Reliable estimation of nutrient concentrations is required to manage animal manure for protecting waters while sustaining crop production. This study was conducted to investigate sample variability and reliable nutrient analysis for several manure types and handling systems. Serial samples were collected from dairy, swine, and broiler poultry operations while manure was being loaded onto hauler...

Manure application increases pasture crop production and minimizes manure storage costs. Excess N not absorbed by pasture vegetation can leach past the root zone and into ground water. A yearlong study was conducted on grazing pastures at 2 dairy farms to monitor potential nitrate (NO3) movement from the surface through the soil profile toward ground water. Precipitation, irrigation, manure app...

Concern over nonpoint-source phosphorus (P) losses from agricultural lands to surface waters has resulted in scrutiny of factors affecting P loss potential. A rainfall simulation study was conducted to quantify the effects of alternative P sources (dairy manure, poultry manure, swine slurry, and diammonium phosphate), application methods, and initial soil P concentrations on runoff P losses fro...

Increasing feed costs and the desire to improve environmental stewardship have stimulated renewed interest in improving feed efficiency of livestock, including that of US dairy herds. For instance, USDA cost projections for corn and soybean meal suggest a 20% increase over 2010 pricing for a 16% protein mixed dairy cow ration in 2011, which may lead to a reduction in cow numbers to maintain pro...

The ability to predict manure nitrogen mineralization is essential for optimizing crop growth while preventing N losses to the environment. However, estimating mineralizable manure N is problematic because of the wide variety of organic manure N forms, as well as the lack of a rapid standardized method. Fourier-transformed infrared spectroscopy (FT-IR) is a promising technology, since it can de...

When handled separately from manures, dairy farm effluents (DE) are costly to manage because of their low nutrient content and large volume. In anticipation of using surface irrigation to lower the land application cost of DE, this projects investigated the impact, on DE characteristics, of different sources and storage systems. Milk house wastewaters were monitored on two farms using a 500 l m...

Mechanistic, predictive equations for phosphorus (P) transport in runoff from manure-applied fields constitute a critical knowledge gap for developing nonpoint-source pollution models. We derived two simple equations to describe the P release from animal manure during a rainfall event-one based on first-order P desorption kinetics and one based on second-order kinetics. The manure characteristi...

Different mixtures were digested in a single-stage, batch, mixed, laboratory scale mesophilic anaerobic digester at the Biomass Research Centre Laboratory (University of Perugia). The yield and the composition of biogas from the different substrates were evaluated and the cumulative curves were estimated. Two experimental campaigns were carried out, the first on three mixtures (chicken, pig and...

The environmental loading of steroid hormones contained in dairy wastes may cause an adverse effect on aquatic species. To better assess the potential risks of hormone contamination resulting from land application of dairy wastes, various steroid hormones were determined in a typical dairy waste disposalsystem.Quantitativemethodsusinggaschromatography/ mass spectrometry (GC/MS) were developed t...