Use of unique or non-traditional feeds: Are we revisiting old school feedlot diets?

Corn prices have been variable the past few years and generally more expensive. As a result, we have initiated a few different research programs to address these needs. Early on, grain was expensive ($5/bu or more), distillers grains (wet or modified) were relatively inexpensive as a percentage of grain price (70 to 90$50 to $70/ton). As a result, research focused on how to use more residue and distillers grains and less corn grain. Two research areas were evaluated: alkaline treatment of corn stalks and increasing use of corn silage as methods to decrease corn usage. The questions were if you decrease corn inclusion, will performance be maintained or will feed conversion get worse. Even with some depression (increase) in F:G, will cost of gain be more competitive

Managing N Inputs and the Effect on N Losses Following Excretion in Open-Dirt Feedlots in Nebraska

Feedlot nutrition will play an important role in meeting environmental challenges of beef cattle feedlots. Nutritionists are continually refining protein requirements and recently adopted a new, metabolizable protein (MP) system to more efficiently use N and allow more accurate diet formulation. Protein requirements vary by animal age and weight during the finishing period. Our hypothesis was that formulating diets with the MP system would decrease N inputs leading to decreased excretion and losses. Comparing industry average diets (13.5% CP) to phase-fed diets formulated to not exceed MP requirements decreased N inputs by 10 to 20% for calves and yearlings without affecting ADG. Decreasing inputs led to a concomitant decrease in N excretion (12-21%) and losses (15 to 33%) in open-dirt feedlot pens. Nitrogen losses are variable with time of year, with averages of 60 to 70% of excreted N lost during the summer months and 40% lost from November to May feeding periods. Protein requirements are being refined continually as more research data are collected. However, formulation to meet, but not exceed, protein requirements is an important nutritional management option for feedlots to become sustainable

Effects of Manipulating Protein and Phosphorus Nutrition of Feedlot Cattle on Nutrient Management and the Environment

Feedlot nutrition will play a role in meeting challenges such as nutrient management. Nitrogen and phosphorus are two nutrients that are currently studied in this context. One nutritional method is formulating diets not to exceed requirements for nitrogen and phosphorus. Requirements are different for calves and yearlings. The requirements also change during the finishing period. Phosphorus requirements have not been extensively studied for feedlot cattle between 270 and 600 kg. Therefore, P requirements studies were conducted to determine the P requirement of calves (265 kg) and yearlings (385 kg). The requirement was not detected with P levels as low as 0.14 (yearlings) and 0.16% (calves) of diet DM based on performance and bone ash. Compared to NRC-predicted P requirements, P intakes ranged from 76 to 190% (calves) and 71 to 162% (yearlings). In separate nutrient balance experiments, decreasing dietary P to NRC-predicted requirements (0.22 to 0.28%) did not influence gain but decreased P input by 33 to 45% and excretion by 40 to 50% compared to the industry average (0.35% P). The metabolizable protein (MP) system was recently adopted and may allow more accurate diet formulation for protein, thereby decreasing N excretion. Compared to the industry average (13.5% CP) and formulation with the CP system, using the NRC model and phase-feeding not to exceed MP requirements over the feeding period decreased N inputs by 10 to 20% for calves and yearlings without affecting ADG. Decreasing N inputs led to a concomitant decrease in N excretion (12 to 21%) and volatilization (15 to 33%) in open-dirt feedlot pens. Nitrogen losses are variable with time of year, with averages of 60 to 70% of excreted N lost during the summer months and 40% lost from November to May feeding periods. Protein requirements are continually being refined as more research data are collected. However, formulation to meet and not exceed protein requirements and removal of P supplements are important nutritional management options to help feedlots become more environmentally sustainable

Effect of Urea and Distillers Inclusion in Dry- Rolled Corn Based Diets on Heifer Performance and Carcass Characteristics

Crossbred heifers (n=96, BW = 810 ± 20) were utilized to evaluate the effects of increasing wet distillers grains plus solubles and urea inclusion in a dry rolled corn based finishing diet on performance and carcass characteristics. Heifers were individually fed using a calan gate system with a 2 × 2 factorial arrangement of treatments. Factors included distillers inclusion at either 10 or 20% of diet DM and urea inclusion at either 0.2 or 1.4% of diet DM. Th ere was no difference for final body weight, average daily gain, and feed conversion on a live or carcass adjusted basis for either urea or distillers inclusion in the diet. Dry matter intake was reduced with increased urea inclusion; however, distillers inclusion did not influence intake. Added distillers and urea in the diet had minimal impact on performance suggesting supplemental urea in a dry rolled corn based finishing diets is of minimal benefit when feeding at least 10% distillers grains

Effects of Manipulating Protein and Phosphorus Nutrition of Feedlot Cattle on Nutrient Management and the Environment

Feedlot nutrition will play a role in meeting challenges such as nutrient management. Nitrogen and phosphorus are two nutrients that are currently studied in this context. One nutritional method is formulating diets not to exceed requirements for nitrogen and phosphorus. Requirements are different for calves and yearlings. The requirements also change during the finishing period. Phosphorus requirements have not been extensively studied for feedlot cattle between 270 and 600 kg. Therefore, P requirements studies were conducted to determine the P requirement of calves (265 kg) and yearlings (385 kg). The requirement was not detected with P levels as low as 0.14 (yearlings) and 0.16% (calves) of diet DM based on performance and bone ash. Compared to NRC-predicted P requirements, P intakes ranged from 76 to 190% (calves) and 71 to 162% (yearlings). In separate nutrient balance experiments, decreasing dietary P to NRC-predicted requirements (0.22 to 0.28%) did not influence gain but decreased P input by 33 to 45% and excretion by 40 to 50% compared to the industry average (0.35% P). The metabolizable protein (MP) system was recently adopted and may allow more accurate diet formulation for protein, thereby decreasing N excretion. Compared to the industry average (13.5% CP) and formulation with the CP system, using the NRC model and phase-feeding not to exceed MP requirements over the feeding period decreased N inputs by 10 to 20% for calves and yearlings without affecting ADG. Decreasing N inputs led to a concomitant decrease in N excretion (12 to 21%) and volatilization (15 to 33%) in open-dirt feedlot pens. Nitrogen losses are variable with time of year, with averages of 60 to 70% of excreted N lost during the summer months and 40% lost from November to May feeding periods. Protein requirements are continually being refined as more research data are collected. However, formulation to meet and not exceed protein requirements and removal of P supplements are important nutritional management options to help feedlots become more environmentally sustainable

Evaluation of Masters Choice Corn Silage on Growing Steer Performance

A growing study evaluated three corn silage hybrids on growing steer performance. Th e three hybrids were: a conventional hybrid- Farm Choice (CON) commonly grown in Eastern Nebraska which served as the control, Masters Choice hybrids MCT6365 RIB (MC1) selected to improve fi ber and starch digestion and MCT6733 GT3000 (MC2) that has been selected to improve fi ber digestion in cattle. Relative to CON, feeding hybrid MC1 resulted in similar DMI, but numerically increased ADG which significantly improved F:G compared to CON. Feeding MC2 led to greater DMI, similar ADG, and poorer (greater) F:G compared to CON. Feeding Masters Choice hybrid MCT6365 RIB (MC1) corn silage at 80% of the diet DM likely improved digestion and energy availability to the steers, which allowed greater ADG and improved F:G, while the opposite was true for MC2. Differences in hybrids exist when fed to growing cattle at 80% of the diet

Individual Beef Cattle Identification Using Muzzle Images and Deep Learning Techniques

The ability to identify individual animals has gained great interest in beef feedlots to allow for animal tracking and all applications for precision management of individuals. This study assessed the feasibility and performance of a total of 59 deep learning models in identifying individual cattle with muzzle images. The best identification accuracy was 98.7%, and the fastest processing speed was 28.3 ms/image. A dataset containing 268 US feedlot cattle and 4923 muzzle images was published along with this article. This study demonstrates the great potential of using deep learning techniques to identify individual cattle using muzzle images and to support precision beef cattle management. Individual feedlot beef cattle identification represents a critical component in cattle traceability in the supply food chain. It also provides insights into tracking disease trajectories, ascertaining ownership, and managing cattle production and distribution. Animal biometric solutions, e.g., identifying cattle muzzle patterns (unique features comparable to human fingerprints), may offer noninvasive and unique methods for cattle identification and tracking, but need validation with advancement in machine learning modeling. The objectives of this research were to (1) collect and publish a high-quality dataset for beef cattle muzzle images, and (2) evaluate and benchmark the performance of recognizing individual beef cattle with a variety of deep learning models. A total of 4923 muzzle images for 268 US feedlot finishing cattle (\u3e12 images per animal on average) were taken with a mirrorless digital camera and processed to form the dataset. A total of 59 deep learning image classification models were comparatively evaluated for identifying individual cattle. The best accuracy for identifying the 268 cattle was 98.7%, and the fastest processing speed was 28.3 ms/image. Weighted cross-entropy loss function and data augmentation can increase the identification accuracy of individual cattle with fewer muzzle images for model development. In conclusion, this study demonstrates the great potential of deep learning applications for individual cattle identification and is favorable for precision livestock management. Scholars are encouraged to utilize the published dataset to develop better models tailored for the beef cattle industry

Beef Fatty Acid Profiles from Steers Finished with De-oiled Dry Distillers Grains Plus Solubles vs. a Corn- Based Diet

A total of 128 steers were fed one of two finishing diets: 50% de-oiled dry distillers grains plus solubles (DDGS) or a corn- based control diet. Carcasses (n = 48) were selected to evaluate the effect of diet on the fatty acid profile of strip loin steaks. Th e C15:0, C16:1, C17:0, and C17:1 were greater for beef from steers finished on the corn- based control diet while the C18:1T, C18:2, C20:3ω6, total trans, ω6 and polyunsaturated fatty acids (PUFA) were greater in beef from cattle finished on 50% de-oiled DDGS. These findings confirm that feeding distillers grains plus solubles (be it wet or dry) increases the amount of PUFA’s in meat

Evaluation of the Water Footprint of Beef Cattle Production in Nebraska

Data were compiled on feed usage to model the amount of water needed to produce beef in typical Nebraska production systems. Production systems where cows were wintered on corn residue utilized 18% less water than systems utilizing native range as a wintering source, because of water allocations. Therefore, the water footprint (gallons of water required to produce one pound of boneless meat) was decreased by 18%. In addition, increasing the dietary inclusion of distillers grains from 0% to 40% decreased the water footprint in the finishing phase by 29%, again based on water allocation. Utilizing corn residue and distillers grains in Nebraska beef cattle systems decreases the overall water footprint of production. Additionally, the water footprint of the systems analyzed was 80% green water as rain, minimizing the environmental impact of beef production on freshwater use and ecological water balance

Evaluation of the effects of wood-sourced biochar as a feedlot pen surface amendment on manure nutrient capture

Feedstuffs utilized in U.S. feedlot finishing rations incorporate high concentrations of N and P, with less than 15% of fed N and P retained by the animal. The remaining N and P are excreted in the manure, where the opportunity for manure N loss via ammonia (NH3) volatilization from the feedlot pen surface is a risk to the environment and lowers the value of manure as a fertilizer. Two nutrient mass balance experiments were conducted during the winter and summer seasons to evaluate the effects of spreading unprocessed Eastern red cedar biochar onto the feedlot pen surface on manure nutrient capture and cattle performance. A 186-d feedlot fnishing experiment was conducted from December to June (WINTER) and a subsequent 153-d fnishing experiment was conducted from June to November (SUMMER). The WINTER experiment evaluated three treatments (5 pens per treatment; 10 steers per pen), including biochar spread on pen surface during the feeding period (1.40 kg biochar/ m2 ; 17.6 m2 /steer soil surface of the pen), hydrated lime spread on pen surface at end of feeding period (1.75 kg/m2 ) and control (no treatment applied). The SUMMER experiment evaluated biochar treatment (1.40 kg biochar/m2 ; 5 pens per treatment; 8 steers per pen; and 22 m2 /steer soil surface of the pen) against control. There were no differences in N and P intake, retention, or excretion (P ≥ 0.38) between WINTER treatments. Steer performance (P ≥ 0.10) and carcass characteristics (P ≥ 0.50) were not impacted by pen treatment in WINTER. Nitrogen and P intake and excretion (P ≥ 0.35) were not different between treatments in SUMMER and retention of N and P was signifcantly greater for the biochar treatment (P ≤0.04) due to greater ADG (P = 0.05). There was no difference in DMI (P = 0.48) in SUMMER, steers on biochar pen treatment had heavier HCW (P = 0.05) and greater ADG, resulting in a tendency for greater feed effciency (P = 0.08). In both experiments, biochar addition to the pen surface tended (P = 0.07) to increase manure N as a percent of manure DM, but this increase in N concentration did not impact kg of N removed from the feedlot pens (P ≥ 0.15) or N losses (P ≥ 0.68). The addition of red cedar biochar to the feedlot pen surface did not increase manure nutrient capture of N or P and did not reduce N losses associated with soil-based feedlot pens