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101.
Martha L. Moon DVM MS Geoffrey K. Saunders DVM MS Robert A. Martin DVM 《Veterinary radiology & ultrasound》1990,31(1):39-41
A 5–year–old cat was presented for pelvic limb weakness. Sclerosis of the vertebral body of T–10 was visible on thoracic radiographs. A compressive lesion at this area was noted on myelography. A tumor was partially removed at surgery, but the cat was killed because of poor postoperative response. Rhabdomyosarcoma was diagnosed at necropsy, with bone marrow necrosis and myelofibrosis, and new bone proliferation of the body of T–10. Causes of bone necrosis are discussed. 相似文献
102.
The development of infectiological diagnostic methodology is characterized by saltatoric, revolutionary leaps. Improved sensitivity and specificity, reduction of analytical sample volumes, increased sample throughput, reduced test complexity associated with improved user friendliness are hallmarks of such developments. Apart from purely technical amenities some innovations also enable conceptual adaptations of monitoring strategies. These include the use of diagnostic assays on-site, e. g. in the stable or in the practice. Selecting the assay which is most "fit-for-purpose" among the plethora of sometimes loudly advertised new technology may be difficult even for the well trained and experienced diagnostician. Standardized licensing procedures for infectiological diagnostic kits may be required to guarantee minimal norms of diagnostic quality. At the same time availability of a diversity of diagnostic kits is needed to broaden the base of diagnostic reliability. New infectiological diagnostic innovations will only be useful if the (expanded) results are transposable to the improved practical care of companion animals and farm animal holdings. In addition, the judgment of results, e. g. for epidemiological plausibility, remains a very important issue even when the test results have been produced by novel high technology diagnostics. 相似文献
103.
Martin Bonamy Sabrina Kluska Elisa Peripolli Marcos Vinícius Antunes de Lemos Sabrina Thaise Amorim Roberto Jose Vaca Raysildo Barbosa Lbo Letícia Mendes de Castro Carina Ubirajara de Faria Fabio Borba Ferrari Fernando Baldi 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2019,136(1):15-22
The aim of this study was to estimate genetic parameters for different precocious calving criteria and their relationship with reproductive, growth, carcass and feed efficiency in Nellore cattle using the single‐step genomic BLUP. The reproductive traits used were probability of precocious calving (PPC) at 24 (PPC24), 26 (PPC26), 28 (PPC28) and 30 (PPC30) months of age, stayability (STAY) and scrotal circumference at 455 days of age (SC455). Growth traits such as weights at 240 (W240) and 455 (W455) days of age and adult weight (AW) were used. Rib eye area (REA), subcutaneous fat thickness (SFT), rump fat thickness (RFT) and residual feed intake (RFI) were included in the analyses. The estimation of genetic parameters was performed using a bi‐trait threshold model including genomic information in a single‐step approach. Heritability for PPC traits was moderate to high (0.29–0.56) with highest estimates for PPC24 (0.56) and PPC26 (0.50). Genetic correlation estimates between PPC and STAY weakened as a function of calving age. Correlation with SC455, growth and carcass traits were low (0.25–0.31; ?0.22 to 0.04; ?0.09 to 0.18, respectively), the same occurs with RFI (?0.09 to 0.08), this suggests independence between female sexual precocity and feed efficiency traits. The results of this study encourage the use of PPC traits in Nellore cattle because the selection for such trait would not have a negative impact on reproductive, growth, carcass and feed efficiency indicator traits. Stayability for sexual precocious heifers (PPC24 and PPC26) must be redefined to avoid incorrectly phenotype assignment. 相似文献
104.
Nicola Schmucker Urs Schatzmann PROF Katrin Budde DR Martin Gundel DR Christoph E. Jáuggin Hans Peter Meier DR 《Veterinary radiology & ultrasound》2000,41(2):168-171
The aim of this study was to determine the blood flow in the carotid artery during halothane anaesthesia by means of duplex-sonography. Seventeen warm blood horses were evaluated in dorsal and lateral recumbency and the results were compared with the values of the same horses resting and under sedation. The cross sectional area of the vessels, the time-averaged maximal blood velocity, time-averaged maximal blood flow and the resistance index were determined and the flow profile was evaluated. During halothane anesthesia the total blood flow shows a significant increase which is not dependent on the positioning of the horse. Mean blood velocity is decreased by sedation and significantly increased during anesthesia. Reduced peripheral resistance is expressed by a decline of the resistance index. After sedation and during recumbency there is an increase in diameter of the carotid artery. 相似文献
105.
A path model of factors influencing morbidity and mortality in Ontario feedlot calves. 总被引:1,自引:1,他引:1 下载免费PDF全文
The principles of path analysis and causal modelling are discussed. Path analysis was applied to three data sets to assess the relationship between group characteristics (number per group and "mixing" subgroups of cattle, feeding-management of the group and processing factors (vaccination and prophylactic antimicrobials) and subsequent morbidity and mortality in feedlot cattle. The major findings agree with previously reported results but the timing and pathways of the effects are elaborated. In general, morbidity in week 1 was correlated with morbidity in week 2, which was correlated with morbidity in weeks 3-5. The same was generally true for mortality. In general, morbidity was not strongly correlated with mortality. Lots (unmixed groups) did not arrive in better condition, but experienced fewer subsequent health problems than mixed groups. (Silage-fed lots appeared to do poorly, however this was apparently due to the positive association between lots and vaccination, the latter being detrimental to mortality rates.) The more cattle per group, the greater the health problems in weeks 3-5 postarrival. Prophylactic antimicrobials in the water supply on arrival lead to increased health problems in the three to five week postarrival period. Antibiotic containing starter rations had a beneficial effect on health status in this period. This effect appeared to be partly due to delaying making silage the major ration component in silage-fed cattle receiving antimicrobial containing starter rations. Vaccination against respiratory disease in either of the first two weeks postarrival had detrimental direct and indirect effects on subsequent health status. Vaccination during weeks 3-5 postarrival was not significantly related to health status in that period. 相似文献
106.
D L Zoran A E Jergens D H Riedesel G S Johnson T B Bailey S D Martin 《American journal of veterinary research》1992,53(10):1791-1796
The effects of hypertonic saline solution (HTSS) combined with colloids on hemostatic analytes were studied in 15 dogs. The analytes evaluated included platelet counts, one-stage prothrombin time, activated partial thromboplastin time, von Willebrand's factor antigen (vWf:Ag), and buccal mucosa bleeding times. The dogs were anesthetized, and jugular phlebotomy was used to induced hypovolemia (mean arterial blood pressure = 50 mm of Hg). Treatment dogs (n = 12) were resuscitated by infusion (6 ml/kg of body weight) of 1 of 3 solutions: HTSS combined with 6% dextran 70, 6% hetastarch, or 10% pentastarch. The control dogs (n = 3) were autotransfused. Hemostatic analytes were evaluated prior to induction of hypovolemia (baseline) and then after resuscitation (after 30 minutes of sustained hypovolemia) at 0.25, 0.5, 1, 6 and 24 hours. All treatment dogs responded rapidly and dramatically to resuscitation with hypertonic solutions. Clinically apparent hemostatic defects (epistaxis, petechiae, hematoma) were not observed in any dog. All coagulation variables evaluated, with the exception of vWf:Ag, remained within reference ranges over the 24-hour period. The vWf:Ag values were not statistically different than values from control dogs, and actual values were only slightly lower than reference ranges. Significant (P < or = 0.04) differences were detected for one-stage prothrombin time, but did not exceed reference ranges. The results of this study suggested that small volume HTSS/colloid solutions do not cause significant alterations in hemostatic analytes and should be considered for initial treatment of hypovolemic or hemorrhagic shock. 相似文献
107.
Y Gu A P Schinckel T G Martin J C Forrest C H Kuei L E Watkins 《Journal of animal science》1992,70(6):1708-1718
Carcasses of 181 barrows, representing five genotypes, 1) H x HD, 2) SYN, 3) HD x L[YD], 4) L x YD, and 5) Y x L (H = Hampshire, D = Duroc, SYN = synthetic terminal sire line, L = Landrace, and Y = Yorkshire), and two levels of ractopamine (RAC) treatment (0 and 20 ppm) were completely dissected and the data were used to examine genotype and treatment (RAC) biases in estimation of fat-standardized lean weight and to evaluate accuracies and precisions realized by use of equations based on variables derived from different technologies. Independent variables used to establish regression equations represented technologies of direct carcass measurements, optical probe data, TOBEC (total body electrical conductivity) readings, and dissected (DHMLN) and fat-standardized (FSHMLN) ham lean. Genotype bias existed when any equation from a single technology was used and was minimized by combining FSHMLN with one TOBEC reading, carcass length, and the probe measurement of 10th rib fat depth. Large RAC biases appeared when equations from direct carcass measurements or optical probe data were used and were minimized by an equation using either DHMLN or FSHMLN. A practical equation with relatively high R2 value and small genotype and RAC biases were developed by combining TOBEC readings with direct carcass measurements of 10th rib fat depth and warm carcass weight. 相似文献
108.
Unrecognized diversity in New Guinean crayfish species (Decapoda,Parastacidae): The evidence from molecular data 下载免费PDF全文
The phylogenetic relationships among imported ornamental crayfish belonging to the genus Cherax were inferred from a combined dataset of 3 mitochondrial genes (COI, 16S and 12S) and by comparison with available GenBank sequences of 14 Cherax species. Furthermore, the concordance of previously described species obtained from a wholesaler (Cherax boesemani, C. holthuisi and C. peknyi) with available GenBank sequences was verified based on COI with special respect to comparison with sequences assigned as Cherax species. Recently described species C. gherardiae, C. pulcher and C. subterigneus belong to the northern group of Cherax species. Comparison and analysis with other GenBank COI sequences show previously unreported diversity of New Guinean species, suggesting 5 putative new species. Surprisingly, species assigned to the subgenus Astaconephrops do not form a monophyletic clade; this subgenus should be reappraised relative to the purported typical morphological characteristic of the uncalcified patch on male chelae. Increasing importation of crayfish underscores the importance of accurate species identification. Use of basic molecular methods is a necessary requisite for documenting occurrence, abundance and population trends of target species. Consequently, it helps to support eventual conservation decision‐making by stakeholders. 相似文献
109.
We describe the spatial epidemiological features of the 6.8 million meat-juice serological tests that were conducted between 1995 and 2004 as part of the Danish swine Salmonella control programme. We investigated pig and farm density using edge-corrected kernel estimations. Pigs were aggregated at the county level to assess county-level risk, and then we investigated farm-level risk by giving farms a case or non-case label using a cut-off of 40% of pigs positive. Conditional probability surfaces, correcting for the underlying population at risk, were produced for each year of the study period using a novel kernel estimator with a spatially adaptive smoothing bandwidth. This approach improves on previous methods by allowing focussed estimation of risk in areas of high population density while maintaining stable estimates in regions where the data are sparse. Two spatial trends in the conditional probability of a farm being a case were evident: (1) over the whole country, with the highest risk in the west compared to the east; and (2) on the Jutland peninsula with the highest risk in the north and south. At the farm-level a consistent area of risk was the south-west of Jutland. Case farms tended to aggregate indicating spatial dependency in the data. We found no association between pig or farm density and Salmonella risk. We generated hypotheses for this spatial pattern of risk and we conclude that this spatial pattern should be considered in the development of surveillance strategies and as a basis for further, more detailed analyses of the data. 相似文献
110.