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31.
A condition colloquially referred to as "limber tail" and "cold tail" is familiar to people working with hunting dogs, primarily Pointers and Labrador Retrievers. The typical case consists of an adult dog that suddenly develops a flaccid tail. The tail either hangs down from the tail base or is held out horizontally for several inches from the tail base and then hangs straight down or at some degree below horizontal. Initially, the hair on the dorsal aspect of the proximal tail may be raised and dogs may resent palpation of the area 3-4 inches (8-10 cm) from the tail base. Most dogs recover spontaneously within a few days to weeks. Anecdotal reports suggest that anti-inflammatory drugs administered within 24 hours after onset hasten recovery. Less than one half of affected dogs experience a recurrence. Affected Pointers almost always have a history of prolonged cage transport, a hard workout the previous day, or exposure to cold or wet weather Most owners and trainers familiar with the condition do not seek veterinary assistance. In cases where people are not familiar with this disease, other conditions such as a fracture, spinal cord disease, impacted anal glands, or prostatic disease have been incorrectly diagnosed. We examined 4 affected Pointers and found evidence of coccygeal muscle damage, which included mild elevation of creatine kinase early after onset of clinical signs, needle electromyographic examination showing abnormal spontaneous discharges restricted to the coccygeal muscles several days after onset, and histopathologic evidence of muscle fiber damage. Specific muscle groups, namely the laterally positioned intertransversarius ventralis caudalis muscles, were affected most severely. Abnormal findings on thermography and scintigraphy further supported the diagnosis.  相似文献   
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Procedures are described for the analysis of crops for residues of tetrachlorvinphos (Gardona, trans-isomer of dimethyl 1-(2′,4′,5′-trichlorophenyl)-2-chloroyinyl phosphate) insecticide together with methods for the analysis for residues of its isomer and its conjugated and non-conjugated breakdown products. Suitable procedures for the extraction are described together with procedures for the cleanup of the extracts by partition or column chromatography and final analysis down to 0·01 ppm or less by gas-liquid chromatography with electron capture detection.  相似文献   
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A procedure has been developed for the analysis of crops and soils for residues of trifenmorph (N-trityl-morpholine) molluscicide and its breakdown product triphenylcarbinol (TPC). Samples were extracted with 20% by vol. acetone in petroleum ether and the efficiency of the extraction was established using radiochemical techniques. The extracts were subjected to column chromatography on basic alumina columns to separate trifenmorph from the TPC. The residues were converted to trichloroethyl ether derivatives followed by clean-up by column chromatography on silica gel and analysis of down to 0·02 ng by gas-liquid chromatography. Blank values were generally 0·01–0·02 ppm, recoveries were on average about 80% and were limited to this value by the yield of the etherification reaction. The storage stability of the residues at —10°c was satisfactory.  相似文献   
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The consequences of the use of swirl assessment at a bovine artificial breeding centre were studied. Data relating to the amount of semen discarded, fertility of accepted semen, the relationship between discard rates and age of bull and ejaculate number have been presented. The overall differences in fertility between semen with swirl ratings, 5, 6 and 7 were very small. About 50% of all ejaculates collected in the period considered were discarded at the first inspection. The discard rate tended to be greater in young and in older bulls. The discard rate was significantly greater (P less than or greater to 0.001) for second ejaculates. It was considered that a proportion of rejected semen may have been of good fertility. Semen wastage after freezing was low.  相似文献   
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