Managing Feed Deliveries And Optimizing Inclusion Of Non-Antibiotic Feed Additives And Supplemental Sugar In A Cattle Feeding Program

University of Minnesota M.S. thesis. July 2020. Major: Animal Sciences. Advisor: Alfredo DiCostanzo. 1 computer file (PDF); viii, 32 pages.Feedlot management strategies are ever changing. Consumer perspectives, commodity market fluctuations, location, weather and demand of beef are only a few aspects that drive feedlot manager’s management decisions. Recent consumer push back towards the use of antibiotics in the cattle sold for beef has resulted in industry and academia to develop non-antibiotic alternatives to supplement calves during the receiving period. Therefore, a 49 d study was conducted to understand the effect of blended DFM, prebiotics and probiotics on receiving cattle. By day 7, cattle fed either additive had greater ADG, improved feed efficiency which continued throughout the 49 d study ultimately resulting in greater final BW compared to cattle not supplemented a nonantibiotic feed additive. In addition to improved performance parameters, health of supplemented cattle was also improved over the 49 d study in terms of decreased morbidity. Market fluctuations and increase in HCW has also directed cow/calf and feedlot producers to grow cattle prior to feeding a high concentrate diet. However, due to the location of some of these producers being primarily in areas of high forage production and pasture land, at times corn availability can be scarce and expensive requiring the need for an alternative energy source. A 70 d study was conducted in an effort to determine the optimum sugar inclusion, in the form of cane molasses, in a high forage backgrounding diet. Results from this study revealed replacing up to 10.5% of starch with sugar led to no adverse effects on intake or growth performance and energy content, and this inclusion was comparative to that of corn grain. A management strategy that continues to challenge feeders across the country is controlling variation in DMI. However, challenges in measuring variation in intake are often due to the fact that intake is determined as feed delivered on a pen basis. A considerable amount of research has been completed to understand performance responses to fluctuations feed delivered and frequency of delivery. Due to quantity of precipitation in a year in the Midwest, changes in DM of ingredients may also fluctuate DMI of cattle fed high concentrate diets. For that reason, an 84 day study was completed to understand whether as-fed dietary composition adjustments are necessary as feed ingredient DM content changes and to validate on-farm feed ingredient dry matter determination methods. Results of this study revealed adjusting as-fed dietary composition due to changes in DM content of feed ingredients daily resulted in no benefit over adjusting as-fed dietary composition every 28 d. Using a microwave and Koster tester to determine hay and corn silage DM, respectively, resulted in DM that were similar to those using laboratory procedures. However, DM estimated of high moisture corn using a Koster tester were different than DM determined using laboratory procedures