Subsequent Finishing Performance Research Articles

PSVI-1 Backgrounding and finishing systems for cattle fed corn silages and corn grains differing in amylase expression

Abstract Amylase is a key enzyme involved in the hydrolysis of starch, which typically constitutes the predominant source of energy in feedlot cattle diets. Performance of cattle during the backgrounding phase can influence performance during the subsequent finishing phase. Our objective was to assess growth performance of backgrounding steers fed diets that contained combinations of corn silage (S) and steam-flaked corn (G) from hybrids with high amylase expression (Enogen corn; E; Syngenta Seeds, LLC) or common corn hybrid (C), as well as subsequent finishing performance, carcass characteristics, and liver abscess incidence when fed G produced from the same hybrids. Crossbred steers (n = 911; 306 ± 8 kg initial body weight) were assigned randomly to one of four backgrounding treatments with 12 replicates in a randomized complete block experiment using a factorial treatment arrangement. Factor 1 consisted of two corn silage hybrids (ES or CS), and factor 2 consisted of two SFC hybrids (EG or CG). In the subsequent finishing phase, animals were assigned to one of two treatments consisting of two grain hybrids (EG or CG) with 24 replicates per treatment. Backgrounding diets (dry basis) contained 20.1% flaked corn and 41.6% corn silage, and finishing diets contained 81.5% flaked corn with triticale silage as a common roughage source. There was no three-way interaction for measures of interest, and no differences among treatment combinations with respect to average daily gain (ADG) or incidence of abscessed livers (P > 0.10). Steers fed CG during the backgrounding phase ate more than steers fed EG (P = 0.04), thus leading to improved overall efficiency of steers fed EG in the backgrounding phase compared with their counterparts fed CG (P < 0.01; Table 1). Overall efficiency tended to be greater for cattle fed CG during the finishing phase (P = 0.06) compared with cattle fed EG during the finishing phase. There was a tendency for interaction between G fed in the backgrounding and G fed in the finishing phase for hot carcass weight (P = 0.07), such that steers fed the same hybrid in both phases had greater carcass weight compared with those fed different hybrids in the backgrounding and finishing phases. Type of grain fed in the backgrounding and finishing phases, but not silage, impacted overall system efficiency.

PSIV-A-11 Effects of Supplementing Extruded Dried Distillers' Grains Cubes to Stocker Cattle Grazing Introduced Pastures on Subsequent Feedlot Performance and Carcass Characteristics

Abstract This research evaluated the effects of supplementing extruded dried distillers’ grains (DDG) cubes to grazing steers on subsequent finishing performance and carcass characteristics. Steers (n = 140) grazed tall fescue (Festuca arundinacea)/bermudagrass (Cynodon dactylon) pastures from 14 April to 17 September 2020 with supplementation treatments (n = 3 pastures/treatment) that included: 1) Fertilized Control (FC), no supplementation on N fertilized pastures (112 kg N/ha); 2) Fertilized Supplement (FS), supplemented DDG cubes at 2.9 kg/d prorated for 3-d/wk feeding on N fertilized pastures; and 3) Supplement (S), supplemented DDG cubes at 0.75% of BW/d prorated for 5-d/wk feeding on unfertilized pastures. All animals were followed through the finishing phase in a commercial feedyard to investigate carryover effects on feedlot performance in 2 pens comingled across supplemental treatment. Carcass characteristics were evaluated via ultrasonography on d0 and d84 of finishing, and measurements were obtained at harvest. Feed DMI were segregated to individual animals according to Guiroy et al. (2001) and Tedeschi and Fox (2020b). Supplemented animals were heavier (P < 0.01) at feedlot entry than FC, but harvest BW did not differ (P = 0.23). However, S and FS required 37 fewer days on feed (P = 0.01) than FC. Supplementation on pasture reduced total feed required (P = 0.02) and feed costs (P = 0.01) relative to FC. Gains were greater (P = 0.02) for FC and FS than S from d0 to d84, but did not differ thereafter (P ≥ 0.15). At harvest, FC had the greatest dressing percent (P < 0.01) and lower yielding carcasses than FS (P = 0.01), but did not differ (P = 0.11) from S. Overall, extruded DDG cube supplementation during grazing did not negatively affect subsequent feedlot performance or carcass characteristics, but reduced the total feed required for finishing.

Effect of Ruminally-Protected Lysine Supplementation to Growing Cattle on Growth and Subsequent Finishing Performance

Objective: The objective of this study was to evaluate the effects of ruminally-protected lysine supplementation fed during the growing phase to cattle limit-fed a corn-based diet, and to evaluate the subsequent finishing performance.

Effects of Various Grazing Systems on Grazing and Subsequent Finishing Performance

A total of 240 mixed black yearling steers were used to compare grazing and subsequent finishing performance from pastures with ‘MaxQ’ tall fescue, a wheat-bermudagrass double-crop system, or a wheat-crabgrass double-crop system in 2010, 2011, 2012, 2013, 2014, and 2015. Daily gains of steers that grazed MaxQ fescue, wheatbermudagrass, or wheat-crabgrass were similar (P > 0.05) in 2010. The daily gains of steers that grazed wheat-bermudagrass or wheat-crabgrass were greater (P > 0.05) than those that grazed MaxQ fescue in 2011 and 2012. The daily gains of steers that grazed wheat-crabgrass were greater (P > 0.05) than those that grazed wheat-bermudagrass and similar (P > 0.05) to those that grazed MaxQ fescue in 2013. The daily gains of steers that grazed wheat-crabgrass were greater (P > 0.05) than those that grazed wheatbermudagrass or MaxQ fescue in 2014, and daily gains of steers that grazed wheatcrabgrass were greater (P > 0.05) than those that grazed wheat-bermudagrass or MaxQ fescue and daily gain from wheat-bermudagrass was greater (P > 0.05) than those that grazed MaxQ fescue in 2015. Finishing gains were similar (P > 0.05) among forage systems in 2010, 2012, 2013, and 2014. Finishing gains of steers that grazed MaxQ fescue were greater (P < 0.05) than those that grazed wheat-bermudagrass in 2011 and greater (P < 0.05) than those that grazed wheat-bermudagrass or wheat-crabgrass in 2015.

Effect of bovine respiratory disease during the receiving period on steer finishing performance, efficiency, carcass characteristics, and lung scores

Bovine respiratory disease (BRD) is responsible for the majority of morbidity, mortality, and production losses occurring in feedlots. This experiment evaluated the effects of BRD incidence on subsequent finishing performance, efficiency, carcass characteristics, and lung scores of steers. Crossbred steers (n = 516) were monitored daily for clinical signs of BRD (BRD attributed morbidity and mortality were 66.5 and 13.2%, respectively). A subset of calves (n = 174) were grouped by the number of times treated for BRD (BRDX) and randomly allocated to finishing pens. The BRDX experimental groups included never treated for BRD (0X; 8 pens) and treated 1 time (1X; 8 pens), 2 times (2X; 8 pens), or 3 or 4 times (3/4X; 8 pens). Arrival BW was not different among BRDX groups (P = 0.17); however, BRDX during the receiving period decreased performance, resulting in BW of 324, 316, 285, and 260 kg for 0X, 1X, 2X, and 3/4X, respectively, at the start of finishing (P < 0.001). Ultrasound estimates, BW, and visual appraisal were used to target a common body composition (average days on feed = 182). With increasing BRDX, days on feed increased linearly (P = 0.002), whereas HCW, DP, rib eye area, QG, and unconsolidated lungs decreased linearly (P ≤ 0.03). These results suggest that with additional days on feed, calves treated multiple times for BRD are able to reach similar compositional endpoints as their untreated cohorts; however, it may not be possible for these calves to reach the same QG and carcass yield.

Ameta-analysis of effects of nutrition and management during the stocker and backgrounding phase on subsequent finishing performance and carcass characteristics

ABSTRACT The objective of this research was to conduct a meta-analysis of published studies to determine the effect of nutrition and management strategies during the stocker and backgrounding phase on subsequent finishing performance and carcass characteristics. Data sets were compiled to compare 1) the effect of calf-fed versus yearling production systems (n = 10 experiments), 2) level of dietary starch during backgrounding (n = 13 experiments), and 3) regression of subsequent finishing performance and carcass characteristics on stocker-phase ADG and initial finishing BW (n = 29 experiments). Data were analyzed using mixed-model ANOVA or regression (Proc MIXED of SAS), and least squares means or regression coefficients were weighted using the inverse of the SE of the dependent variable. Yearling cattle had greater (P ≤ 0.01) ADG and DMI but lesser G:F during finishing compared with calf-fed cattle, but there was little effect in carcass characteristics. Level of dietary starch during backgrounding had no effect on subsequent finishing performance or carcass characteristics. When adjusted for differences in initial finishing BW, ADG, and DMI, but not G:F, during finishing had a negative relationship (P ≤ 0.05) with stocker-phase ADG. Moreover, HCW, LM area, and KPH were positively related (P ≤ 0.01) with stocker-phase ADG and initial finishing BW, but when adjusted for rib fat thickness and HCW, marbling score had no relationship (P > 0.10) with stocker-phase ADG or initial finishing BW. In conclusion, previous management can influence finishing performance, with the greatest factors being production system and stocker-phase ADG, but marbling score was not affected by production system, level of dietary starch during backgrounding, or stocker-phase ADG.

Following the Integration of Diamond Particles on the Lapping-Plate Surface: Towards a More Efficient Charging Process

Even when the charging of lapping plates can extensively influence their subsequent finishing performance, the subject has been scarcely treated in specialized literature. The present paper aims to help fill such a gap and gain a better insight of the charging process. A semiquantification of the diamond particles integrated into the lapping plate surface as a function of charging time was performed by Raman spectroscopy and scanning electron microscopy, together with a simple image-analysis procedure. The corresponding evolution of surface rough features was followed from atomic force micrographs with the aid of fractal-analysis tools. It was observed that charging proceeds in two stages, both with different rates of diamond particle integration. This leads to a significant waste of diamond slurry. During the first stage, the charging ring seems to preferentially promote a further flattening of the lapping-plate surface. Diamond particles are apparently more readily incorporated into such “flattened” regions during the second stage. The results suggest a specific topographic condition must be attained before the diamond can be efficiently integrated into the lapping plate surface. A lapping-plate preconditioning step could help improve this situation and reduce the amount of abrasive waste during charging.

Effects of winter growing programs on subsequent feedlot performance, carcass characteristics, body composition, and energy requirements of beef steers12

The purpose of this study was to investigate the effects of winter growing program on subsequent finishing performance, carcass merit, and body composition of beef steers. Four steers were slaughtered to determine initial body composition. Remaining steers (n = 256) were blocked by BW and randomly allotted to 1 of 4 treatment groups: 1) ad libitum fed a high-concentrate diet (CF), 2) grazed on wheat pasture (WP), 3) fed a sorghum silage-based diet (SF), or 4) program fed a high-concentrate diet (PF). Steers in the WP, SF, and PF groups were managed to achieve approximately equal rates of BW gain. After the growing phase (112 d), 6 steers were randomly selected from the WP, SF, and PF treatments for determination of body composition. Remaining steers were adapted to a high-concentrate diet for finishing and slaughtered at 1.27 cm of 12th-rib fat. Six steers from each treatment were used to determine carcass, offal, and empty body composition. During the growing phase, WP, SF, and PF steers gained 1.15, 1.10, and 1.18 kg/d, respectively, and ME intake did not differ (P = 0.50) among treatments. Program-fed and SF steers had greater (P < 0.05) offal and empty body fat content than WP steers. Gain in offal and empty body fat was greatest (P < 0.05) for PF steers, intermediate for SF steers, and least for WP steers. During the finishing phase (123, 104, 104, 196 d for WP, SF, PF, and CF, respectively) DMI was greater (P < 0.01) for SF steers (10.9 kg/d) than for PF steers (10.1 kg/d); WP steers were intermediate (10.4 kg/d). Daily BW gain was greatest (P < 0.05) for SF steers (2.02 kg/d), intermediate for PF steers (1.85 kg/d), and least for WP and CF steers (1.64 and 1.63 kg/d, respectively). Accretion (kg/d) of carcass and empty body mass was less (P < 0.05) for WP and CF steers compared with PF and SF steers. Calf-fed steers had greater (P < 0.05) fat content of offal than SF and PF steers; WP steers were intermediate. Gain in empty body and carcass energy (Mcal/d) was greater (P < 0.05) for PF steers than CF steers with SF and WP steers being intermediate. At slaughter, SF steers had reduced (P < 0.01) yield grades and greater marbling scores compared with CF and WP steers; PF steers were intermediate. In conclusion, growing programs that increase fat composition of feeder calves did not negatively affect subsequent finishing performance. Finishing steers as calves may reduce retained energy of carcass tissues and increase internal fat during high-grain feeding compared with steers that previously underwent a growing program.

Growing rate of gain on subsequent feedlot performance, meat, and carcass quality of beef steers1

Eighty Angus and Angus x Simmental steer calves were used in a completely random design to determine the effect of rate of BW gain during the backgrounding period on subsequent feedlot performance, carcass characteristics, Warner-Bratzler shear force (WBSF), and sensory analysis. Animals were stratified by BW and allotted randomly to 1 of 10 pens (5 pens/treatment). Dietary treatments were formulated for an ADG of 0.91 kg/d [low BW gain (LG), 1.06 Mcal of NE(g)/kg] diets and 1.25 kg/d [high BW gain (HG), 1.19 Mcal of NE(g)/kg]. Steers were fed 70 d during the growing period. The LG diet consisted of 52.5% barley silage, 39.0% whole shell corn, and 8.5% supplement, whereas the HG diet contained 43.9% barley silage, 47.4% whole shell corn, and 8.7% supplement (DM basis). Initial BW (226 kg) was not different (P = 0.70) between treatments. Steers fed the HG diet had increased ADG (1.67 vs. 1.40 kg/d; P < 0.001) compared with steers fed LG diet. Dry matter intake was greater (9.49 vs. 8.35 kg/d; P < 0.001) for steers fed the HG vs. LG diet. Total backgrounding cost ($/animal) was less (P < 0.001) for those steers fed LG diet compared with HG diet ($126.00 vs. $140.35, respectively); however, total cost per kilogram of BW gain was not different (P = 0.24; $0.485/kg of BW gain). After the backgrounding period, steers were fed a common finishing diet for 135 d. During the finishing period, LG steers had similar (P = 0.12; 10.73 vs. 10.35 kg/d) DMI compared with those fed HG diets; however, ADG was not different (1.55 kg; P = 0.72) among treatments. Hot carcass weight, marbling score, 12th-rib fat, LM area, and USDA yield grade were not different (P > 0.12) between treatments and averaged 363 kg, Sm(30), 1.33 cm, 83.8 cm(2), and 2.7, respectively. There were no differences (P = 0.77; 3.63 +/- 0.12 kg) in WBSF tenderness of rib-eye steaks. Percent cooking loss was increased in LG diets (P = 0.017). No differences were observed in consumer sensory analysis of tenderness, juiciness, and flavor intensity (P > or = 0.276; 5.43 +/- 0.12, 5.07 +/- 0.13, and 5.17 +/- 0.05, respectively). These data suggest that feeding steers diets that differ in energy concentration and result in ADG of 1.4 and 1.7 kg/d during the growing period results in minimal changes in subsequent finishing performance and does not affect meat quality.

Effect of Energy Supplementation of Stocker Cattle Grazing Smooth Bromegrass Pastures on Grazing and Subsequent Finishing Performance and Carcass Traits

Grazing and subsequent finishing performance of 117 Angus stocker calves (Bos taurus; BW = 235.5 ± 1.22 kg) supplemented with 0, 0.82, or 1.64 kg/d of grain sorghum (Sorghum bicolor) on a DM basis while grazing smooth bromegrass (Bromus inermis) pastures in 2002, 2003, and 2004 were evaluated. Cattle continuously grazed pastures at a stocking rate of 2 steers/ha from mid-April to early November of each year and were then finished for slaughter and collection of carcass data. Supplementation with 0.82 or 1.64 kg/d of grain sorghum resulted in 11.2% greater (P 0.05) on forage mass, finishing ADG, or DMI during the finishing phase. Cattle supplemented during the grazing phase maintained their weight advantage through the finishing phase, were heavier (P < 0.05) at slaughter, yielded heavier (P < 0.05) carcasses, and had greater (P < 0.05) overall ADG than those that received no supplement. Cattle supplemented with 0.82 kg/d of grain sorghum required less (P < 0.05) feed per unit of gain during the finishing phase than those that were previously supplemented with 1.64 kg/d. Supplementation with 1.64 kg/d of grain sorghum during the grazing phase resulted in a greater (P < 0.05) marbling score than feeding no grazing supplement. Overall ADG from the beginning of the grazing phase through the end of the finishing phase was greater (P < 0.05) for cattle that were supplemented with grain sorghum while grazing.

Performance and meat quality of native and continental cross steers grazing improved upland pasture or semi-natural rough grazing

There is growing interest in the environmental benefits of grazing by cattle, yet little information is available regarding the levels of production that might be achieved on semi-natural rough grazing (SNRG). The overall aim of this research was to assess the performance of native and ‘improved’ breeds of cattle when grazing grass/clover swards and SNRG in order to explore potential genotype × nutritional environment interactions. This paper reports the findings of three experiments conducted over three years. The first experiment assessed the performance of autumn-born Welsh Black (WB) and Charolais cross (CX) cattle aged approximately 9 months when grazing ryegrass/white clover-dominated improved permanent pasture (PP) and Molinia caerulea-dominated SNRG. Both genotype and pasture type had significant effects on liveweight gain, with growth rates higher for WB steers than CX steers ( P < 0.001) and higher on the improved pasture than on the SNRG ( P < 0.001). The second experiment was conducted the following summer when the steers were 20 months old and evaluated the effects of breed and pasture type on subsequent finishing performance, carcass composition, meat quality, flavour and fatty acid composition. Genotype had no effect on liveweight gain during the grazing period, but pasture type again had a highly significant effect on growth rate ( P < 0.001). Carcass conformation was good and similar for both breeds. Pasture type had a greater effect on fatty acid composition of the meat than did breed. Likewise, genotype had no effect on meat colour or stability, whereas pasture type affected both. Loin steaks from the SNRG-grazed animals had significantly more vitamin E than those from PP-grazed animals ( P < 0.001) and this was reflected in lower lipid oxidation (TBARS) after simulated retail display ( P < 0.001). The third experiment assessed the performance of spring-born Welsh Black and Limousin cross steers aged 14 months when grazing PP and SNRG. Again only pasture type had a highly significant effect on growth rate ( P < 0.001). Measurements made during the first two experiments using automatic behaviour recorders indicated that pasture type influenced grazing behaviour to a greater degree than breed, and sward measurements found no between-breed differences in utilisation of M. caerulea. Overall the results indicate that the type of sward grazed has a greater influence on animal performance and meat quality than breed type when beef cattle are produced in Less Favoured Areas.

The effects of feeding flaxseed during the receiving period on morbidity, mortality, performance, and carcass characteristics of heifers1

Two experiments were conducted at the Kansas State University Beef Cattle Research Center to determine the effects of feeding ground flaxseed (flax) during the receiving period on the growth, health, and subsequent finishing performance of heifers. Crossbred heifers (Exp. 1: n = 363, 214 +/- 1 kg of initial BW; Exp. 2: n = 377, 222 +/- 1 kg of initial BW) were purchased during January and April of 2006. Heifers were fed receiving rations based on steam-flaked corn with 0, 2, 4, or 6% ground flax (DM basis) for 56 d. Following the receiving period, cattle in Exp. 1 and 2 were fed steam-flaked corn-based diets for 150 and 147 d, respectively, and then slaughtered. Heifers were implanted 91 and 109 d before slaughter for Exp. 1 and 2, respectively. In Exp. 1, DMI during the receiving period tended to increase linearly (P = 0.09) with increasing flax in the diet. Average daily gain was 1.46, 1.56, 1.58, and 1.61 kg for heifers fed 0, 2, 4, and 6% flax, respectively (linear, P = 0.03). Final BW in Exp. 1 after the finishing period was increased (linear, P = 0.04) with increasing inclusion of flax in the receiving diets. In Exp. 2, growth performance and mortality during the receiving period were not different among treatments (P > 0.12). During the receiving period in Exp. 2, incidence of the first respiratory treatment tended to be greatest (P = 0.09) for heifers fed 4% flax. During the finishing period, DMI were 8.4, 8.4, 8.0, and 8.1 kg/d for 0, 2, 4, and 6% flax, respectively (linear, P = 0.05). In Exp. 2, LM areas were greatest (quadratic, P = 0.04) for cattle fed 2% flax at receiving. In general, feeding flax during the receiving period may have the potential to improve growth performance; however, performance between experiments was variable, and many factors excluding flax feeding may have contributed to this response.

Comparison of Interseeding Lespedeza with Additional Nitrogen Fertilization on Forage Production and Steer Performance in a Wheat-Crabgrass Grazing System

Grazing and subsequent finishing performance of steers (Bos taurus) grazed on a wheat (Triticum aestivum L.)-crabgrass [Digitaria ciliaris (Retz) Koel.] system were evaluated in 1999, 2000, and 2001 to compare interseeding lespedeza (Lespedeza stipulacea Maxim.) with an additional application of N fertilizer. Hard red winter wheat was no-till seeded in fall 1998, 1999, and 2000 in pastures previously seeded to ‘Red River’ crabgrass. In early spring 1999, 2000, and 2001, additional crabgrass seed was broadcast over all pastures, and Korean lespedeza was no-till seeded in 4 pastures. All pastures received similar applications of fertilizer; however, 3 pastures not seeded with lespedeza received an additional 56kg of N/ha in mid July. Wheat grazing was initiated in mid to late March of each year. Following wheat graze-out, cattle remained on the pastures and grazed crabgrass from mid May until early September. Legume cover, forage DM production, grazing steer performance, and subsequent finishing performance were measured. Available forage DM and grazing BW gains were similar (P > 0.05) between pastures fertilized with additional N and those interseeded with lespedeza. Although there were no treatment differences (P > 0.05), there were significant (P < 0.05) year effects on BW gains. Overall grazing ADG for the wheat-crabgrass system were 0.74, 1.02, and 0.99 kg/d during 1999, 2000, and 2001, respectively. Forage production, BW grazing gains, and subsequent finishing gains were similar (P > 0.05) when pastures in a wheat-crab-grass grazing system were interseeded with lespedeza or fertilized with additional N. However, there were significant (P < 0.05) treatment x year interactions during the finishing phase.

The effects of grazing and supplemental protein concentrations during the grazing period on subsequent finishing performance and carcass quality in Japanese Black cattle steers

ABSTRACTThe effects of grazing and supplemental protein concentrations, provided during the grazing period, on subsequent finishing performance and carcass quality were investigated. This experiment was carried out using 15 Japanese Black cattle (Wagyu) steers. The steers were fed as follows: (i) grazing supplemented with moderate protein concentrate (GMP) (18% crude protein (CP); dry matter (DM) basis) before finishing, followed by feeding in a barn until slaughter; (ii) grazing supplemented with low protein concentrate (GLP) (14% CP; DM basis) before finishing, followed by feeding in the barn until slaughter; and (iii) no grazing before finishing (NG). From the end of the grazing season to the end of the growing period, the GMP and GLP steers were managed in the same way as the NG steers. All of the animals were fed the same diet in the finishing period (9 months to 28 months). None of the three treatments affected the average daily gains. For all treatments, chilled carcass weights were more than 450 kg and did not differ significantly among the groups. The longissimus muscle areas in the grazed steers were numerically larger than in those receiving the NG treatment. Fat thickness was significantly greater (P &lt; 0.05) in the NG steers than in the grazed steers. The intramuscular fat and marbling scores were not affected in the grazed steers. In conclusion, the carcass quality of grazed steers was similar to that of the NG steers at a similar final age, and the quantity of meat in the NG steers would be less than that of the GMP and GLP steers. Therefore, spring‐born Wagyu steers should be grazed using the GLP supplement before fattening.

Energy supplementation of steers grazing early-season, native range: effects on grazing and subsequent finishing performance and carcass merit (2003)

Crossbred beef steers (n = 328, initially 495 lb) were used to determine the effects of energy supplementation on grazing and subsequent finishing performance of steers grazing early-season, native range. Treatments consisted of either no supplemental energy or access to feeders containing a free choice, grainbased energy supplement. On the first day of the grazing period, steers were weighed and randomly allotted among eight pastures, providing four replications per treatment. Stocking density was 34% higher for supplemented than for unsupplemented pastures. At the end of the grazing period, steers were transported to a commercial feedlot and allowed ad libitum access to a common finishing diet for an average of 171 days. Supplement intake averaged 5.4 ± 1.1 lb/day (dry matter basis) or approximately 0.90% of body weight during the grazing period. Supplementation increased (P<0.01) grazing period gains from 1.47 to 2.20 lb/day. Supplementation also increased (P<0.01) ribeye area, back fat, and rump fat at the end of the grazing period. Supplementation did not affect subsequent finishing performance or carcass merit, but it reduced (P<0.01) time required for finishing by 18 days. Energy supplementation of steers grazing early-season, native range resulted in more pounds of gain per acre due to improved grazing performance as well as a 34% increase in stocking density.

Effect of legume persistence in endophyte-infected tall fescue pastures on forage production and steer performance (2002)

A total of 135 steers grazed highendophyte tall fescue pasture in 1998, 1999, and 2000 that had been previously interseeded with either lespedeza, red clover, or ladino clover during 1995, 1996, and 1997. Legume cover, forage dry matter production, grazing steer performance, and subsequent feedlot performance were measured. Pastures interseeded with ladino clover produced higher stocker gains in 1998 and more available forage and legume cover in all 3 years than those interseeded with lespedeza or red clover. Legume treatment had little effect on subsequent finishing performance. Results of this study indicate that lespedeza and red clover should be seeded every year and ladino clover at least every 2 years in endophyte-infected tall fescue pasture in order to provide sufficient legume to improve performance of grazing cattle.

Increasing levels of Rumensin® in limit-fed, high energy, growing diets for beef steers and effects on subsequent finishing performance (2000)

One hundred sixty-four crossbred beef steers were used to determine optimal Rumensin ® concentrations in limit-fed, high-energy, growing diets. Diets contained 30, 40, or 50 grams of Rumensin per ton of dry matter (R30, R40, and R50). Average daily gain and feed efficiency during the growing phase were not different (P>.80) among treatments. Steers that received R50 in the growing phase had the highest average daily gains during the finishing phase (P<.05). This resulted in heavier carcass weights for R50 than R30 (P<.05) and R40 (P<.12). Feed efficiencies during the finishing phase were not different among treatments (P>.40).

Effect of Interseeding Legumes into Endophyte-Infected Tall Fescue Pastures on Forage Production and Steer Performance

Grazing and subsequent finishing performances of steers (Bos taurus) (n=135) that grazed high-endophyte [Neotyphodium coenophialum Glen, Bacon, Price, and Hanlin (formerly Acremonium coenophialum)] tall fescue (Festuca arundinacea Shreb.) pastures interseeded with lespedeza (Lespedeza stipulacea Maxim.), ladino clover (Trifolium repens L.), or red clover (Trifolium pratense L.) were evaluated during 1995, 1996, and 1997. Nine 5-acre established pastures of Kentucky 31' tall fescue with approximately 70% endophyte infection were used in a randomized complete block design containing three replications of each legume treatment. Pastures were seeded with legumes each year in late winter, and steers grazed continuously from early spring to mid-fall. At the end of the grazing phase, steers were finished for slaughter. Legume cover, available forage dry matter, grazing and subsequent feedlot performances of steers, and carcass parameters were measured. Total available forage dry matter was similar among legume treatments. A significant (P 0.05) among legume treatments in 1995 and 1996. In 1997, steers grazing ladino clover pastures gained 36% more (P< 0.01) and 28% more (P < 0.01) than those grazing lespedeza and red clover pastures, respectively. Gains by steers grazing red clover and lespedeza pastures were similar. Legume treatment during the grazing phase had no effects on subsequent finishing performance. Total gains (grazing + finishing) were similar among legume treatments in 1995 and 1996; however, in 1997, steers that grazed ladino clover had higher (P < 0.01) overall gains than those that grazed red clover or lespedeza.

Growing and finishing performance by lambs differing in growth potential consuming diets during growing varying in levels of corn and rumen undegradable protein

Forty-eight 3.5-month-old lambs were used (2×2×2×2 factorial arrangement) to determine effects of corn and rumen undegradable protein (R) levels in growing diets on growing (56 days) and subsequent finishing (47 days) performance by lambs differing in growth potential. During the growing phase, the basal diet consisted of bermudagrass ( Cynodon dactylon L.) hay (8% CP) consumed ad libitum and 0.3% BW of soybean meal. Factors investigated were: 1.0 vs 2.5% BW (LC and HC, respectively) of ground corn; 0 vs 0.5% BW (S and SR, respectively) of a mixture of fish, feather, and blood meals (36, 27, and 37%, respectively); ewes vs wethers (17.9±0.63 and 19.2±0.66 kg initial BW, respectively); and Romanov (RV) × St. Croix vs Suffolk (SU) × St. Croix (18.2±0.61 and 18.7±0.63 kg initial BW, respectively). During the finishing phase, all lambs consumed ad libitum the same 80% concentrate, 20% CP diet. Dry matter intakes during growing (0.83, 0.96, 0.97, and 0.97 kg/day; SE=0.023) and finishing (1.47, 1.67, 1.66, and 1.56 kg/day for LC–S, LC–SR, HC–S, and HC–SR, respectively; SE=0.052) were affected by interactions ( p=0.05) between corn and R levels. Corn and R levels increased ( p≤0.02) mass of fat (4.68, 5.82, 6.25, and 7.02 kg; SE=0.271) and protein (3.91, 4.11, 4.15, and 4.40 kg for LC–S, LC–SR, HC–S, and HC–SR, respectively; SE=0.031) after growing, although effects, particularly those of corn level, varied with sire breed [fat: 5.49, 5.01, 6.13, and 7.15 kg (SE=0.286); protein: 4.07, 3.96, 4.18, and 4.37 kg for RV–LC, RV–HC, SU–LC, and SU–HC, respectively (SE=0.065)]. Dietary corn level during growing increased accretion of empty BW [268, 258, 289, and 276 g/day; SE=9.3 ( p=0.10)] and fat [151, 152, 167, and 164 g/day for LC–S, LC–SR, HC–S, and HC–SR, respectively; SE=5.9 ( p=0.08)] during finishing. In conclusion, different concentrate levels and types during growing may comparably affect growth during growing, but can have dissimilar impact on finishing performance, and such effects are more likely to vary with growth potential as affected by genotype than gender.

Effects of previous grazing nutrition and management on feedlot performance of cattle

Management strategies designed to improve grazing animal performance can influence feedlot performance and carcass traits both positively and negatively. In spite of the economic relevance of potential interactions between grazing and finishing performance, controlled experiments evaluating integrated production systems are limited in number. Effects of grazing treatments can result from, or be overshadowed by, changes in gut fill, thus making it difficult to assign precise costs to different phases of production. Published reports have considered the effects of stocking rate, duration of grazing, forage characteristics, supplementation, and growth-promoting implants on subsequent finishing performance. Improvements in cattle performance attributed to changes in stocking rate generally have been neutral to positive with respect to effects on finishing performance. Comparisons among forages have led to the suggestion that forage species may contribute to differences in gastrointestinal fill of grazing cattle, thereby influencing gain and efficiency during the subsequent finishing phase. Creep-feeding suckling calves generally has increased preweaning performance but has had relatively little influence on performance during the subsequent finishing phase. Grain supplementation of stocker cattle during the grazing period has improved grazing performance, but effects on subsequent feedlot performance have been inconsistent. Potential carryover effects from protein and mineral supplementation also have been inconclusive. Lack of congruence among studies is puzzling but may be the consequence of highly varied production systems, differences in experimental procedures, and changes in gut fill or mass of internal organs. Based on the studies reviewed, the expression or absence of compensatory growth during the finishing phase appears to be related to the nutritional quality of forages utilized in the grazing period, with higher quality forages tending to yield greater compensatory effects. The bulk of evidence with suckling cattle and stocker implants suggests that effects on subsequent finishing performance are minimal. Attention is drawn to the noticeable lack of research pertaining to integrated production systems. A more thorough understanding of the interactions among grazing nutrition and management, finishing performance, and carcass traits is needed to facilitate greater economic exploitation of these relationships.