FORAGES AND PASTURES SYMPOSIUM: Optimizing the use of fibrous residues in beef and dairy diets

Effect of beef heifer development systems utilizing corn residue and late summer planted cover crops on growth, reproductive performance, and economics

The objective of this study was to evaluate growth and reproductive performance of heifers developed using 3 different winter systems in the midwestern U.S. Spring-born heifers (n = 1,156; 214 d of age; SD ± 17 d) were used in a 3-yr study to evaluate performance in winter development systems, which utilized cover crop (CC) and corn residue grazing. Heifers were assigned to 1 of 3 treatments: grazing corn residue with 0.77 kg/d dried distillers grains (CD) or 1.69 kg/d wheat midds (CW) supplementation followed by a grower ration in the drylot, or grazing late summer planted oat-brassica CC followed by corn residue grazing with 0.35 kg/d dried distillers grains supplementation (CC). Supplementation during the corn residue phase was targeted to result in a common body weight (BW) (276 kg; ~45% of mature BW) by the end of the winter development period. Grazing of corn residue (CD and CW) and CC began in early November. After 63 d, heifers assigned to CC were moved to corn residue; on day 77 heifers assigned to CD and CW began receiving a grower ration in the drylot. In mid-February (day 98), heifers were comingled and managed in a single group. Breeding season began in June and lasted for 29 d. The ADG of heifers assigned to CC when grazing CC (days 1 to 63) was greater (0.76 kg/d; P < 0.01) than those assigned to CD or CW (0.58 kg/d and 0.49 kg/d, respectively). Gain during the last 35 d of the winter period for heifers assigned to CC (0.36 kg/d) was less (P < 0.01) than those assigned to CW (0.49 kg/d) but not different from CD heifers (0.41 kg/d). Overall (days 1 to 98), winter ADG was greater (P < 0.05) for heifers assigned to CC (0.62 kg/d) than CD (0.53 kg/d) or CW (0.50 kg/d), which did not differ (P = 0.42). Percent of mature BW in May (27 d pre-breeding) was greater (P < 0.01) for heifers assigned to CC (52%) than for those on CD and CW (50%), which did not differ (P = 0.64). Pregnancy rates were affected by treatment (P < 0.03), with heifers assigned to CC (76%) being greater than CW (64%) and CD heifers being intermediate (70%). When accounting for the differences in cost and the value of open and bred heifers, the economic return tended to differ (P = 0.07) among treatments, with CC and CW not differing (P ≥ 0.20) from CD but return for CC being $73 greater than CW (P = 0.02). Utilizing oat-brassica CCs early in the winter followed by a slower rate of gain while grazing corn residue with distillers supplementation appears to be as effective for developing beef heifers in the midwestern U.S. as supplementing distillers grains.

Effects of corn straw on meat characteristics of lambs in the Brazilian semi-arid region

The present study aimed to evaluate the influence of increasing levels of corn straw replacement of sorghum silage on average daily gain, loin eye area, subcutaneous fat thickness, weight of commercial cuts, leg tissue composition, and physico-chemical characteristics of the meat from F1 Santa Inês × Dorper lambs maintained in a feedlot system. Treatments consisted of 0, 33, 66 and 100% corn straw replacement of sorghum silage. There were thirty-six 150-day-old male lambs. Corn straw replacement of sorghum silage in lamb feed reduced the average daily gain and weight of the ribs, besides promoting a quadratic influence on leg fat content. However, there was no influence on commercial carcass cuts, leg muscle index, leg tissue composition, and physico-chemical characteristics of the meat. Thus, corn straw can be used as alternative feedstuff for sheep rations to improve the production of high-quality sheep meat in semi-arid regions.

Intake of corn stover botanical parts by growing and finishing beef steers

Single-pass corn stover harvest is a method whereby combine harvester tailings consisting of cob, stalk, leaf, husk, and tassel fractions are collected and baled without coming into contact with soil. The objective was to feed beef steers diets that included a roughage component consisting of harvested corn residue in chopped form from conventional corn stover bales (CST) or single-pass bales (SPB) to assess intake selectivity of corn stover fractions and estimate net energy values of these corn stovers. Whole plant corn silage served as the control roughage in the control diet (CSIL). Steers (n = 90, 5 pens per treatment) were fed during Grow (84 d) and Finish (66 d) trials. Steers sorted through corn stover during both trials and consumed 52.5% of corn stover offered and 40% of cob offered. Intake of SPB cob was 2.6-fold and 3.3-fold greater than CST cob intake (P < 0.01) in Grow and Finish trials, respectively, indicating that when more cob was available, cattle consumed more. During the Grow trial, stover intake tended (P = 0.07) to be lower for SPB and diet dry matter intake (DMI) was less (P ≤ 0.05) for SPB, which may be due to the elevated cob intake by SPB steers. Across treatments, stover DMI was similar in the Grow (1.10 kg per steer per d) and Finish (1.11 kg per steer per d) trials. The proportion (65%) of Fines (<8 mm) consumed from the Grow diet (40% neutral detergent fiber, aNDF) was greater than the Finish diet (25% aNDF; 18% to 31%) and gleaning of concentrate feeds from orts seemed to be more extensive in the Grow diet. Steers consuming Finish diets containing SPB and CST had DMI that were 17% and 18%, respectively, greater (P ≤ 0.05) than CSIL, an indication of compensatory intake. The physical effectiveness factors for stovers fed in the Grow and Finish diets were 0.85 and 0.95, respectively. Estimates for net energy maintenance and net energy gain (NEg), respectively, using National Research Council methods from 2001 were as follows for consumed stovers: SPB (1.09 and 0.54 Mcal/kg) and CST (0.98 and 0.44 Mcal/kg) in the Grow trial, and SPB (0.96 and 0.42 Mcal/kg) and CST (0.95 and 0.40 Mcal/kg) in the Finish trial. Although SPB and CST differ in botanical fraction composition and net intakes of botanical fractions, their energetic contributions to steer performance were very similar. Steers fed the Finish diet (1.25 Mcal performance-adjusted NEg per kg) selected stover botanical components to achieve a diet composition of 25% aNDF.

Ruminal in situ degradability of forage components and in vitro organic matter digestibility of warm-season grasses treated with calcium oxide

An experiment was designed to evaluate the effects of CaO on ruminal in situ degradability (RISD) of forage components and in vitro organic matter digestibility (IVOMD) of warm-season forages. Bahiagrass (Paspalum notatum; BH) or Tifton 85 bermudagrass (Cynodon spp.; BM) hay were stored in 20-L buckets in two consecutive years (n = 4/treatment) as follows: 1) untreated dry BH or BM (DH); 2) hydrated BH or BM stored for 7 d (W7); 3) hydrated BH or BM stored for 14 d (W14); 4) hydrated BH or BM + 5% [dry matter (DM) basis] CaO stored for 7 d (CO5-7); 5) hydrated BH or BM + 5% (DM basis) CaO stored for 14 d (CO5-14); and 6) hydrated BH or BM + 10% (DM basis) CaO stored for 14 d (CO10). With exception of the dry treatment (DH), tap water was added to forages under the remaining treatments to reach a DM concentration of 50%. Ruminal in situ degradability of DM, organic matter (OM), crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) of BH and BM was determined for 24, 48, and 72 h in two ruminally cannulated steers consuming BH. Data were analyzed as a randomized block design using bucket as the experimental unit. The model included the fixed effect of treatment and the random effect of year. Concentration of NDF was reduced (P < 0.001) when BH and BM were treated with 10% and 5% CaO and compared with DH. However, only CO10 promoted a reduction (P = 0.007) in ADF concentration of BH, whereas CO10 and CO5, regardless of storage length, reduced (P ≤ 0.006) ADF concentration of BM, when compared with DH. At all ruminal incubation time points, a treatment effect (P < 0.001) was observed on RISD of DM, OM, CP, NDF, and ADF of BH and BM, where all treatments containing CaO promoted greater degradability when compared with DH, W7, and W14, which did not differ (P > 0.05). Ruminal degradability of forage components was greatest (P < 0.05) for CO10, followed by CO5-7 and CO5-14, which did not differ (P > 0.05). In vitro organic matter digestibility was increased (P < 0.001) in both BH and BM when CaO was applied and compared to DH. Treatment of BH and BM with CaO seems to be an effective method of promoting increased digestibility of forage components, including fiber fractions, when applied at 5% of the forage DM with potential additional benefits to BH when applied at 10%.

Performance of growing beef cattle consuming bahiagrass hay treated with calcium oxide and molasses

Two experiments were conducted to evaluate the effects of Pensacola bahiagrass (Paspalum notatum) hay treated with calcium oxide (CaO) and molasses on performance of growing beef cattle supplemented or not with cottonseed meal. In Exp. 1, growing Bos indicus influenced heifers (n = 59; 250 ± 29 kg body weight [BW]) and steers (n = 37; 256 ± 45 kg BW) were used. In Exp. 2, heifers (n = 56; 249 ± 26 kg BW) and steers (n = 8; 249 ± 20 kg BW) from Exp. 1 were used. Both experiments were randomized complete block designs and consisted of 56-d periods in which cattle were weighed every 14 d. On day 0, cattle were weighed after a 16-h water and feed withdrawal, stratified by sex, breed, and BW, and blocked by initial BW. Cattle were allotted to 24 and 16 dormant bahiagrass pastures (1.34 ha each) in Exp. 1 and Exp. 2, respectively. Pastures were located in two different areas within 0.52 km of each other and were stratified by location and randomly assigned (n = 8 pastures/treatment) to treatment. In Exp. 1 treatments were: 1) untreated dry hay (DH); 2) hay treated with 10% molasses (dry matter [DM] basis) + water (to 65% DM; MOL); or 3) hay treated with 5% CaO (DM basis) + 10% molasses (DM basis) + water (to 65% DM; CAO). In Exp. 2 only treatments MOL and CAO were applied, and cottonseed meal was provided at 0.3% of cattle BW/d (as fed basis). In both experiments, data were analyzed using pasture as the experimental unit. The model included the fixed effects of treatment, sex, and their interaction (Exp. 1). Location and block were included as random effects. In both experiments, initial and final BW were not affected by treatment (P ≥ 0.362 and P ≥ 0.283, respectively) or sex (P ≥ 0.512 and P ≥ 0.495, respectively) and no treatment × sex interaction was observed in Exp. 1 (P > 0.05). Additionally, no effects of treatment (P ≥ 0.515), sex (P ≥ 0.285), or treatment × sex interaction (Exp. 1; P = 0.582) were observed on average daily gain (average of −0.03 kg in Exp. 1 and 0.537 kg in Exp. 2). Bahiagrass hay treated with molasses alone or in combination with CaO failed to improve performance of growing beef cattle. However, when protein supplementation via cottonseed meal was provided, cattle did not experience weight loss.

The Effects of Oil Palm Fronds Silage Supplemented with Urea-Calcium Hydroxide on Rumen Fermentation and Nutrient Digestibility of Thai Native-Anglo Nubian Goats

This study aimed to examine the combined effects of urea and calcium hydroxide ensiled oil palm fronds on rumen fermentation and digestibility of Thai native-Anglo Nubian goats. A 4 × 4 Latin square design was used to randomly assign four male crossbred goats (Thai native × Anglo Nubian). The dietary treatments were as follows: ensiled oil palm frond with no additives (EOPF as the control), urea 5% (50 g/kg fresh matter) (E-UOPF 5%), calcium hydroxide (Ca(OH)2) 5% (50 g/kg fresh matter) (E-CaOPF 5%), and combination of urea 2.5% (25 g/kg fresh matter) with Ca(OH)2 (25 g/kg fresh matter) (E-UCOPF 2.5%). The oil palm frond ensiled with different additives did not change the DM intake (p > 0.05). The total TMR intakes range from 69.39 to 77.09 g/kg BW0.75. The goats fed with E-UOPF 5.0% consumed significantly more CP than the other groups (p < 0.05). The E-UCOPF increased ME intake by 4.8%, compared with the control treatment (p < 0.05). E-UOPF 5% and E-UCOPF 2.5% significantly increased the CP digestibility by 19.7% and 17.1%, respectively (p < 0.05). Furthermore, E-CaOPF 5.0% and E-UCOPF 2.5% improved the NDF digestibility by about 10.9% and 9.90%, respectively (p < 0.05). The urea-containing oil palm frond (E-UOPF 5.0% and E-UCOPF 2.5%) had higher blood urea nitrogen (BUN) than the other groups (p < 0.05). The TVFA of goats fed E-UCOPF 2.5% was approximately 15.8% higher than that of goats provide EOPF (p < 0.05). The mean concentration of C3 increased by 7.90% and 11.61%, respectively, when E-CaOPF 5.0% and E-UCOPF 2.5% were provided instead of EOPF (p < 0.05). The total N intake and absorbed were highest (p < 0.05) when goats offered E-UOPF 5.0% (p < 0.05). The goats fed oil palm frond without additives had the lowest percentage of N-absorption/N intake (p < 0.05). This study clearly shows that the most suitable treatment is E-UCOPF 2.5%, which enhances DMD, nutrient digestibility, TVFAs, and nitrogen balance and has no negative effects on rumen microbes. This indicates that E-UCOPF 2.5% may be utilized as an alternate roughage source in TMR diets, accounting for at least 40% of the OPF. However, several factors still require consideration for urea-Ca(OH)2 treatments to be successful, including other concentrations of urea, moisture content, duration of pre-treatment, and the metabolizable protein system.

Omega-6 Fatty Acids: A Sustainable Alternative to Improve Beef Production Efficiency

Simple Summary

The global beef industry is currently challenged with improving production efficiency while fostering judicious use of limited natural resources. Sustainable management systems are warranted to ensure that worldwide demands for beef and ecological stewardship are met. Supplementing cattle with omega-6 fatty acids is a nutritional intervention shown to sustainably enhance productivity across different sectors of the beef industry. The purpose of this review is to discuss recent research that describes the advantages of supplementing omega-6 fatty acids on traits that are critical to beef production efficiency, including reproduction, immunocompetence, growth, and quality of carcass and beef products.

Abstract

Global beef production must increase in the next decades to meet the demands of a growing population, while promoting sustainable use of limited natural resources. Supplementing beef cattle with omega-6 fatty acids (FAs) is a nutritional approach shown to enhance production efficiency, with research conducted across different environments and sectors of the beef industry. Omega-6 FA from natural feed ingredients such as soybean oil are highly susceptible to ruminal biohydrogenation. Hence, our and other research groups have used soybean oil in the form of Ca soaps (CSSO) to lessen ruminal biohydrogenation, and maximize delivery of omega-6 FA to the duodenum for absorption. In cow–calf systems, omega-6 FA supplementation to beef cows improved pregnancy success by promoting the establishment of early pregnancy. Cows receiving omega-6 FA during late gestation gave birth to calves that were healthier and more efficient in the feedlot, suggesting the potential role of omega-6 FA on developmental programming. Supplementing omega-6 FA to young cattle also elicited programming effects toward improved adipogenesis and carcass quality, and improved calf immunocompetence upon a stress stimulus. Cattle supplemented with omega-6 FA during growing or finishing periods also experienced improved performance and carcass quality. All these research results were generated using cattle of different genetic composition (Bos taurus and B. indicus influenced), and in different environments (tropical, subtropical, and temperate region). Hence, supplementing omega-6 FA via CSSO is a sustainable approach to enhance the production efficiency of beef industries across different areas of the world.

Performance of cows and summer-born calves and economics in semi-confined and confined beef systems

Objectives

Cow and calf performance in a semi-confined cow-calf production system was compared with total confinement using summer-born calves.

Material and Methods

The experiment was conducted over 3 yr in eastern Nebraska (ENREC) and 2 yr in western Nebraska (PREC) in a randomized complete block design. Lactating, crossbred beef cows (n = 127 at ENREC; n = 56 at PREC) with summer-born calves were used from November to April. Treatments were (1) dry-lot feeding or (2) cornstalk grazing with supplementation. Dry-lot pairs were limit fed a crop residue and distillers–based diet to meet energy requirements of a lactating cow. A dried distillers grain–based pellet was supplemented to pairs on cornstalks at a rate of 2.4 kg of DM/pair daily. Dry-lot cow-calf pairs were limit fed 12.1 kg of DM/d throughout the trial.

Results and Discussion

At ENREC, cows wintered on cornstalks lost BW and had a 0.46-unit decrease in BCS (P < 0.01), whereas cows in the dry-lot gained BW and had a 0.24-unit increase in BCS. At PREC, BCS increased by 0.03 units for cows wintered in the dry-lot and decreased by 0.26 units for cows wintered on cornstalks (P < 0.04). At both locations, calves fed in a dry-lot had greater ADG and BW per day of age compared with calves offered cornstalk grazing with supplementation (P ≤ 0.03).

Implications and Applications

A partial budget suggests that lower winter production inputs compensate for reduced performance of calves when cow-calf pairs are wintered on cornstalks, making residue grazing a viable option in partial confinement systems.

Effects of supplement type and narasin inclusion on supplement intake by Bos indicus beef bulls grazing a warm-season forage

This study aimed to evaluate the effects of supplement type and narasin inclusion on the frequency and supplement intake of grazing Bos indicus beef bulls. Four hundred animals were ranked by initial BW (383 ± 35 kg) and allocated into one of four paddocks of Brachiaria brizantha cv. Marandú (100 animals/paddock). Paddocks were randomly assigned to receive either a mineral salt (MIN) or a protein-energetic supplement (PREN) containing or not narasin (N) for a 90-d period. An individual electronic data capture system with 11 feed bunks was used to individually measure supplement intake and meal frequency in each paddock. The evaluations and analysis of individual intake, frequency of visits to the feeder, and intake per visit (I/V) were performed every 15 d and classified as periods (PR1 through PR6). All data were analyzed as a 2 × 2 factorial design with the PROC MIXED procedure of SAS. A supplement type × N × PR interaction was observed (P < 0.0001) for daily supplement intake. No differences were observed between MIN, whereas PREN had a greater (P ≤ 0.03) supplement intake on PR1 and PR3, but a reduced supplement intake on PR6 compared with PREN + N (P = 0.02). Moreover, no supplement type × N interaction (P = 0.47) or N (P = 0.44) effects were observed for daily supplement intake in the present study. A supplement type × N × PR interaction was detected (P < 0.0001) for the frequency of visits in the feeders. Throughout the experimental period, animals from the MIN + N had a greater (P ≤ 0.02) frequency of visits compared with MIN cohorts. A supplement effect was detected for I/V (P = 0.02), whereas neither a narasin effect (P = 0.74) nor interactions (P ≥ 0.16) were observed. Animals offered PREN had a greater I/V when compared with MIN cohorts (145 vs. 846 g/d for MIN and PREN, respectively; SEM = 16.1). When these data are reported as percentage of days visiting the feeder within each PR, MIN and MIN + N animals visited the feeder for 25.8% and 35.9% of the days, respectively. Conversely, no differences were observed (P = 0.65) in the overall mean visits per PR between PREN and PREN + N (12.8 vs. 12.3 d for PREN and PREN + N, respectively; SEM = 0.195). As percentage of days visiting the feeder, PREN and PREN + N visited the feeder for 85.1% and 81.9% of the days, respectively. In summary, narasin inclusion did not reduce supplement intake, regardless of supplement type, but increased the frequency of visits to the feeder for the MIN treatment.

Effect of corn residue harvest method with ruminally undegradable protein supplementation on performance of growing calves and fiber digestibility

Two experiments evaluated the effects of corn residue harvest method on animal performance and diet digestibility. Experiment 1 was designed as a 2 × 2 + 1 factorial arrangement of treatments using 60 individually fed crossbred steers (280 kg [SD 32] initial BW; = 12). Factors were the corn residue harvest method (high-stem and conventional) and supplemental RUP at 2 concentrations (0 and 3.3% diet DM). A third harvest method (low-stem) was also evaluated, but only in diets containing supplemental RUP at 3.3% diet DM because of limitations in the amount of available low-stem residue. Therefore, the 3 harvest methods were compared only in diets containing supplemental RUP. In Exp. 2, 9 crossbred wethers were blocked by BW (42.4 kg [SD 7] initial BW) and randomly assigned to diets containing corn residue harvested 1 of 3 ways (low-stem, high-stem, and conventional). In Exp. 1, steers fed the low-stem residue diet had greater ADG compared with the steers fed conventionally harvested corn residue ( = 0.03; 0.78 vs. 0.63 kg), whereas steers fed high-stem residue were intermediate ( > 0.17; 0.69 kg), not differing from either conventional or low-stem residues. Results from in vitro OM digestibility suggest that low-stem residue had the greatest ( < 0.01) amount of digestible OM compared with the other 2 residue harvest methods, which did not differ ( = 0.32; 55.0, 47.8, and 47.1% for low-stem, high-stem, and conventional residues, respectively). There were no differences in RUP content (40% of CP) and RUP digestibility (60%) among the 3 residues ( ≥ 0.35). No interactions were observed between harvest method and the addition of RUP ( ≥ 0.12). The addition of RUP tended to result in improved ADG (0.66 ± 0.07 vs. 0.58 ± 0.07 for supplemental RUP and no RUP, respectively; = 0.08) and G:F (0.116 ± 0.006 vs. 0.095 ± 0.020 for supplemental RUP and no RUP, respectively; = 0.02) compared with similar diets without the additional RUP. In Exp. 2, low-stem residue had greater DM and OM digestibility and DE ( < 0.01) than high-stem and conventional residues, which did not differ ( ≥ 0.63). Low-stem residue also had the greatest NDF digestibility (NDFD; < 0.01), whereas high-stem residue had greater NDFD than conventional residue ( < 0.01). Digestible energy was greatest for low-stem residue ( < 0.05) and did not differ between high-stem and conventional residues ( = 0.50). Reducing the proportion of stem in the bale through changes in the harvest method increased the nutritive quality of corn residue.

The effects of backgrounding system on growing and finishing performance and carcass characteristics of beef steers

The objective of this 2-yr study was to evaluate growing and finishing performance as well as carcass characteristics of spring-born steers backgrounded on 3 different systems, using feedstuffs readily available in the Midwest: 1) grazing corn residue and being supplemented with dried distillers plus solubles at 2.68 kg DM/steer 6 d/wk (RESIDUE), 2) grazing a late summer-planted oat-brassica forage mix (CCROP), or 3) being fed a corn silage-based diet in a drylot (DRYLOT). Steers ( = 715) were stratified by BW (278 kg ± 23 in yr 1 and 291 kg ± 91 in yr 2) and assigned to treatment and replicate (4 replications per treatment per yr). Steers assigned to DRYLOT were fed a corn silage-based diet for 54 d in yr 1 and 52 d in yr 2 before being transitioned to the finishing diet. Steers assigned to RESIDUE and those assigned to CCROP grazed 65 d in yr 1 and 66 d in yr 2 and then were fed a corn silage-based diet for 21 d in yr 1 and 33 d in yr 2 before being transitioned to the finishing diet. During backgrounding, the ADG (SEM 0.022) of steers assigned to DRYLOT (1.48 kg/d) was greater ( < 0.01) than that of steers assigned to both CCROP (1.05 kg/d) and RESIDUE (0.87 kg/d) and ADG of steers assigned to CCROP was greater ( < 0.01) than that of steers assigned to RESIDUE. At the start of the finishing period, BW of steers assigned to CCROP (381 kg) was greater ( < 0.01, SEM 2.5) than that of steers assigned to DRYLOT (361 kg) and RESIDUE (366 kg). The finishing period lasted 160 d for all treatments. Both 12th-rib fat ( = 0.89) and calculated yield grade ( = 0.39) did not differ among treatments. Finishing G:F of steers assigned to DRYLOT (0.162 kg/kg) was greater ( < 0.01, SEM 0.0015) than that of steers assigned to RESIDUE (0.153 kg/kg) and CCROP (0.153 kg/kg), which did not differ ( = 0.79). In yr 1, HCW of steers assigned to CCROP (402 kg) was greater ( < 0.01, SEM 2.1) than that of steers assigned to both RESIDUE (389 kg) and DRYLOT (391 kg), which did not differ ( = 0.40). This difference in HCW is most likely a result of differences in BW at the start of the finishing phase in yr 1. However in yr 2, HCW of steers assigned to CCROP (400 kg) and RESIDUE (397 kg) did not differ ( = 0.26, SEM 2.1) but were greater ( < 0.01) than that of steers assigned to DRYLOT (367 kg), despite the fact that steers assigned to RESIDUE entered the finishing phase at a lighter BW than steers assigned to CCROP. Marbling was greater ( = 0.01, SEM 3.9) for steers assigned to DRYLOT (429) than for steers assigned to RESIDUE (414), although steers assigned to CCROP (424) were not different ( ≥ 0.10) from steers assigned to DRYLOT or RESIDUE. When cost and price scenarios from the last 5 yr were conducted, no treatment appeared to be consistently superior in terms of cost of gain or net return. Therefore, all 3 systems appear to be viable options for producers.

Effects of processing treated corn stover and distillers' grains on performance and total tract digestion of finishing cattle

Two studies evaluated effects of replacing corn with a pellet containing alkaline treated corn stover, dried distillers' grains plus solubles (DDGS), and distillers' solubles on total tract digestion and performance of finishing cattle. Experiment 1 used 4 ruminally fistulated steers in a 4 × 6 Latin rectangle to evaluate total tract digestion. Treatments consisted of a control (CON) containing 50.3% dry-rolled corn (DRC), 40% modified distillers' grains plus solubles (MDGS), and 5% untreated corn stover. The next 2 treatments replaced 25% DRC (DM basis) with either a CaO-treated stover pellet (STOVPEL) or a pellet consisting of 64% CaO-treated corn stover, 18% DDGS, and 18% corn distillers' solubles (COMBPEL). The last treatment replaced 25% DRC with a mixture of feeds: 10% treated stover pellet, 10% DDGS, and 5% distillers' solubles (COMB). Experiment 2 used 336 crossbred steer calves (301 ± 25 kg initial BW) in a 2 × 3 + 1 factorial to evaluate effects of replacing corn with a pellet containing 64% CaO-treated corn stover, 18% DDGS, and 18% corn distillers' solubles on finishing performance. Factors included level of MDGS (20 or 40%) and pellet inclusion (10, 20, or 30%). The CON diet contained a 50:50 blend of DRC and high-moisture corn and 40% MDGS. All diets contained 5% wheat straw and 4% dry meal supplement. In Exp. 1, no differences ( ≥ 0.50) were observed between the CON, STOVPEL, COMB, or COMBPEL treatments for DM (76.5, 75.4, 72.5, and 78.0%, respectively; SEM 2.5) or OM (79.1, 79.7, 75.7, and 80.5%, respectively; SEM 2.4) digestibility. In Exp. 2, a linear increase ( = 0.03) in DMI was observed as pellet inclusion increased from 0% in the CON (10.6 kg/d [SE 0.13]) to 30% (11.0 kg/d [SE 0.13]) in treatments containing 40% MDGS. A quadratic response ( = 0.03) in DMI was observed as pellet inclusion increased in diets containing 20% MDGS due to greater DMI of the 20% pellet treatment. A linear decrease ( = 0.03) in G:F was observed as the level of pellet inclusion increased from 0 (0.182 [SE 0.02]) to 30% (0.175 [SE 0.02]) in diets containing 40% MDGS. In diets containing 20% MDGS, no differences ( ≥ 0.22) in G:F were observed as pellet inclusion increased from 10 to 30%. In conclusion, replacing up to 20% of corn (DM basis) in diets containing 20% MDGS had minimal impact on performance. Conversely, up to 30% of corn could be replaced in diets containing 40% MDGS with little impact on performance.

Supplementation of corn dried distillers grains plus solubles to gestating beef cows fed low-quality forage: I. Altered intake behavior, body condition, and reproduction

To investigate the effects of corn dried distillers grains plus solubles (DDGS) supplementation to cows fed corn stover and silage during late gestation, 27 multiparous beef cows (674 ± 17 kg; BCS, 5.6 ± 0.1) were divided randomly into 2 pens equipped with electronic feeders. For 10 wk, both groups were fed the basal diet for ad libitum intake while 1 group was supplemented (SUP; = 12) with DDGS at 0.3% of BW (DM basis). Following parturition, all cows received the same diet for an additional 8 wk. During gestation, SUP cows gained BW ( < 0.01), and there was no change in BCS ( 0.79). Nonsupplemented (CON) cows tended to lose BW ( 0.06) and lost BCS ( < 0.01) during gestation. Supplemented cows consumed more forage ( 0.01) and total feed than CON cows. An interaction of treatment and day was observed for time spent consuming forage ( < 0.01); SUP cows consumed forage faster than CON cows ( ≤ 0.01) early in gestation. Control cows ate more meals than SUP cows ( = 0.06) from d 201 to 218 of gestation. Supplemented cows tended ( = 0.09) to consume larger meals than CON cows and spent more ( < 0.01) time eating than CON cows around d 240 of gestation. Calves born to SUP cows tended ( = 0.06) to be heavier than calves born to CON cows. During lactation, both groups gained ( < 0.01) BW. Body condition score was less ( < 0.05) in CON cows than it was in SUP cows at the end of the study. Dry matter intake during lactation increased ( < 0.01) over time but was not influenced ( = 0.44) by treatment. Supplemented cows spent more time ( < 0.01) eating than CON cows after wk 4 of lactation, and they ate faster than CON cows until wk 3 of lactation whereas CON cows ate faster than SUP cows after wk 6 of lactation ( 0.01). The number of meals increased with advancing lactation ( < 0.01) and CON cows averaged more meals daily than SUP cows ( = 0.01). Conversely, meal size decreased as lactation advanced ( < 0.01), and SUP cows consumed larger meals than CON cows ( = 0.05). Supplementation with DDGS during gestation influenced intake behavior during gestation and lactation as well as the maintenance of maternal BW and BCS and calf birth BW.