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

Determinants of Profit Variability in Calf-Fed and Yearling Production Systems

Factors that were determinants of profit variability in calf-fed and yearling beef production systems were identified and ranked. The analysis indicated cattle prices have the greatest influence on profit variation for both systems and on all backgrounding and finishing phases of the yearling system. Prices of feedstuffs (i.e., corn prices, wet corn gluten feed prices, and pasture and cornstalk rental rates) were the next most important factors explaining profit risk. Cattle performance variables and interest rates had the smallest impact on profit variation

Wheat Straw, Distillers Grains, and Beet Pulp for Late Gestation Beef Cows

The feeding value of a mixture of 30:70 wet distillers grains:wheat straw or 20:20:60 wet distillers grains:beet pulp:wheat straw (DM) for late gestation beef cows was estimated. In Experiment 1, cows limit fed distillers grains and wheat straw gained as much weight and body condition as cows limit fed alfalfa hay. In Experiment 2, cows fed wet distillers grains and wheat straw or wet distillers grains, beet pulp, and wheat straw gained more weight and improved body condition compared with cows fed alfalfa hay. The results of these experiments indicate cows in late gestation will maintain body condition when limit fed by-products and crop residues to meet their energy requirements

Wheat Straw, Distillers Grains, and Beet Pulp for Late Gestation Beef Cows

The feeding value of a mixture of 30:70 wet distillers grains:wheat straw or 20:20:60 wet distillers grains:beet pulp:wheat straw (DM) for late gestation beef cows was estimated. In Experiment 1, cows limit fed distillers grains and wheat straw gained as much weight and body condition as cows limit fed alfalfa hay. In Experiment 2, cows fed wet distillers grains and wheat straw or wet distillers grains, beet pulp, and wheat straw gained more weight and improved body condition compared with cows fed alfalfa hay. The results of these experiments indicate cows in late gestation will maintain body condition when limit fed by-products and crop residues to meet their energy requirements

Determinants of Profit Variability in Calf-Fed and Yearling Production Systems

Factors that were determinants of profit variability in calf-fed and yearling beef production systems were identified and ranked. The analysis indicated cattle prices have the greatest influence on profit variation for both systems and on all backgrounding and finishing phases of the yearling system. Prices of feedstuffs (i.e., corn prices, wet corn gluten feed prices, and pasture and cornstalk rental rates) were the next most important factors explaining profit risk. Cattle performance variables and interest rates had the smallest impact on profit variation

Cysteine from Feather Meal And Sulfur Amino Acid Requirements for Growing Steers

Ninety individually fed steers were used to determine how cysteine from feather meal could replace dietary methionine in meeting their requirements for sulfur amino acids. Treatment proteins included blood meal, blood meal plus incremental levels of feather meal or blood meal plus incremental levels of rumen-protected methionine. Addition of sulfur amino acids to blood meal from feather meal or rumen-protected methionine improved average daily gain (P \u3c .05). Rumen-protected methionine elicited a greater gain response than feather meal (P \u3c .05). Feather meal can provide some of the sulfur amino acids lacking in blood meal. However, additional methionine may further improve performance

G84-693 Protein Levels for Growing and Finishing Cattle

This NebGuide describes the use of nonprotein nitrogen and bypass protein sources to fulfill the protein requirements of growing and finishing steers, heifers and bulls. Protein supplementation can be an expensive feed cost for cattle producers. Through the use of nonprotein nitrogen (NPN) and bypass protein sources, however, these costs can be reduced. Bypass protein is the protein that escapes breakdown in the rumen and passes as is into the small intestine where it is digested and absorbed. Because NPN sources are usually the most economical sources of supplemental nitrogen, NPN should be used whenever possible. The potential for using NPN depends on the ability of the rumen microorganisms to synthesize protein, the bypass protein supplied by ration ingredients, and the protein requirement of the animal

Effect of Corn Stalk Grazing and Baling on Cattle Performance and Irrigation Needs

The effects of removing corn residue by grazing and baling on continuous corn production were investigated. Initial data showed a trend toward keeping more water in the soil in the treatment with the most residue left on the field (no grazing or baling), but there was no effect of either grazing or baling on subsequent corn yield. Water conservation resulting from maintaining residue on the field may help reduce pumping costs or increase yields when water is limited. However, this benefit is likely to be outweighed by feed cost savings or grazing rental income, and good cow performance

Effect of Micro-Aid\u3csup\u3e®\u3c/sup\u3e Supplementation on Nitrogen Losses from Manure

A 2x2 factorial designed experiment was used to study the effects of Micro-Aid and time on OM and N losses from manure, in a simulated feedlot pen setting. Manure was collected from cattle on a common diet, except for the addition of 1 g Micro-Aid /steer daily. Losses of OM were greater at 60 d than 30 d, and greater for control than Micro-Aid. Nitrogen losses at d 30 were similar between treatments but control pans had greater N losses at d 60. Feeding Micro-Aid to cattle may inhibit N volatilization from manure, enhancing the fertilizer value of manure

Effect of Crude Glycerin Concentration on Growing Steer Performance in Forage Diets

The effect of increasing crude glycerin concentration was evaluated in a 91- d growing trial utilizing 60 steers. Crude glycerin was included at 0, 4, 8, and 12% of dietary DM in diets consisting of 50% wheat straw; 22.9- 37.0% wet corn bran, and 8.0- 10.1% soybean meal. Crude glycerin replaced wet corn bran and soybean meal was added to maintain dietary CP. Steer ending BW was not different among treatments. Th ere was a quadratic increase in DMI from 0 to 8% crude glycerin and subsequent decrease at 12%. Th ere was no difference in ADG or feed efficiency among crude glycerin concentrations. Therefore, crude glycerin appears to have an energy value slightly less than wet corn bran in a forage- based diet