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11.
PJ BLACKALL Ø ANGEN N FEGAN LL BLACKALL R MUTTERS M BISGAARD 《Australian veterinary journal》2001,79(9):634-639
OBJECTIVE: To characterise eight isolates of a Gram-negative organism obtained from the upper respiratory tract of cattle showing evidence of mild upper respiratory tract disease. DESIGN: The isolates were compared with the five recognised species within the genus Mannheimia - M haemolytica, M glucosida, M granulomatis, M ruminalis and M varigena--using a range of phenotypic and genotypic methods. RESULTS: Phenotypic characterisation indicated that the isolates belonged to the trehalose-negative [Pasteurella] haemolytica complex. This complex has recently been reorganised into five species within the new genus Mannheimia. Ribotyping performed using HindIII and a computerised analysis system indicated that the eight Australian isolates formed a distinct cluster that was related to, but different from, the five recognised species of Mannheimia. The 16S rRNA sequence of one isolate (BNO311) was determined and a phylogenetic analysis performed. Isolate BNO311 was distinct from the five named Mannheimia spp but did join a larger cluster consisting of rRNA cluster IV (M varigena) and the unnamed rRNA cluster V of Mannheimia. DNA:DNA hybridisation between isolate BNO311 and M haemolytica NCTC 9380T, M granulomatis P411 and Actinobacillus ligniersii NCTC 4189T all suggested similarities of approximately 30%. CONCLUSIONS: These phenotypic and genotypic characterisation studies suggest that the eight Australian isolates represent a new species of Mannheimia. Until further characterisation studies are performed, we are unwilling to propose a name for this taxon, preferring to refer to this possible new species as Bisgaard taxon 39 of cluster V of Mannheimia. 相似文献
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IF Canisso LL Coffee K Ortved SL Fubini LV Monteagudo DH Schlafer RO Gilbert 《Reproduction in domestic animals》2014,49(6):e64-e69
An 8‐year‐old, mixed breed, polled goat was presented for evaluation of male‐like behaviour. Clinical findings included clitoromegaly, a heavily muscled neck, pronounced beard, and erect dorsal guard hairs, which are phenotypic characteristics commonly observed in intersex animals. Transrectal ultrasonography revealed the presence of two abdominal masses caudolateral to the uterine horns. Serum concentration of estradiol was elevated. Genetic evaluation was compatible with polled intersex syndrome defined by an XX karyotype without a Y chromosome or SRY gene. Based on gross and histologic evaluation, the abdominal masses were determined to be intra‐abdominal testes, each of which was effaced by Sertoli cell and interstitial (Leydig) cell tumours. The Sertoli cell tumours (SCTs) represented two unique histologic patterns. Regardless of pattern, neoplastic Sertoli cells were consistently lipid laden and positive for vimentin. Interstitial cell tumours (ICTs) were negative for vimentin. Clinical and histopathologic findings suggest that prolonged exposure to steroids secreted by neoplastic Sertoli cells contributed to virilization. In addition, results from immunohistochemistry indicated that vimentin may be a valuable immunodiagnostic tool for differentiation between interstitial and Sertoli cell tumours in goats. 相似文献
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Characterization of mesenchymal stem cells in bovine endometrium during follicular phase of oestrous cycle 
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下载免费PDF全文 E Lara N Rivera D Rojas LL Rodríguez‐Alvarez FO Castro 《Reproduction in domestic animals》2017,52(5):707-714
Stem cells have been postulated as responsible for cell regeneration in highly and continuously regenerative tissues such as the endometrium. Few studies in cattle have identified and specified the presence of stem cells in the endometrium during the oestrous cycle. The aim of this study was to investigate the presence of mesenchymal stem cells (MSCs) in the bovine endometrium during the follicular phase (FP) of the oestrous cycle. Uterine tissue was collected in the time‐frame comprising day 18 of the cycle and ovulation (day 0). We isolated, cultured and expanded four primary cell lines from endometrium and identified byRT‐qPCR the expression of OCT4, SOX2 but not NANOG (undifferentiated/embryonic markers), CD44 (MSCs marker) and c‐KIT (stem cell marker) genes; and the encoded Oct4, Sox2 and Cd44 proteins by Western blot or immunostaining of paraffin‐embedded tissue in endometrium. We demonstrated that cells isolated from bovine endometrium displayed essentially the same gene expression pattern; however, at the protein level, Oct4 and Cd44 were not detected. Besides, they showed typical functional characteristics of MSCs such as fibroblast‐like morphology, plastic adherence, high proliferative capacity, clone formation in vitro and the ability to differentiate into chondrogenic, osteogenic and adipogenic lineages. We obtained for the first time an extensive characterization of undifferentiated cells populations contained in the bovine endometrium during the FP of the oestrous cycle. 相似文献
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Lunar surface magnetic fields and their interaction with the solar wind: results from lunar prospector 总被引：1，自引：0，他引：1
RP Lin DL Mitchell DW Curtis KA Anderson CW Carlson J McFadden MH Acuna LL Hood A Binder 《Science (New York, N.Y.)》1998,281(5382):1480-1484
The magnetometer and electron reflectometer experiment on the Lunar Prospector spacecraft has obtained maps of lunar crustal magnetic fields and observed the interaction between the solar wind and regions of strong crustal magnetic fields at high selenographic latitude (30 degreesS to 80 degreesS) and low ( approximately 100 kilometers) altitude. Electron reflection maps of the regions antipodal to the Imbrium and Serenitatis impact basins, extending to 80 degreesS latitude, show that crustal magnetic fields fill most of the antipodal zones of those basins. This finding provides further evidence for the hypothesis that basin-forming impacts result in magnetization of the lunar crust at their antipodes. The crustal magnetic fields of the Imbrium antipode region are strong enough to deflect the solar wind and form a miniature (100 to several hundred kilometers across) magnetosphere, magnetosheath, and bow shock system. 相似文献
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Procambarus clarkii Girard as a vector for the crayfish plague fungus, Aphanomyces astaci Schikora 总被引：1，自引：0，他引：1
Abstract. Procambarus clarkii Girard, a native freshwater crayfish species of Lousiana, USA, was found to harbour the crayfish plague fungus, Aphanomyces astaci Schikora, in its cuticle as a benign infection. Under certain conditions, P. clarkii dies as a result of this parasite, and the A. astaci infection then becomes acute and can be transmitted to Astacus astacus (L.).
Therefore, it is now shown that at least three different species of North American crayfish ( Pacifastacus leniusculus Dana, Orconectes limosus Raff, and Procambarus clarkii Girard) can carry the crayfish plague fungus, A. astaci , can transfer the disease to other crayfish species, and under certain circumstances can die of its own infection. 相似文献
Therefore, it is now shown that at least three different species of North American crayfish ( Pacifastacus leniusculus Dana, Orconectes limosus Raff, and Procambarus clarkii Girard) can carry the crayfish plague fungus, A. astaci , can transfer the disease to other crayfish species, and under certain circumstances can die of its own infection. 相似文献
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Soil structure is a dynamic property affected by physical, chemical, and microbiological processes. Addition of organic matter to soils and the use of different management practices have been reported to impact soil structure and crop production. Moderation in soil temperature and increases in microbial activity and soil water retention are often suggested as reasons for the rise in crop yield when organic matter is added to the soil. Less is known about the direct effect of changes in soil structure on crop production. A field experiment was conducted to study the effect of summer cover crop and in-season management system on soil structure. The experiment was a nested design with summer cover crop as the main plot and management system as the subplot. Summer cover crop treatments included cowpea (Vigna unguiculata L. Walp.) incorporated into the soil in the fall (CI), cowpea used as mulch in the fall (CM), sudangrass (Sorghum vulgare) incorporated into the soil in the fall (S), and dry fallow or bare ground (B). Management systems were organic (ORG) and conventional (CNV) systems. Lettuce (Lactuca sativa L.) and cantaloupes (Cucumis melo L.) were cultivated in rotation in the plots for three consecutive years using the same cover crops and management systems for each plot. Disturbed and undisturbed soil cores were collected at the end of the third year and used for laboratory experiments to measure physical, chemical, and hydraulic properties. Image analysis was used to quantify soil structure properties using a scanning electron microscope on thin sections prepared from the undisturbed soil cores. We found that total soil carbon was correlated with porosity, saturation percentage, and pore roughness. Pore roughness was correlated with crop production in general and with marketable production in particular. We found that the higher the complexity of the pore space, the more water retained in the soil, which may increase soil water residence and reduce plant water stress. 相似文献
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Our objective was to study reproductive consequences of lactation bodyweight loss occurring in primiparous sows with mild feed restriction and to relate these lactation weight losses and its consequences to metabolic profiles during lactation and subsequent early gestation. After weaning, 47 first‐litter sows were retrospectively assigned to a high– (HWL, >13.8%, n = 24) or low (LWL, ≤13.8%, n = 23)–weight loss group. Thirty‐six animals received an indwelling jugular vein catheter to determine lactational and gestational profiles of insulin‐like growth factor‐1 (IGF‐1), non‐esterified fatty acids (NEFA) and urea and gestational profiles of progesterone. At day 35 after insemination, sows were euthanized and their reproductive tract collected. Pregnancy rate was 75% (18/24) for HWL and 96% (22/23) for LWL sows. High–weight loss sows had a lower number of implantation sites (17.2 ± 0.8 vs 19.5 ± 0.7, respectively, p = 0.03) and a lower embryonic survival (65.6 ± 3.4 vs 77.4 ± 2.9%, p = 0.02), resulting in fewer vital embryos (14.9 ± 0.9 vs 16.8 ± 0.7, p = 0.07) than LWL sows. Progesterone peak values were reached later in HWL than in LWL sows (day 13.4 ± 0.5 vs 12.0 ± 0.5, respectively, p = 0.05). Gestational concentrations of IGF‐1, NEFA and urea were almost identical for HWL and LWL sows, whilst numerical differences were seen during lactation. The current study shows negative consequences of lactational weight loss in mildly feed‐restricted primiparous sows for embryonic survival and shows that these consequences seem only mildly related with metabolic alterations during lactation and not with metabolic alterations during subsequent gestation. 相似文献
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As part of a survey of patterns of disease in relation to air pollution in various towns, atmospheric concentrations of metals were measured in Armadale, West Lothian. The first survey of metallic pollutants in the environment consisted of measuring selected metal concentrations in indigenous Hypnum cupressiforme throughout Armadale. As in other surveys using this moss, Hypnum proved to be most useful in collecting at least 9 metals from the atmosphere. Some values, such as Fe, were significantly lower in Armadale, than those levels found in a similar survey sited around a steelworks in Consett, England. However, other metals such as Cu were present in much higher concentrations. All metals measured (apart from Pb values, which showed the influence of traffic routes) revealed an increasing concentration from the periphery of the town towards the vicinity of Armadale's steel foundry. 相似文献
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JR Strickland MA Custis AK Ashley LL Smith JL Klotz CR Krehbiel 《New Zealand veterinary journal》2013,61(5):288-292
AIM: To validate the use of para-aminohippuric acid (PAH) as a marker for measuring blood flow in wethers consuming a mixed diet of locoweed and blue grama hay. METHODS: Fourteen sheep, stratified by bodyweight (BW), were assigned to one of three treatments: 0.8 mg swainsonine (SW)/kg BW (HI), 0.2 mg SW/kg BW (LO), and no SW (Control). Sheep were fed various ratios of locoweed and blue grama hay to deliver SW treatments, for 28 days prior to infusion of PAH. Concentrations of SW and activities of alkaline phosphatase (Alk-P) and aspartate aminotransferase (AST) in serum were measured to confirm exposure to SW and subclinical intoxication. A single 20-ml injection of 5% PAH was delivered into the jugular vein after subclinical intoxication had been achieved. Blood samples were collected and serum analysed for PAH immediately prior to injection, then every 5 min from 5–30 min, and every 10 min from 30–60 min, following injection of PAH. RESULTS: Effective delivery of SW was evident from the greater concentrations of SW measured in the serum of HI compared with LO animals (p<0.05). No significant differences were detected in the rate of elimination (range 0.097–0.108 L/min), elimination half-life (range 6.62–7.24 min), apparent volume of distribution for the central compartment (range 7.14–9.72 L), and clearance (range 0.73–0.92 L/min) of PAH, between treatments. CONCLUSIONS: Subclinical intoxication with SW did not affect the pharmacokinetics of PAH. Thus, use of downstream dilution of PAH is a valid method to determine the rate of blood flow in nutrient flux experiments that involve consumption of locoweed. 相似文献