Browsing by Subject "Feedlot"

Now showing 1 - 4 of 4
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    Backgrounding methods for growing beef cattle and strategies for incorporating alternative feedstuffs into diets of finishing beef cattle.
    (2011-05) Kelzer, Jolene Madonna
    Volatile commodity and cattle markets present challenges for profitable beef production. Four experiments were conducted to evaluate backgrounding methods for growing cattle and utilizing alternative feedstuffs in finishing diets to improve feedlot performance and efficiency. Experiment 1 evaluated the effectiveness of grazing stockpiled and swathed annual ryegrass as backgrounding systems on forage quality and beef stocker cattle performance. Results of experiment 1 suggest grazing stockpiled and swathed annual ryegrass may be viable backgrounding systems; however, forage maturity and winter weather conditions may reduce forage quality and accessibility to levels that can limit stocker cattle performance. Experiment 2 evaluated the effects of reproductive status (spayed vs. intact heifers supplemented with melengestrol acetate) and terminal implant strategy (moderate vs. aggressive) on beef feedlot heifer performance during backgrounding and finishing phases and on carcass characteristics. Results of experiment 2 suggest intact heifers supplemented with melengestrol acetate had greater performance during backgrounding; however, use of moderate or aggressive terminal implant strategies may allow similar performance during finishing and comparable carcass characteristics between spayed and intact beef feedlot heifers. Experiment 3 evaluated the effects of partially replacing dry-rolled corn in traditional corn-based finishing diets with either 35% conventional dried distillers grains plus solubles or 35% high protein dried distillers grains on beef steer feedlot performance and carcass characteristics. Results of experiment 3 suggest that although overall feed intake tended to be reduced, high protein dried distillers grains may successfully replace conventional dried distillers grains plus solubles or up to 35% of dry-rolled corn in finishing beef cattle diets. Experiment 4 evaluated effects of supplemental manganese in high-sulfur feedlot diets containing dried distillers grains plus solubles on in vitro and in vivo ruminal fermentation and hydrogen sulfide gas production. In vitro results of experiment 4 suggest that 1,000 ppm manganese in high-sulfur diets appeared to release less total hydrogen sulfide gas than 0 or 500 ppm manganese; whereas in vivo results suggest beef steers consuming 1,000 ppm manganese may have a less acidic ruminal environment prior to feeding to result in a tendency for reduced average ruminal hydrogen sulfide concentration.
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    Effect of manipulation of growth and fermentation patterns on nutrient availability and performance of feedlot cattle
    (2019-08) Larson, Haley
    Alteration of ruminal environment by nutritional strategy presents opportunities for manipulating beef cattle growth. Changing fermentation patterns by altering feed type can impact both the composition and rate of gain in beef cattle. Three experiments were conducted to examine the effect of manipulation of growth and fermentation patterns on nutrient availability and performance of feedlot cattle. Experiment 1 studied the impact of ruminal environment on the passage of omega-3 fatty acids through the rumen of grass-fed verses grain-fed cattle. Omasal samples were collected from steers fed either fresh green chop, a high grain diet supplemented with flaxseed oil, or a high grain diet supplemented with corn oil. Regardless of diet, fatty acids with the greatest number of unsaturated bonds found in the highest abundance were transformed preferentially. Despite no differences (P = 0.88) in omega-3 transformation across treatments, grain-fed cattle with a flaxseed oil supplement demonstrated the greatest (P < 0.01) g of omega-3 fatty acid flow escaping biohydrogenation due to an increase in intake of dietary omega-3 fatty acids. Experiment 2 evaluated how utilization of bio-fuel coproducts impacts rumen environment and fatty acid profile at end point of fermentation. Omasal samples were collected from steers fed a steam flaked corn (SFC) basal diet with a portion of corn replaced by distillers grains (DGS) (40%), crude glycerin (GLY) (10%) or both. Total unsaturated fatty acids concentration in digesta were not different (P = 0.43) for the main effect of GLY, which indicates GLY is an effective alternative to corn when provided at the dietary concentrations evaluated in this study. The decrease (P < 0.01) in unsaturated fatty acids in digesta for main effect of DGS may be beneficial for shelf life stability of meat. Experiment 3 used a meta-analysis approach to examine how nutritional strategy and performance during a post-weaning growing phase can be used to predict finishing performance and carcass characteristics. When examining feedlot and carcass performance attributes by growing strategy factors, like ADGgrowing, DOFgrowing, and initial BWfinishing, interacted to create the most optimal compensatory gain response. Optimal combinations of DOFgrowing and initial BWgrowing differed between performance characteristics (Table 4.6) but as an average across dressing percent, LMA, Final BWfinishing, and HCW it was identified that maximized performance occurred when cattle began the growing phase around 240 kg.
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    Evaluation of snowmelt for implementation into the Minnesota Feedlot Annualized Runoff Model
    (2013-10) Remer, Allison Salome
    The Minnesota Feedlot Annualized Runoff Model (MinnFARM) was designed by University of Minnesota, the University of Minnesota Extension Office and the Minnesota Pollution Control Agency (MPCA) to evaluate pollution potential to waters of the state created by surface runoff leaving an animal feedlot. State and Federal Agencies use MinnFarm results to determine compliance and rank feedlots on a standardized scale. The goal of this study is to improve the snowmelt portion of the MinnFARM model utilizing obtainable data to account for regional variations that exist throughout the Minnesota. Refinement of the snowmelt portion of the MinnFARM model is required to increase the accuracy of the seasonal aspect of the potential nutrient load leaving a livestock open lot. Observed daily snowmelt depths were computed from the daily difference in snow-water-equivalent data provided by the National Weather Service for Marshall, St. Cloud and Rushford, MN. Corresponding climate data sets were obtained for these three sites. The reliability of the observed snowmelt depths was evaluated by examining the consistency in observed depths for large events measured at Marshall. The accuracy of the Degree-Day method, Restricted-Degree-Day method, Statistical Energy-Balance Approach and Process Based Energy-Balance Approach were compared in this study. The Restricted-Degree-Day method had the strongest correlation when compared the observed snowmelt data set.
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    Influence Of Corn Crop Harvest Endpoint On Feedlot Performance, Beef Quality And Sensory Traits, And Return To Corn Land
    (2020-04) Johnson, Tyler
    Forty-nine Charolais x Red Angus steers (initial average BW = 536 kg) were fed individually in a Calan-Broadbent feeding system to evaluate performance and meat quality characteristics and interactions resulting from performance and crop yield when corn is harvested as either silage (SIL), earlage (EAR), high-moisture corn (HMC), or dry corn (DRC). Steers were randomly allocated to 1 of 4 dietary treatments where SIL, EAR, HMC, or DRC constituted 75% of diet DM. The remaining of SIL, EAR, HMC and DRC diets contained 11% haylage (0% for SIL), 10% modified wet corn distillers grains (MDGS), 4% liquid supplement with Rumensin (SUPP) and 11% DRC (SIL only). Gross return (gross $/hd) was determined as dollars remaining after subtracting non-corn crop expenses (cattle purchase, veterinary medicine, yardage, bedding and purchased feed ingredients) from gross cattle sale. Value of each corn crop endpoint was determined from corn grain worth ($/56 lb) and its relationship to corn grain content in SIL, EAR, and HMC crops. This value was compared to SIL, EAR, HMC worth determined by ANOVA (crop equivalent $/bu). Value of each corn crop endpoint was also determined by dividing gross return (gross $/hd) by hectares used to raise crop. The former method is used to determine corn crop endpoint worth for a feeder that purchases crops (owns no land) and the latter is used to determine corn crop endpoint worth for a feeder who owns corn land. Net return to corn hectares dedicated to cattle feeding during the last 18 years was 6.2 times greater than that realized through marketing corn through a local elevator. Cattle fed HMC had the lowest (P ≤ 0.05) DMI (dry matter intake). Cattle fed DRC had greater (P < 0.05) ADG (average daily gain) than cattle fed the other corn crops. Cattle fed HMC had greater ADG (P < 0.05) than those fed SIL. No difference between cattle fed DRC or HMC was observed for feed conversion but feeding either led to greater (P < 0.05) feed conversion than SIL or EAR. Final BW (body weight) and HCW (hot carcass weight) were greatest for DRC (P < 0.05), intermediate (P < 0.05) for HMC and lowest (P < 0.05) for EAR and SIL. There was a tendency (P = 0.08) for treatment effect on fat thickness wherein cattle fed DRC or HMC tended to have greater fat thickness than those fed SIL. No treatment differences were found for REA (ribeye area) or marbling. Sensory panel evaluation of loin steaks demonstrated that steaks from steers fed either SIL or EAR were juicier (P > 0.05) than those fed HMC and that bologna samples from steers fed HMC were toughest and least juicy. There was no effect observed for equivalent value of corn crop ($/bu). Harvesting corn as either SIL, EAR, HMC or DRC had no impact (P > 0.05) on crop worth (gross $ return/hectare). Despite performance differences, all harvest end points dedicated to cattle feeding result in greater gross return to corn land than marketing corn through local channels. This permits greater flexibility in corn harvest end point decisions for cattle feeders.