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排序方式: 共有146条查询结果,搜索用时 46 毫秒
1.
A previously undocumented hypokalaemic condition with a cyclical nature, comprising acute bouts of polymyopathy followed by spontaneous recoveries, is described in the cat. Cats being fed a high protein vegetarian diet developed recurrent episodes of polymyopathy, characterised by ventroflexion of the head and neck, stiff forelimb gait, lateral head-resting and generalised muscle weakness. Plasma potassium concentrations (mean +/- standard deviation) were reduced from 3.28 +/- 0.33 mmol/l at the beginning of the experiment to 2.45 +/- 0.24 mmol/l during bouts of myopathy. This hypokalaemia was associated with increased creatine kinase activities indicative of muscle damage, and decreased urinary potassium concentrations, and was caused by insufficient dietary potassium. Cats that received the same diet supplemented with potassium did not develop hypokalaemic polymyopathy. Spontaneous recoveries of affected cats were not associated consistently with increases in plasma potassium concentrations. Plasma taurine concentrations decreased and glutamic acid increased markedly in all cats fed the experimental diet. There was no evidence of thiamin deficiency associated with the high glutamic acid intake. Veterinarians should be aware that hypokalaemic cats, and in particular those on potassium-deficient diets, may show cyclical disease with episodes of polymyopathy recurring after periods of spontaneous clinical recovery. This condition in cats may be a useful animal model for familial hypokalaemic periodic paralysis in humans. 相似文献
2.
Two trials were conducted to determine the effects of breed type, backgrounding program, and backfat end point (USBFEP) as determined by ultrasound on the performance and carcass characteristics of feedlot steers. Trial 1 utilized 144 large-framed Charolais- (304.6 +/- 16.3 kg) and 144 medium-framed Hereford-cross steers (294.8 +/- 20.9 kg). Trial 2 utilized 88 medium-framed Angus (289.5 +/- 15.0 kg), 88 large-framed Charolais- (299.8 +/- 17.7 kg), and 88 medium-framed Hereford-cross (291.1 +/- 20.9 kg) steers. Within breed type, short- (70 d) or long-term (126 d) backgrounding programs (Trial 1) and 6- or 12-mm USBFEP (Trials 1 and 2) were assigned. In both trials, carcass size was greater (P < 0.05) for the large-framed Charolais-cross steers, longer backgrounding, and fatter USBFEP treatments. Lean meat yield was greater (P < 0.05) for Charolais- than Hereford-cross steers (Trial 1) and for the leaner USBFEP (Trials 1 and 2). Marbling was greater (P < 0.05) for Angus- (Trial 2) and Charolais- (Trials 1 and 2) than Hereford-cross steers (Trials 1 and 2) and for the fatter end point (Trials 1 and 2). It was concluded that breed type, backgrounding program, and USBFEP were effective in altering growth and could be used to target carcass traits of interest for value-based marketing programs. 相似文献
3.
Cook RW Jolly RD Palmer DN Tammen I Broom MF McKinnon R 《Australian veterinary journal》2002,80(5):292-297
OBJECTIVE: To characterise neuronal ceroid lipofuscinosis (NCL) in Merino sheep. DESIGN: A prospective clinical, pathological, biochemical and genetic study. PROCEDURE: NCL cases were studied from a medium-wool Merino flock, the stud of origin of its replacement rams, and an experimental flock established at the University of Sydney. RESULTS: Behavioural changes and visual impairment were first detected at 7 to 12 months of age and progressed, with associated motor disturbances and at later stages seizures, to premature death by 27 months of age. At necropsy there was severe cerebrocortical atrophy associated with neuronal loss, astrocytosis and the presence in neurons of eosinophilic intracytoplasmic storage bodies with the characteristics of a lipopigment. In the retina there was progressive loss of photoreceptor cells. Storage bodies isolated from fresh brain, liver and pancreas formed electron-dense aggregates and coarse multilamellar and fine fingerprint profiles ultrastructurally, and consisted mainly of the hydrophobic protein, subunit c of mitochondrial ATP synthase. A homozygosity mapping approach localised the gene causing the disease in Merino sheep to the chromosomal region (OAR7q13-15) associated with NCL in South Hampshire sheep. CONCLUSION: NCL in Merino sheep is a subunit c-storing disease, clinically and pathologically similar to NCL in South Hampshire sheep. We propose that the disease in both breeds represents mutation at the same gene locus in chromosomal region OAR7q13-15. 相似文献
4.
K L Baucus S L Ralston C F Nockels A O McKinnon E L Squires 《Journal of animal science》1990,68(2):345-351
Incidence of early embryonic death (EED) and associated changes in serum cortisol, progesterone and plasma ascorbic acid (AA) in transported mares were investigated. Mares were transported for 472 km (9 h) during either d 16 to 22 (T-3 wk, n = 15) or d 32 to 38 (T-5 wk, n = 15) of gestation. Blood samples were drawn from control, nontransported mares (NT-3 wk, NT-5 wk, n = 24) and transported mares pre-trip, midtrip, and at 0, 12, 24, 48 and 72 h post-transport and daily for the next 2 wk. Incidence of EED between transported and nontransported mares was not different (P greater than .05). Serum cortisol in all transported mares increased (P less than .05) relative to pre-trip values at midtrip and 0 h post-transport. Relative to NT mares, serum cortisol was higher (P less than .05) at midtrip in T-3 wk mares and 0 h post-transport in T-5 wk mares. Serum progesterone in all T mares increased (P less than .05) at midtrip relative to pre-trip values and was higher (P less than .05) in T-3 wk mares than in NT-3 wk mares at midtrip and 0 h post-transport. Post-transport decreases (P less than .05) in concentrations of progesterone were observed in mares that aborted. Plasma AA in transported mares increased (P less than .05) at midtrip in T-5 wk mares and decreased (P less than .05) relative to pre-trip values at 24 and 48 h post-transport (T-3 wk and T-5 wk mares, respectively).(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
5.
Water column production and nutrient characteristics in mangrove creeks receiving shrimp farm effluent 总被引:1,自引:0,他引:1
Water column processes in undisturbed mangrove creeks and in creeks receiving effluent from shrimp farms in North Queensland, Australia, were studied. Small scale discharges into tidal creeks did not elevate dissolved nutrient concentrations compared with non‐impacted creeks, but did elevate concentrations of particulate nutrients, chlorophyll and suspended solids proximal to the site of the effluent discharge. Rates of primary and bacterial production downstream from the discharge exceeded rates in the shrimp ponds because of the synergistic effects of turbulent mixing and eutrophication. In the lower reaches of the mangrove creeks and immediately offshore, standing stocks of particulate material and rates of primary and bacterial production were within the range of values found in non‐discharge areas. Our results suggest that water column production by phytoplankton and bacteria strips nutrients from shrimp farm effluent and repackages them in more bioavailable forms. 相似文献
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8.
Grundy WM Buratti BJ Cheng AF Emery JP Lunsford A McKinnon WB Moore JM Newman SF Olkin CB Reuter DC Schenk PM Spencer JR Stern SA Throop HB Weaver HA;New Horizons Team 《Science (New York, N.Y.)》2007,318(5848):234-237
The New Horizons spacecraft observed Jupiter's icy satellites Europa and Ganymede during its flyby in February and March 2007 at visible and infrared wavelengths. Infrared spectral images map H2O ice absorption and hydrated contaminants, bolstering the case for an exogenous source of Europa's "non-ice" surface material and filling large gaps in compositional maps of Ganymede's Jupiter-facing hemisphere. Visual wavelength images of Europa extend knowledge of its global pattern of arcuate troughs and show that its surface scatters light more isotropically than other icy satellites. 相似文献
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10.
Malm O Guimarães JRD Castro MB Bastos WR Viana JP Branches FJP Silveira EG Pfeiffer WC 《Water, air, and soil pollution》1997,97(1-2):45-51
Informal economy of gold mining has contaminated some important river basins in Amazon. Follow-up studies on critical compartments showed some areas with high Hg levels in fish as well as in human hair samples. Average Hg in piscivorous fish in the Madeira river itself was 846 ppb (N=284) with a maximum of 3921 ppb. Mercury in fish from non polluted areas in this basin shows high variability, even for single species. A seasonal variation in Hg content was observed, with higher values at the end of the dry season. In the upper Tapajós basin comparable values were found for fish but with a definite decreasing trend downstream. Average value for piscivorous fish in the whole Tapajós basin is 482 ppb (N=122) with a maximum value of 3770 ppb. Hair Hg was higher in fishing villages in the Tapajós (average: 17 ppm; with N=432 and maximum value of 176 ppm) than in the Madeira (average: 9 ppm; N=169; maximum 71 ppm), and data from some areas of the Tapajós suggest a decrease with time. Mercury was much higher in urine of goldshop workers in Santarém (low Tapajós) than in Alta Floresta (high Tapajbs) and show a decreasing trend in both cases, probably related to the significant decline in gold mining activities during the study period (1986–1994). 相似文献