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131.
Two male English Setters were noticed to be breathing rapidly, hyperexcitable, and atactic after roaming a rural area for 2 hours. Both dogs' cost were stained with yellow liquid. One dog died while en route to the veterinarian. Treatment was begun for the surviving dog for what was initially diagnosed to be organophosphorus or carbamate insecticide toxicosis. Before the diagnosis could be confirmed, the second dog died. The yellow liquid on the dogs' skin was identified as dinoseb in high concentrations. Dinoseb is an acutely toxic, substituted dinitrophenolic herbicide believed to act as an uncoupler of electron transport from oxidative phosphorylation.  相似文献   
132.
Prevalence of Cryptosporidium sp in equids in Louisiana   总被引:3,自引:0,他引:3  
In 1985, 22 pony foals reared in a helminth-free environment were tested daily for oocysts of Cryptosporidium sp by use of fecal flotation. Oocysts were found in all foals. Oocysts were first observed in feces collected from foals 9 to 28 days after birth. The mean period of oocyst shedding was 10 days and ranged from 2 to 18 days in individual foals. Diarrhea was observed in 14 of 22 (64%) foals and began before the period of oocyst shedding. Fecal samples also were examined for other infective agents. Salmonella poona was isolated from 1 foal that did not have diarrhea, and coronavirus particles were observed in the feces of 2 foals with diarrhea. Cryptosporidium sp oocysts also were observed in feces of 2 of 17 Thoroughbred foals, 3 of 14 Quarter Horse foals, and 3 of 26 pony foals reared on pastures with their dams. Samples from pasture-reared foals were collected at irregular intervals. Of the 11 Cryptosporidium-positive fecal samples collected from pastured foals, 2 were from foals with diarrhea. A similar survey was conducted during the 1986 foaling season, using the same procedures. Examination of 300 samples from 58 Quarter Horse, Arabian, and pony foals did not detect oocysts. Daily examination of feces from 10 pony foals reared under helminth-free conditions for 30 days also failed to detect Cryptosporidium oocysts.  相似文献   
133.
Antibodies to bovine serum albumin were detected in swine sera by use of an immunoblotting technique. Such sera had false-positive reactions, as determined by results of African swine fever virus serodiagnostic techniques when bovine serum albumin was a contaminant in the soluble cytoplasmic antigen obtained from infected cells cultured in the presence of bovine serum. The soluble cytoplasmic antigen obtained from cell cultures infected with African swine fever virus in the presence of porcine serum did not react with the false-positive sera and, therefore, was used for African swine fever virus serodiagnostic methods, with 0% false-positive results.  相似文献   
134.
Inclusion of high-ionic strength buffers helped us to develop a sandwich ELISA to detect hemorrhagic septicemia virus (HSV) in cell culture and infected trout tissue extracts. For maximal sensitivity of 0.1 to 0.2 ng/well/100 microliters or about 10 to 50 TCID50/well/100 microliters, trout extracts were diluted 1:1 and assayed for the earliest synthesized nucleoprotein N. Simultaneous binding of the N protein from HSV in the sample to the wells coated with monoclonal antibody (2D5 against the N protein) and to the peroxidase-labeled monoclonal antibody (2C9 against the N protein) proceeded during a 2-hour incubation at 20 to 22 C (room temperature). The response was linear between 6 to 60 ng/well of purified virus. Monoclonal antibodies used were noncompetitive with each other and reacted with F1, F2, 23.75, and 5 Spanish isolates of HSV, but not with infectious hematopoietic necrosis or infectious pancreatic necrosis viruses. Tissue specimens with low content of HSV virus may now be assayed directly without use of cell culture, rapidly, and with high precision, during the acute phase of the disease in salmonid fishes.  相似文献   
135.
Male and female Sprague-Dawley rats were given CGS 21595, a pro-drug that is almost immediately metabolized to CGS 19213, a naphthoquinone that acts as a 5-lipoxygenase inhibitor. The compound was administered by gavage to five groups of Sprague-Dawley rats (group Nos. 1, 5, n = 30; group Nos. 2-4, n = 20) at daily doses of 0, 50, 150, 500, or 1,000 mg/kg for 13 weeks. Rats in the higher dose groups had a reduced weight gain, but significant neurologic signs were not observed. A peripheral neuropathy consisting predominantly of myelin destruction in the spinal nerve roots and sciatic nerves in male rats treated with greater than or equal to 150 mg/kg CGS 21595 and in female rats treated with greater than or equal to 50 mg/kg CGS 21595 for 13 weeks. This lesion was not fully reversible after a recovery period of 4 weeks. Lesions consisted of ballooning of myelin sheaths, infiltration by macrophages, demyelination, and occasional areas of remyelination. Axons were generally preserved, and the brain and spinal cord were not affected. Male and female rats in all treatment groups had cytoplasmic hyaline droplets in the proximal renal tubules. This change was reversible after 4 weeks and was not associated with any other adverse effects on the kidney.  相似文献   
136.
The average passage time, the rumen fluid volume and the digestibility of the organic matter were determined in addition to 3 individual feeding experiments with fertility oriented crossbreed ewes, which received pelleted straw-concentrate mixtures. The average passage time of the feed particles through the digestive tract is shorter in pregnant animals than in lactating ones. It is longest in non-pregnant sheep. High quotas of straw and coarse particles prolong the passage time, increasing feed intake and supplements of long straw shorten it. The volume of rumen fluid is lower in ewes fed ad libitum in the stage of late pregnancy and after lactation than during lactation. The rumen fluid volume is also lower in restrictively fed animals during the stage of late pregnancy than during lactation. In animals in the stage of late pregnancy it correlates negatively with the weight of the litter. On an average of all experiments at maintenance level the digestibility of the organic matter in ewes in the 4th month of pregnancy gravidity amounted to 56.6%, in the 2nd month of lactation to 59.8% and in wethers to 59.5% Due to an increase of energy intake from maintenance to 2. maintenance digestibility of the straw-concentrate mixture with 40% straw decreased by 5.5 units and of that with 60% straw by 17.8 units in the period before delivery. Pregnancy in the 4th month resulted in a digestion depression of between 3.0 and 5.8 units.  相似文献   
137.
To evaluate the transplacental transfer of Theileria sergenti infection in cattle, we used DNA probes to detect T. sergenti in 6 pregnant cows and their calves. All the animals were monitored by parasitologic, serologic, and polymerase chain reaction (PCR) assays for a predicted 875-base-pair (bp) DNA product and a 684-bp amplicon detected by nested PCR in the blood and spleens of aborted fetuses. An open reading frame (ORF) starting at nucleotide 170 and terminating at position 1021 was shown to code for a polypeptide of 283 amino acid residues. All 6 dams and 5 calves were positive for T. sergenti in all tests. One calf was positive only with nested PCR. We conclude that transplacental transmission of T. sergenti is a significant problem. The relevance of the data in the programmed introduction of new (especially pregnant) animals into established clean herds needs serious consideration with regard to control of theileriosis and other tickborne diseases.  相似文献   
138.
Manipulated Mouse Embryos as Bioassay System for Water Quality Control   总被引:1,自引:0,他引:1  
Mouse pronuclear stage embryos with intact slit zona pellucida (manipulated) were cultured in vitro until the hatched blastocyst stage in simplex optimized medium with higher K+ concentration (KSOM) prepared with three different water types: tap, deionized reverse osmosis (D‐O) water and Milli‐Q system (M‐Q) water. The culture media were supplemented with or without protein and ethylenediaminetetraacetic acid (EDTA, disodium salt). The rates of hatched blastocysts were significantly affected (p < 0.01) by micromanipulation, protein supplement and water source. The water source has no influence (p > 0.05) on development in EDTA‐supplemented protein‐free culture media, whereas in EDTA‐ and protein‐free culture media, the water quality significantly (p < 0.001) affected the rates of development, with higher rates in media prepared with M‐Q water. The micromanipulated embryos showed higher sensitivity to the water quality (p < 0.01). It worth mentioning that the rates of hatched blastocysts in protein‐free culture media were very low (0–7.5%). Furthermore, the three different water types were analysed by measuring the electrical conductivity, inorganic ions, total organic carbon and endotoxins to evaluate the purity. M‐Q water showed the lowest levels of inorganic ion, total organic carbon and endotoxin concentrations. We concluded that manipulated mouse embryos are good system to evaluate the quality of water used in biological system.  相似文献   
139.
Dogs (n = 13), which had failed to be cured of giardiosis following chemotherapeutic measures, were treated with a Giardia vaccine (2-3 injections). Clinical signs resolved between 16 and 42 days postvaccination and cessation of fecal cyst shedding was between 21 and 70 days. Vaccination is a potential method of treating giardiosis in dogs.  相似文献   
140.
Abstract. The Pan‐European Soil Erosion Risk Assessment (pesera ) model was evaluated using existing soil erosion data collected under various types of climate, vegetation, landscape and soil conditions. The data used represent a variety of typical Mediterranean land uses such as winter wheat, vines, olives and bare, stony land prevailing in hilly areas. Using this data, the model was calibrated for sediment transport by overland flow and results compared to measured soil erosion values from runoff plots and a watershed on a monthly basis. The performance of the model was assessed statistically, showing that it can be satisfactorily used for predicting soil erosion rates under the conditions included in the study. The overall model estimate including all the available experimental data was 0.69 t ha?1 yr?1 with a maximum error of 1.49 t ha?1 yr?1. After validation, the model was applied to a small watershed (60 ha) of great ecological importance for the sea turtle Caretta caretta. For this purpose, soil and vegetation maps were compiled from all the necessary data for applying the model. The model was run for three years using daily data from an existing nearby meteorological station. The predicted and measured soil erosion rates for a 7‐month period were 0.31 t and 0.18 t, respectively. Application of the model to each mapping unit showed the over‐riding importance of land use for sediment generation under the given climatic conditions. Bare land, occupying 5.5% of the watershed area, generated up to 69% of the total sediments estimated for the watershed. It is concluded that the pesera model can be used as a regional diagnostic tool under a range of soil, topographic and climatic conditions for identifying the best land use type and vegetation cover to protect hilly areas from soil erosion. The calculated overall root mean square error for the model is 0.06 t ha?1 yr?1, compared to a soil erosion rate of 0.04 t ha?1 yr?1, which can be tolerated for protecting the area for the sea turtle.  相似文献   
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