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81.
A total of 174 dogs from an area hyperenzootic for Dirofilaria immitis were grouped into 4 age categories and necropsied; information was obtained on adult D immitis infections and on the presence of microfilariae. Serum samples from these dogs were examined by an enzyme-linked immunosorbent assay (ELISA) for antibody to adult D immitis and by an indirect fluorescent antibody test (IFAT) for antibody to microfilarial surface antigens. In dogs less than or equal to 5 months of age, necropsy demonstrated no evidence of infection; however, positive serologic results indicated that some of these dogs had prepatent infections. The percentage of dogs with ELISA titers (positive) increased with age, as did the percentage of dogs with adult D immitis infections. The IFAT results were positive in some dogs in each age category. Sera from all 29 dogs with occult infections were positive by ELISA. Sera from 6 of 20 dogs with occult dual-sex heartworm infections and 1 of 9 dogs with occult single-sex heartworm infections were positive by IFAT. For diagnosing occult dirofilariasis, the ELISA had a positive predictive value which increased with age of the dog to a maximum of 65.0% in dogs greater than or equal to 12 months of age; ELISA had a negative predictive value of 100% in all age groups. In contrast, positive and negative predictive values for the IFAT decreased with age of the dog to 60% and 37.5%, respectively, in dogs greater than or equal to 12 months of age.  相似文献   
82.
The introduction of modern heartworm, flea, and tick preventatives has provided a safe and effective means of controlling companion animal endoparasites, but achieving good owner compliance remains an ongoing challenge for the veterinary profession. Based on a sample of patients from the veterinary teaching hospital at the University of Pennsylvania, this study retrospectively examined factors associated with preventative use and areas of potential weakness in client communication. Between 1999 and 2006, records of 5276 canine and 1226 feline patients were searched for signalment, survey results for heartworm, flea, and tick preventative use, date of visit, presenting complaint, vaccination history, and owner zip code. Data were analyzed using bivariate and multivariate techniques. Overall, only 13–23% of patients were questioned about heartworm, flea, or tick preventative use during routine medical history taking. Patients with a prior history of parasites, younger patients, or those presenting with signs of cardiac disease were no more likely to be questioned about preventative use than healthy animals. Patients presenting to a specialty service were also less likely to be questioned. Approximately 74–79% of dogs and 12–38% of cats in the sample were on preventative products at any given time. There was a distinct seasonality to preventative use corresponding to the heartworm transmission season from June through November in the northeastern United States. Only 50% of patients seen for a yearly physical examination in winter were reported to be using preventative products when surveyed later in the year, compared to the roughly 85% on patients in heartworm preventatives when they received their routine physical examination in spring. Month of presentation and neuter status were the only signalment factors significantly (P < 0.05) associated with preventative use in the multivariate analysis. Findings from this study emphasize target areas for increasing owner compliance.  相似文献   
83.
A newly-formulated, high protein high fibre (HPHF) diet has recently been shown to improve satiety in dogs. The current study examined its performance during weight loss in client-owned dogs with naturally-occurring obesity. Fifteen dogs were fed the HPHF diet, whilst a matched ‘control’ group of 27 dogs, received a high protein medium fibre diet (HPMF), with an equivalent caloric density. Baseline characteristics (signalment, percentage overweight, and body fat percentage) were not significantly different between groups. However, percentage weight loss was greater (median [range] 31.8% [12.0–41.2%] vs. 20.0% [5.9–45.0%], P = 0.016) and mean rate of weight loss faster (median [range] 1.0%/week [0.3–1.6%] vs. 0.7%/week [0.3–1.5%], P = 0.028) on HPHF compared with HPMF. Percentage body fat mass decrease (measured by dual-energy X-ray absorptiometry) was also greater in dogs fed the HPHF diet (median (range] 58% [32–85%) vs. 37% [15–72%), P = 0.002). Thus, a diet formulated to include high levels of both protein and fibre, improves outcome during weight loss in obese dogs.  相似文献   
84.
OBJECTIVE: o determine sensitivity and specificity of radiography, ultrasonography, and antegrade pyelography for detection of ureteral obstructions in cats. DESIGN: Retrospective study. ANIMALS: 11 cats. PROCEDURE: Medical records of cats that had radiography, ultrasonography, and antegrade pyelography performed for suspected ureteral obstructions were examined. Ultrasound-guided pyelocentesis and fluoroscopic-assisted antegrade pyelography were performed on 18 kidneys in 11 cats. Obstructive ureteral lesions were confirmed in all cats by surgical or necropsy examination. Sensitivity and specificity of survey radiography, ultrasonography, and antegrade pyelography for identification of ureteral obstructions were calculated. Surgical or necropsy findings were used as the standard for comparison. RESULTS: All cats were azotemic. Mean +/- SD serum creatinine and BUN concentrations were 10.2 +/- 6.1 and 149 +/- 82 mg/dL, respectively. Fifteen of 18 ureters were found to be obstructed at surgery or necropsy. Sensitivity and specificity were 60 and 100% for radiography and 100 and 33% for ultrasonography, respectively, in identification of ureteral obstructions. Leakage of contrast material developed in 8 of 18 kidneys during antegrade pyelography and prevented diagnostic interpretation in 5 of 18 studies. For the 13 diagnostic studies, specificity and sensitivity were 100% by use of the antegrade pyelography technique. Correct identification of the anatomic location of the ureteral obstruction was obtained in 100% of diagnostic antegrade pyelography studies and in 60% of radiography or ultrasonography studies. CONCLUSIONS AND CLINICAL RELEVANCE: Antegrade pyelography can be a useful alternative in the diagnosis and localization of ureteral obstructions in azotemic cats, although leakage of contrast material may prevent interpretation of the study.  相似文献   
85.
Urethral obstruction is a life‐threatening form of feline lower urinary tract disease. Ultrasonographic risk factors for reobstruction have not been previously reported. Purposes of this retrospective cross‐sectional study were to describe urinary tract ultrasound findings in cats following acute urethral obstruction and determine whether ultrasound findings were associated with reobstruction. Inclusion criteria were a physical examination and history consistent with urethral obstruction, an abdominal ultrasound including a full evaluation of the urinary system within 24 h of hospitalization, and no cystocentesis prior to ultrasound examination. Medical records for included cats were reviewed and presence of azotemia, hyperkalemia, positive urine culture, and duration of hospitalization were recorded. For medically treated cats with available outcome data, presence of reobstruction was also recorded. Ultrasound images were reviewed and urinary tract characteristics were recorded. A total of 87 cats met inclusion criteria. Common ultrasound findings for the bladder included echogenic urine sediment, bladder wall thickening, pericystic effusion, hyperechoic pericystic fat, and increased urinary echoes; and for the kidneys/ureters included pyelectasia, renomegaly, perirenal effusion, hyperechoic perirenal fat, and ureteral dilation. Six‐month postdischarge outcomes were available for 61 medically treated cats and 21 of these cats had reobstruction. No findings were associated with an increased risk of reobstruction. Ultrasonographic perirenal effusion was associated with severe hyperkalemia (P = 0.009, relative risk 5.75, 95% confidence interval [1.54–21.51]). Findings supported the use of ultrasound as an adjunct for treatment planning in cats presented with urethral obstruction but not as a method for predicting risk of reobstruction.  相似文献   
86.
87.
Rift Valley fever virus (Phlebovirus, Bunyaviridae) is an arbovirus causing intermittent epizootics and sporadic epidemics primarily in East Africa. Infection causes severe and often fatal illness in young sheep, goats and cattle. Domestic animals and humans can be contaminated by close contact with infectious tissues or through mosquito infectious bites. Rift Valley fever virus was historically restricted to sub-Saharan countries. The probability of Rift Valley fever emerging in virgin areas is likely to be increasing. Its geographical range has extended over the past years. As a recent example, autochthonous cases of Rift Valley fever were recorded in 2007–2008 in Mayotte in the Indian Ocean. It has been proposed that a single infected animal that enters a naive country is sufficient to initiate a major outbreak before Rift Valley fever virus would ever be detected. Unless vaccines are available and widely used to limit its expansion, Rift Valley fever will continue to be a critical issue for human and animal health in the region of the Indian Ocean.  相似文献   
88.
The comparison of resistance to natural tick infestation by Rhipicephalus microplus (Canestrini, 1887) of crossbred Senepol?×?Limousin and purebred Limousin cattle was investigated. The Senepol breed, originated from St Croix Island in the Caribbean is considered as a Bos taurus breed adapted to tropical conditions. Despite its B. taurus genetic background, it is believed to have a good tick resistance, but this resistance has never been assessed previously. Tick counts under natural infestation were carried out to investigate the difference of susceptibility between crossbred Senepol?×?Limousin and purebred Limousin cattle. Mixed-effect models were used to assess the effect of the breed on the number of ticks. Results show that Senepol?×?Limousin are five times less infested by ticks than purebred Limousin. These results underline the opportunity to use Senepol cattle for crossing with susceptible B. taurus breeds in tick infested areas, to combine tick resistance with beef production abilities.  相似文献   
89.
A study was conducted on 37 randomly selected broiler poultry farmers in Rwanda to characterize the production system using pre-tested semi-structured questionnaires. The data were processed in SPSS and presented as means, percentages and ranges in tables and text. All respondents kept Cobb breed and young stock was mainly (73 %) imported from abroad. The majority of respondents were males (68 %) and most farmers had attended only primary level of education (40.5 %). Most of the farms were in the peri-urban (48.6 %) and urban (37.8 %) areas and hired male youth (62.2 %) mainly aged 19–35 years. The majority of respondents (68 %) kept less than 500 birds per batch. Recordkeeping was well practiced (91.9 %) and (62.6 %) had permanent poultry houses and all farmers used deep litter system. Purchased feedstuffs were reportedly (92 %) mixed at farm level as the main feed resource. Maize bran was reported (97.06 %) the main, basal feedstuff. The mortality rates of chick and growers were 12.3 and 9.4 %, respectively. The slaughter age was reportedly 60 days with an average dressing percentage of 75.67 %. The main challenges reported were scarcity and unaffordability of quality feeds (59.5 %), lack of market access (45 %) and lack of credit (21 %). The farmers had various views on improving broiler production in Rwanda ranging from establishing feed processing industries 62.2 %, improving marketing facilities 35.1 %, increasing availability of day-old chick and access credit 27 %, to intensification of farmer training 16.2 %.  相似文献   
90.
Pasteurella multocida was isolated from the lungs of calves that died on a farm in the south of England. This organism was inoculated experimentally into 13 calves by the intratracheal route: in all but two of the calves mild clinical disease resulted and at necropsy, three or four days later, pneumonic consolidation involving up to 22 per cent of the lung was observed. P multocida was isolated from all but two of the lungs. Of two calves inoculated intravenously with P multocida, one showed mild clinical disease and slight pneumonic consolidation at necropsy and the other remained normal. Control calves inoculated intratracheally and intravenously with sterile broth showed no signs of illness and no pneumonic consolidation. Histologically the lung lesions comprised a fibrinous bronchopneumonia with variable sized areas of coagulative necrosis, extensive deposition of fibrin and massive dilatation and oedema of the interlobular and pleural lymphatics. It is concluded that P multocida should receive more recognition as a primary pathogen.  相似文献   
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