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HighlightsRye grain compaction was measured for three different moisture contents (8%, 12%, and 16% wet basis) at five different compaction pressures (7, 14, 34, and 55 kPa)Bulk densities were found to be statistically significantly dependent (p < 0.0001) on both the moisture content and applied pressure.Compacted bulk densities increased with increasing applied pressure for all moisture contents.Abstract. Bulk density of agricultural grains is needed to determine the quantity of grain in storage structures and to calculate grain pressures. The objective of this study was to investigate the effects of moisture content and applied pressure on bulk density of rye grain at moisture contents and pressures typical of those seen in storage structures. Rye compaction was measured for three moisture contents (8%, 12%, and 16% wet basis) at four compaction pressures (7, 14, 34, and 55 kPa) using a square box (based on the design used by Thompson and Ross, 1983). Data from the compaction tests were used to calculate the bulk densities for the three moisture contents and four compaction pressures. The bulk densities were found to be significantly dependent (p

Florida’s K–12 schools provide a potential opportunity to increase market channel options for small- and mid-sized diversified farms, but processing, storage, and distribution resources are extremely limited for smaller producers. This 9-page document serves as a model and case study with steps for producers and other stakeholders to conduct a feasibility study before forming a cooperative to sell local fruits and vegetables to schools and other institutional food-service outlets. Written by Jonathan Adam Watson, Danielle D. Treadwell, Catherine Campbell, and Ray Bucklin, and published by the UF/IFAS Department of Agricultural and Biological Engineering, March 2021.

Plants grown in greenhouse-type structures are potential sources of food, oxygen, clean water, fiber, and other resources needed for bioregenerative life support systems during long-term space missions. Identification of cladding materials with appropriate optical and physical properties that can withstand the high ultraviolet radiation, low pressure, and low temperature Martian environment is necessary for greenhouse design. The objective of this study was to evaluate the effects of simulated Mars environmental conditions on yield strength and light transmissivity of composites composed of a layer of 0.15 mm polyimide film (LaRC™CP1) attached to acrylic, polyvinyl chloride (PVC), or polycarbonate cladding materials. The University of Florida’s Mars Simulation Chamber (MSC) at Kennedy Space Center was utilized to expose material samples to simulated Mars environmental conditions. Changes in control versus exposed material sample transmissivities were measured using a spectroradiometer over the PAR range of wavelengths from 400 to 700 nm and material peak yield strengths were determined using an Instron universal testing machine. Keywords: LaRC™CP1, Mars greenhouse, PAR transmission, Plastics, Strength of materials, UV damage.The overall results comparing pre- and post-exposure of samples to simulated Martian conditions in the MSC showed that the addition of a layer of polyimide did not benefit either the transmissivity or strength of polycarbonate cladding materials, but did show benefits in retaining transmissivity for PVC and in maintaining strength for acrylics exposed to Mars simulated environment. However, transmissivities of the plastics were reduced by the addition of protective layers of polyimide. Keywords: LaRC™CP1, Mars greenhouse, PAR transmission, Plastics, Strength of materials, UV damage.

Grain physical properties such as coefficients of friction are required to design harvesting, cleaning, and handing equipment, and storage structures. The objective of this study was to measure coefficients of friction between triticale grain and galvanized steel at grain pressures and velocities typical of those seen when filling and emptying storage bins and hoppers. Coefficients of friction were measured using an apparatus consisting of a box with openings so that a galvanized steel blade could be pulled through a sample of grain. The forces required to pulling the blades through the grain were measured for three different moisture contents [8%, 12%, and 16% wet basis(wb)] and three different normal pressures (6.9, 10.3, and 13.8 kPa). The velocity of the blade being pulled through grain was kept constant at 50 mm/min for all pressures and moisture contents. Keywords: Grain bin, Grain pressure, Grain storage.Coefficients of friction were found to be statistically significantly dependent (p

Air transport has unique characteristics that are essential for the transport of perishable products. However, temperature variations during air transport operations may be detrimental to temperature-sensitive products such as fresh horticultural crops, seafood, pharmaceuticals, and others. The literature on the subject remains scarce. In-flight temperatures were monitored during six international shipments using an aircraft container loaded with simulated perishable products. Results highlighted the overriding impact of solar radiation on temperature distribution within aircraft containers during ramp transfers. Extended ramp transfer durations were observed, and for three shipments the total time, outside, on the tarmac exceeded 11 h, resulting in an average product temperature increase of as much as 13°C. In-flight conditions had a smaller impact on the temperature distribution within the load of products. Tests indicated that the core region of the load was exposed to the smallest rate of heat transfer, and the top layer was exposed to the largest rate of heat transfer. Cold room storage of a fully loaded aircraft container proved to be a very inefficient cooling method. Keywords: Aircraft container, Horticultural products, In-flight, Perishables, Ramp, Tarmac.

Triticale is a hybrid of wheat and rye grown for use as animal feed. In Florida, due to its soft coat, triticale is highly vulnerable to Sitophilus oryzae L. (rice weevil) and there is interest in development of methods to detect early-instar larvae so that infestations can be targeted before they become economically damaging. The objective of this study was to develop prediction models of the infestation degree for triticale seed infested with rice weevils of different growth stages. Spectral signatures were tested as a method to detect rice weevils in triticale seed. Groups of seeds at 11 different levels (degrees) of infestation, 0–62%, were obtained by combining different ratios of infested and uninfested seeds. A spectrophotometer was used to measure reflectance between 400 and 2500 nm wavelength for seeds that had been infested at different levels with six different growth stages from egg to adult. The reflectance data were analyzed by several generalized linear regression and classification methods. Different degrees of infestation were particularly well correlated with reflectances in the 400–409 nm range and other wavelengths up to 967 nm, although later growth stages could be detected more accurately than early infestation. Stepwise variable selection produced the lowest mean square differences and yielded a high R 2 value (0.988) for the 4th instars, pupae and adults inside the seed. Models were developed to predict the level of infestation in triticale by rice weevils of different growth stages. Overall, this study showed a great potential of using reflectance spectral signatures for detection of the level of infestation of triticale seed by rice weevils of different growth stages.

The hot and humid weather in Florida affects dairy cattle performance throughout the year, and producers who hope to achieve optimum production from their dairy cows must provide them with relief from heat and humidity. This 4-page fact sheet written by I. M. Toledo, G. E. Dahl, R. A. Bucklin, and D. K. Beeke and published by the UF/IFAS Department of Agricultural and Biological Engineering describes several cooling strategies to alleviate heat stress in dairy cattle. http://edis.ifas.ufl.edu/ae022

Protecting biological systems and organic materials from high ultraviolet (UV) radiation is a significant issue for engineering materials in both terrestrial and space applications. In this study, the synthesized composites of polystyrene butyl acrylate (PSBA) encapsulated lignin based nanohybrid were evaluated as UV resistant cladding materials for both applications. The UV transmittance of the composite films and their physical, thermal, and chemical degradation after prolonged exposure to high UV radiation (10 Earth days and 30 Mars equivalent days) at low temperatures of 3.4 °C were examined. The results showed that the composite films blocked the UV radiation and there was no significant effect of UV radiation on film integrity, mechanical and thermal properties of the composite films when they were exposed to high intensity UV radiation (132 W/m2) within 24 h. Further, FTIR spectra of the composite films before and after UV radiation demonstrated that the films did not have notable oxidation degradation, although the glass transition temperature was slightly decreased with increased exposure time. Keywords: UV resistance, Lignin nanohybrid, Polystyrene-butyl acrylate, Physical properties, Degradation

Farm to school (F2S) programs aim to educate people about food and farming, to increase the availability of fresh, nutritious foods, and to improve health outcomes among children. Nationally, all states have school districts that self-identify as farm-to-school program participants. National and regional food procurement systems account for the majority of food purchased by National School Lunch Program participants, but school foodservice authorities (SFA) who purchase food from farmers often do so in the context of strengthening their farm-to-school program (U.S. Department of Agriculture [USDA], n.d.-b). A greater number of local supply chain participants benefit when food is sourced in state (locally) rather than out-of-state because more money ends up in the pockets of local producers and distribu­tors. Local fruit and vegetable producers and SFAs interested in developing business partnerships for local procurement would benefit from recommen­dations on menu-appropriate fresh market prod­ucts, volume, and purchase prices. However, detailed data sets from SFAs are uncommon, limiting opportunities to advance procurement efforts. The objective for this project was to begin developing local procurement recommendations for other Florida school districts based on the purchasing history and experiences of the Sarasota County School District (SCSD). In 2014, Sarasota County, Florida, received a USDA F2S implementation grant, affording it the opportunity to develop its local procurement efforts. One deliverable from that project was a robust data set of school food purchases over a two-year period. With permission SCSD, we analyzed seasonal purchase variations and market prices of local and out-of-state fresh fruits, vege­tables, and egg purchases for 38 public schools in the SCSD. In this paper, we present an approach to estimate the potential of local procurement viability in the context of an emerging districtwide F2S program and recommend system changes based on the success of procurement efforts in SCSD and surrounding school districts in Southwest Florida.

Sand is a common bedding material used as a resting surface for dairy freestalls because it does not support bacterial growth, and it provides a high degree of comfort to cows. Existing techniques of assessing the comfort of freestall resting surface materials in the field are subjective, so the objective of this study was to evaluate the use of a Clegg Impact Tester as a method to assess the comfort of sand and various other freestall resting surface materials. The Clegg tester was developed to characterize the stiffness of soils and soil-like materials. The Clegg tester displays a Clegg Impact Value (CIV) based on peak deceleration of the hammer’s impact with a surface from a height of 30 cm, which can be related to the design elastic modulus of a given material. A Clegg Impact Soil Tester with a 1-kg hammer was used in this study. Values were recorded for a rubber mat, a soft foam mat, a hard foam mat, and a waterbed and then were compared with values from sand with varying moisture content. The softest resting surface material was the soft foam (1.07 CIV/L) followed by dry sand (moisture content

The application of bioluminescent sensors for monitoring key metabolites and enzymes that are indicators of stress in plants is demonstrated. The sensitivity of bioluminescent assay for NAD(P)H and NAD(P)(+) was about 0.5 and 1 nmol, respectively. The levels of NAD(P)H and NAD(P)(+) in radish (Raphanus sativus) root extracts from controls and from stress-induced conditions were compared. To induce environmental stress, the plants were grown in enclosed environmental chambers with low pressure (9 or 32 kPa), high humidity (>80%) and low oxygen partial pressure (down to 3.3-6.5 kPa). The concentrations of NAD(P)(+) and NAD(P)H in plants varied under stress conditions. Decreasing both total pressure from 101.5 to 32 or 9 kPa and partial pressure of oxygen increased the ratio of NAD(P)(+) /NAD(P)H from 0.2 to 4 or 6, respectively. The increase in this ratio suggests that plants are undergoing stress in these hypobaric environments. The developed bioluminescent assay for quantification of pyridine nucleotides in plant tissues is rapid, low-cost and easily performed.

Plants grown on long-term space missions will likely be grown in low pressure environments (i.e., hypobaria). However, in hypobaria the transpiration rates of plants can increase and may result in wilting if the water is not readily replaced. It is possible to reduce transpiration by increasing the partial pressure of CO 2 (pCO 2 ), but the effects of pCO 2 at high levels (>120 Pa) on the growth and transpiration of plants in hypobaria are not known. Therefore, the effects of pCO 2 on the growth and transpiration of radish ( Raphanus sativus var. Cherry Bomb II) in hypobaria were studied. The fresh weight (FW), leaf area, dry weight (DW), CO 2 assimilation rates (C A ), dark respiration rates (DR), and transpiration rates from 26 day-old radish plants that were grown for an additional seven days at different total pressures (33, 66 or 101 kPa) and pCO 2 (40 Pa, 100 Pa and 180 Pa) were measured. In general, the dry weight of plants increased with CO 2 enrichment and with lower total pressure. In limiting pCO 2 (40 Pa) conditions, the transpiration for plants grown at 33 kPa was approximately twice that of controls (101 kPa total pressure with 40 Pa pCO 2 ). Increasing the pCO 2 from 40 Pa to 180 Pa reduced the transpiration rates for plants grown in hypobaria and in standard atmospheric pressures. However, for plants grown in hypobaria and high pCO 2 (180 Pa) leaf damage was evident. Radish growth can be enhanced and transpiration reduced in hypobaria by enriching the gas phase with CO 2 although at high levels leaf damage may occur.

Environmental conditions in an air-conditioned barn and in evaporatively cooled sprinkler and fan and tunnel-ventilated barns are compared and recommendations for dairy barn design for hot, humid climates are given. Temperature Humidity Indexes (THI) observed in the air-conditioned barn were always below 72. Average THIs in the evaporatively cooled barns during afternoon hours were seldom less than 75.

Myer, R.O., Brendemuhl, J.H. and Bucklin, R.A. 2008. Effect of season on growth performance of finishing pigs fed low-protein, amino acid supplemented diets. J. Appl. Anim. Res., 34: 1–8. A two year study was conducted to evaluate the effects of diet (low-protein diets supplemented with crystalline amino acids (aa) vs. high-protein, non aa supplemented control diets) and season/rearing environment (hot, humid summer vs. cool fall/winter) on growth performance and carcass lean content of finishing pigs (52 to 110 kg). For each year, two trials, each with 84 pigs, were conducted. Outside daily high and low temperatures (C) and RH (%), respectively, averaged 26, 21 and 81; 26, 20 and 83; 14, 7 and 80; and 10, 3 and77for yr 1 and 2 summer and y r 1 and 2 fall I winter, respectively. Diets were maize and soybean meal based (3.3 meal ME/kg). The low-protein (LP) diets were four percentage units lower in crude protein (CP) than the corresponding control diets; crystalline lysine, threonine, tryptophan a...

Plants will likely be significant components of life support systems for future manned exploration missions to Mars. Design constraints make it necessary to maintain a greenhouse on Mars at pressures in the range of 0.1 to 0.25 of Earth standard pressure (101.3 kPa). The resistance to sensible and latent heat loss decreases with pressure, which may cause increased rates of plant evapotranspiration, leading to possible water stress of plants growing in hypobaric conditions. The objective of this research was to analyze the effect of pressure and air velocity on convective heat transfer from a flat plate in hypobaric conditions to simulate leaf convective heat transfer in a greenhouse on Mars. Convective heat transfer analysis was performed both theoretically and experimentally for a flat plate. A classical heat transfer model for both free and forced convection regimes was compared with data from controlled experiments. As predicted, external resistance was proportional to both pressure and air velocity. The thickness of the velocity boundary layer increased significantly at low pressures and air velocities less than 1 m s-1.

A system of three small-scale hypobaric plant chambers was designed and built to simulate a Mars greenhouse environment and evaluate effects of this environment on evapotranspiration of radish plants. A glass bell jar was sealed atop aluminum bases designed to house a heater, fans, humidifier, and wiring. A data acquisition and control program was developed to control pressure, air temperature, relative humidity, and carbon dioxide concentration as well as monitor leaf temperature and plant weight. The system was successful as demonstrated by the average standard deviations from the set points during performance tests (set points in parentheses): pressure, 0.2 kPa (12 kPa); CO2 concentration, 235 ppm (9000 ppm); air temperature, 0.17°C (24°C); and relative humidity, 1.03 % (70 %).

Proper nutrient management is essential to increase yield, quality and profit. This study was conducted to estimate the N concentrations of chinese cabbage (Brassica campestris L. ssp. pekinensis `Norangbom') plug seedlings using visible and near infrared spectroscopy for nondestructive N detection. Chinese cabbage seeds were sown and raised in three 200-cell plug trays filled with growing mixture in a plant growth chamber with three different levels (40%, 80%, and 100%) of required N. Reflectance for leaves of chinese cabbage seedlings was measured with a spectrophotometer 15 days after the experiment started. Reflectance was measured in the 400 to 2500 nm wavelength range at 1.1-nm increments. The leaves were dried afterwards to measure their water content and were analyzed for their actual N contents. The experiment was repeated twice (group I and II). Correlation coefficient spectrum, standard deviation spectrum, stepwise multiple linear regression (SMLR), and partial least squares (PLS) regression were used to determine wavelengths for N prediction models. Performances of SMLR and PLS were similar. For the validation data set (group II), SMLR produced an r2 of 0.846 and PLS yielded r2 of 0.840. The most significant wavelength 710 nm, which was identified by all methods, was correlated to chlorophyll. Water content positively correlated with N concentration (r = 0.76). Wavelengths of 1467, 1910, and 1938 nm selected by SMLR from both groups also showed that water had a strong effect on N prediction. Wavelengths near 2136 nm indicated that protein had potential use in N prediction. Wavelengths near 550 and 840 nm could also contribute to N prediction.

An eight-week study evaluated the effects of flow rate and dietary protein on the function of sand and gravel biological filters for ornamental fish production. Forty tiger barbs, Barbus tetrazona, were placed in each of twelve, 38-L tanks. Upflow sand and gravel filters operated at non-fluidization flow rates of 57.5 L/hour and 111 L/ hour were compared. Diets with 32%, 40%, and 42% protein contents were compared. Total Ammonia Nitrogen (TAN) levels were significantly lower in the tanks with 57.5 L/hour filters. TAN levels were also significantly (P 0.05) by either flow rate or dietary protein level. Fish growth rate was not affected (P >0.05) by water flow rate, but gro...

Claw lameness may be associated with biomechanical factors caused by imbalances of the pressure distribution under hooves when cows are confined on hard concrete flooring. Using a system based on a thin pressure measurement film (Matscan, Tekscan, Inc., South Boston, Mass.) developed for pressure distribution analysis of human feet, the pressures under the hooves of a population sample of 32 cows divided into trimmed and untrimmed groups were measured under dynamic conditions (stance phase) and compared to evaluate the effects of trimming in correcting the imbalance caused by overgrowth of hoof tissues. The results, obtained for three different points of the stance phase, showed that the pressure distribution under the medial sole, heel bulb, and toe of trimmed cows changed slightly as compared to untrimmed cows. The medial sole displayed higher peak pressures as compared to the heel bulb and toe, which displayed lower peak pressures at the midstance phase. In the acceleration phase, the overall peak pressures shifted to the toe, except on the rear feet of untrimmed cows, which maintained slightly greater (2.5%) peak pressures at the heel bulb than at the toe. The deceleration phase showed similar peak pressures at the heel bulb and lateral sole for both trimmed and untrimmed cows. It was concluded that trimming results in slightly higher pressures towards the medial sole. This may help improve gait stability by removing some of the peak pressures at the heel bulb and lateral sole (weight-bearing border). However, the higher peak pressures at the medial sole may cause an increase in stresses on that region and favor the incidence of lesions, particularly sole ulcers.

Measurement of wall loads in hoppers has been difficult due to the expense of constructing multiple loads cell measurement units in a hopper. Recent advances in measurement techniques have allowed significant improvements in the measurement of multiple point normal stresses in hoppers. This paper presents measurements of wall stresses using pressure sensitive pads made by TekScan™. The wall stresses in a Diamondback Hopper™ were measured, indicating significant spatial stress variation. These hopper stresses were used to compute spatially varying K-values using a modified Janssen stress approach. The Janssen stress ratio approach with varying K-values that were a function of local hopper slope angle generated wall load curves that captured the general behavior of the observed wall loads.

Experimental and mathematical models were developed for describing and testing temperature and humidity parameters for plant production in bioregenerative life support systems. A factor was included for analyzing systems operating at low (10-101.3 kPa) pressure to reduce gas leakage and structural mass (e.g., inflatable greenhouses for space application). The expected close relationship between temperature and relative humidity was observed, along with the importance of heat exchanger coil temperature and air circulation rate. The presence of plants in closed habitats results in increased water flux through the system. Changes in pressure affect gas diffusion rates and surface boundary layers, and change convective transfer capabilities and water evaporation rates. A consistent observation from studies with plants at reduced pressures is increased evapotranspiration rates, even at constant vapor pressure deficits. This suggests that plant water status is a critical factor for managing low-pressure production systems. The approach suggested should help space mission planners design artificial environments in closed habitats.

The steady flow of soybeans over a smooth aluminum surface and over a bumpy glass bead surface was studied. High speed video was used to aid in analysis of frictional and collisional flow and the transition between these regimes. The greatest discharge rate was observed during high velocity frictional flow. The highest velocity frictional flow occurred in the chute at slopes near the angle of friction between the surface and soybeans. The highest velocity frictional flow was observed at approximately 18° for the smooth (aluminum) surface and 20° for the bumpy (glass bead) surface. Damage to the soybeans increased with increasing velocity over a given surface. Also, more damage occurred in the collisional flow regime. The average mass percentage of damage was 2.2% for control soybeans that had not flowed through the chute. The average mass percentage of damage was 3.4% for the frictional flow regime and 4.2% for the collisional flow regime. The average germination rate for control soybeans that had not flowed through the chute was 91.5%. The germination rate was 87.0% for the frictional flow regime and 81.5% for the collisional flow regime.

Wall loads were measured in a model bin 2.44 m in diameter and 7.3 m tall equipped with a bottom unloading wall flume. The results were then compared to the wall loads measured during unloading of this same bin without the flume. During most of unloading the wall loads measured when using the flume were smaller than those during filling. However, at the onset of discharge a load spike was observed prior to the formation of the funnel-flow discharge pattern. Wall moments in the direction of the flume were observed to occur which were three times as large as those measured during centric unloading.

A milking parlor simulation and a stochastic model for a capital budget for the parlor were used to determine economically preferred parlors within three milking facility sizes [40 stalls (double-20 herringbone or double-20 parallel), 64 stalls (two double-16 herringbones, two double-16 parallels, or a double-32 parallel), and 80 stalls (two double-20 herringbones, two double-20 parallels, or a double-40 parallel)] and economically preferred operating characteristics (pulsation ratio and vacuum pressure) and management strategies (milking procedures and amounts of milking labor). Net returns indicated that the preferred parlor for 40 stalls was the double-20 parallel. The preferred parlors for 64 stalls were two double-16 parallels and for 80 stalls were two double-20 parallels. The economic advantage for these parlors versus alternative parlors ranged from $688,940 (double-20 parallel) to $2,793,855 (two double-20 parallels). Analyses indicated that values of all preferred parlors were maximized by operation at a high vacuum pressure (50.8 kPa), a wide pulsation ratio (70:30), minimal milking procedures (attach units and postdip), and minimal amounts of milking labor (20 to 32 units per milker). Parallel parlors had higher values than did herringbone parlors, and multiple, small (two double-16 or two double-20) parallel and herringbone parlors had higher values than did single, large (double-32 or double-40) parallel parlors.

Biological filters designed to remove toxic ammonia excreted as fish wastes are an integral part of any recirculating aquacultural system. The quantity of ammonia excreted by fish is related to the quantity of nitrogen supplied by the protein contained in feed. This experiment evaluated short term Total Ammonia Nitrogen (TAN) production by juvenile tilapia fed rations with six different protein contents. Five feeds composed using soybean meal as their protein source and one feed deriving most of its protein content from fish meal were tested. Statistically significant increases (P < 0·10) in TAN production were observed as protein content increased during the 24 h period following feeding. Fish meal and soybean meal did not produce statistically different TAN production rates.

The coefficient of restitution of soybeans impacting aluminum, glass, and acrylic was measured for drop heights of 15.1 cm, 29.2 cm, and 51.1 cm and at moisture contents of 10.7% and 15.5% (db). Statistically significant changes in the coefficient of restitution were produced by changes in material surface, drop height and moisture content. Changes in moisture content from 10.7% to 15.5% (db) reduced the average coefficient of restitution from 0.69 to 0.59, a decrease of approximately 14%. Over the range of impact velocities tested (1.7 to 3.2 m/s produced by drops from heights from 15.1 cm to 51.1 cm) the coefficient of restitution was relatively insensitive to velocity, decreasing by less than 5% from 0.65 to 0.62. The measured values of coefficient of restitution were used as inputs to algorithms describing the behavior of a single bouncing soybean. The algorithm predicted reasonable results when compared to the observed behavior of dropped soybeans.

Physiological parameters, such as body temperature, are key indicators of heat stress and disease indairy cows. Heat stress is a major complication in dairy production and is known to predisposecows to significant health problems such as mastitis, poor reproductive performance, andlameness. It is therefore important to develop improved means of monitoring deep bodytemperature. The purpose of this project is to show a comparison between two methods ofmeasuring deep body temperature of dairy cows. Cow body temperatures measured by ingestedand implanted CorTemp sensors and rectal thermometers were compared in an effort to developan accurate and relatively non-invasive means of monitoring body temperature. The CorTemp sensor, patented by HTI Technologies, Inc., is a wireless transmitter in the shapeof a pill. It consists of a quartz crystal temperature sensor, a telemetry system, and a battery. Thesize of the pill varies based on the application. The smallest pills intended for human use orpoultry are 27 mm long and 10 mm in diameter. The size differs based primarily on the size of thebattery; the larger the battery the longer the life of the sensor. The transmitter pill can be ingestedby the cow or implanted. The sensor provides a continuous and accurate means of monitoringtemperature of dairy cows when implanted or as it travels through the digestive tract. Two tests ofthe sensor were conducted at the Dairy Research Unit (DRU) at the University of Florida. Thefirst trial was conducted on a rumen fistulated Holstein cow. A CorTemp sensor was manuallyplaced into the lower rumen of the cow through its cannula. Temperatures recorded by theexternal receiver were compared to rectal temperatures measured using a mercury thermometer. Asecond trial was conducted using three Holstein cows at the DRU. A sensor was surgicallyimplanted into the abdomen between the greater omentum and right abdominal wall. Again,temperatures were recorded by the receiver, as well as rectally by a mercury thermometer.The trials were conducted to compare temperatures measured by the CorTemp sensor totemperatures measured by a rectal thermometer. Both the rectal thermometer and CorTempsensor gave deep body temperatures within the normal range for dairy cows (38.3-39.4oC).Analysis of the temperatures indicated that the temperatures measured by the CorTemp sensorwere statistically the same at the 98% level for Cow 1, 97% level for Cow 2 and 95% level forCow 3. Further studies are planned to develop the CorTemp system as a tool to measure cowdeep body temperature.

Insect infestation of triticale (Triticosecale) seed causes extraordinary storage losses as a consequence of vulnerability of triticale seed to insect infestation and its soft coat. Rice weevil, Sitophilus Oryzae (L.), is a common insect that causes infestation in Florida, which was the focus of this research. The objective of this research was to develop a method to determine the degrees of infestation (DI) in the seed at two growth stages by measuring their spectral reflectance. To achieve this goal, triticale samples with eleven DI (0, 6, 11… and 62%) were prepared with two growth stages of larvae 2nd instar, and adult outside seed with three to four replications. The reflectance was measured from 400 nm to 2500 nm. The DI results were compared to manual inspection in order to evaluate the accuracy. The data was analyzed using stepwise multiple linear regression (SMLR). The result showed that the DI for larvae 2nd instar stage could be detected using an average reflectance in 400 - 410 nm, with an R 2 of 0.87 using the SMLR method. The adult outside stage also resulted in a good prediction using the SMLR method, where it yielded four wavelengths (400, 783, 791, and 967 nm) that provided an acceptable result with an R 2 of 0.87 for the adult outside stage. The prediction of early growth stages was more challenging than for late growth stages, due to the smaller size of larvae 2 nd instar stage compared to the adult stage. Overall, NIR spectroscopy was proved to be useful to detect insect infestation in triticale seed.

Agricultural grains, including cereal grains such as wheat, corn and rice, and oil seeds such as soybeans and canola, must be stored, transported, and conveyed using methods that preserve their quality as seeds, food stuffs, or raw materials. Grain quality is maintained by drying grain to moisture contents suitable for long-term storage on farm or in commercial facilities. Grain storage facilities must be designed to withstand loads imposed by the grain along with other environmental loads. Methods to calculate loads on storage structures and applicable design codes are outlined. Methods of handling and transporting grain and modeling techniques to model loads and flow behavior are explained.

Triticale is being studied as a substitute for corn in animal feed and as a forage crop for Florida. Storage of triticale seed is difficult in Florida’s climate, and more information about equilibrium moisture content (EMC) relationships of triticale is needed to develop improved storage methods. Therefore, the research objective was to measure the EMC for triticale seed and to determine the best fit equation representing the EMC. This study measured the EMC of triticale at three different temperatures 5, 23, and 35°C using a static method using six desiccation jars with six different salt concentrations. These salts provided relative humidities (RH’s), of 11, 23, 33, 58, 75, and 84% at 25°C. An average of ten weeks was required to reach equilibrium when the initial moisture content (MC) of the seed was 13% (wet basis). The results of this experiment were used to develop a prediction algorithm representing the relationship between RH and EMC with coefficient of determination (R 2 ) equal to 0.99. It was also found that the Modified Henderson equation represents this relationship accurately. Overall, this result will aid the development and improvement of drying and storage methods for triticale seed.

Test blades of galvanized steel were pulled through wheat to study the frictional behavior between wheat and the blades. The effects of wear and dust accumulation on wheat grains were studied by pulling three blades through grain samples which had been conveyed in repeated cycles in mass flow and bucket conveyors. The test blades were pulled at a velocity of 0.05 mm/min and at overbearing grain pressures of 3.9, 6.6, 9.2, and 11.8 kPa. No statistically significant influences (a = 5%) of grain wear or overbearing pressure were found on the coefficient of friction between wheat and galvanized steel. Slip-stick behavior was observed in all of the tests of the effects of wear on wheat grains.

Feces and urine were collected separately from individual cows fed corn silage-based (50% of dry matter) diets which were supplemented with distillers dried grains plus solubles or soybean meal to be 14 or 18% crude protein (CP). Fecal samples from 30 cows were screened using wet sieving and vibrating screens (nested in series); sizes were 3.35, 2.00, 1.40, 1.00, and 0.50 mm. Effluent passing the screens contained 60.2% of total solids (TS), 86.3% of nitrogen (N), and 94.3% of phosphorus (P). Solids caught on the five screens (largest to smallest) accounted for the following percentages of materials: 14.6, 9.4, 2.8, 4.3, 8.6% of TS; 5.7, 3.1, 0.8, 1.3, 2.8% of N; 2.2, 1.2, 0.3, 0.6, 1.5% of P. In another study, a 100 g composite sample of urine and feces from each of 44 cows, mixed in proportion to the amount excreted, was diluted to 1 L with water and allowed to settle for 1 h in a graduated cylinder. Supernatant and sediment were separated by decanting. Supernatants were analyzed for N content, sediments for TS content, and these amounts were subtracted from analyzed contents of samples to obtain reciprocal fractions. Overall, the sediment contained 66% of TS and 45% of N. Estimates of sediment amount made at 5, 10, 20, 40, and 60 min by recording best-defined line between supernatant and sediment suggested sedimentation was 89% completed by 5 min. In a second sedimentation study, simulated manure flushwaters (0.5, 1.0, and 1.5% TS) were treated with additives as follows: (1) 0.75 g of CaC03 plus 0.50 mL Fe2(SO4)3 solution/L, (2) 0.75 g of Ca0 plus 0.50 mL Fe2(SO4)3 solution/L, (3) 0.50 mL Fe2(SO4)3 solution/L plus five drops of a commercial polymer, and (4) control (no additives). Precipitates with CaCO3 and CaO treatments contained 92% of the TS, 69% of the N, and 31% of the total potassium (K); the CaO treatment precipitated appreciably more P (93% of total) than other treatments; and treatment with Fe2(SO4)3 plus polymer precipitated the least TS and N. These data indicated a potential to remove more manure solids and N from flushed manure by sedimentation than by screening.

Twenty-four cows were housed in an open-sided feed barn. The water runoff from a fan and sprinkler system was collected and measured. Water evaporation was estimated by comparing the quantity of water applied by the sprinkler system to the quantity of water collected as runoff from the barn. The study consisted of two 14-day periods. During period 1 the cows were housed in the barn, and during period 2 the barn was empty. Statistically significant differences were found in the quantity of water collected in the two periods (P > 0.0001). An estimated total of 4.0 L (1.1 gal) per cow per hour evaporated in the barn. An estimated 2.7 L (0.7 gal) of water per cow per hour evaporated from the cows’ hair coats. An estimated total of 23% of the water emitted by nozzles evaporated and an estimated 15% of the total water emitted from the nozzles evaporated from the cows’ hair coats. To evaporate 4.0 L (1.1 gal) of water during 1 h requires 2708 W (9240 BTU/h), while evaporating 2.7 L (0.7 gal) of water during 1 h requires 1828 W (6237 BTU/h). These values are much greater than the tabulated value of the sensible heat output of 300 W (1024 BTU/h) for a 500 kg (1100 lb) dairy cow during a 1-h period. This indicates that the potential exists to further reduce the quantity of water applied by the fan and sprinkler cooling system.

Tests were conducted to study sources of variation in the dynamic coefficient of friction of corn on galvanized steel. The factors analyzed were grain moisture content, grain pressure, and number of trials. The coefficient of friction was statistically significantly lower for 12% (w.b.) moisture content corn than for 16% (w.b.) moisture content corn. The coefficient of friction decreased with repeated sliding contact between metal and grain for all pressures and moisture contents. No significant influence of pressure on the dynamic coefficient of friction was seen.

[First paragraphs]: All living organisms respond to their environment through sensible and latent heat exchange processes. Many problems in animal agriculture involve interactions with environmental factors--temperature, humidity, solar radiation, and wind--which govern these processes. The interplay among temperature, humidity, and solar radiation can be critical, as there is a defined range of thermal conditions within which animals can maintain homeothermy through behavioral and physiological means, while continuing to consume feed at levels needed to maintain production and health (Hahn, 1999). Management decisions for livestock or environmental control systems require accurate environmental measurements. Livestock research also requires accurate monitoring and control of environment to develop needed relationships between such measures for developing models of animal performance.

Cow comfort was evaluated in a freestall barn at the University of Florida Dairy Research Unit during the summer of 2008 by comparing the effects of three bedding materials on freestall usage, hock health, and leg hygiene. The bedding materials were sand, waterbeds, and the waterbeds with approximately 1.5” (3.81cm) of sand on top. Video surveillance was used to examine the interaction between the cows and freestalls for the 2 four week trials. Trial one consisted of a sand bedded herd and a waterbed herd. Trial two consisted of a sand bedded herd and waterbeds with sand on top herd. Each herd was housed in a different section of the barn. The interaction between the freestalls and the cows was quantified into cow orientation: lying, standing, or perching within stalls, and empty stalls. A total of 112 freestalls were used for the experiment, 56 for each treatment. The sand bedded freestalls resulted in the highest overall lying percentage (52.95%) and the waterbeds resulted in the highest percentage of empty stalls (49.02%). Injuries to the hocks were highest for both the waterbeds and the waterbeds with sand on top (1.24). The waterbeds alone had the dirtiest cows with a highest least square mean hygiene score of 2.62.

Hot, humid weather causes heat stress in dairy cows leading to declines in feed intake, milk production, and fertility. These declines can be reduced or eliminated by using a heat stress relief program consisting of a combination of shades, feed and water offered under shade, ventilation, and sprinkler and fan cooling. Results from experimental studies in Florida and Kentucky indicate that sprinkling and fan cooling systems in combination with shades can improve cow comfort and increase milk production of cows in hot, humid climates.

Flow patterns were observed as com and wheat were discharged from four clear plastic flat bottom model bins. Grain was discharged from storage conditions in which the initial grain depths and outlet locations were varied. The type of flow was observed to vary with grain depth and outlet location. For H/S (height to cross-section distance or diameter) ratios less than 1.25, wheat and com always discharged in funnel flow. Wheat discharged in intermediate flow for 1.25