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Two dogs with clinical histories suggestive of leptospirosis were examined serologically and culturally for evidence of leptospiral infection. Antibodies to Leptospira interrogans serovar bratislava were detected in serum from one dog, and the organism was isolated from urine of that dog. In a serologic survey of dogs in the state of Illinois, reactor rates to bratislava were higher than those to canicola or icterohaemorrhagiae. In cases of suspect canine leptospirosis, serovars such as bratislava, not contained in canine vaccines, should be considered in a differential diagnosis.  相似文献   
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The aim of this study was to evaluate the influence that different protocols of urethral catheterization after pharmacological induction (Ur.Ca.P.I.) may have on the semen quality of the domestic cat. The study has been divided into two experiments: one in which different dosages of medetomidine administrated are evaluated and the second one in which the timing of the catheterization after pharmacological induction is tested. In the first experiment, 18 cats were sedated with the recommended dosage of medetomidine (130 μg/kg i.m.) while the other 18 were sedated with a lower dose of the same drug (50 μg/kg i.m.). In the second experiment, three groups were implemented, each containing 25 subjects. In group 1, the semen collection was performed immediately once the pharmacological effect of the drug was reached; in group 2, the semen collection was performed three times every 5 min after the pharmacological effect was reached; finally, in group 3, Ur.Ca.P.I. was performed 20 min after the pharmacological effect was reached. All the different protocols permitted sperm collection, nevertheless the first experiment showed a better quality in terms of volume, concentration, total number of spermatozoa (p < 0.01) and quality of the movement (motility p < 0.05 and forward progressive motility p < 0.01), using a high medetomidine dosage rather than 50 μg/kg i.m. In the second experiment, forward motility was statistically higher (p < 0.01) in the first group and total volume was higher (p < 0.01) in the second and third group, while other parameters were statistically not different. Results suggest that a single catheterization immediately after the onset of the pharmacological effect leads to a good‐quality semen with the lowest possibility of damaging the urethra and that a sedation with 130 μg/kg of medetomidine leads to a better quality sperm collection than 50 μg/kg does.  相似文献   
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Two experiments were conducted to evaluate performance and forage utilization characteristics of beef cattle fed ammoniated wheat straw (AWS) unsupplemented except for minerals or supplemented with energy and protein. In Exp. 1, 194 crossbred beef cows (BW = 472 kg) in late gestation were allotted by weight, breed type, and age during two consecutive winters to 12 drylot pens (three pens/treatment) for a 60-d feeding trial. The AWS (3% NH3 wt/wt) was tubground through a 7.6-cm screen, and cows were allowed ad libitum access to the AWS. In Exp. 2, 16 ruminally fistulated Angus x Hereford steers (BW = 300 kg) were blocked by weight and randomized to treatments in a 35-d intake-digestion trial. Daily supplementation treatments in both experiments were Control, no supplemental energy or protein; LSG, 1.36 kg of sorghum grain (SG); HSG, 2.72 kg of SG; and SG + SBM, 1.02 kg of SG + .34 kg of soybean meal (SBM). All animals received .23 kg of mineral mixture formulated to meet a pregnant cow's mineral requirements. Supplements LSG and SG + SBM were fed to provide the same daily ME, and HSG and SG + SBM were fed to provide the same daily CP. Cows were managed as one group during and after calving. In Exp. 1, all supplements increased gain (P less than .01) vs Control, and cows fed SG + SBM had higher (P = .05) gains than those fed LSG. The SG + SBM supplement increased (P less than .01) change in cow body condition score compared with LSG.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   
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In the solar system, the planets' compositions vary with orbital distance, with rocky planets in close orbits and lower-density gas giants in wider orbits. The detection of close-in giant planets around other stars was the first clue that this pattern is not universal and that planets' orbits can change substantially after their formation. Here, we report another violation of the orbit-composition pattern: two planets orbiting the same star with orbital distances differing by only 10% and densities differing by a factor of 8. One planet is likely a rocky "super-Earth," whereas the other is more akin to Neptune. These planets are 20 times more closely spaced and have a larger density contrast than any adjacent pair of planets in the solar system.  相似文献   
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The effect of available C and N on the rate of wheat (Triticum aestivum L.) straw decomposition by microorganisms was determined using electrolytic respirometers under laboratory conditions. Three lots of spring wheat straw containing 1.13, 0.79 and 0.18% N were used. Cold-water soluble C and N were leached from the wheat straw and the respiration from the leached and non-leached straws (1.5 g of each), with and without added N, were compared in a sand system for 881 h. The fraction of soluble C declined as straw N content declined (total soluble C was 14.0, 11.4 and 8.9%, respectively, for the three straws). The fraction of soluble N declined as straw N content declined, but the proportion of total N that was soluble varied with initial straw N content. We postulated from decomposition data for the various treatments that the amount of microbial biomass produced and the overall rate of wheat straw decomposition in the early stages is largely dependent on the size of the soluble C pool and an intermediately-available C pool that is not cold-water soluble but decomposes within the first few days of decay. Our results from this study imply that the amount of N immobilized during wheat straw decomposition is dependent on the amount of available C from both the primary and secondary pools present in the straw. The data also suggest that the soluble C pool and the intermediately-available C pool were metabolized simultaneously.  相似文献   
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Field studies were conducted for three seasons (1978–1979, 1979–1980 and 1981–1982) on a Palouse silt loam near Pullman, Washington, to compare the effects of broadcast and deep banding of nitrogen (N) fertilizer beneath winter wheat (Triticum aestivum L.) seed on N uptake and dry matter production of downy brome (Bromus tectorum L.) and jointed goatgrass (Aegilops cylindrica Host.), and on N uptake, dry matter production and grain yields of winter wheat. Three tillage systems were used: conventional tillage; shallow roto-tilling, or no-tillage prior to planting. Rates of N were 0, 65, 130 and 190 kg N ha−1 as ammonium nitrate. Additional plots were maintained free of weeds at the 130 kg N ha−1 rate. In 1983–1984, deep banding of the fertilizer between rows in a paired-row configuration was compared to surface-broadcast N fertilizer using N rates of 0, 45, 90 and 135 kg N ha−1. There were no significant differences between broadcast and deep-band application of N on grass weed N uptake or dry matter production with mold-board plowed or no-tillage, but there was greater weed growth with surface-broadcast N with shallow roto-tilling. Wheat N uptake, growth and grain yields were consistently higher with band-applied N compared to broadcast N. The yield response to banding N was the same with or without the presence of grass weeds.  相似文献   
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