Location: Dairy Forage Research
Project Number: 5090-31000-027-000-D
Project Type: In-House Appropriated
Start Date: Aug 3, 2022
End Date: Aug 2, 2027
Objective:
Objective 1: Develop and evaluate dietary feed formulation strategies that increase the utilization of conventional feeds/forages and alternative feeds/forages that reduce competition with human food consumption, increase milk production, enhance nutrient use efficiency, and reduce greenhouse gas emissions in dairy production systems.
Sub-objective 1.A: Evaluate effects of forage type, amount, and quality on animal performance, nutrient digestibility, and feed conversion efficiency.
Sub-objective 1.B: Evaluate effects of alternative/byproducts feeds that replace or reduce traditional concentrate feeds in the diet on animal performance, nutrient digestibility, feed conversion efficiency, and gas emissions.
Sub-objective 1.C: Evaluate the inclusion of feed additives to forage-based diets on animal performance, nutrient digestibility, feed conversion efficiency, and gas emissions.
Objective 2: Develop and evaluate dietary feed formulation strategies using partial mixed rations (PMR), based on forage base, nutrient composition and feed physical form, to enhance individual animal feed efficiency and reduce environmental impact of dairy farms.
Sub-objective 2.A: Evaluate individual animal energetic usage and efficiency based on plane of nutrition and management that can impact feeding in a Partial Mixed Ration (PMR) system.
Sub-objective 2.B: Evaluate effects of one versus two feeds, nutrient composition, and feed forms on feed efficiency, precision data collected, environmental impacts and measurements within and between individual or small groups of cows using a PMR.
Objective 3: Evaluate the effects of forage/feed type and soil health management interventions on farm carbon balance, nutrient losses, and milk productivity and quality in dairy production systems.
Sub-objective 3.A: Evaluate soil health factors for their effects on forage productivity and nutritive value, to inform management practices and forage selection that will improve milk yield and quality.
Approach:
Objective 1. A series of dairy cattle studies will be conducted to evaluate the effect of forage type, forage amount, and forage quality on animal performance, nutrient digestibility, and feed conversion efficiency. In addition, alternative forages and byproduct feedstuffs will be evaluated as replacements for traditional feedstuffs used in dairy cattle diets. Inclusion of feed additives to forage-based diets will be evaluated for animal performance, nutrient digestibility, feed conversion efficiency, and gas emissions. We will collect production measurements, rumen samples, feces, urine and gaseous emissions to determine the effects of altering fiber digestibility on ruminal fermentation, lactation performance, and environmental output.
Objective 2. A series of dairy cattle studies will be conducted to evaluate dietary feed formulation strategies using partial mixed rations (PMR), based on forage base, nutrient composition and feed physical form, to enhance individual animal feed efficiency and reduce environmental impact of dairy farms. In the first study, calves born to either nutrient-restricted dams and nutrient-sufficient dams will be followed through to adulthood to determine whether nutrient-restricted heifers with emit be less productive and have greater environmental impact due to reduced productive efficiency relative to their herdmates. In a second study, cows will be evaluated on how milking permissions in automatic milking systems impact animal metabolism. In a third study, the effects on a one or two feed system, nutrient composition and feed forms of cows fed a partial mixed rations will be evaluated for production measures, feed efficiency, and environmental impacts.
Objective 3. Two exploratory field investigations and a greenhouse trial are planned to evaluate the effects of forage/feed type and soil health management interventions on farm carbon balance, nutrient losses, and milk productivity and quality in dairy production systems. Field investigations will investigate fields with different management and land cover differences to determine whether specific soil health indicators are positively correlated with forage nutritive quality or digestibility. A greenhouse trial will be conducted implementing a factorial arrangement of treatments with the following factors: soil source, crop type (corn silage, alfalfa) and water availability (optimal vs 50% optimal water availability). 4 x 2 x 2 factorial design with the following factors: soil source, crop type (corn silage, alfalfa) and water availability (optimal vs 50% optimal water availability). Optimal water availability will be determined based on the field capacity of soils, with 50% of field capacity for the drought treatment. This trial will 1) determine the effects of soil health indicators on forage quality and productivity; 2) Compare input costs for soil source x crop type for an assessment of production efficiency; and 3) Compare carbon assimilation and water use efficiency of crops under varied soil conditions.
