15% corn silage in Periods 1, 2, and 3, respectively. Steers were given ad libitum access to feed in Period 3. Overall ADG was lower (P [is less than] 0.05) for steers in the CS-HLL and CSHIL feeding regimens than for steers in the AL and PI regimens; feed efficiency was greatest for steers in the PI regimen. Few effects of feeding regimen on carcass characteristics were observed. Key Words: Corn Silage, Performance, Steers, Weight Gain

Two experiments were conducted to investigate a feeding regimen in which a programmed amount of feed was offered daily to control growth rate of steers. In Exp. 1, steers (n = 107, 309 [+or -] 3 kg) were used to determine effects of offering ad libitum access to feed (AL) vs a programmed intake feeding regimen (PI) and the number of days steers were fed (168 vs 203) on performance and carcass characteristics. Steers in the programmed intake feeding regimen were fed to achieve a predicted gain of 1.13 kg/d for the first 78 kg of gain, 1.36 kg/d for the next 124 kg of gain, and were given ad libitum access to feed for the final 54 or 103 kg of gain before slaughter (for steers fed for 168 d or 203 d, respectively). Feed efficiency was greater (P [is less than] 0.02) for steers in the PI than for those in the AL feeding regimen (0.193 vs 0.183 kg gain/kg feed, respectively). From d 169 to 203, steers in the PI feeding regimen had greater (P [is less than] 0.06) ADG (1.60 vs 1.38 kg/d) and similar (P = 0.38) feed efficiency than steers in the AL regimen. In Exp. 2, steers (n = 96; 308 [+ or -] 3 kg BW) were offered feed ad libitum throughout the experiment (AL) or were programmed to gain at a high (PI-H) or low (PI-L) growth rate. For the first 78 kg of gain, intake was restricted to achieve predicted gains of 1.13 kg/d (PI-L) or 1.25 kg/d (PI-H). For the next 124 kg of gain, intake was restricted to achieve predicted gains of 1.36 kg/d (PI-L) or 1.47 kg/d (PI-H). Feed was offered ad libitum for the final 58 kg of gain. Overall ADG was similar (P [is greater than] 0.37) among feeding regimens despite lower DMI for the steers in the PI-L and PI-H feeding regimens than for those in the AL regimen. Feeding regimen did not affect (P [is less than] 0.22) carcass characteristics. Programmed intake feeding regimens sustained growth rate and feed efficiency for an extended period of time without detrimental effects on carcass characteristics. Key Words: Feedlots, Finishing, Performance, Steers, Weight Gain

One hundred forty-three Angus x Simmental crossbred steers (initial BW = 155.1 [+ or -] 4.5 kg) were used in a 2-yr study (yr 1, n = 67; yr 2, n = 76) to determine the effects of weaning age, implant regimen, and the weaning age x implant regimen interaction on steer growth and performance, organ mass, carcass characteristics, and cooked beef palatability. Steers were early-weaned at an average age of 108 d (EW) or normally weaned at an average age of 202 d (NW) and allotted by weight to an aggressive or nonaggressive implant regimen. On their respective weaning dates, EW and NW steers were penned individually and fed a grain-based diet until they were slaughtered at a final BW of 546 kg. A subsample of steers (n = 2 per treatment) were slaughtered at 254 kg. At 254 kg, EW steers implanted with the aggressive implant regimen had 64% greater backfat depth than those implanted with the nonaggressive implant regimen; converse]y, NW steers implanted with the aggressive implant regimen had 52% lower backfat depth than those implanted with the nonaggressive implant regimen (weaning status x implant regimen interaction; P [is less than] 0.01). A similar interaction was observed for empty visceral organ weights. Early-weaned steers were younger (354.7 vs 372.4 d; P [is less than] 0.01) at final slaughter but were in the feedlot longer (246.5 vs 169.6 d; P [is less than] 0.01) than NW steers, whereas the aggressive implant regimen decreased days fed (203.3 vs 212.7; P [is less than] 0.07) compared to the nonaggressive implant regimen. Overall ADG was greater for EW than for NW steers (1.61 vs 1.50 kg/d; P [is less than] 0.01) and for the aggressive compared with the nonaggressive implant regimen (1.59 vs 1.52 kg/d; P [is less than] 0.02). Early-weaned steers consumed less DM per day (7.4 vs 8.5 kg/d; P [is less than] 0.01) and were more efficient (0.217 vs 0.208 kg/kg; P [is less than] 0.02) but consumed more total DM (1,817 vs 1,429 kg; P [is less than] 0.01) than NW steers while in the feedlot. Implant regimen did not affect DMI (P [is greater than] 0.37) or feed efficiency (P [is greater than] 0.15). Weaning status did not affect carcass characteristics (P [is greater than] 0.14), final empty body composition (P [is greater than] 0.25), or final longissimus muscle composition (P [is greater than] 0.18); however, steaks from EW steers had higher (P [is less than] 0.05) taste panel tenderness and juiciness ratings than steaks from NW steers. The aggressive implant regimen decreased yield grade (P [is less than] 0.02), but did not affect quality grade (P [is greater than] 0.86) compared to the nonaggressive implant regimen. Placing early-weaned steers on an aggressive implant regimen is a viable management option. Key Words: Beef Cattle, Growth Promoters, Weaning

Two experiments were conducted to determine supplemental CP requirements for feedlot steers prescription-fed to achieve stepwise increases in ADG during the feeding period. In Exp. 1, 106 steers (initial BW = 285.7 [+ or -] 3.4 kg) were allotted to 12 pens. Treatments consisted of ad libitum consumption of a 12% CP diet throughout the experiment (AL12%), prescription intake of a 12% CP diet (PI12%), or prescription intake of high-CP diets (PIHCP). The PIHCP diets were formulated to provide the same grams of CP per day as the AL12% diet. Steers in the prescription intake feeding regimens were fed to gain 1.13 kg/d for the first 87 kg of gain and 1.36 kg/d for the next 134 kg of gain and were offered feed for ad libitum consumption for the final 52 kg of gain before slaughter at 559 kg. Overall ADG was lower (P [is less than] 0.05) for steers fed PI12% and PIHCP diets than for those fed the AL12% diet (1.48 and 1.50 vs 1.60 kg/d, respectively). Total DM intake was lower (P [is less than] 0.08) for steers fed the PI12% and PIHCP diets than for steers fed the AL12% diet (1,359, 1,370, and 1,421 kg, respectively). Dressing percentage, back-fat thickness, and quality grade were lower (P [is less than] 0.05) for steers fed the PI12% and PIHCP diets than for steers fed the AL12% diet. In Exp. 2, 142 steers (initial BW = 285.4 [+ or -] 3.1 kg) were allotted to 16 pens. System 1 was ad libitum consumption of a 12% CP diet throughout the experiment. Steers in Systems 2, 3, 4, and 5 were subjected to the same prescription intake strategy as steers in Exp. 1. During the three phases of growth (1.13 kg/d, 1.36 kg/d, and ad libitum), steers were fed the following CP concentrations: System 2(12, 14, and 12%); System 3(12, 14, and 14%); System 4(12, 16, and 12%); and System 5(12, 16, and 14%). No differences (P [is greater than] 0.06) in total steer performance, carcass characteristics, or carcass chemical composition were observed among systems. Increasing percentage of CP in diets of prescription-fed steers to provide the same daily intake of CP as steers consuming feed ad libitum was not beneficial. Key Words: Feed Intake, Feedlots, Protein, Steers

Targhee x Hampshire lambs (average BW 23 [+ or -] 1 kg) were used in two experiments to determine the effects of finishing on concentrate with an anabolic implant or forage grazing after concentrate feeding on growth, organ and viscera weights, and carcass tissue accretion. In Exp. 1 and 2 lambs were penned by sex and assigned for slaughter at initial (23 kg), intermediate (37 kg), or end BW (ewes, 47.7; wethers 50.4 kg). From 23 to 37 kg BW, lambs were fed all-concentrate diets in drylot (DL) or grazed on alfalfa (ALF). Experiment 1 was a 2 x 2 factorial with 28 lambs; factors were wether vs ewe lambs and unimplanted vs DL implanted with trenbolone acetate-estradiol benzoate. There were no differences in organ and viscera weights due to implant status. However, ADG (P [is less than] .03) and lean gain (P [is less than] .02) were greater for implanted than for unimplanted wethers (507 vs 357 g and 1,314 vs 656 g, respectively). Ewes did not respond to the implant. Fat accretion was not affected by implantation. Experiment 2 was a 2 x 3 factorial with 42 lambs; factors were wether vs ewe lambs and drylot during growing and finishing phases (DL-DL) vs drylot during growing and alfalfa grazing during finishing (DL-ALF) vs alfalfa grazing during growing and finishing phases (ALF-ALF). In Exp. 2, ADG of DL-DL lambs was greater (P [is less than] .01) than ADG of DL-ALF or ALF-ALF lambs. Lambs on ALF-ALF had smaller (P [is less than] .05) livers and rumen/ reticulum weights but heavier (P [is less than] .04) kidney, omasum, small and large intestine, and cecum weights than those on DL. In Exp. 2, DL-ALF and ALF-ALF lambs had overall hindsaddle lean gain equal to those on DL-DL with less mesenteric fat and 100 g less separable fat. Finishing lambs on alfalfa reduced fat accretion without decreasing lean accretion, whereas trenbolone acetate implants for lambs fed concentrate increased BW gain and lean accretion without affecting fat accretion. Key Words: Fat, Lambs, Lean, Performance, Viscera

Although small and mid-size cattle and sheep producers may be positioned to meet local market demand for grass-based meat and meat products, they share similar challenges as they consider converting to grass-based systems. A survey of Ohio beef and sheep producers reveals a number of underlying factors that influence the decision to convert a livestock management system to a grass-base including available infrastructure, knowledge and technical skills, financial costs and a desire to change their system. These findings demonstrate that there are substantive production and marketing issues that influence producer decisions to change an existing management system. A better understanding of the livestock production system and direct marketing opportunities can improve local food programs’ capacity to increase the supply of grass-based meat and meat products. [ABSTRACT FROM AUTHOR]