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161.
The aim of this study was to compare four identification procedures to detect Dichelobacter nodosus and develop a rapid, simple and effective method to identify D. nodosus strains isolated from cases of ovine footrot. The four methods used were: (a) the classic guidelines set down by Holdeman et al. (1977) and Summanen et al. (1993) which are based on gas liquid chromatography (GLC) and different biochemical tests, this method was considered as landmark; (b) Baron and Citron's flowchart for the rapid identification of Gram-negative rod-shaped anaerobes (1997); (c) the API rapid 32 A system (bio Mérieux), and (d) Mast ID Anaerobe ID Ring (MID8) (Mast Diagnostics). None of the four methods used allowed us to correctly identify the D. nodosus strains (neither the strains isolated from cases of ovine footrot nor those originating from type collection). Because of the difficulties encountered in obtaining a correct identification of D. nodosus, we propose a simple, rapid and effective way to achieve this task. Our flowchart will provide the means to identify this microorganism in any laboratory of general microbiology without having to use any specialised equipment.  相似文献   
162.
OBJECTIVE: To determine pharmacokinetic parameters for meloxicam, a nonsteroidal anti-inflammatory drug, in horses. ANIMALS: 8 healthy horses. PROCEDURE: In the first phase of the study, horses were administered meloxicam once in accordance with a 2 x 2 crossover design (IV or PO drug administration; horses fed or not fed). The second phase used a multiple-dose regimen (daily oral administration of meloxicam for 14 days), with meloxicam administered at the recommended dosage (0.6 mg/kg). Plasma and urine concentrations of meloxicam were measured by use of validated methods with a limit of quantification of 10 ng/mL for plasma and 20 ng/mL for urine. RESULTS: Plasma clearance was low (mean +/- SD; 34 +/- 0.5 mL/kg/h), steady-state volume of distribution was limited (0.12 +/- 0.018 L/kg), and terminal half-life was 8.54 +/- 3.02 hours. After oral administration, bioavailability was nearly total regardless of feeding status (98 +/- 12% in fed horses and 85 +/- 19% in nonfed horses). During once-daily administration for 14 days, we did not detect drug accumulation in the plasma. Meloxicam was eliminated via the urine with a urine-to-plasma concentration that ranged from 13 to 18. Concentrations were detected for a relatively short period (3 days) after administration of the final daily dose. CONCLUSIONS AND CLINICAL RELEVANCE: Results of this study support once-daily administration of meloxicam regardless of the feeding status of a horse and suggest a period of at least 3 days before urine concentrations of meloxicam reach concentrations that could be used in drug control programs.  相似文献   
163.
OBJECTIVE: To develop a technique for use in investigation of healing of long-bone defects by creation of a critical-size defect in the left metarsal III and IV bone (metatarsus) of sheep. ANIMALS: 18 healthy adult sheep. PROCEDURE: Sheep were allocated to 4 groups (3, 3, 5, and 7 sheep in groups 1 to 4, respectively). An ostectomy with various segmental length-to-diaphyseal diameter ratios (0.5, 1.0, 2.0, and 2.0 for groups 1 to 4, respectively) was performed on the left metatarsus of each sheep. The defect was left empty in sheep of groups 1, 2, and 3, whereas the defect was filled with a massive corticocancellous bone autograft in sheep of group 4. RESULTS: All sheep tolerated the surgical procedure well and were able to use the affected limb the day after surgery. Radiographic and histologic examinations conducted 16 weeks after surgery revealed nonunion in all sheep of groups 1, 2, and 3, whereas consistent bone healing with abundant bone formation was observed in all sheep of group 4. CONCLUSIONS AND CLINICAL RELEVANCE: Analysis of these findings suggests that the sheep metatarsal model is a critical-size defect model with low morbidity. It should allow the assessment of new technologies for bone regeneration in conditions closely mimicking the clinical setting. IMPACT FOR HUMAN MEDICINE: Use of this technique in sheep should be of benefit for the preclinical study of osteoconductive, osteoinductive, or osteogenic biomaterials for use in humans.  相似文献   
164.
Plasma clearance     
Plasma (total, systemic...) clearance is determined by all the individual metabolizing/eliminating organ clearances and involves mainly liver and kidney clearances. Plasma clearance (a volume per time, i.e. a flow) expresses the overall ability of the body to eliminate a drug by scaling the drug elimination rate (amount per time) by the corresponding plasma concentration level. The interpretation of plasma clearance and inter-species comparisons are made easier by computing the overall body extraction ratio (from 0 to 1), which is the ratio of the body clearance divided by cardiac output. Plasma clearance is the most important pharmacokinetic parameter because it is the only one which controls the overall drug exposure (for a given bioavailability) and it is the parameter which allows computation of the dosage required to maintain an average steady-state plasma concentration.  相似文献   
165.
Antimicrobial resistance is known to be an emerging problem, but the extent of the issue remains incomplete. The aim of this study was to determine the presence or absence of nine resistance genes (blaTEM, catI, mecA, qnrS, sulI, sulII, tet(A), tet(Q), vanA) in the faeces of 141 pigeons from four urban parks in Alajuela, Guadalupe, Tres Ríos and San José in Costa Rica. The genes were identified by real‐time PCR directly from enema samples. About 30% of the samples were positive for genes catI and sulI; between 13% and 17% were positive for qnrS, sulII, tet(A) and tet(Q); and 4% were positive for blaTEM. The mecA and vanA genes were not detected. The average of antimicrobial resistance genes detected per pigeon was 2. Eight different patterns of resistance were identified, without differences in the sampling areas, being the most common pattern 2 (sulII positive samples). During rainy season, the genes more frequently found were sulI and tet(A). In conclusion, the urban inhabiting pigeons tested are currently carrying antimicrobial resistance genes, potentially acting as reservoirs of resistant bacteria and vectors to humans. To the authors’ knowledge, this is the first study carried out on direct detection of resistance genes in the digestive metagenomes of pigeons.  相似文献   
166.

Objective

To assess the cardiopulmonary effects caused by reverse Trendelenburg position (RTP) at 5° and 10° in sevoflurane-anesthetized yearling steers.

Study design

Prospective, experimental study.

Animals

Eight Holstein steers aged (mean ± standard deviation) 12 ± 2 months and weighing 145 ± 26 kg.

Methods

In the first phase of the study, the individual minimum alveolar concentration (MAC) of sevoflurane was determined using electrical stimulation. In the second phase, the effects of RTP were assessed. The animals were anesthetized on three separate events separated by ≥7 days in an incomplete crossover design: control treatment using a table without tilt (RTP0); treatment with the table at 5° RTP (RTP5) and table tilted 10° RTP (RTP10). Subjects were physically restrained in dorsal recumbency on the table, which was already tilted according to each treatment. Anesthesia was induced with sevoflurane at 8% in 5 L minute–1 oxygen via face mask followed by maintenance with sevoflurane at 1.3 MAC and spontaneous breathing. Cardiopulmonary variables were obtained immediately after instrumentation (T0) and then after 30, 60, 120 and 180 minutes (T30, T60, T120 and T180, respectively).

Results

The mean sevoflurane MAC for the eight steers was 2.12 ± 0.31%. Cardiac output was lower at all time points and the systemic vascular resistance index was higher at T120 and T180 in RTP10 compared with RTP0. Oxygen consumption was lower at T0 and at T180 in RTP10 compared with RTP0 and at all time points except T30 compared with RTP5. Oxygen extraction was lower at T0 in RTP10 compared with RTP0 and RTP5, and at T60 and T180 compared with RTP5.

Conclusions and clinical relevance

RTP 5° and 10° did not improve ventilatory and oxygenation variables in sevoflurane-anesthetized steers when compared with no tilt, however the cardiovascular variables were adversely affected in RTP10.  相似文献   
167.

Objective

To investigate the effects of pneumoperitoneum alone or combined with an alveolar recruitment maneuver (ARM) followed by positive end-expiratory pressure (PEEP) on cardiopulmonary function in sheep.

Study design

Prospective, randomized, crossover study.

Animals

A total of nine adult sheep (36–52 kg).

Methods

Sheep were administered three treatments (≥10-day intervals) during isoflurane–fentanyl anesthesia and volume-controlled ventilation (tidal volume: 12 mL kg?1) with oxygen: CONTROL (no intervention); PNEUMO (120 minutes of CO2 pneumoperitoneum); PNEUMOARM/PEEP (PNEUMO protocol with an ARM instituted after 60 minutes of pneumoperitoneum). The ARM (5 cmH2O increases in PEEP of 1 minute duration until 20 cmH2O of PEEP) was followed by 10 cmH2O of PEEP until the end of anesthesia. Cardiopulmonary data were recorded until 30 minutes after abdominal deflation.

Results

PaO2 was decreased from 435–462 mmHg (58.0–61.6 kPa) (range of mean values in CONTROL) to 377–397 mmHg (50.3–52.9 kPa) in PNEUMO (p < 0.05). Quasistatic compliance (Cqst, mL cmH2O?1 kg?1) was decreased from 0.85–0.92 in CONTROL to 0.52–0.58 in PNEUMO. PaO2 increased from 383–385 mmHg (51.1–51.3 kPa) in PNEUMO to 429–444 mmHg (57.2–59.2 kPa) in PNEUMOARM/PEEP (p < 0.05) and Cqst increased from 0.52–0.53 in PNEUMO to 0.70–0.74 in PNEUMOARM/PEEP. Abdominal deflation in PNEUMO did not restore PaO2 and Cqst to control values. Cardiac index (L minute?1 m2) decreased from 4.80–4.70 in CONTROL to 3.45–3.74 in PNEUMO and 3.63–3.76 in PNEUMOARM/PEEP. Compared with controls, ARM/PEEP with pneumoperitoneum decreased mean arterial pressure from 81 to 68 mmHg and increased mean pulmonary artery pressure from 10 to 16 mmHg.

Conclusions and clinical relevance

Abdominal deflation did not reverse the pulmonary function impairment associated with pneumoperitoneum. The ARM/PEEP improved respiratory compliance and reversed the oxygenation impairment induced by pneumoperitoneum with acceptable hemodynamic changes in healthy sheep.  相似文献   
168.

Background

The moose (Alces alces) is an intensively managed keystone species in Fennoscandia. Several aspects of reproduction in moose have not been fully elucidated, including puberty, timing of mating and oestrus, and the length of the oestrus period. These aspects are relevant for an adaptive management of moose with respect to harvest, population size, demography and environmental conditions. Therefore, an investigation of female moose reproduction was conducted during the moose-hunting period in southern Sweden from 2008 to 2011.

Results

A total of 250 reproductive organs and information on carcass weight and age was collected from four different hunting areas (provinces of Öland, Småland, Södermanland, and Västergötland) in southern Sweden. The results showed that puberty in female moose varied with carcass weight, age, and time of season. The period for oestrous/mating lasted from about mid September to the beginning of November.

Conclusions

The oestrus period (predominantly for heifers) is longer than previously reported and was not finished when the hunting period started. Sampling the uterine cervix to detect spermatozoa was a useful method to determine if mating had occurred. To avoid hunting of moose during oestrus, we suggest that the hunting period should be postponed by at least 14 days in southern Sweden.  相似文献   
169.

The aim of the present study was to describe the strategies of the control of an outbreak of leptospiral infection in dairy cattle in Maranhão State, Northeastern Brazil. In the period from January to July 2015, 18 (17%) out of 106 cows presented abortion, six (5.7%) stillbirth, and 12 (11.3%) repeated estrus, totaling 24 animals with reproductive problems. The diagnosis of leptospirosis was based on serology (microscopic agglutination test—MAT), bacteriological culture, and polymerase chain reaction (PCR). Antibiotic therapy, vaccination protocols, and changes in management practices were suggested as control measures. Of all animals on the farm (n?=?280), 136 (48.6%) were seropositive for at least one serovar of Leptospira sp. No pure leptospiral culture was obtained. Eight of the animals with reproductive problems yielded positive PCR results (vaginal fluid of seven animals and urine and vaginal fluid of one animal). Genetic sequencing of a vaginal fluid/urine PCR-positive sample revealed Leptospira borgpetersenii. One year after the adoption of control measures, no reproductive problems were observed. Thus, leptospirosis probably caused the reproductive failures in the herd, and the control and prevention measures implemented were efficient in controlling the disease.

  相似文献   
170.

Enzootic nasal tumor (ENT) is a contagious neoplasm associated with enzootic nasal tumor virus (ENTV), which may induce disease in sheep (ENTV-1) and goats (ENTV-2). This study aimed to describe the occurrence of ENT in two Texel sheep (Ovis aries) from a 75-sheep flock, located in the city of Gravataí, southern Brazil. Animals used to be purchased from different origins, and no specific tests for disease monitoring or quarantine procedure were performed. Affected animals presented respiratory distress, anorexia with severe weight loss, and mucopurulent unilateral nasal discharge. Necropsy was performed in both animals and nasal cavity masses were observed. Histopathological analysis demonstrated an epithelial neoplasm compatible with nasal adenocarcinoma. PCR using a protocol that amplifies a 591 bp sequence of 5’LTR-gag region of ENTV1 was performed followed by DNA sequencing. Both samples were positive, and the sequences obtained presented highest identity (97%) with ENTV strain TN28 (GenBank accession number MH899613) detected in a Texel sheep from Scotland. This is the first report of ENTV-1 leading to enzootic nasal tumor in sheep in Latin America, which confirms the presence of the retrovirus in sheep flocks in the Brazilian territory.

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