Using Extension Phosphorus Uptake Research to Improve Idaho\u27s Nutrient Management Planning Program

Irrigated silage corn is the main crop used for P removal in southern Idaho; however, little is known about the actual amounts of P removed under southern Idaho growing conditions. The study surveyed P removal by irrigated silage corn in primarily manured southern Idaho fields and wide-ranging soil test P. Whole plant corn tissue P concentrations ranged from 0.116 to 0.307% total P and averaged 0.208%—lower than Natural Resources Conservation Service (NRCS) estimates used prior to 2007 (0.26%P) but higher than estimates used since 2007 (0.185%). The study was used to update the OnePlan.org© Nutrient Management planning online program

Phosphorus Removal by Silage Corn in Southern Idaho

Corn silage is the predominant crop in Idaho used for recovering phosphorus (P) that has accumulated in soils from dairy manure applications. However, little is known about how much P and other nutrients are being recov- ered under Idaho conditions. The objective of the study is to estimate P removal by irrigated corn silage crops cultivated throughout southern Idaho with variable soil test P concentrations, and to identify effects of increasing soil test P on tissue concentrations of P and on plant P uptake. Forty-two different corn silage fields in 2008 and 2009 were selected throughout southern Idaho for soil and whole plant sampling at harvest. Soils were ana- lyzed for Olsen P, plant tissue was measured for total P content, and dry and wet yields were calculated based on field weights and drying of plant tissue

Chemical composition, antioxidant, and antimicrobial activities of Leaves of Ajuga iva

The main objective of this research was to study the biological characteristics in terms of antioxidant and antimicrobial activities of Ajuga iva and determine the best analytical and extraction methods applicable to this specie and studied compounds. A short screening of its nutritional value in terms of chemical composition is also included. A. iva leaves were analyzed for crude protein (CP), cell wall [neutral detergent fiber (NDF), acid detergent fiber (ADF), and acid detergent lignin (ADL)], minerals, fatty acids, essential oils, and phenolic compounds. Mature aerial parts of A. iva were randomly collected during the Spring season from Mograne-Zaghouan, Tunisia. Leaves of A. iva contained 13.4 ± 0.4% CP, 26.3 ± 0.35% NDF, 20.2 ± 0.42% ADF, and 5.13 ± 0.21% ADL. Mineral content (13.0 ± 0.45%) was mainly composed of potassium (4.5% g DM) and magnesium (4.25% DM). Leaves of A. iva had linolenic (26.29 ± 0.760%) and linoleic (37.66 ± 2.35%) acids as the main components of the acid profile. Thymol was found to be the most dominant (23.43%) essential oil, followed by 4-vinylguaiacol (14.27%) and linalool (13.66%). HPLC-PDA-ESI-MS/MS analysis pointed out the presence of phytoecdysteroids. Phenolic acids and flavonoids, such as glycosylated derivatives of naringenin, eriodyctiol, and apigenin, were detected in the methanol extract of A. iva leaves. Our results underline the importance of choosing proper extraction methods and solvents to extract and characterize the described compounds profile of A. iva leaves. Results also show A. iva leaves as a potential source of functional ingredients with beneficial health-promoting properties. Overall, leaves of A. iva have low biological activities (antioxidant and antimicrobial activities) with a chemical composition suitable as a feed for ruminants in rangeland pasture. It also has low-grade antibacterial or medicinal characteristics when fed to ruminants

Using extension phosphorus uptake research to improve Idaho's nutrient management planning program.

Irrigated silage corn is the main crop used for phosphorus removal; however little is known about the actual amounts of phosphorus removed under southern Idaho growing conditions. The purpose of this study was to survey phosphorus removal by irrigated corn grown for silage in southern Idaho under variable soil test phosphorus concentrations. In this survey whole plant corn tissue phosphorus concentrations ranged from 0.116 to 0.307% total phosphorus and averaged 0.208%, which is lower than Natural Resources Conservation Services estimates used prior to 2007 (0.26% phosphorus) but higher than estimates used since 2007 (0.185%). The study was used by NRCS to update nutrient management planning software used by planners in Idaho

Nutritive Value of Ajuga iva as a Pastoral Plant for Ruminants: Plant Phytochemicals and In Vitro Gas Production and Digestibility

This study aims to evaluate the nutritive value of Ajuga iva (A. iva) harvested from three distinct altitude regions in Tunisia (Dougga, Mograne, and Nabeul). The chemical composition, phenolic concentration, gas production, and in vitro dry matter (DM) digestibility were determined. The highest concentrations of neutral detergent fiber (NDF) and acid detergent fiber (ADF) were for A. iva cultivated in Nabeul. In contrast, the highest crude protein (CP) concentration was observed in that cultivated in Mograne, and the lowest (p < 0.01) CP concentration was noted in that cultivated in Dougga. Additionally, the cultivation regions affected the concentrations of free-radical scavenging activity, total flavonoids, and total polyphenols (p < 0.01). The highest free-radical scavenging activity was observed with A. iva cultivated in Dougga and Mograne. The highest (p < 0.05) gas production rate and lag time were observed in A. iva cultivated in Mograne and Nabeul regions. DM digestibility differed between regions and methods of determination. The highest (p < 0.01) DM degradability, determined by the method of Tilley and Terry and the method of Van Soest et al., was for A. iva cultivated in Mograne and Dougga, while the lowest (p < 0.01) value was recorded for that cultivated in the Nabeul region. Likewise, metabolizable energy (ME) and protein digestibility values were higher for A. iva collected from Mograne region than that collected from the other sampling areas. In conclusion, the nutritive value of A. iva differed between regions. Therefore, care should be taken when developing recommendations for using A. iva in an entire region. Season- and region-specific feeding strategies for feeding A. iva are recommended

Effect of Exogenous Fibrolytic Enzymes Supplementation or Functional Feed Additives on In Vitro Ruminal Fermentation of Chemically Pre-Treated Sunflower Heads

peer reviewedThis study aims to provide possible utilization of sunflower head byproduct (SFH) as a feedstuff by implementing chemical pretreatments (4% sodium hydroxide (SFHNaOH) or 4% urea (SFHurea) and supplementation with either exogenous fibrolytic enzymes (EFE) or functional feed additive (FFA). The experimental EFE was a complex (1:1, v/v) of two enzyme products with high activity of β-1,3-1,4-glucanase and endo-1,4-β-D-xylanase and applied at 0 (SFHout), 1, 2, 5, and 10 µL/ gdry matter, while FFA was a fermentation byproduct rich in cellulase and xylanase activities, applied at 0 (SFHout), 0.5, 1, 2, and 4 mg/g DM. SFHurea had the highest (p < 0.05) crude protein (CP) content compared to other SFH substrates. Linear enhancements (p < 0.05) in kinetics of gas production (GP), metabolizable energy (ME), organic matter digestibility (OMD) and total short-chain fatty acids (SCFAs) concentrations were observed for all SFH substrates supplemented with EFE. The SFHout had the highest (p < 0.05) potential GP, maximum rate (Rmax) of GP, ME, OMD and SCFAs. Supplementation of EFE was more pronounced than FFA in affecting the kinetic parameters of in vitro GP for all SFH substrates. SFHout supplemented with EFE seems to be the most promising substrate to enhance microbial fermentation in vitro

Comparison of Ambient Ammonia Measurement Techniques from Dairy Area Sources

Previous studies of ag-related NH3 concentrations and/or emissions have used a variety of techniques, with very few studies offering adequate instrumental comparisons. In the fall of 2007, NH3 concentrations/emissions were monitored for a one week period at a waste treatment lagoon on a 6000-cow dairy in Idaho using five separate methodologies. Up to twenty-five Ogawa passive samplers were dispersed around the perimeter of the lagoon, with a concentrated bank of samplers arrayed along the predicted downwind side of the facility. A URG acid/base gas denuder system, assembles with three series denuders configured for NH3 collection, was collocated at a single sampling site with one of the passive samplers. The collected samples from the passive samplers and the denuder tubes were quantified via ion chromatography at Utah State University. Two separated UV-Sentry open-path ultra violet differential optical absorption spectrometers (UV-DOAS) were used to measure the integrated NH3 concentrations along an approximately 200 m pathlength on both the up and downwind sides of the lagoon. Two infrared Fourier Transform Spectrometers (FTS) were also used to quantify ambient NH3 along the same downwind pathlength. Finally, a small, floating wind tunnel system, coupled with a Thermo Fisher Model 17C chemiluminescence NH3 monitor, was used to measure direct NH3 emissions from the surface of the lagoon. In 2008, NH3 measurements were made at a 950-milking cow dairy in central California. Two FTS systems were employed upwind and downwind of the whole facility, while numerous passive samplers were place throughout the dairy. Quantification of all ambient concentrations have been completed and the measurements will be used in conjunction with inverse modeling techniques (both LaGrangian and Eularian) to estimate lagoon and dairy-wide NH3 emissions

Comparing Three Different Methods for Assessing Corn Silage Density

Silage density is negatively correlated with dry matter losses in storage and has been used as an Extension evaluation tool to assess ensiling management practices on farms. We compared three methods for estimating silage density on 18 farms. Core sampling is the standard method, while the calculator and feed-out methods are new alternative methods. Core sampling results were highly correlated with the calculator method but not with the feed-out method. Core sampling and the calculator method are recommended tools for estimating storage dry matter losses and evaluating alternative ensiling management practices by Extension faculty, producers, and other users

Phosphorus Removal by Silage Corn in Southern Idaho

Corn silage is the predominant crop in Idaho used for recovering phosphorus (P) that has accumulated in soils from dairy manure applications. However, little is known about how much P and other nutrients are being recov- ered under Idaho conditions. The objective of the study is to estimate P removal by irrigated corn silage crops cultivated throughout southern Idaho with variable soil test P concentrations, and to identify effects of increasing soil test P on tissue concentrations of P and on plant P uptake. Forty-two different corn silage fields in 2008 and 2009 were selected throughout southern Idaho for soil and whole plant sampling at harvest. Soils were ana- lyzed for Olsen P, plant tissue was measured for total P content, and dry and wet yields were calculated based on field weights and drying of plant tissue

Using extension phosphorus uptake research to improve Idaho's nutrient management planning program.

Irrigated silage corn is the main crop used for phosphorus removal; however little is known about the actual amounts of phosphorus removed under southern Idaho growing conditions. The purpose of this study was to survey phosphorus removal by irrigated corn grown for silage in southern Idaho under variable soil test phosphorus concentrations. In this survey whole plant corn tissue phosphorus concentrations ranged from 0.116 to 0.307% total phosphorus and averaged 0.208%, which is lower than Natural Resources Conservation Services estimates used prior to 2007 (0.26% phosphorus) but higher than estimates used since 2007 (0.185%). The study was used by NRCS to update nutrient management planning software used by planners in Idaho