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Search for Lawsonia intracellularis and Bilophila wadsworthia in malabsorption-diseased chickens Полный текст
2003
McOrist, Steven | Keller, Linda | McOrist, Alexandra L.
Proliferative enteropathy is an important enteric disease caused by Lawsonia intracellularis. A wide range of host species can be infected by the same bacterium, yet the clinico-pathologic features among these hosts remains almost identical. The disease has been recognized regularly among ratites, but not in other avian families, such as galliforms, even though these suffer uncharacterized enteric conditions. Fresh ileum-colon contents were obtained from 228, 3- to 8-week-old chickens with enteric disease, kept at 14 large commercial farms in the southern USA. DNA was extracted from each sample and subjected to polymerase chain reactions (PCR) with primers specific to eubacterial DNA, L. intracellularis, and Bilophila wadsworthia. All chicken samples were positive for eubacterial DNA, 29 chickens (13%) were positive for B. wadsworthia DNA, and none were positive for L. intracellularis DNA. Given the ubiquitous nature of L. intracellularis, we consider it likely that some avian families do not carry the necessary mechanism for L. intracellularis viability. Bilophila wadsworthia appears to be a consistent member of the colonic flora of some host animals. Neither bacterium appears to be associated with malabsorption syndromes in chickens.
Показать больше [+] Меньше [-]Kinetics and postmucosal effects on urinary recovery of 5 intravenously administered sugars in healthy cats Полный текст
2003
Krecic, Matthew R. | Steiner, Jörg M. | Kern, Margaret R. | Williams, David A.
The objective of this study was to describe the kinetics of urinary recovery and to evaluate the effects of postmucosal factors on urinary recovery of 5 intravenously administered saccharides. Ten cats received an isotonic sugar solution containing lactulose, rhamnose, xylose, methylglucose, and sucrose intravenously. These sugars were selected because of their prior use for intestinal permeability and mucosal function testing in humans and dogs. Urethral catheterization with a closed collection system was used for collection of cumulative urine samples prior to and 2, 4, 6, 8, 10, 12, and 24 h after administration of the sugar solution. High-pressure anion exchange liquid chromatography with pulsed amperometric detection was used to measure the concentrations of each sugar in the urine and calculate urinary recovery. Twenty-four hour cumulative urinary recovery for each sugar from the cats, was lower than expected compared to dogs and humans. All 5 sugars had the highest percentage of urinary recovery during the first 2 h after administration. Mean sugar elimination rate constants and half-lives ranged from 0.268/h for methylglucose to 0.415/h for lactulose and 1.67 h for lactulose to 2.59 h for methylglucose, respectively. Metabolism and incomplete urine collection are possible reasons for lower cumulative urinary recoveries of these 5 sugars in cats compared with dogs. Although these 5 sugars are not ideal marker molecules, they may still be useful for intestinal permeability and mucosal function testing in cats.
Показать больше [+] Меньше [-]Epidemiologic study of results of pulsed-field gel electrophoresis of isolates of Rhodococcus equi obtained from horses and horse farms Полный текст
2003
Cohen, Noah D. | Smith, Karen E. | Ficht, Thomas A. | Takai, Shinji | Libal, Melissa C. | West, Brian R. | DelRosario, Lemuel S. | Becu, Teotimu | Leadon, Desmond P. | Buckley, Thomas C. T. | Chaffin, M Keith | Martens, Ronald J.
Objective-To compare isolates of Rhodococcus equi on the basis of geographic source and virulence status by use of pulsed-field gel electrophoresis (PFGE). Sample Population-290 isolates of R equi(218 virulent isolates from foals and 72 avirulent isolates from feces, soil, and respiratory tract samples) obtained between 1985 and 2000 from horses and horse farms from 4 countries. Procedure-DNA from isolates was digested with the restriction enzyme AseI and tested by use of PFGE. Products were analyzed for similarities in banding patterns by use of dendrograms. A similarity matrix was constructed for isolates, and the matrix was tested for nonrandom distributions of similarity values with respect to groupings of interest. Results-There was little grouping of isolates on the basis of country, virulence status, or region within Texas. Isolates of R equi were generally < 80% similar, as determined by use of PFGE. Isolates from the same farm generally were rarely of the same strain. Conclusions and Clinical Relevance-Considerable chromosomal variability exists among isolates of R equi obtained from the same farm, sites within Texas, or among countries from various continents. Only rarely will it be possible to link infections to a given site or region on the basis of analysis of isolates by use of PFGE of chromosomal DNA.
Показать больше [+] Меньше [-]Effect of oocyte quality on the relative abundance of specific gene transcripts in bovine mature oocytes and 16-cell embryos Полный текст
2003
Bilodeau-Goeseels, Sylvie
Although the developmental potential of oocytes is related to oocyte quality, whether the expression of specific genes is altered in oocytes of different quality and in resulting embryos is not known. Semi-quantitative reverse transcription-polymerase chain reaction was used to compare the relative abundance of 2 transcripts for housekeeping proteins (β-actin and ribosomal protein L30) and 3 transcripts for growth factor ligand or receptors (platelet derived growth factor receptor α (PDGFRα), basic fibroblast growth factor (bFGF)), in mature bovine oocytes of high versus low developmental potential. The transcripts for L30, PDGFRα, and bFGF in 16-cell embryos originating from these oocytes were also examined. No significant effect of oocyte quality was detected for any of the transcripts examined from oocytes or 16-cell embryos. In conclusion, a lower developmental potential of oocytes with advanced signs of atresia, was not associated with a lower level of abundance of the transcripts examined.
Показать больше [+] Меньше [-]Effects of exercise and glucose administration on content of insulin-sensitive glucose transporter in equine skeletal muscle Полный текст
2003
Lacombe, Véronique A. | Hinchcliff, Kenneth W. | Devor, Stephen T.
Objective-To characterize insulin-sensitive glucose-transporter (GLUT-4) protein in equine tissues and determine effects of exercise and glucose administration on content of GLUT-4 protein in equine skeletal muscle. Sample Population-Tissue samples from 9 horses. Procedure-Western blot analyses were performed on crude membrane preparations of equine tissues to characterize GLUT-4. In a crossover, randomized study, horses were strenuously exercised for 3 consecutive days and then administered 13.5% glucose or isotonic saline (0.9% NaCl; control) solution, IV, at similar infusion rates for 12.1 hours. Samples were collected from the middle gluteal muscle before and after exercise and 10.1 hours after completion of an infusion and used for measurements of glycogen concentration and total content of GLUT-4 protein. Results-Immunoblot analyses detected specifically immunoreactive bands for GLUT-4 in insulin-sensitive tissues. Content of GLUT-4 protein in skeletal muscle increased significantly by 27.3 and 12.3% 22.2 hours after exercise for control and glucose groups, respectively. Intravenous infusion of glucose resulted in a significantly higher rate of glycogenesis, compared with results for the control group (mean +/- SD, 3.98 +/- 0.61 and 1.47 +/- 0.20 mmol/kg/h, respectively). Despite enhanced glycogenesis, we did not detect an increase in content of GLUT-4 protein after glucose infusion, compared with values after exercise. Conclusions and Clinical Relevance-GLUT-4 protein was expressed in equine skeletal and cardiac muscles. Exercise increased total content of GLUT-4 protein in skeletal muscle, and replenishment of muscle glycogen stores after glucose infusion attenuated the exercise-induced increase in the content of GLUT-4 protein in equine skeletal muscle.
Показать больше [+] Меньше [-]Analgesic and systemic effects of ketamine, xylazine, and lidocaine after subarachnoid administration in goats Полный текст
2003
DeRossi, Rafael | Junqueira, Alexandre Lopes | Beretta, Marcelo Paixão
Objective-To determine the effects of ketamine hydrochloride, xylazine hydrochloride, and lidocaine hydrochloride after subarachnoid administration in goats. Animals-6 healthy goats. Procedure-In each goat, ketamine (3 mg/kg), xylazine (0.1 mg/kg), lidocaine (2.5 mg/kg), and saline (0.9% NaCl) solution were injected into the subarachnoid space between the last lumbar vertebra and first sacral vertebra (time 0). Analgesic, ataxic, sedative, cardiovascular, and respiratory effects and rectal temperature were evaluated before (baseline) and 2, 5, 10, 15, and 30 minutes after administration and at 30-minute intervals thereafter as needed. Results-Administration of anesthetics induced varying degrees of analgesia. Onset of the analgesic effect was more delayed for xylazine (mean +/- SD, 9.5 +/- 2.6 minutes) than for ketamine (6.7 +/- 2.6 minutes) or lidocaine (3.5 +/- 1.2 minutes). Duration of analgesia induced by xylazine (88.3 ± 15 minutes) was twice as long as the duration of analgesia induced by ketamine (48.8 ± 13.5 minutes) but similar to that induced by lidocaine (66.5 ± 31 minutes). Xylazine induced bradycardia, whereas ketamine caused a nonsignificant increase in heart rate. Xylazine induced a reduction in arterial pressure, whereas ketamine or lidocaine did not affect arterial pressure. Conclusion and Clinical Relevance-Subarachnoid administration of xylazine in goats resulted in longer duration of analgesia of the tail, perineum, hind limbs, flanks, and caudodorsal rib areas than administration of ketamine or lidocaine. However, xylazine caused bradycardia and respiratory depression. Additional studies are needed to determine whether the analgesia would be sufficient to allow clinicians to perform surgical procedures.
Показать больше [+] Меньше [-]Biocompatibility of three-dimensional chondrocyte grafts in large tibial defects of rabbits Полный текст
2003
Cook, James L. | Harbin, Robert | Kreeger, John M. | Peacock, John T. | Tomlinson, James L.
Objective-To evaluate biocompatibility and effects of implantation of 3-dimensional chondrocyte-agarose autografts in tibial defects in rabbits and to compare in vitro and in vivo chondrocyte-agarose constructs with respect to cell viability, differentiation, and matrix production. Animals-24 adult New Zealand White rabbits. Procedure-Three-dimensional constructs with (grafted group) or without (control group) autogenous chondrocytes were implanted into tibial defects of rabbits and cultured in vitro. During an 8-week period, defects were evaluated radiographically, grossly, histologically, biochemically, and immunohistochemically. In vitro constructs were evaluated histologically, biochemically, and immunohistochemically. Results-Tibial defects had significantly higher radiographic densitometry values at 4 and 6 weeks after implantation in grafted group rabbits, compared with control group rabbits. Number of observed centers of endochondral ossification was significantly greater in defects of grafted group rabbits, compared with control group rabbits. On day 14, glycosaminoglycan concentration was significantly higher in tibial defects of grafted group rabbits, compared to defects of control group rabbits or in vitro constructs. At weeks 2, 4, and 8, glycosaminoglycan concentrations were significantly lower in the in vitro control constructs, compared with other groups. Collagen type I was present in bone and bony callous in defects of grafted and control group rabbits. Collagen type II was identified in cartilaginous tissues of grafted and control group rabbits. Collagen type X was associated with hypertrophic chondrocytes. Only type II collagen was found in the in vitro chondrocyte constructs. Conclusion and Clinical Relevance-Chondrocyte-agarose grafts are biocompatible in large tibial defects and appear to provide a cell source for augmenting endochondral ossification.
Показать больше [+] Меньше [-]Serum C-reactive protein in dairy herds Полный текст
2003
Lee, Wen-Chuan | Hsiao, Huo-Cheng | Wu, Ying-Ling | Lin, Jyh-Hung | Lee, Yen-Pai | Fung, Hang-Poung | Chen, Hsin-Hsin | Chen, Yu-Hsin | Chu, Rea-Min
The purpose of this study was to determine the relationship between the serum level of C-reactive protein (CRP) and lactation and health status. Blood samples were collected every 2 wk for 12 mo from 29 randomly selected dairy cattle on 3 farms. At the time the blood samples were collected, the stage of pregnancy, lactation status, breeding records, general health condition, reproductive status, and body condition score were recorded for each cow. Serum CRP was detected with sodium dodecyl sulfate polyacrylamide gel electrophoresis and western immunoblotting. C-reactive protein levels were measured with a densitometer and expressed as an optimal dose value. C-reactive protein levels were correlated with the body condition score, lactation status, and animal health (P < 0.05), but not with ambient temperature, animal age, or parity. C-reactive protein levels increased with milk production, peaking during high lactation (2 to 4 mo of pregnancy), and decreased when lactation ceased. In addition, the CRP level was highest during naturally occurring infections, such as mastitis and other tissue inflammation. Thus, the CRP level can confirm the presence of inflammation. The stress effect of taking blood samples as measured by the CRP level, was also examined. The CRP level became rapidly elevated 12 h after the blood samples were taken but returned to normal 36 h later. In conclusion, the stresses resulting from overall poor health, heavy lactation, and blood sampling caused the elevation of serum CRP. C-reactive protein is a marker or tool for evaluating the health status of a herd. C-reactive protein should also be considered as a useful criteria to assess the stress levels and may be useful in early surveillance of disease conditions in a dairy herd.
Показать больше [+] Меньше [-]Multiplex nested PCR compared with in situ hybridization for the differentiation of porcine circoviruses and porcine parvovirus from pigs with postweaning multisystemic wasting syndrome Полный текст
2003
Kim, Junghyun | Chae, Chanhee
Multiplex nested polymerase chain reactions (PCRs) were developed for the simultaneous detection and differentiation of genomic material of porcine circovirus 1 (PCV1), porcine circovirus 2 (PCV2), and porcine parvovirus (PPV) in formalin-fixed, paraffin-embedded tissues. Multiplex conventional and nested PCR and in situ hybridization were compared for their ability to detect the 3 viruses in such tissues. Xylene deparaffinization followed by proteinase K digestion yielded DNA of sufficient quality for reliable and consistent PCR analyses. The DNA from PCV1, PCV2, and PPV was detected by both multiplex nested PCR and in situ hybridization in lymph-node tissue from 12 pigs experimentally co-infected with the 3 viruses, as well as in formalin-fixed, paraffin-embedded lymph-node tissue from 30 pigs with naturally occurring postweaning multisystemic wasting syndrome; the agreement rates for the 2 methods were 100% in both groups of pigs. Thus, multiplex nested PCR could be applied successfully to formalin-fixed, paraffin-embedded tissues for simultaneous detection of these 3 porcine viruses.
Показать больше [+] Меньше [-]Use of a 13C-aminopyrine blood test: first clinical impressions Полный текст
2003
Chiaramonte, Deirdre | Steiner, Jörg M. | Broussard, John D. | Baer, Keith | Gumminger, Sheila | Moeller, Erik M. | Williams, David A. | Shumway, Renée
The purpose of this study was to collect initial data to determine the potential clinical usefulness of a 13C-aminopyrine demethylation blood test, and whether additional clinical investigation is warranted. Six dogs, initially suspected of having hepatic disease based on their history, physical examination, imaging studies, general laboratory parameters, or any combination of the above, were enrolled in the study. A baseline blood sample was collected, 2 mg/kg 13C-aminopyrine was administered intravenously, and another blood sample was collected 45 min afterwards. Carbon dioxide was extracted from the blood samples and analyzed using fractional mass spectrometry. Results from the 13C-aminopyrine demethylation blood test were compared to clinical data and histologic findings. Intravenous administration of 13C-aminopyrine leads to a decrease in the percent dose of 13C recovered from dogs with histologically confirmed liver disease. Based on our results, a full-scale investigation of the potential clinical usefulness of a 13C-aminopyrine demethylation blood test for assessment of hepatic function in dogs is warranted.
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