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51.
Barthel R Piedrahita JA McMurray DN Payeur J Baca D Suárez Güemes F Perumaalla VS Ficht TA Templeton JW Adams LG 《American journal of veterinary research》2000,61(9):1140-1144
OBJECTIVE: To determine necropsy and Mycobacterium bovis culture results in cattle from herds with tuberculosis, the role of the bovine NRAMP1 gene in resistance and susceptibility to infection with M bovis, and the association between magnitude of the tuberculous lesions and various types of M bovis isolates. ANIMALS: 61 cattle from herds with tuberculosis in Texas and Mexico. PROCEDURE: 61 cattle were evaluated by necropsy; 59 had positive and 2 had negative caudal fold tuberculin intradermal test (CFT) results. Thirty-three cattle with positive CFT results were genotyped to evaluate polymorphism of the 3' untranslated region of the bovine NRAMP1 gene, using single-stranded conformational analysis, 9 were resistant to M bovis with no tuberculous lesions and negative M bovis culture results, and 24 were susceptible with tuberculous lesions and positive M bovis culture results. Isolates of M bovis were analyzed by restriction fragment length polymorphism (RFLP) on the basis of IS6110 sequences and direct-repeat fingerprinting patterns. RESULTS: 21 (35.6%; 21/59) cattle with positive CFT results had tuberculous lesions or positive culture results; in addition, 1 of 2 cattle with negative CFT results had tuberculous lesions and positive culture results. Tuberculous lesions were most common in the thorax (35/63; 55.5%) and lymphoid tissues of the head (10/63; 15.9%). Tuberculous lesions varied from 1 to 11/animal; 8 of 21 (38.1%) had solitary lesions. Associations were not found between resistance or susceptibility to infection with M bovis and polymorphism in the NRAMP1 gene or between the magnitude of the lesions and various RFLP types of M bovis isolates. CONCLUSIONS AND CLINICAL RELEVANCE: The NRAMP1 gene does not determine resistance and susceptibility to infection with M bovis in cattle. 相似文献
52.
Murphey ED Schneider RK Adams SB Santschi EM Stick JA Ruggles AJ 《Journal of the American Veterinary Medical Association》2000,216(12):1949-1954
OBJECTIVE: To determine clinical features of horses with a slab fracture of the central or third tarsal bone and to report outcome of horses in which treatment did not include surgery. DESIGN: Retrospective study. ANIMALS: 25 horses (14 Standardbreds, 6 Thoroughbreds, 5 Quarter Horses). PROCEDURE: Medical records of horses with a slab fracture of the central (n = 9) or third (16) tarsal bone were reviewed. Only horses for which treatment consisted of confinement to a stall were included in this study. Clinical features and radiographic findings were recorded and summarized. Outcome was determined for racing breeds by obtaining official lifetime race results. Outcome for Quarter Horses was determined by phone survey of the owners. RESULTS: 16 (64%) horses had a successful outcome. Ten of 14 (71%) Standardbreds and 2 of 6 Thoroughbreds returned to racing and started at least 5 races after injury. Four of 5 Quarter Horses for which follow-up information was available successfully returned to their previous activity. Sex, age, limb affected, or gait was not associated with final outcome. Percentage of racehorses with central tarsal bone fractures that had a successful outcome (2/7) was significantly less than percentage with third tarsal bone fractures that did (10/13). CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that enforced rest without surgical fixation can be an effective therapeutic option for horses with a slab fracture of the central or third tarsal bone, even if athletic function is expected. 相似文献
53.
Adams CL Bonnett BN Meek AH 《Journal of the American Veterinary Medical Association》2000,217(9):1303-1309
OBJECTIVE: To identify predictors of grief and client desires and needs as they relate to pet death. DESIGN: Cross-sectional mail survey. SAMPLE POPULATION: 177 clients, from 14 randomly selected veterinary practices, whose cat or dog died between 6 and 43 days prior to returning the completed questionnaire. PROCEDURE: Veterinary practices were contacted weekly to obtain the names of clients whose pets had died until approximately 200 clients were identified. Clients were contacted by telephone, and a questionnaire designed to measure grief associated with pet death was mailed to those willing to participate within 1 to 14 days of their pet's death. The questionnaire measured potential correlates and modifiers of grief and included three outcome measures: social/emotional and physical consequences, thought processes, and despair. Demographic data were also collected. RESULTS: Approximately 30% of participants experienced severe grief. The most prominent risk factors for grief included level of attachment, euthanasia, societal attitudes toward pet death, and professional support from the veterinary team. CONCLUSIONS AND CLINICAL RELEVANCE: Bivariate and multivariate analyses highlighted the impact owners' attitudes about euthanasia and professional intervention by the veterinary team had on reactions to pet death. Owners' perceptions of societal attitudes, also a predictor of grief, indicate that grief for pets is different than grief associated with other losses. 相似文献
54.
Gonadal function, sexual behavior, feedlot performance, and carcass traits of ram lambs actively immunized against GnRH 总被引:1,自引:0,他引:1
Kiyma Z Adams TE Hess BW Riley ML Murdoch WJ Moss GE 《Journal of animal science》2000,78(9):2237-2243
The effect of active immunization against GnRH on production, carcass, and behavioral traits was examined in ram lambs fed to a uniform slaughter weight. Lambs (initial BW = 32.6+/-1 kg) were stratified by BW and assigned at random to one of four treatment groups (n = 12 lambs/group). Lambs were untreated, castrated, or actively immunized against GnRH using a GnRH-keyhole limpet hemocyanin conjugate (1 mg) emulsified with either Freund's complete adjuvant (FCA) or another oil-based adjuvant (ISA). Animals were housed individually and slaughtered at 58 kg BW. Immunoneutralization of GnRH reduced (P < .05) testes weight and the concentration of testosterone in serum at slaughter. Suppression of testicular size and function was most clearly evident in animals immunized using FCA. Final anti-GnRH titer was also highest in lambs immunized using FCA. Several measures of sexual behavior (frequency of mounts and ejaculations) were also reduced (P < .05) in animals immunized using FCA. The duration of the feeding period was greater (P < .05) for castrated lambs than for untreated lambs, and intermediate feeding periods were required for FCA and ISA lambs. Average daily gain was greater (P < .05) in untreated than in castrated, FCA, or ISA lambs. Similarly, feed efficiency for untreated lambs was greater (P < .05) than for castrated, FCA, or ISA lambs, but feed efficiency did not differ among castrated, FCA, or ISA lambs. Longissimus muscle area, lean and bone maturity, overall quality, muscling score, flank streaking, and color of fat did not differ among treatments. Intact, FCA, and ISA lambs had more (P < .05) desirable yield grades, less (P < .05) backfat, and less (P < .05) marbling than castrated lambs. In summary, immunization against GnRH decreased testicular weight and reduced (P < .05) feedlot performance and sexual behavior to levels comparable to those of castrated males. Partitioning of nutrients for growth and deposition of fat, however, seems to differ among immunologically castrated and physically castrated lambs. This difference in nutrient partitioning may be due to residual testicular activity in immunized lambs. 相似文献
55.
56.
Prevalence and genotypic characterisation of Giardia in dairy calves from Western Australia and Western Canada 总被引:1,自引:0,他引:1
In this study, the prevalence of Giardia duodenalis infections was determined in Western Canadian and Western Australian dairy calves. Faecal samples were collected from Holstein calves located on a commercial dairy near Lethbridge, Alta., Canada (N=28) and from calves located on two commercial dairies located near Perth, WA, Australia (N=36). Faecal samples were examined for the presence of Giardia cysts using sucrose gradient centrifugation, followed by immunofluoresence microscopy. DNA was then extracted from Giardia isolates obtained from positive samples. A PCR based method was employed to amplify and sequence a 292bp region of the 16S-rRNA gene. Genetic sequences obtained from Giardia isolates were compared to each other and to previously sequenced isolates. Following a single faecal sample, 58% of Western Australian calves and 57% of Western Canadian calves were positive for Giardia. Geometric mean cyst counts/g of faeces were 839 for Western Australian calves and 3475 for Western Canadian calves, but these values did not differ significantly. Genetic sequences were obtained from 10 calves from Western Canada, while six sequences were obtained from Western Australian calves. Of the Western Canadian isolates, eight aligned with the proposed 'Hoofed livestock' genotype. Of the five isolates obtained from Western Australian calves, four sequences were identical to the 'Hoofed livestock' genotype. Two isolates from the Western Canadian calves and one isolate from the Western Australian calves had the identical genetic sequence to the Genotype (Assemblage) A sequence, a common human genotype. The results of this study demonstrate, for the first time, that Giardia infections occur in Western Australian calves. Also, calves from different geographical locations appear to be primarily infected with a Giardia genotype unique to hoofed livestock. However, calves can shed Giardia cysts potentially infective for humans. Thus, Giardia infections should be considered important to Australian dairy producers, and infections in calves may pose a risk to public health regardless of geographical location. 相似文献
57.
A. Hayes V. Adams K. Smith G. Maglennon S. Murphy 《Veterinary and comparative oncology》2007,5(3):168-176
The effect of treatment with vinblastine and prednisolone chemotherapy in dogs undergoing only surgical excision of Patnaik grade III cutaneous mast cell tumours is reported. Potential explanatory variables were explored using Kaplan–Meier survival analysis with log‐rank tests. During a median follow‐up period of 429 days, the overall median survival time (MST) was not reached (lower 95% CI = 322 days). The 1‐year survival probability was 0.71 (standard error 0.1), remaining unchanged at 2 years. Secondary disease at presentation was an independent risk factor for survival (P= 0.045). The MST of dogs presenting with secondary disease was 322 days, with a lower 95% confidence interval of 142 days and a 1‐year survival of probability of 0.47 (standard error 0.19). Adverse effects were recorded in 6 of the 108 (5.6%) vinblastine doses given. This chemotherapy regimen is a well‐tolerated adjunct to surgery for grade III mast cell tumours and appears to prolong survival compared with that expected with surgery alone. 相似文献
58.
Nicola Grint BVSc DVA DiplECVA MRCVS Dylan Gorvy BSc BVSc PhD CertES MRCVS Alexandra Dugdale MA VetMB DVA DiplECVA MRCVS 《Journal of Equine Veterinary Science》2007,27(5):221-227
A 13-year old Thoroughbred cross gelding (528 kg) underwent lameness investigation. Because of his temperament, general anesthesia was required to facilitate ultrasound of the left fore fetlock and intra-articular medication of three joints. Anesthesia was induced with ketamine/diazepam after acepromazine/detomidine premedication. Anesthesia was maintained for 40 minutes with a guaifenesin/detomidine/ketamine intravenous infusion. Recovery from anesthesia was initially uneventful, although of a moderate duration (70 minutes). Once standing, the horse proceeded to box walk in an agitated state and became recumbent on two occasions. The horse was manually restrained, at which time its rectal temperature was 41.8°C. Cooling measures were employed (fans, ice-water enemas, wet rugs, intravenous fluid therapy (IVFT), and topical application of surgical spirit) until rectal temperature reached 38.7°C. IVFT was continued for a further 16 hours. Four days after recovery from anesthesia, bilateral triceps, deltoideus, trapezius, and rhomboideus muscle swelling was observed. Blood creatinine kinase was elevated (24,898 IU/L). Treatment for postanesthetic myopathy was initiated (hot packing of the muscle groups, topical dimethylsulfoxide [DMSO] cream application, and oral phenylbutazone). Myoglobinuria was not observed at any time. Muscle swelling decreased over the following 3 days. The horse was discharged on day 11 and has since returned to work. 相似文献
59.
Otmar Spring Mark Bachofer Marco Thines Alexandra Riethmüller Markus Göker Franz Oberwinkler 《European journal of plant pathology / European Foundation for Plant Pathology》2006,114(3):309-315
Sequence parts of the internal transcribed spacer (ITS) region of nuclear ribosomal DNA were analysed to screen for the intraspecific
variability of a non-coding genomic region in 15 Plasmopara halstedii populations of different pathotype and geographic origin. Samples revealed uniformity in a ca. 790 Bp fragment comprising
of the ITS-1, 5.8S and front parts of the ITS-2. In contrast, clear differences were found in a ca. 810 Bp fragment of the
ITS-2 thus allowing differentiation between populations of pathotype 100, 310 and 330 and a group of populations representing
pathotypes 700, 701, 703, 710 and 730. Samples of pathotypes 700 to730 originated from Slovakia, France, and Germany, but
were uniform in both ITS sequence parts, thus indicating very recent origin of these highly aggressive physiological races.
The potential use of ITS sequences for pathotype differentiation and phylogenetic studies in P. halstedii is discussed. 相似文献
60.
Urban dwellers experience conflicting thoughts and feelings about urban woodlands; valued for their natural qualities, the relief they provide from the stress of modern urban living and the opportunities they afford for children's play and exploration. At the same time the seclusion inherent in this type of urban greenspace seems fraught with risk from crime, vandalism and abuse. Whilst many of these characteristics are well-researched, less is known about the differing perceptions of particular social groups. This study aimed to explore the ways in which age affects urban dwellers’ aspirations, values and fears concerning the woods, and woodland accessibility, focusing on the views of elderly people (aged over 65). This pilot study was based in Norfolk Heritage Park, an urban park containing a variety of woodland settings located in Sheffield, UK. The questionnaire survey (participantsn=97) revealed that although walking is the most popular leisure activity, most respondents did not visit urban parks as often as they would like, regardless of age. Whilst many of the meanings associated with urban woodland (“relaxation”, “peacefulness”, “seasonal change”, “scenery” and “education”) were shared amongst age groups, it seemed that the elderly respondents particularly valued the woods for their links with the past, and opportunities for immersion in the natural world. Some respondents from all age groups had fears about their personal security in the woodland, and the concerns of the elderly were heightened by their perceived frailty, reduced mobility and sense of vulnerability; this age group had a corresponding need for particular measures to alleviate these problems. The study provides preliminary evidence for the idea that adults of different ages have differing perceptions and requirements in relation to urban woodlands. Due to the small sample size and other methodological issues, further research is needed to confirm and develop the findings. 相似文献