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61.
Leaching of phosphorus out of fen soils - Results from pot trials without growing plants In contrast to acid bog peat soils, fen soils with high content of iron, calcium und partially lime may fix phosphates in the same way as mineral soils. In model experiments without growing plants the quantity of leached phosphorus is determined. 0,4–0,5 kg P/ha are leached out of a slightly acid fen soil (pH 5,5) with 550 mm percolated water. The phosphate fertilizers (300 kg P/ha) Tripelphosphat, Novaphos, Hyperphos and Thomasphosphat have no influence on the amount of leached phosphorus. The phosphate is fixed in the depth of 0–10 cm, into which the fertilizers were mixed. However, from a very strongly acid fen soil (pH 3,0; limed in 0–10 cm to pH 4,5) with 1000 mm percolated water 25,8 kg P/ha are leached. The fertilization with Tripelphosphat and Novaphos increases the amount of leached phosphorus whereas the water insoluble phosphate fertilizers (Thomasphosphat and Hyperphos) have no influence. In a fen soil with high content of iron water soluble phosphate will be sorbed and fixed very rapidly, therefore only low parts of the water soluble phosphate fertilizers can be extracted with lactate solution (DL), in comparison to the water insoluble phosphates. 相似文献
62.
Mymarothecium boegeri sp. n. (Monogenea: Dactylogyridae) is described from the gills of Colossoma macropomum Cuvier (Characidae), collected from the aquaria of the "Centro de Pesquisas em Aquicultura, Departamento Nacional de Obras Contra as Secas (DNOCS)", Pentecoste City, State of Ceará, Brazil. Mymarothecium viatorum Boeger, Piasecki et Sobecka, 2002 is reported from the type host, Piaractus brachypomus (Cuvier) (Characidae) and from a new host, P. mesopotamicus (Holmberg) (Characidae), confirming the occurrence of M. viatorum in the Neotropical Region. The new species differs from the congeneric species in the structure of male copulatory complex; it is more closely related to M. viatorum by the presence of a posteromedial projection on ventral bar. 相似文献
63.
Three air contaminants that may have serious health consequences to humans and poultry are ammonia, dust, and aerosolized bacteria. This study measured ammonia concentrations, dust concentrations, and the presence or absence of aerosolized Salmonella spp. and Escherichia coli inside and outside five commercial layer facilities. The average outside ammonia concentration measurements decreased as the distance from the facility increased from 10 to 40 ft. The measurements at 10 ft from the facilities were consistently higher than the average concentrations inside the facilities. The ammonia measurement trends inside of the facilities were affected by the temperature-dependent ventilation systems. Average dust concentrations inside the five facilities were consistently below 2 mg/m3. Three facilities also experienced average outside dust concentrations at all measured distances below 2 mg/m3. Two facilities had relatively high average dust measurements at 10 ft from ventilation fans (32.12 mg/m3 and 75.18 mg/m3). Escherichia coli and Salmonella were isolated from the air inside all five facilities and outside the facilities up to 40 ft from the ventilation fans. In condusion, dust concentrations may pose the largest risk to human and animal health at 10 ft away from the poultry facilities; risks associated with ammonia inhalation are greatest inside facilities during the coolest months of the year; and aerosolized bacteria are found inside and outside poultry facilities, but further work is needed to quantify the bacteria to further assess the health risk related to this issue. 相似文献
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Faires MC 《The Canadian veterinary journal. La revue veterinaire canadienne》2004,45(4):329-331
Over a 44-day period, 4 of 5 affected calves in a 170-head herd of beef cattle died after exhibiting clinical signs of lethargy, ataxia, anorexia, and diarrhea. Histopathological examination of tissues and toxicological analysis of a suspicious powder discovered in the pasture confirmed arsenic trioxide toxicosis. 相似文献
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Jacobsen S Niewold TA Halling-Thomsen M Nanni S Olsen E Lindegaard C Andersen PH 《Veterinary immunology and immunopathology》2006,110(3-4):325-330
The aim of the study was to determine the intraarticular serum amyloid A (SAA) response pattern in horses with inflammatory arthritis. Inflammatory arthritis was induced by injection of lipopolysaccharide (LPS) into the radiocarpal joint of four horses. Serum and synovial fluid (SF) samples were collected before and at 4, 8, 12, 24, 48, 72, 96, and 144 h after injection. Concentrations of SAA were measured by immunoturbidometry, and expression of SAA isoforms was visualized by denaturing isoelectric focusing and Western blotting. The LPS injection caused systemic and local clinical signs of inflammation. Serum amyloid A appeared in serum and SF within 8 h after LPS injection. Isoelectric focusing showed three major SAA bands with apparent isoelectric points (pI) of 7.9, 8.6, and >9.3 in serum and SF. Synovial fluid contained two additional isoforms with highly alkaline apparent pI values (apparent pI value extrapolated from standard curve = 10.0 and 10.2), which were not present in any of the serum samples. In conclusion, intraarticular injection of LPS induced systemic and local inflammatory responses in the horses. By demonstrating SF-specific SAA isoforms the results of the present study suggest that SAA is synthesized locally in the equine inflamed joint, similar to what has been demonstrated in humans previously. The marked local SAA synthesis suggests an important pathophysiological role in inflammatory arthritis. 相似文献
69.
Aloisio F Filippini G Antenucci P Lepri E Pezzotti G Cacciò SM Pozio E 《Veterinary parasitology》2006,142(1-2):154-158
An outbreak of giardiasis was observed in a sheep farm in Central Italy. Infected lambs (30-90 days of age) showed a malabsorption syndrome, decreased weight gain and impairment in feed efficiency. The most relevant clinical sign was the excretion of malodorous and poorly formed faeces, whereas diarrhoea was rarely observed in the flock. Laboratory investigations revealed the presence of Giardia in affected animals, while no other significant viral, bacterial or parasitic pathogens were identified in faeces or tissue samples. A mild to severe infiltrative enteritis with eosinophils, lymphocytes and plasma cells was detected in histological sections of the gut. Giardia parasites collected from duodenal aspirates were typed as Giardia duodenalis Assemblage B, by PCR amplification and sequencing of the TPI gene. Treatment with fenbendazole at a dose of 10mg/kg for 3 consecutive days, successfully cleared the infection. These results show that G. duodenalis can cause significant economic losses in sheep farming. 相似文献
70.
Forterre S Raila J Forterre F Brunnberg L Schweigert FJ 《Veterinary journal (London, England : 1997)》2006,171(3):451-455
The aim of this study was to investigate differences in concentrations of vitamin A, transthyretin (TTR) and retinol-binding protein (RBP) between plasma and cerebrospinal fluid (CSF) in dogs. RBP was detected using ELISA, and both RBP and TTR by Western blot analysis after separation on SDS-PAGE. Vitamin A was determined by high performance liquid chromatography. RBP and TTR as well as vitamin A were detected in all samples but at substantially lower concentrations in CSF compared to plasma. RBP in dog plasma showed a similar molecular mass to that of humans, whereas canine TTR had a lower molecular mass. Comparison between plasma and CSF showed that both RBP and TTR were of lower molecular mass in CSF. In CSF, RBP and retinol were present at 10-100-fold lower concentrations compared to plasma. Retinyl esters were present only in minute amounts in 5/17 samples. In conclusion, the CSF of dogs compared to humans is significantly different in terms of both quality and quantity of transport proteins for vitamin A. 相似文献