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91.
Identification on commercialized products of AFLP markers able to discriminate slow- from fast-growing chicken strains 总被引:2,自引:0,他引:2
Fumière O Dubois M Grégoire D Théwis A Berben G 《Journal of agricultural and food chemistry》2003,51(5):1115-1119
The European chicken meat market is characterized by numerous quality marks: "Label de Qualité Wallon" in Belgium, "Label Rouge" in France, denominations of geographical origin, organic agriculture, etc. Most of those certified productions have specifications requiring the use of slow-growing chicken strains. The amplified fragment length polymorphism (AFLP) technique has been used to search molecular markers able to discriminate slow-growing chicken strains from fast-growing ones and to authenticate certified products. Two pairs of restriction enzymes (EcoRI/MseI and EcoRI/TaqI) and 121 selective primer combinations were tested on individual DNA samples from chicken products essentially in carcass form that were ascribed as belonging to either slow- or fast-growing strains. Within the resulting fingerprints, two fragments were identified as type-strains specific markers. One primer combination gives a band (333 bp) that is specific for slow-growing chickens, and another primer pair generates a band (372 bp) that was found to be characteristic of fast-growing chickens. The two markers were isolated, cloned, and sequenced. The effectiveness and the specificity of the two interesting determinants were assessed on individuals of two well-known strains (ISA 657 and Cobb 500) and on commercialized products coming from various origins. 相似文献
92.
Alwyn Sowerby Bridget Emmett Albert Tietema Marc Estiarte Steven Hughes 《Soil biology & biochemistry》2005,37(10):1805-1813
Climate change constitutes a serious threat for European heathlands as unlike other sources of damage, such as over-grazing, local remediation is not a possibility. Within the large pan-European projects, CLIMOOR and VULCAN, the effect of periodic drought and increased temperature were investigated in four heathland ecosystems along a geographical and climatic gradient across Europe. Fluorogenically labelled substrates for four enzymes (glucosidase, sulphatase, phosphatase, leucine amino peptidase) were used to measure extra-cellular enzyme activity in soil samples from each of the CLIMOOR sites. Microbial extra-cellular enzyme production is linked to microbial activity as well as soil physico-chemical properties, making soil enzymes one of the more reactive components of terrestrial ecosystems and potentially excellent indicators of soil microbial functional status and diversity.Across all sites and over all the substrates, organic matter content was exponentially, inversely related to enzyme activity. Although the increase in temperature produced by the CLIMOOR roofs was small (on average 0.9 °C), this was sufficient to increase enzyme activity in all sites (on average by 45%). The increase was within the range of seasonal variability at each of the sites. The effect of drought on enzyme activity was more pronounced in the Northern European sites than the southern European, and most moisture limited, site. This suggests that the effect of temperature increases may be observed across all regions; however, the soils of northern Europe may be more sensitive to changes in rainfall patterns than more moisture limited Southern European soils. 相似文献
93.
Seasonal patterns of root-surface phosphatase activities in a Mediterranean shrubland. Responses to experimental warming and drought 总被引:2,自引:0,他引:2
Mediterranean ecosystems are water limited and the current general circulation Models (GCM) and ecophysiological models forecast
a warming and a further increase of drought in the next decades. A stronger water stress can decrease the capacity for nutrient
absorption by plants. We conducted a field experiment to simulate forecasted drought and warming in a Mediterranean calcareous
shrubland to assess the performance of root-surface phosphatase activities of the dominant shrub Globularia alypum. These enzyme activities were higher in autumn and spring, when the climate conditions were optimal for plant activity, than
in summer or winter, when there was either lack of water or cold temperatures. A decrease in soil moisture in drought plots
decreased root-surface phosphatase activity (29% in summer and 25% in autumn). The decrease in root-surface phosphatase activity
in drought plots coincided with a decrease in P leaf concentrations and P accumulation in aboveground biomass and loss of
photosynthetic capacity of some dominant shrub species of this ecosystem, and with a tendency to increase total soil-P. These
results suggest that the expected drier conditions in this Mediterranean shrubland in the next decades will slow down the
P uptake by plants, thereby, diminishing the P contents in biomass and increasing total P contents in soil in non-available
forms and that this can be, in part, attributable to a result of the decrease in root-surface phosphatase activity. 相似文献
94.
95.
Little AA Steffey M Kraus MS 《Journal of the American Animal Hospital Association》2007,43(3):157-162
A 16-month-old, female German shepherd dog was presented with severe bicavitary effusions. A diaphragmatic hernia was diagnosed by thoracic radiography. An echocardiogram performed prior to surgical repair of the hernia revealed signs of cardiac tamponade, with right atrial collapse, in the absence of pericardial effusion. Right atrial collapse was presumed to be secondary to severe pleural effusion. At surgery, no pericardial disease was identified. Surgical correction of the diaphragmatic hernia resulted in resolution of the pleural and peritoneal effusions. Follow-up echocardiography demonstrated resolution of the signs of cardiac tamponade. 相似文献
96.
Christine Kreuder Jonna A K Mazet Gregory D Bossart Tim E Carpenter Marcel Holyoak Marc S Elie Scott D Wright 《Journal of zoo and wildlife medicine》2002,33(1):8-15
Outbreaks of morbidity and mortality in double-crested cormorants (Phalacrocorax auritus) along Florida's Gulf Coast have occurred sporadically for at least 30 yr. During these outbreaks, the Clinic for the Rehabilitation of Wildlife, located on Sanibel Island in Florida, has admitted a substantial number of cormorants with consistent presentation of primarily neurologic clinical signs. In order to investigate the association of these outbreaks in cormorants with exposure to brevetoxin, we compared the timing of admittance of cormorants with outbreak-specific clinical signs to blooms of the brevetoxin-producing marine algae, Karenia brevis (formerly Gymnodinium breve), around Sanibel Island from 1995 through 1999. The clinic admitted 360 out of 613 cormorants with the common clinical sign of severe cerebellar ataxia in six outbreaks occurring during this period. The ataxia was characterized by a broad-based stance, truncal incoordination, hypermetric gait, and intention tremors of the head. The histopathologic findings in 10 cormorants euthanized in 1997 were mild and nonspecific. An immunohistochemical staining technique for the detection of brevetoxin in cormorants documented the uptake of brevetoxin in tissues from four cormorants admitted during an outbreak in 1997, but a modified technique used on samples from 11 cormorants admitted during a K. brevis bloom in 2000 produced indeterminate results. Admittance of cormorants with outbreak-specific clinical signs was positively correlated (P < 0.05) with concurrent concentrations of K. brevis in local water. The cross-correlation coefficient was also significant when increased K. brevis levels preceded cormorant admittances by 2, 4, 6, and 8 wk. This delay in time between K. brevis blooms and cormorant admittance and our clinical finding of neurologic abnormalities in cormorants without overt histopathologic features suggest an association between K. brevis blooms and local cormorant morbidity. 相似文献
97.
Lisa J. Thompson DVM ; Ravi Seshadri DVM DACVECC DAVBP Marc R. Raffe DVM MS DACVA DACVECC 《Journal of Veterinary Emergency and Critical Care》2009,19(2):165-173
Objective – Describe clinical characteristics and outcomes associated with canine patients undergoing surgical intervention for treatment of acute pancreatitis.
Design – Retrospective outcome study from 2001 to 2007.
Animals – Thirty-seven dogs.
Interventions – None.
Measurements and Main Results – The following data were collected for dogs who underwent surgical intervention in the course of treatment for severe acute pancreatitis: preoperative clinicopathologic and physical data, ultrasonographic findings, surgical procedure detail, histopathologic findings, and transfusion requirements. The survival rate was 80.8% in dogs with extrahepatic biliary obstruction, 64.3% in dogs undergoing necrosectomy, and 40.6% with pancreatic abscess. Overall survival was 63.6%. Surgical complications included intraoperative and postoperative hemorrhage in 12 dogs, postoperative development of diabetes mellitus in 3 dogs, exocrine pancreatic insufficiency in 1 dog, and bacterial peritonitis in 2 dogs.
Conclusion – Surgical intervention and aggressive postoperative care may be pursued in select dogs with severe acute pancreatitis. In dogs with extrahepatic biliary obstruction secondary to acute pancreatitis, surgical intervention may be associated with a good prognosis whereas dogs with pancreatic abscess formation may have a more guarded prognosis. 相似文献
Design – Retrospective outcome study from 2001 to 2007.
Animals – Thirty-seven dogs.
Interventions – None.
Measurements and Main Results – The following data were collected for dogs who underwent surgical intervention in the course of treatment for severe acute pancreatitis: preoperative clinicopathologic and physical data, ultrasonographic findings, surgical procedure detail, histopathologic findings, and transfusion requirements. The survival rate was 80.8% in dogs with extrahepatic biliary obstruction, 64.3% in dogs undergoing necrosectomy, and 40.6% with pancreatic abscess. Overall survival was 63.6%. Surgical complications included intraoperative and postoperative hemorrhage in 12 dogs, postoperative development of diabetes mellitus in 3 dogs, exocrine pancreatic insufficiency in 1 dog, and bacterial peritonitis in 2 dogs.
Conclusion – Surgical intervention and aggressive postoperative care may be pursued in select dogs with severe acute pancreatitis. In dogs with extrahepatic biliary obstruction secondary to acute pancreatitis, surgical intervention may be associated with a good prognosis whereas dogs with pancreatic abscess formation may have a more guarded prognosis. 相似文献
98.
José Ramón González Antoni Trasobares Marc Palahí Timo Pukkala 《Annals of Forest Science》2007,64(7):733-742
The study developed models for predicting the post-fire tree survival in Catalonia. The models are appropriate for forest planning purposes. Two types of models were developed: a stand-level model to predict the degree of damage caused by a forest fire, and tree-level models to predict the probability of a tree to survive a forest fire. The models were based on forest inventory and fire data. The inventory data on forest stands were obtained from the second (1989–1990) and third (2000–2001) Spanish national forest inventories, and the fire data consisted of the perimeters of forest fires larger than 20 ha that occurred in Catalonia between the 2nd and 3rd measurement of the inventory plots. The models were based on easily measurable forest characteristics, and they permit the forest manager to predict the effect of stand structure and species composition on the expected damage. According to the stand level fire damage model, the relative damage decreases when the stand basal area or mean tree diameter increases. Conversely, the relative stand damage increases when there is a large variation in tree size, when the stand is located on a steep slope, and when it is dominated by pine. According to the tree level survival models, trees in stands with a high basal area, a large mean tree size and a small variability in tree diameters have a high survival probability. Large trees in dominant positions have the highest probability of surviving a fire. Another result of the study is the exceptionally good post-fire survival ability of Pinus pinea and Quercus suber. 相似文献
99.
Levine JM Levine GJ Boozer L Schatzberg SJ Platt SR Kent M Kerwin SC Fosgate GT 《Journal of the American Veterinary Medical Association》2008,232(3):411-417
OBJECTIVE: To determine complications and neurologic outcomes associated with dexamethasone administration to dogs with surgically treated thoracolumbar intervertebral disk herniation, compared with dogs not receiving dexamethasone. DESIGN: Retrospective case series. ANIMALS: 161 dogs with surgically confirmed thoracolumbar disk herniation. PROCEDURES: Medical records from 2 hospitals were used to identify dogs that had received dexamethasone < 48 hours prior to admission (dexamethasone group dogs), dogs that received glucocorticoids other than dexamethasone < 48 hours prior to admission (other-glucocorticoid group dogs), and dogs that received no glucocorticoids (nontreatment group dogs). Signalment, neurologic injury grade, laboratory data, and complications were extracted from medical records. RESULTS: Dexamethasone group dogs were 3.4 times as likely to have a complication, compared with other-glucocorticoid or nontreatment group dogs. Dexamethasone group dogs were 11.4 times as likely to have a urinary tract infection and 3.5 times as likely to have diarrhea, compared with other-glucocorticoid or nontreatment group dogs. No differences in neurologic function at discharge or recheck evaluation were detected among groups. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that treatment with dexamethasone before surgery is associated with more adverse effects, compared with treatment with glucocorticoids other than dexamethasone or no treatment with glucocorticoids, in dogs with thoracolumbar intervertebral disk herniation. In this study population, no difference in outcome was found among groups. These findings suggest that the value of dexamethasone administration before surgery in dogs with thoracolumbar disk herniation should be reconsidered. 相似文献
100.
Marijke Verhegghe Florence Crombé Larissa J Pletinckx Freddy Haesebrouck Patrick Butaye Lieve Herman Marc Heyndrickx Geertrui Rasschaert 《Veterinary research》2014,45(1)
During a previous longitudinal study, performed on four farrow-to-finish farms (A to D), samples were taken from twelve sows, their offspring, and the environment on various occasions over six months to study the MRSA presence. During the present study, a selection of the obtained MRSA isolates were typed by multiple-locus variable-number tandem-repeat analysis (MLVA), Pulsed Field Gel Electrophoresis (PFGE), spa typing, and SCCmec typing to study the genetic diversity of LA-MRSA isolates and to determine possible MRSA sources for pig(let)s. PFGE, spa typing, and SCCmec typing revealed the presence of one or few dominant genotype(s) per farm. In contrast, 212 MLVA types were detected on the four farms, forming one cluster on farm A, three on farm B, four on farm C and two on farm D. The genotype, found on farm A was unique for this farm. Farms B, C and D shared one cluster. In general, MLVA types from these clusters were isolated from piglets, sows, and the environment on various sampling events. Piglets carried MLVA types both related and unrelated to their mother sows’ MLVA types at farrowing and onwards. In conclusion, molecular typing revealed that within a farm one or a few dominant strain(s) are widespread. Potential MRSA sources for piglets were mother sows, the environment and other piglets.