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31.
Objective   To evaluate the effect of a non-occlusive dressing incorporated in a 3-layer bandage on second intention healing of wounds of the distal portion of the limb.
Study Design   Untreated wounds in 33 adult horses used in four studies using the same wound-healing model conducted over 5 years.
Methods   Standardised, full-thickness wounds were made in the skin overlying the dorsomedial aspect of the mid-metacarpus; 17 horses were bandaged with a non-occlusive dressing covered by gauze-coated cotton wool that was compressed with adhesive tape; 16 horses were left unbandaged. Wounds were photographed weekly for 9 weeks and the images were analysed electronically.
Results   There were significant effects associated with bandage (P < 0.0001), week (P < 0.001), and bandage by week interaction (P < 0.0001). There was no difference in wound area at the first time-point after wound creation (P = 0.38). After week 1, there was a difference between bandaged and unbandaged wounds in wound area at each measurement until the end of the study. Bandaged wounds showed greater and more prolonged retraction. Unbandaged wounds retracted for 2 weeks before beginning to contract, whereas bandaged wounds continued to retract for 3 weeks. In bandaged wounds excess granulation tissue required regular trimming, but not in unbandaged wounds. There was no difference between groups in the total days to healing or the overall rate of healing.
Conclusions   These results should be treated with caution until validated with contemporaneous, controlled studies. Covering a wound with a non-occlusive dressing in a 3-layer bandage led to greater wound retraction, modulated the rate of wound contraction and promoted excessive granulation tissue. If excessive granulation tissue is excised regularly, bandaging has no effect on total time to healing.  相似文献   
32.
A study of randomly selected dairy farms in England and Wales was made between October 1999 and February 2001 to estimate the prevalence and incidence of Salmonella serovars. The farms were enrolled through five milk-buying companies, which represented 63 per cent of the dairy farms in England and Wales, and they were sampled on up to four occasions (449 farms at visit 1, 272 farms at visit 2, 251 farms at visit 3 and 243 farms at visit 4). In total, 19,296 samples of pooled faecal pats and slurry were collected. The farm-specific prevalence of all serovars of Salmonella ranged from 12.1 per cent (95 per cent confidence interval [CI] 8.2 to 16.0 per cent) to 24.7 per cent (95 per cent CI 19.4 to 30.1 per cent) at each visit. The most common serovars identified were Salmonella Dublin (3.7 to 6.6 per cent farm-specific prevalence at each visit), Salmonella Agama (1.8 to 7.6 per cent) and Salmonella Typhimurium (2.6 to 4.1 per cent) The prevalence varied by region and month of sampling and increased in late summer. The incidence rate of all serovars of Salmonella was 0.43 (95 per cent CI 0.34 to 0.54) cases per farm-year at risk. There was no significant difference between the incidence rates of the common serovars S Typhimurium (0.07), S Dublin (0.06) and S Agama (0.13). A total of 29 Salmonella serovars were isolated. Few of the isolates were resistant to the 16 antimicrobial agents tested, except the isolates of S Typhimurium dt104, of which 67.9 per cent were resistant to at least five of them.  相似文献   
33.
REASONS FOR PERFORMING STUDY: Previous studies of sinus surgery on standing horses have been based on techniques which utilise powered hand bone saws and preserve the bone flap, which was thought to be essential for a good cosmetic result. This report describes a simplified technique applied to the standing horse where the sinus flap construction used a large skull trephine and where the bone flap is necessarily discarded. OBJECTIVES: To assess whether the modified standing frontonasal flap (SFF) surgery offers an effective method to investigate and/or treat sinunasal disorders in the horse. METHODS: The case records of 60 horses subjected to modified SFF surgery were reviewed to analyse the efficacy of the technique when applied to a range of sinunasal disorders in terms of diagnosis, surgical findings, complications and long-term outcomes, including cosmetic effect. RESULTS: Resolution of clinical signs was achieved in 54 out of 60 horses, and for the remainder the SFF technique proved useful on a diagnostic basis. The cosmetic result was, in the opinion of the owners, excellent or satisfactory in 48 of 56 (86%) horses. CONCLUSIONS: The modified SFF technique was found to be practicable and provided satisfactory exposure of the sinus contents for diagnosis and removal of diseased tissue in a range of disorders. An acceptable cosmetic result can be obtained in the majority of horses despite rejection of the disc of overlying bone. Apart from avoiding the risks associated with general anaesthesia, the advantages of the modified SFF sugery are: a reduction of haemorrhage in the standing horse; reduced mucosal engorgement; straightforward anatomical orientation; a comfortable working height; and reduced surgery time. A sound knowledge of the functional anatomy of the area is a prerequisite before embarking on any form of sinunasal surgery. Complications are infrequent and usually transient. POTENTIAL RELEVANCE: The modified SFF technique is a valuable alternative to other invasive methods of sinunasal surgery.  相似文献   
34.
Three experiments utilizing broilers were conducted in different environments to evaluate the effects of Innavax (INX; spray-dried serum) administered in drinking water on broiler performance. In Exp. 1 (1 to 42 d), 252 Ross x Cobb male broilers were assigned randomly to one of six treatments consisting of tap water mixed with 0, 0.25, 0.50, 0.75, 1.0, or 1.25% (wt/wt) INX. Broilers (six broilers per pen; seven pens per treatment) were housed in Petersime battery cages (raised wire flooring) in temperature-controlled rooms. Average daily gain, and feed and water intake (as-fed) were not affected (P > 0.05) by experimental treatments. Feed efficiency tended to improve linearly (P = 0.076) from d 0 to 7 with increasing levels of INX, but was unaffected (P > 0.05) during the remaining periods. In Exp. 2 and 3, 800 Ross x Ross 308 male broilers (400 broilers in each trial; 10 broilers per pen; 10 pens per treatment) in two 21-d experiments were assigned randomly to one of four treatments consisting of tap water mixed with 0, 0.45, 0.90, or 1.35% (wt/wt) INX. Broilers were housed in floor pens containing clean (Exp. 2) or used (Exp. 3) litter. In Exp. 2, intake, ADG, and feed efficiency were linearly improved (P < 0.05) during the first week with increasing levels of INX. During the second week (d 8 to 14), ADG, water intake, and feed efficiency were linearly improved (P < 0.05) with increasing levels of INX. In the third week (d 15 to 21), ADG and feed and water intake were not affected (P > 0.10) by level of INX. Overall (d 0 to 21), ADG, intake, and feed efficiency were linearly improved (P < 0.05) with INX. In Exp. 3, ADG, water intake, and feed efficiency were linearly improved (P < 0.05) during each period. Feed intake was not affected (P > 0.05) by experimental treatment during d 0 to 7, but was linearly increased (P < 0.05) from d 8 to 14 and 15 to 21. The greatest growth response of broilers to INX was observed when broilers were housed in floor pens with used litter, followed by floor pens with clean litter and battery pens. Further research on the relationship between the response to INX and housing conditions seems warranted.  相似文献   
35.
The medical records of 80 horses treated for left laryngeal hemiplegia by prosthetic laryngoplasty, ventriculectomy and vocal cordectomy were examined, first to compare the subjective and objective success rates for groups of horses of different ages and used for different purposes, and secondly, to compare the efficacy of including vocal cordectomy in the surgical protocol with published success rates for laryngoplasty and ventriculectomy alone. Subjectively, 70 per cent of the horses were said to have had a successful surgical outcome. The success rate for thoroughbred racehorses (66 per cent) was lower than for other breeds (90 per cent) on the basis of a subjective assessment by owners and trainers. Thoroughbreds two years old or younger had a success rate of 69 per cent, but older thoroughbreds had a success rate of 61 per cent. Of the 17 horses for which an objective performance index could be calculated, 10 (59 per cent) had an improved performance postoperatively. There was a nearly significant association between the objective and subjective assessments (P=0.078). Six of 69 horses (8.7 per cent) continued to make a respiratory noise after surgery. The subjective assessment of success did not appear to correlate with the objective measure of success used in this study and age had no apparent association with a successful surgical outcome. Inclusion of a vocal cordectomy in the surgical protocol may be more important in the eradication of postoperative respiratory noise than in improving clinical success rates.  相似文献   
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Medical records of 72 dogs diagnosed with immune-mediated hemolytic anemia (IMHA) were reviewed to find risk factors for the disease, for mortality, and for thromboembolism. Coagulation data of 32 patients were evaluated for mortality or thromboembolism risk factors. Cocker Spaniels were at increased risk for IMHA (P = .012). Timing of vaccination was not associated with development of IMHA. PCV ranged from 5 to 33%, with a mean of 16 +/- 5%. Autoagglutination was present in 42% of the dogs. Platelet counts (n = 60) varied from 3,000 to 793,000/microL (mean, 160,117 +/- 133,571; median, 144,000). Thrombocytopenia (platelet count, <200,000/microL) was present in 70% of the dogs, with severe thrombocytopenia (platelet count, <50,000/microL) being present in 22%. One-step prothrombin time (OSPT) was prolonged in 28% of the dogs tested, and activated partial thromboplastin time (APTT) was prolonged in 47% of the dogs tested. Fibrin(ogen) degradation products (FDPs) were detected in 16 of 28 dogs tested (57%). Disseminated intravascular coagulation (DIC) was diagnosed in 10 of 31 (32%) dogs and was suspected in 8 dogs. Thromboemboli were found in 20 of 25 dogs given postmortem examinations. Mortality rate was 58%. Thrombocytopenia (P = .008) and serum bilirubin concentration of >5 mg/dL (P = .015) were risk factors for mortality, and hypoalbuminemia approached significance (P = .053). Severe thrombocytopenia (P = .046), serum bilirubin concentration of >5 mg/dL (P = .038), and hypoalbuminemia (P = .016) were risk factors for thromboembolism. On evaluation of continuous data, decreased platelet count (P = .057), increased bilirubin (P = .062), and decreased albumin (P = .054) approached significance for decreased survival. A higher risk for thrombosis was found with increased alkaline phosphatase (ALKP) (P = .042), increased bilirubin (P = .047), and decreased albumin (P = .012).  相似文献   
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Spotted Fever Group Rickettsia is important cause of emerging and re-emerging infectious disease in people and dogs. Importantly, dogs can serve as sentinels for disease in people. Sensitive and specific diagnostic tests that differentiate among species of infecting Rickettsia are needed. The objective of this study was to develop a sensitive and specific PCR that differentiates SFG Rickettsia infecting dog blood. Conventional and real-time PCR assays were developed using primers that targeted a small region of the ompA gene. Their sensitivity, determined by testing a cloned target sequence in the presence of host DNA, was 15–30 and 5 copies of DNA, respectively. Testing of Rickettsia cultures and analysis of Rickettsia gene sequences deposited in GenBank verified DNA could be amplified and used to differentiate species. DNA from the blood of infected dogs was also tested. Importantly, Rickettsia DNA was detected before seroconversion in some dogs. The species of infecting Rickettsia was also identified. We conclude these assays may assist in the timely diagnosis of infection with SFG Rickettsia. They may also facilitate the discovery of novel SFG Rickettsia infecting dogs, and in the investigation of dogs as sentinels for emerging rickettsioses.  相似文献   
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