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71.
72.
Standard culturing techniques are often unrewarding in confirming diagnosis of synovial infection in the equine patient. Several human studies report the use of sensitive polymerase chain reaction (PCR) techniques for the detection of bacterial involvement in acute synovitis. However, successful extraction of bacterial DNA directly from clinical samples from horses without prior culture has not been reported yet. The goal of this study was to develop a sensitive and reliable method for molecular detection and identification of bacterial species in synovial fluid from horses with infectious synovitis. Synovial fluid samples from 6 horses with culture confirmed synovial infection were used for broad range 16S rRNA gene PCR. Synovial aspirates of 2 healthy horses were used as negative controls. Following extraction and purification of synovial fluid DNA, all samples were processed by touchdown PCR. Amplicons were detected by reverse line blot hybridisation and visualised with chemiluminescence. Pathogen-specific detection of 16S rRNA gene sequences was successful in all 6 synovial fluid samples. No bacterial DNA was detected in the aspirates from the negative control horses using touchdown PCR followed by 25 additional cycles of amplification. The identity of the pathogens was confirmed by DNA sequencing of the amplicons. It can be concluded that broad range 16S rRNA gene PCR followed by reverse line blot hybridisation is a promising technique for detection of bacterial DNA in synovial fluid samples. Further research should aim at the detection of bacterial DNA in synovial fluid samples suspected of infection but having negative culture results. When the 16S PCR proves to be reliable and more sensitive than standard culturing techniques, it may become a powerful tool in the diagnosis of synovial infection.  相似文献   
73.
The effect of dietary starch and fat content on serum creatine kinase (CK) activity and substrate availability was evaluated in 4 mares of Quarter Horse-related breeds with polysaccharide storage myopathy (PSSM). Four isocaloric diets ranging in digestible energy (DE) from 21.2% (diet A), 14.8% (B), 8.4% (C), to 3.9% (D) for starch, and 7.2% DE (diet A), 9.9% (B), to 12.7% DE (diet C and D) for fat were fed for 6-week periods (4 weeks with exercise) using a 4 X 4 Latin square design. Postprandial glucose and insulin responses were measured, and 4 hours postexercise, serum CK activity, glucose, insulin, free fatty acids (FFA), and beta-hydroxybutyrate (beta-HBA) were analyzed. Glycogen, glucose-6-phosphate, citrate synthase, 3-hydroxy-acyl-CoA dehydrogenase, lactate dehydrogenase as well as abnormal polysaccharide and lipid content were measured in middle gluteal muscle samples. Postprandial insulin and glucose response was higher for diet A versus D. Log CK activity was higher with diets A, B, and C versus D. Daily insulin was higher and FFA lower on diet A versus B, C, and D, whereas glucose varied only slightly with diet. Muscle oxidative capacity and lipid stores were low in PSSM horses and muscle glycogen and abnormal polysaccharide content high on both diets A and D. Individual variation occurred in the response of PSSM horses to diets differing in starch and fat content. However, for those horses with clinical manifestations of PSSM, a diet with <5% DE starch and >12% DE fat can reduce exertional rhabdomyolysis, potentially by increasing availability of FFA for muscle metabolism.  相似文献   
74.
The aim of this study was to evaluate single and double centrifugation tube methods for concentrating equine platelets. Whole blood samples were collected from clinically normal horses and processed by use of single and double centrifugation tube methods to obtain four platelet concentrates (PCs): PC-A, PC-B, PC-C, and PC-D, which were analyzed using a flow cytometry hematology system for hemogram and additional platelet parameters (mean platelet volume, platelet distribution width, mean platelet component concentration, mean platelet component distribution width). Concentrations of transforming growth factor beta 1 (TGF-beta(1)) were determined in all the samples. Platelet concentrations for PC-A, PC-B, PC-C, and PC-D were 45%, 44%, 71%, and 21% higher, respectively, compared to the same values for citrated whole blood samples. TGF-beta(1) concentrations for PC-A, PC-B, PC-C, and PC-D were 38%, 44%, 44%, and 37% higher, respectively, compared to citrated whole blood sample values. In conclusion, the single and double centrifugation tube methods are reliable methods for concentrating equine platelets and for obtaining potentially therapeutic TGF-beta(1) levels.  相似文献   
75.
The aim of the study was to determine the intraarticular serum amyloid A (SAA) response pattern in horses with inflammatory arthritis. Inflammatory arthritis was induced by injection of lipopolysaccharide (LPS) into the radiocarpal joint of four horses. Serum and synovial fluid (SF) samples were collected before and at 4, 8, 12, 24, 48, 72, 96, and 144 h after injection. Concentrations of SAA were measured by immunoturbidometry, and expression of SAA isoforms was visualized by denaturing isoelectric focusing and Western blotting. The LPS injection caused systemic and local clinical signs of inflammation. Serum amyloid A appeared in serum and SF within 8 h after LPS injection. Isoelectric focusing showed three major SAA bands with apparent isoelectric points (pI) of 7.9, 8.6, and >9.3 in serum and SF. Synovial fluid contained two additional isoforms with highly alkaline apparent pI values (apparent pI value extrapolated from standard curve = 10.0 and 10.2), which were not present in any of the serum samples. In conclusion, intraarticular injection of LPS induced systemic and local inflammatory responses in the horses. By demonstrating SF-specific SAA isoforms the results of the present study suggest that SAA is synthesized locally in the equine inflamed joint, similar to what has been demonstrated in humans previously. The marked local SAA synthesis suggests an important pathophysiological role in inflammatory arthritis.  相似文献   
76.
Mast cells normally are present in equine bronchoalveolar lavage fluid (BALF), but usually represent <2% of all cells in healthy horses. An increased percentage of mast cells has been associated with airway hyperactivity and inflammatory airway diseases, but marked differences are reported between studies in normal and diseased horses. Because an abnormal mast cell count may be of clinical relevance, we compared the ability of a fast Romanowsky method to stain mast cell granules with that of 3 metachromatic stains: automated Romanowsky, May-Grünwald Giemsa, and toluidine blue stains. The BALF cells from 24 horses were studied. A differential cell count was performed blindly on 400 cells. The percentages of mast cells obtained were analyzed by means of repeated-measures analysis of variance and Fischer's PLSD test. The Bland and Altman method was used to assess agreement among stains. The mean percentage of mast cells in BALF was significantly lower with the fast Romanowsky than with the automated Romanowsky, May-Grünwald Giemsa, and toluidine blue stains. With the fast Romanowsky stain, the metachromatic granules of mast cells were not stained, and their identification was based on morphologic criteria. Toluidine blue staining allowed detection of the highest mean percentage of mast cells, but was inadequate for performing a differential cell count on other cell types. In conclusion, fast Romanosky stain may be inadequate for detection of mast cells in equine BALF, whereas automated Romanowsky, May-Grünwald Giemsa, and toluidine blue stains provide metachromatic staining of mast cell granules.  相似文献   
77.
BACKGROUND: Small volume resuscitation has been advocated as a beneficial therapy for endotoxemia in horses but this therapy has not been investigated in a prospective manner. The objective of this study was to determine the cardiopulmonary effects of small-volume resuscitation using hypertonic saline solution (HSS) plus Hetastarch (HES) during experimental endotoxemia in anesthetized horses. HYPOTHESIS: Treatment of horses with induced endotoxemia using HES-HSS does not alter the response of various cardiopulmonary indices when compared to treatment with either small- or large-volume isotonic crystalloid solutions. ANIMALS: Eighteen healthy horses were randomly assigned to 1 of 3 groups. Anesthesia was maintained with halothane. Endotoxemia was induced by administering 50 microg/kg of Escherichia coli endotoxin IV. The horses were treated over 30 minutes with 15 mL/kg of balanced polyionic crystalloid solution (control), 60 mL/kg of balanced polyionic crystalloid solution (ISO), or 5 mL/kg of HSS followed by 10 mL/kg of HES (HSS-HES). METHODS: Prospective randomized trial. RESULTS: Cardiac output (CO) after endotoxin infusion increased significantly (P < .05) from baseline in all groups, whereas mean central venous pressure increased significantly (P < .05) in the ISO group only. Mean pulmonary artery pressure increased from baseline (P < .05) in horses treated with isotonic fluids and HSS-HES. There was no effect of treatment with HSS-HES on CO, systemic vascular resistance (SVR), mean arterial pressure, blood lactate concentrations, or arterial oxygenation. CONCLUSIONS AND CLINICAL IMPORTANCE: The use of HSS-HES failed to ameliorate the deleterious hemodynamic responses associated with endotoxemia in horses. The clinical value of this treatment in horses with endotoxemia remains unconfirmed.  相似文献   
78.
During the past two decades anthelmintic resistance in equine parasites has been found in the group of small strongyle species (cyathostomins) and in the ascarid species Parascaris equorum. The ubiquitous nature and possible severe consequences of disease with these nematodes make them the prime targets of current worm control programmes. Traditional control strategies mainly rely on the strategic application of anthelmintics, currently represented by three major drug classes: benzimidazoles (BZ), the tetrahydropyrimidine pyrantel (PYR) and macrocyclic lactones (ML). Following decades of routine and frequent anthelmintic applications, many cyathostomin populations on horse farms in industrialised countries must be considered as resistant to BZ anthelmintics. However, to date no published cases of cyathostomin disease specifically associated with anthelmintic resistance were reported. Possibly this is due to the generally subclinical and unspecific symptoms associated with cyathostomin infections. Nevertheless, exclusive reliance on the ML drug class may increase the threat of clinical disease due to drug-resistant cyathostomins. More recently, P. equorum has been reported as having developed resistance against ivermectin and moxidectin, two representatives of the ML-class. These anthelmintics are currently the most frequently used drug class in horses. This nematode species is mainly found in foals and in younger horses due to the development of immunity following exposure to infection. Infection with P. equorum can result in clinically drastic consequences such as obstruction and/or penetration of the small intestine, the latter usually leading to death. In conclusion, on horse farms the efficacy of anthelmintic treatments should be examined routinely for each drug class. Several factors can influence the rate at which anthelmintic resistance develops; high frequency of treatment being one of the most important. Modern control strategies should therefore attempt to significantly reduce anthelmintic treatments. Several pasture and farm management practices found to be negatively associated with nematode and anthelmintic resistance prevalence will be discussed in the review presented here.  相似文献   
79.
80.
Here, we present the results of a genetic analysis of 463 Pottoka ponies corresponding to four generations, using 17 microsatellite markers. Ten years after the beginning of the Pottoka conservation programme, the values for the genetic diversity of the breed are still high and stable, indicating the success of the programme. We found null alleles in Pottoka for the ASB23, HMS3 and HTG10 microsatellites. Together with information obtained from other pony breeds from the Iberian Peninsula, this finding indicates that these microsatellites should not be used for phylogenetic analyses or parentage tests, at least for these breeds. The high heterozygosity exhibited by this breed in comparison to other ponies, together with its genetic proximity to the centroid of the allele frequencies, suggest that Pottoka allele frequencies are close to those initially exhibited by the ancestors of current European ponies. The results obtained in the current work, together with results from previous studies of ponies and horses from the Iberian Peninsula, corroborate the idea of a unique origin of all ponies from the European Atlantic Area. In contrast, our results do not corroborate the idea that these are derived from a domestication event in the Iberian Peninsula, nor that they have incorporated ancient Iberian horse genes into their genetic pool to a larger extent than other horse breeds.  相似文献   
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