EVALUATION OF PROTEIN AND FIBER FROM DISTILLERS GRAINS PLUS SOLUBLES IN FINISHING BEEF CATTLE DIETS

Four studies were conducted to evaluate the components of distillers grains plus solubles in finishing beef cattle diets. Experiment 1 evaluated the effects of five composites of feedstuffs formulated to be similar in nutrient composition to DDGS on finishing performance of cattle. Experiment 2 evaluated isolating the protein from distillers grains using a feedstuff from the wet milling ethanol industry to determine the impacts of protein on the feeding value of WDGS in finishing performance of cattle. Experiments 3 and 4 evaluated the effects of protein from distillers grains with the diets used in Exp. 2 on site of digestion, ruminal VFA concentration and pH. In Exp. 1, replicating distillers grains plus solubles with proportions of high-protein distiller grains, corn bran, and condensed distillers solubles did not result in similar performance as cattle fed distillers grains plus solubles. Cattle consuming the CaO treated corn stover and byproducts were less efficient than cattle fed the composite with corn bran. Replacing high-protein distillers grains from the composite diet with condensed distillers solubles and corn bran resulted in greater DMI and tended to improve feed efficiency. In Exp. 2, protein made up a large portion of the calculated feeding value of the distillers grains plus solubles. In Exp. 3 and 4, DM and NDF total tract digestibility were greater for protein of distillers grains than for distillers grains plus solubles. Excess protein, from distillers grains plus solubles, above the animals requirement does serve as an energy source to beef cattle on finishing diets. Advisors: Jim C. MacDonald and Matt K. Luebb

Evaluation of Two Implant Strategies, Revalor- XH or a Combination Revalor- IH/Revalor- 200 on Heifer Growth Performance and Carcass Characteristics

A commercial feedlot trial examined effects of two implant strategies (Revalor- IH on d 1 and re- implanted with Revalor- 200 on d 101 or Revalor- XH on d 1) on growth performance and carcass characteristics of heifers fed 183 days. Th ere were no differences between implant strategies for final body weight, dry matter intake, and average daily gain. Heifers implanted with the combination IH/200 treatment had improved carcassadjusted feed conversion, greater LM area, and lower calculated yield grade compared to heifers implanted with XH. Th e response in growth performance between the two implant strategies suggests that the partiallycoated Revalor- XH implant can be used in place of a more aggressive implant strategy when heifers are fed to similar days

Impact of Corn Silage Inclusion on Finishing Cattle Performance

Cattle fed high grain diets with little to no roughage are typically at greater risk for acidosis and reduced dry matter intake and average daily gain. An individual feeding study was conducted to compare different inclusions of corn silage used as a roughage source on finishing performance and liver abscess rate. Treatments consisted of 3 inclusions of corn silage at 0, 7.5 and 15% of the diet DM and a control treatment with 7.5% alfalfa. There were no differences for live animal performance or carcass characteristics. There were also no differences in liver abscess incidence. Feeding corn silage at 15% gave similar performance responses compared to 7.5% alfalfa. These data suggest that roughage is not required in a finishing diet when feeding individual animals

Effects of Supplemental SoyPass in Forage-Based Diets Containing Distillers Grains on Performance of Growing Steers

SoyPass was supplemented in two grass hay diets containing 20% or 35% wet distillers grains with solubles (WDGS) to analyze the effects on growing cattle performance. The SoyPass supplement replaced 0, 30, or 60% of dietary WDGS for a total of 6 treatments with a factorial design. Substituting SoyPass into the diet did not affect average daily gain (ADG) of calves; however, calves consuming the 35% WDGS diet gained 31% more than the 20% WDGS treatment calves. Dry matter intake (DMI) and feed to gain (F:G) increased linearly in the 35% WDGS diet with the inclusion of SoyPass. In the 20% WDGS diet, DMI and F:G were maximized when SoyPass replaced 30% of the WDGS and lowest when SoyPass replaced 60% of WDGS. Therefore, SoyPass can replace up to 60% of the WDGS in forage based diets containing 20% WDGS with no adverse effects on performance by appearing to supply needed lysine

Evaluation of growth performance, carcass characteristics, and methane and CO\u3csub\u3e2\u3c/sub\u3e emissions of growing and finishing cattle raised in extensive or partial-intensive cow-calf production systems

An experiment was conducted over 2 yr to measure performance and greenhouse gas (GHG) emissions of weaned calves from two cow-calf production systems. Crossbred steers and heifers (n = 270, initial body weight (BW) = 207 kg, SD = 35) were used in a randomized complete block design, with treatments applied to the cow-calf system. Treatments were: 1) a traditional system consisting of April to June calving with smooth bromegrass pasture and grazed corn residue as forage resources (TRAD); 2) an alternative system consisting of July to September calving utilizing partial-drylot feeding, summer-planted oats, and corn residue grazing (ALT). Calves from both production systems were weaned at the same age and grown (diet NEg = 1.05 Mcal kg–1) for approximately 117 d. The calves then transitioned to a high-grain finishing diet (year 1: NEg = 1.32 Mcal kg–1; year 2: NEg = 1.39 Mcal kg–1) and fed to a targeted 1.52 cm backfat. Growth performance in the grower phase resulted in greater (P \u3c 0.01) average daily gain (1.39 vs. 1.22 ± 0.02 kg), greater gain:feed (P \u3c 0.01; 0.157 vs. 0.137 ± 0.003) for ALT calves compared to TRAD calves, However, a lower initial BW (P \u3c 0.01; 185 vs. 229 ± 4.9 kg) resulted in a lower ending BW (P \u3c 0.01; 347 vs. 371 ± 2.9 kg) for ALT calves compared to TRAD calves in spite of improved growth performance. In the finisher phase, ALT calves gained less (1.52 vs. 1.81 ± 0.218 kg; P = 0.02), were less efficient (0.139 vs. 173 ± 0.0151; P = 0.01) but exhibited similar hot carcass weights (HCW) (388 vs. 381 ± 3.8 kg; P = 0.14) compared to TRAD calves. Each pen of calves was put into a large pen-scale chamber that continuously measured carbon dioxide (CO2 ) and methane (CH4 ) for 5 d during the grower and finisher phases. The average CH4 and CO2 production per unit of feed intake was used to calculate total GHG emissions over the entire grower and finisher phase. Overall, there were no differences (P ≥ 0.17) between treatments for CH4 per day and per kilogram dry matter intake (DMI). However, ALT calves tended to produce less (P ≤ 0.10) CO2 per day and per kilogram DMI than TRAD calves. Overall, methane emissions were greater in ALT calves (110.7 vs. 92.2 ± 8.3 g CH4 kg–1 HCW; P = 0.04) than TRAD calves. The ALT calves required 27 additional days on feed to market, which resulted in more total CH4 per animal across the entire feeding period (P = 0.02) than TRAD calves. Production systems that reduce days to market to achieve similar HCW may reduce GHG emissions

Evaluation of Protein from Distillers Grains in Finishing Diets on Nutrient Digestibility

A metabolism trial was conducted to evaluate protein from modified distillers grains plus solubles (MDGS) in finishing diets on nutrient digestibility and ruminal fermentation characteristics. Isolated protein from corn was not different than MDGS for dry matter, organic matter, or neutral detergent fiber digestibility. However, steers fed MDGS tended to have lower total tract organic matter digestibility compared to corn and protein from corn. Protein had greater total tract organic matter and starch digestibility than MDGS. Protein from corn did not contribute towards the lower digestibility of MDGS. Protein is more easily digestible than the other components in distillers grains plus solubles

Evaluation of Protein from Distillers Grains in Finishing Diets on Nutrient Digestibility

A metabolism trial was conducted to evaluate protein from modified distillers grains plus solubles (MDGS) in finishing diets on nutrient digestibility and ruminal fermentation characteristics. Isolated protein from corn was not different than MDGS for dry matter, organic matter, or neutral detergent fiber digestibility. However, steers fed MDGS tended to have lower total tract organic matter digestibility compared to corn and protein from corn. Protein had greater total tract organic matter and starch digestibility than MDGS. Protein from corn did not contribute towards the lower digestibility of MDGS. Protein is more easily digestible than the other components in distillers grains plus solubles

Eff ect of Revalor- XH, Revalor- 200, and Combination Revalor- IH/Revalor- 200 on Yearling Heifer Growth Performance and Carcass Characteristics

A commercial feedlot trial tested three implant strategies (Revalor- 200 on day 0, Revalor- IH on d 0 and re- implanted with Revalor- 200 on d 56, or Revalor- XH on d 0) on growth performance and carcass characteristics of heifers fed for 138 d. Th ere were no differences observed for final body weight, dry matter intake, or average daily gain on a live basis among implant strategies. Heifers implanted with Revalor- IH/200 combination had greater carcass- adjusted final body weight and improved feed conversion compared to Revalor- 200 and Revalor- XH. Hot carcass weights, dressing percent, and LM area were improved for Revalor- IH/200 implanted heifers relative to Revalor- 200 and Revalor- XH implanted heifers. Marbling score and 12th- rib fat thickness were not different among implant treatments. Heifers implanted with Revalor- IH/200 had a shift to a lower USDA yield grade distribution compared to 200 and XH implanted heifers. Th e greater concentration of trenbolone acetate and estradiol provided by Revalor- IH/200 combination slightly improved growth and carcass performance compared to the non- coated Revalor- 200 implant and partially coated Revalor- XH implant

Evaluation of an Algal Biomass as an Ingredient in Cattle Feed

A study was conducted evaluating the effects of feeding condensed algal residue solubles (CARS; available in 2019 in Blair, NE area) to finishing cattle for 100 days. Four levels of CARS were evaluated with 5 steers and 5 heifers individually fed per level of inclusion. The diets consisted of 70% dry rolled corn with CARS displacing corn at 0, 2.5, 5, and 7.5% of dry matter. Increasing CARS inclusion resulted in a linear decrease in intake, a quadratic increase in daily gain, and a linear decrease in feed:gain. Calculations showed a linear increase in dietary net energy as CARS increased in the diet. Minimal differences in organ weights, blood chemistry, hematology, and urine were observed. Daily observations and histology results suggest no differences in cattle health due to dietary treatment. Including CARS at 5% of diet dry matter increased gain 4.2% and feed:gain 10.1% relative to a corn based finishing diet