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51.
This paper discusses compost production yields as a percent of raw product mix using poultry litter, poultry processing plant dissolved air flotation skimmings, sawdust, wood chips and ground yard debris. Three different mixes were used and identified as Mixes 1, 2 and 3. Mixes 1 and 2 were produced using windrows and a windrow turner and Mix 3 was made using a covered in-channel compost turner. Mixes 1 and 2 were poultry litter compost with a screened mass yield of 80 and 77 percent, respectively. Mix 3 was a dissolved air flotation compost with a screened mass yield of 40 percent. Results from plant experiments show poultry litter compost can be used successfully in potting mixes for poinsettia and chrysanthemum production. A compost produced from dissolved air flotation skimmings, a poultry processing waste, can be used in field corn production but had little influence in the production of soybeans. 相似文献
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Alternate technologies of compost manufactured from poultry litter (manure) were studied as a means of producing a value-added product for the landscape and nursery industry. Static pile and turned windrow technologies were investigated on a commercial scale with the composting of nearly 300 tons of material. The major difference between the technologies is the amount of energy and labor required. Static pile systems require less energy but more time than windrow turned systems. There was no process advantage found for passively aerated static piles over static piles but costs of passive aeration for pipes and labor were higher than for static piles. Machine turned windrows completed active temperature production within 100 days while portions of both the static and passively aerated piles continued to actively compost past 300 days. Process operational costs and compost quality were similar among the compost methods studied. Production operational cost is driven by the cost of compost ingredients and accounted for 60 to 70% of the cost in the pilot study. Ingredients were poultry litter, wood chips and sawdust. Screened compost was produced at an operational cost of $30 while unscreened compost could be produced for $20 per ton of compost. A production scheme where poultry litter is static pile composted on farms for later transport to regional processing centers appears feasible. This two-part composting procedure will eliminate the transport of raw litter and improve poultry biosecurity. Most likely, a private compost business would provide the expertise, on-farm compost procedures and operate the regional facility. 相似文献
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Tamzen K. Stringham Keirith A. Snyder Devon K. Snyder Samuel S. Lossing Craig A. Carr Bennett J. Stringham 《Strength and Conditioning Journal》2018,71(3):327-335
The expansion of piñon and juniper trees into sagebrush steppe and the infilling of historic woodlands has caused a reduction in the cover and density of the understory vegetation. Water is the limiting factor in these systems; therefore, quantifying redistribution of water resources by tree species is critical to understanding the dynamics of these formerly sagebrush-dominated rangelands. Tree canopy interception may have a significant role in reducing the amount of rainfall that reaches the ground beneath the tree, thereby reducing the amount of available soil moisture. We measured canopy interception of rainfall by singleleaf piñon (Pinus monophylla Torr. & Frém.) and Utah juniper (Juniperus osteosperma [Torr.] Little) across a gradient of storm sizes. Simulated rainfall was used to quantify interception and effective precipitation during 130 rainfall events ranging in size from 2.2 to 25.9 mm hr? 1 on 19 trees of each species. Effective precipitation was defined as the sum of throughfall and stemflow beneath tree canopies. Canopy interception averaged 44.6% (± 27.0%) with no significant difference between the two species. Tree allometrics including height, diameter at breast height, stump diameter, canopy area, live crown height, and width were measured and used as predictor variables. The best fit predictive model of effective precipitation under canopy was described by stump diameter and gross precipitation (R2 = 0.744, P < 0.0001). An alternative management model based on canopy area and gross precipitation predicted effective precipitation with similar accuracy (R2 = 0.741, P < 0.0001). Canopy area can be derived from various remote sensing techniques, allowing these results to be extrapolated to larger spatial scales to quantify the effect of increasing tree canopy cover on rainfall interception loss and potential implications for the water budget. 相似文献
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Stickle JE McKnight CA Williams KJ Carr EA 《Veterinary clinical pathology / American Society for Veterinary Clinical Pathology》2006,35(2):250-253
A 2-year-old, Quarter Horse filly was referred to Michigan State University, Veterinary Teaching Hospital with a 2-3 day history of depression and partial anorexia progressing to severe, watery diarrhea with severe neurologic abnormalities, including repetitive muscle fasciculations, muscle stiffening, and collapse. Laboratory findings included severe polycythemia, neutropenia, metabolic acidosis, and electrolyte and fluid loss, consistent with watery diarrhea and endotoxic shock. Increased creatine kinase and aspartate transaminase activities were consistent with recent transport and the muscle abnormalities. Severe hyperammonemia (1369.0 micromol/L; control value, 15.3 micromol/L) was found, without other substantial laboratory evidence of hepatic dysfunction. The horse was euthanized because of poor prognosis and rapid clinical deterioration. Necropsy findings were unremarkable with the exception of severe diffuse colitis. Culture of colonic contents recovered >1000 colony-forming units of Clostridium perfringens. Based on these findings, marked hyperammonemia in this filly was attributed to changes in colonic flora leading to increased bacterial production of ammonia that was readily absorbed through the inflamed bowel wall, exceeding the hepatic capacity for deamination. Intestinal bacteria as a source of hyperammonemia in the absence of hepatic disease has been linked rarely to positive culture results for clostridial organisms. 相似文献
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Dhumeaux MP Snead EC Epp TY Taylor SM Carr AP Dickinson RM Leis ML 《Journal of Feline Medicine and Surgery》2012,14(10):701-705
This study evaluated the effects of an anesthetic protocol using intravenous ketamine and midazolam, and intramuscular buprenorphine on hematologic variables in cats. Twelve healthy adult cats had blood collected for a complete blood count before and after the induction of anesthesia. There were significant decreases in red blood cell counts, hemoglobin concentrations and hematocrits after the induction of anesthesia. On average, red blood cell counts and hematocrits decreased by 25%, and hemoglobin concentrations decreased by 24%. Based on hematocrit, 3/12 samples (25%) taken while the cats were anesthetized would have been interpreted as belonging to anemic patients while none of the cats would have been considered anemic before anesthesia. This study suggests that a complete blood count performed on blood taken under anesthesia with this anesthetic protocol should be interpreted cautiously in order to not make a false diagnosis of anemia. 相似文献