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51.
Brucella suis is an emerging, zoonotic disease predominantly affecting dogs and humans that engage in feral pig hunting in Australia and other countries. Although B. suis infection in dogs shares some clinical similarities to the host-adapted species (B. canis), B. suis remains an incompletely understood pathogen in dogs with limited published data on its pathogenesis and clinical features. This case series describes the presentations, diagnosis, and clinical management of B. suis infection in three dogs: (1) a bitch with dystocia, abortion and mastitis; (2) an entire male dog with septic arthritis and presumptive osteomyelitis; and (3) a castrated male dog with lymphadenitis. Unique features of these cases are reported including the first documented detection of B. suis from milk and isolation from lymph nodes of canine patients, as well as the follow-up of pups born to a B. suis-infected bitch. Consistent with previous reports, all three dogs showed a favourable clinical response to combination antibiotic therapy with rifampicin and doxycycline. Individually tailored drug regimens were required based on the clinical presentation and other factors, including owner expectations and compliance with therapy as well as a zoonotic risk assessment (generally considered low, except around time of whelping). The authors include their recommendations for the clinical management of dogs that are at-risk or seropositive for B. suis with or without clinical signs or laboratory-confirmed infection.  相似文献   
52.
CF Chou  AJ Jin  SW Hui  CC Huang  JT Ho 《Science (New York, N.Y.)》1998,280(5368):1424-1426
An unexpected three-stage melting transition has been observed in two-dimensional (2D) free-standing liquid-crystal films by in situ electron-diffraction and optical-reflectivity measurements. These data suggest the existence of two phases between the 2D solid and liquid: a hexatic phase and, at a higher temperature, an intermediate liquid phase with hexatic-like positional correlations ( approximately 40 angstroms) but no long-range orientational order. Previous high-resolution heat-capacity measurements have revealed a divergent-like anomaly at the hexatic-liquid transition that sharply contradicts the predictions of 2D melting theories. The observation of an intermediate isotropic phase may alter our understanding of 2D melting and lead to reconciliation between current experiments and theories.  相似文献   
53.
A survey of the genetic diversity among the major cuban rice cultivars was conducted using isozyme, RAPD and AFLP markers. Polymorphisms were detected for esterases, peroxidases, alcohol dehydrogenases and polyphenoloxidases systems; 21 RAPD primers and four AFLP primer combinations. Heterozygosity arithmetic mean value (Hav(p)), the effective multiplex ratio (EMR) and the marker index (MI), were calculated for isozyme, RAPD and AFLP markers. The mean value of genetic similarity among the different varieties was 0.92 for isozyme, 0.73 for RAPD and 0.58 for AFLP analyses. Thus, AFLP were able to detect polymorphisms with higher efficiency than RAPD (+15%) and isozyme (+34%). Data from the isozyme, RAPD and AFLP analyses were used to compute matrices of genetic similarities. The efficiency of the UPGMA for the estimation of genetic relatedness among varieties was supported by cophenetic correlation coefficients. The resulting values indicated that the distortion level for the estimated similarities was minimal. The correlation coefficients obtained by the Mantel matrix correspondence test, which was used to compare the cophenetic matrices for the different markers, showed that estimated values of genetic relationship given for isozyme and RAPD markers (r = 0.89), as well as for AFLP and RAPD markers (r = 0.82) were properly related. However, AFLP and isozyme data showed only moderate correlation (r = 0.63). Although the genetic variability found among the different cultivars was low, both RAPD and AFLP markers proved to be efficient tools in assessing the genetic diversity of rice genotypes. This revised version was published online in July 2006 with corrections to the Cover Date.  相似文献   
54.
The objective of this study was to assess the efficacy of two reduced doses vs a high/luteolytic dose of cloprostenol on luteolytic activity and synchronization of oestrus in cyclic goats. Experiment 1, included 24 goats randomly allocated to three groups: control group (group H) received a single high dose of cloprostenol (87.5 μg; 1.0 ml; i.m.) and M and L groups, which received half (43.75 μg; 0.5 ml) and a third (26.25 μg; 0.3 ml) of the highest dose, respectively. Experiment 2, included 24 goats randomly assigned to the same experimental groups. Each group was treated using two injections of cloprostenol administered 10 days apart to synchronize oestrus. Transrectal ultrasonographic scanning (US) was performed to detect the presence, size and development of corpora lutea and ovarian follicles. Furthermore, detection of oestrus was performed every 12 h between 24 and 72 h after the second injection of cloprostenol, and the luteolytic effect was verified by US. In Experiment 1, all goats that had corpora lutea at timing of treatment regressed their corpora lutea. In Experiment 2, the occurrence of oestrus and the interval between treatment to onset of oestrus were: 100%, 49.5 ± 3.0 h; 100%, 51.0 ± 3.0 h; and 75%, 56.0 ± 3.5 h for H, M and L groups, respectively. The development of preovulatory follicles and occurrence of subsequent corpora lutea were similar among groups. In summary, the use of 26.25 μg of cloprostenol is effective for the synchronization of oestrus in cyclic goats.  相似文献   
55.
Biosecurity risks are a major threat to the profitability of the industry as well as impacting human and animal health. Livestock producers play a crucial role in biosecurity as the first to notice changes in the health or productivity of their stock and are generally responsible for implementing protective measures. However, uptake of biosecurity measures by producers is variable. We critically appraised the current literature regarding biosecurity practices in Australian livestock industries and highlight aspects that are well understood as well as those where further research or information is needed. Findings from 12 cross-sectional studies suggest that Australian producers' knowledge of biosecurity methods and importance might have a positive influence on their willingness to implement or incorporate biosecurity practices. There is moderate evidence supportive of biosecurity being well understood by livestock producers across Australia. Barriers to producers using biosecurity practices included lack of information or communication from agricultural, veterinary or government organisations. It was found that larger stock numbers were positively correlated with biosecurity implementation and that producers used veterinarians, government and industry agencies as resources for trusted information.  相似文献   
56.
To expand the potential of pseudopterosins and seco-pseudopterosins isolated from the octocoral Pseudopterogorgia elisabethae of San Andrés and Providencia islands (southwest Caribbean Sea), we report the anti-microbial profile against four pathogenic microorganisms (Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa and Candida albicans) and report a more complete cytotoxic profile against five human cells lines (HeLa, PC-3, HCT116, MCF-7 and BJ) for the compounds PsG, PsP, PsQ, PsS, PsT, PsU, 3-O-acetyl-PsU, seco-PsJ, seco-PsK and IMNGD. For the cytotoxic profiles, all compounds evaluated showed moderate and non-selective activity against both tumor and normal cell lines, where PsQ and PsG were the most active compounds (GI50 values between 5.8 μM to 12.0 μM). With respect to their anti-microbial activity the compounds showed good and selective activity against the Gram-positive bacteria, while they did not show activity against the Gram-negative bacterium or yeast. PsU, PsQ, PsS, seco-PsK and PsG were the most active compounds (IC50 2.9–4.5 μM) against S. aureus and PsG, PsU and seco-PsK showed good activity (IC50 3.1–3.8 μM) against E. faecalis, comparable to the reference drug vancomycin (4.2 μM).  相似文献   
57.
Objective The present study investigated the foot health of the Kaimanawa feral horse population and tested the hypotheses that horses would have a large range of foot morphology and that the incidence of foot abnormality would be significantly high. Procedures Abnormality was defined as a variation from what the two veterinarian assessors considered as optimal morphology and which was considered to impact negatively on the structure and/or function of the foot. Fifteen morphometric variables were measured on four calibrated photographic views of all four feet of 20 adult Kaimanawa feral horses. Four morphometric variables were measured from the lateromedial radiographs of the left forefoot of each horse. In addition, the study identified the incidence of gross abnormality observed on the photographs and radiographs of all 80 feet. Results There was a large variation between horses in the morphometric dimensions, indicating an inconsistent foot type. Mean hoof variables were outside the normal range recommended by veterinarians and hoof care providers; 35% of all feet had a long toe conformation and 15% had a mediolateral imbalance. Abnormalities included lateral (85% of horses) and dorsal (90% of horses) wall flares, presence of laminar rings (80% of horses) and bull-nose tip of the distal phalanx (75% of horses). Both hypotheses were therefore accepted. Conclusions The Kaimanawa feral horse population demonstrated a broad range of foot abnormalities and we propose that one reason for the questionable foot health and conformation is lack of abrasive wearing by the environment. In comparison with other feral horse populations in Australia and America there may be less pressure on the natural selection of the foot of the Kaimanawa horses by the forgiving environment of the Kaimanawa Ranges. Contrary to popular belief, the feral horse foot type should not be used as an ideal model for the domestic horse foot.  相似文献   
58.
Tramadol is a centrally acting analgesic with opioid and monoaminergic actions. Its clinical effects have been well characterized in humans, where it has been in use for many years, but little is known for veterinary species. This study evaluated the sedative, emetic, thiopental‐sparing and intraoperative respiratory and hemodynamic effects of tramadol in comparison to morphine for pre‐medication of dogs undergoing orthopedic surgery under halothane anesthesia. Sixteen adult, healthy, mixed breed dogs (8.0 ± 2.6 kg) were studied. Eight dogs were pre‐medicated with tramadol (1.0 mg kg‐1 IM) and the other eight with morphine (1.0 mg kg–1 IM). After 20 minutes, anesthesia was induced with thiopental and subsequently maintained with halothane in oxygen using a Bain system, with spontaneous respiration. Degree of sedation and occurrence of emesis were evaluated after pre‐anesthetic medication. Dose of thiopental necessary for tracheal intubation was compared between the two groups. Arterial blood gas analyzes were done before pre‐medication and at 60 minutes of anesthesia. Heart rate and noninvasive arterial blood pressure were recorded before pre‐medication and every 10 minutes during anesthesia. Observer was blinded of the treatment given for each dog. Tramadol produced no visible sedation and no vomiting, while morphine induced a moderate degree of sedation in all dogs and vomiting in 62% of them. Dogs pre‐medicated with tramadol required significantly more thiopental (17 ± 3.8 mg kg–1) for induction of anesthesia than those pre‐medicated with morphine (12 ± 1.8 mg kg–1). Pre‐medication with morphine was associated with significantly higher PaCO2 and lower pH at 60 minutes of anesthesia. The remaining respiratory parameters and the hemodynamic variables were similar between the two groups. In conclusion, dogs pre‐medicated with tramadol at 1 mg kg–1 IM do not become visibly sedated and require a greater amount of thiopental for induction of anesthesia than pre‐medication with morphine. As intraoperative respiratory function is better preserved with tramadol, it may be useful for pre‐medication of respiratory compromised patients.  相似文献   
59.
This study evaluated P. edulis f. edulis intraspecific variation at DNA level using AFLPs and SSRs. About 60 specimens were collected from Colombian commercial plantations in the departments of Antioquia, Boyacá, Cundinamarca, Huila, Quindío and Tolima. Ten specimens were also included from Corpoica’s La Selva research center Passiflora germplasm bank. A non-commercial purple passion fruit plant and three species from the Passiflora genus (Passiflora maliformis, Passiflora edulis f. flavicarpa and Passiflora ligularis) were included as controls. The six most informative ones were selected from the initial screening of 49 different AFLP primer combinations; 52–92 DNA fragments for each combination in each genotype (total 419 fragments) were obtained by using these six combinations. 17 SSR primers reported in P. edulis f. flavicarpa and Passiflora alata were tested on purple passion fruit. Eight of them were successfully amplified but none showed polymorphism. Relationships among individuals were assessed on AFLP data using cluster analysis by Dice coefficient, UPGMA algorithm and the multiple correspondence analysis ordination method based on Greenacre measurement. The similarity coefficients ranged from 0.75 to 1.00 giving an average of 0.96 within the different purple passion fruit materials, showing low genetic variability for the purple passion fruit material used in this study.  相似文献   
60.
The objective of the present study was to investigate the influence of different sucrose‐based extenders on the motility, morphology, viability and acrosomal integrity of epididymal cat spermatozoa cryopreserved by ultra‐rapid freezing method. Nine cats were castrated, and collected semen was diluted 1 : 1 with Dulbecco`s phosphate‐buffered saline‐BSA1%‐based extender supplemented with different sucrose concentrations (0, 0.25, 0.4 and 0.6 m ). After ultra‐rapid freezing, samples were thawed and sperm motility, morphology, viability and acrosome status were assessed. At thawing, the number of progressively motile (p < 0.01) and morphologically normal (p < 0.01) sperm was higher in the sucrose‐supplemented groups than in the sucrose‐free group. Viability of spermatozoa cryopreserved without sucrose was significantly reduced. In extender supplemented with 0.4 m sucrose, spermatozoa viability showed higher values (57.0 ± 4.7; p < 0.01). No significant differences were detected among groups for sperm acrosome integrity. Results support that cat sperm survive after ultra‐rapid freezing using sucrose as a cryoprotectant, and the best results were achieved when 0.4 m of sucrose was used. This is the first report on sperm ultra‐rapid freezing of cat sperm and further studies on extenders, sperm management or cryovials should be carried out to improve sperm cryosurvival.  相似文献   
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