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Nutrient excretion, phosphorus characterization, and phosphorus solubility in excreta from broiler checks fed diets containing graded levels of wheat distillers grains with solubles
Get PDFIncreased interest in ethanol production
in North America has led to increased production of
distillers dried grains with solubles (DDGS), the majority
of which are fed to livestock. To determine the
impact of including wheat DDGS in broiler diets on
nutrient excretion and P characterization and solubility,
125 one-day-old male broiler chicks were fed wheat and
soybean meal-based diets containing 0, 5, 10, 15,
or 20% wheat DDGS. There were 5 replicate pens per
treatment, with 5 birds per pen arranged in a randomized
block design. Apparent retention of both N and
P were determined by using the indicator method.
Nutrients excreted per kilogram of DM intake were
also calculated. Characterization of excreta P was determined
by 31P-solution nuclear magnetic resonance
spectroscopy, and water-soluble P (WSP) was determined
by extraction of excreta with deionized water.
The apparent retention of both N (P < 0.001) and P
(P < 0.008) decreased linearly with increasing inclusion
rates of DDGS from 0 to 20%. The nutrient output per
kilogram of DM intake increased linearly with increased
DDGS inclusion rate for N (P < 0.04), P (P < 0.0001),
and WSP (P < 0.0003). As the inclusion rate of DDGS
increased, the P concentration in excreta increased (P
< 0.008), whereas excreta phytate P concentrations decreased
(P < 0.01), which led to an increase in WSP
and the fraction of total P that was soluble. Because
the inclusion of DDGS in poultry diets increased N and
P output, as well as the solubility of P excreted, care
should be taken when including high levels of DDGS in
poultry diets, because increases in N and P excretion
are a concern from an environmental standpoint
Predicting soil-extractable Zn, P, Fe, and Cu in a biosolids-amended dryland wheat agroecosystem
Get PDFBiosolids Beneficial Use Programs frequently involve multiple applications at agronomic rates, with plant-nutrient availability changing as elements react with soil constituents over time. Consequently, can regression equations reasonably estimate plant availability of Zn, P, Fe, and Cu, where multiple applications of Littleton and Englewood, Colorado Wastewater Treatment Plant biosolids are applied to a dryland wheat (Triticum aestivum L.)-fallow agroecosystem? Before each growing season, we added Littleton and Englewood biosolids at rates of 0 to 11.2 dry Mg ha−1 to plots arranged in randomized complete blocks with four replications per treatment. Soil samples collected after each wheat harvest were analyzed using an NH4HCO3-diethylenetriaminepentaacetic acid extraction. We completed planar (included the number of applications and elemental additions), linear, quadratic, and exponential-rise-to-a-maximum (as a function of elemental additions only) regression analyses for six applications at two sites. We found that the planar regression models provided superior R2 values and SE of the estimate in almost all cases. These results suggest that lability changes as biosolids-borne Zn, P, Fe, and Cu react with the soil over time. Consequently, predictions of nutrient availability involving multiple biosolids applications to dryland wheat-fallow agroecosystems should account for the number of biosolids additions
Interaction of calcium and phytate in broiler diets: 1. Effects on apparent prececal digestibility and retention of phosphorus
Get PDFPhytate P utilization from soybean meal (SBM) included in broiler diets has been shown to be poor and highly dependent on dietary Ca intake. However, the effect of Ca on P utilization and on the optimal ratio of Ca to nonphytate P (Ca:NPP) when diets contained varying levels of phytate has not been clearly shown and was the objective of this research. A factorial treatment structure was used with 4 dietary Ca levels from 0.47 to 1.16% and 3 levels of phytate P (0.28, 0.24, and 0.10%). Varying dietary phytate P levels were obtained by utilizing SBM produced from 3 varieties of soybeans with different phytate P concentrations. Ross 508 broiler chicks were fed 1 of 12 diets from 16 to 21 d of age. Excreta were collected from 16 to 17 d and from 19 to 20 d of age and ileal digesta was collected at 21 d of age. Apparent prececal P digestibility decreased when dietary Ca concentration increased and was higher when diets contained low-phytate SBM. The apparent digestibility of Ca and percentage of phytate P hydrolysis at the distal ileum were not reduced when dietary phytate P concentration increased. Including low-phytate SBM in diets reduced total P output in the excreta by 49% compared with conventional SBM. The optimum ratio of Ca:NPP that resulted in the highest P retention and lowest P excretion was 2.53:1, 2.40:1, and 2.34:1 for diets with 0.28, 0.24, and 0.10% phytate P. These data suggested that increased dietary Ca reduced the extent of phytate P hydrolysis and P digestibility and that the optimum Ca:NPP ratio at which P retention was maximized was reduced when diets contained less phytate P
Varietal differences in rate of carbohydrate accumulation for tall fescue
Get PDFTotal non-structural carbohydrates (TNC) accumulate during daylight because photosynthesis produces more TNC
than are metabolized for plant growth and maintenance. The net balance of leaf photosynthesis, respiration, and carbohydrate
export produces a diurnal variation in TNC such that minimum concentrations occur in early morning and maximum in late
afternoon. The objectives were to determine variability of TNC concentrations among cultivars, and to investigate daily rates of
carbohydrate accumulation in tall fescue (Lolium arundinaceum (Schreb .) S J . Darbyshire= Festuca arundinacea Schreb .
Comparison of nitrogen fertilization methods and rates for subsurface drip irrigated corn in the semi-arid Great Plains
Get PDFIn semi‐arid areas such as western Nebraska, interest in subsurface drip irrigation (SDI) for corn is increasing
due to restricted irrigation allocations. However, crop response quantification to nitrogen (N) applications with SDI and the
environmental benefits of multiple in‐season (IS) SDI N applications instead of a single early‐season (ES) surface application
are lacking. The study was conducted in 2004, 2005, and 2006 at the University of Nebraska‐Lincoln West Central Research
and Extension Center in North Platte, Nebraska, comparing two N application methods (IS and ES) and three N rates (128,
186, and 278 kg N ha-1) using a randomized complete block design with four replications. No grain yield or biomass response
was observed in 2004. In 2005 and 2006, corn grain yield and biomass production increased with increasing N rates, and
the IS treatment increased grain yield, total N uptake, and gross return after N application costs (GRN) compared to the ES
treatment. Chlorophyll meter readings taken at the R3 corn growth stage in 2006 showed that less N was supplied to the plant
with ES compared to the IS treatment. At the end of the study, soil NO3-N masses in the 0.9 to 1.8 m depth were greater under
the IS treatment compared to the ES treatment. Results suggested that greater losses of NO3-N below the root zone under the
ES treatment may have had a negative effect on corn production. Under SDI systems, fertigating a recommended N rate at
various corn growth stages can increase yields, GRN, and reduce NO3-N leaching in soils compared to concentrated
early‐season applications
Copper sulfate foot baths on dairies and crop toxicities – What are the risks?
Get PDFA rising concern with the application
of dairy wastes to agricultural
fields is the accumulation of
copper (Cu) in the soil. Copper
sulfate (CuSO4) from cattle foot
baths are washed out of dairy
barns and into wastewater lagoons.
The addition of CuSO4
baths has been reported to increase
Cu concentration significantly
in manure slurry from 4.8
g/1000 L to 88.6 g/1000 L (Miner
Institute, New York). The Cu enriched
dairy waste is then applied
to agricultural crops, thus
raising concerns about how soils and
plants are impacted by these Cu additions
Acrylamide monomer leaching from polyacrylamide-treated irrigation furrows
Get PDFWater-soluble anionic polyacrylamide (WSPAM), which
is used to reduce erosion in furrow irrigated fields and other
agriculture applications, contains less than 0.05% acrylamide
monomer (AMD). Acrylamide monomer, a potent neurotoxicant
and suspected carcinogen, is readily dissolved and transported in
flowing water. The study quantified AMD leaching losses from
a WSPAM-treated corn (Zea mays L.) field using continuous
extraction-walled percolation samplers buried at 1.2 m depth.
The samplers were placed 30 and 150 m from the inflow source
along a 180-m-long corn field. The field was furrow irrigated
using WSPAM at the rate of 10 mg L−1 during furrow advance.
Percolation water and furrow inflows were monitored for AMD
during and after three furrow irrigations. The samples were
analyzed for AMD using a gas chromatograph equipped with an
electron-capture detector. Furrow inflows contained an average
AMD concentration of 5.5 μg L−1. The AMD in percolation
water samples never exceeded the minimum detection limit and
the de facto potable water standard of 0.5 μg L−1. The risk that
ground water beneath these WSPAM-treated furrow irrigated
soils will be contaminated with AMD appears minimal
Bacteria and yeast associated with sugar beet root rot at harvest in the Intermountain West
Get PDFAn undescribed wet rot of roots was observed in surveys of recently harvested sugar beet roots
in Idaho and eastern Oregon in 2004 and 2005. Microorganisms isolated from 287 roots fell into
the following groups: A (41% of strains), B (29%), C (17%), D (11%), E (2%), and F (1%).
Groups A, B, C, and F were composed of bacteria while groups D and E were yeasts. Subgroup
A1 (80% of group A strains) included Leuconostoc mesenteroides subsp. dextranicum strains
and subgroup A2 (20%) contained Lactobacillus strains. Group B was dominated by subgroup
B1 (92% of strains), which included Gluconobacter strains. When only one organism was isolated
from rotted roots, strains from subgroup A1 were isolated most frequently. Group C was
composed of enteric bacteria. Strain B322 of L. mesenteroides subsp. dextranicum caused the
most severe rot on root slices and produced symptoms similar to those in harvested roots. Results
suggest that L. mesenteroides subsp. dextranicum is among the first bacterial species to
enter sugar beet roots, closely following fungal infections or entering directly through openings
such as growth cracks. The bacterial rot leads to yield loss in the field but likely also leads to
storage and factory-processing problems
Response of BGMV and BGYMV resistant common bean to beet curly top virus
Get PDFCrop losses can be severe when susceptible large-seeded Andean dry and green bean cultivars are planted early in dry areas with a history of curly top caused by Beet curly top virus (BCTV) and closely related species. In order to assess the level of curly top resistance in 65 diverse dry and green bean genotypes, seed was planted in a commercial field in Kimberly, ID in 2007. Viruliferous beet leafhoppers were released approximately 3 weeks after emergence to generate an artificial epiphytotic. Plants were rated on a scale of 1-5 (1 = healthy, 5 = highly susceptible) 5 weeks after infestation and verified at fully developed pod stage (R8). Capri and UI 51 were among the most susceptible genotypes, while A 429, DOR 390, DOR 500, and G 2402 did not exhibit any symptoms. In general, breeding lines and cultivars with known resistance to Bean golden mosaic virus and Bean golden yellow mosaic virus (except Morales) were resistant to moderately resistant to BCTV. Additional testing will be required to verify the resistance followed by research to determine the evolutionary origin of the genes for resistance to these viruses
Phosphorus losses in runoff after application of litter from broilers fed high-available phosphorus corn feed
Get PDFRecent efforts to reduce phosphorus (P) content of corn grain fed to poultry
have led to the development of low-phytic-acid corn. Research is needed to evaluate
the environmental impact of the application to cropland of manure from animals fed
low-phytic-acid corn. The purpose of this research was to determine P losses in
runoff from a bare Piedmont soil (cecil clay loam; clayey, kaolinitic, thermic, Typic
Kanhapludult) in the southeastern United States receiving surface applications of
broiler litter from birds fed a low-phytic-acid corn (HAP broiler litter). The HAP
litter was applied at rates of 0, 8, 16, 33, 49, 66, and 82 kg P ha-1
. Simulated
rainfall was applied at a rate of 7.6 cm hr-1 on the same day the litter sources were
applied to the plots. Runoff volumes were measured, and samples were collected at
5-min intervals for 30 min and analyzed for reactive P (RP), algal-available P
(AAP), and total P (TP). Flow-weighted concentrations and mass losses of P
increased linearly with litter application rate (r2 values ¼ 0.99). Flow-weighted concentrations
of RP in runoff increased from 2.2 to 15.4 mg RP L-1, and mass loss of
TP in runoff ranged from 1.3 to 7.3 kg P ha-1 over all application rates based on
linear regression. Runoff volume losses were 47% greater after litter applications
compare to the 0 application rate treatment. Reduced infiltration resulting from litter
particles blocking pores in the soil surface is likely the reason for the increased runoff
volumes