Tramadol improved the efficacy of ketamine–xylazine anaesthesia in young pigs

ObjectiveTo evaluate the influence of premedication with tramadol on xylazine–ketamine anaesthesia in young pigs.Study designProspective, randomized, blinded cross-over study.AnimalsTen young Niger hybrid pigs: mean weight 6.1 ± 0.6 kg.MethodsPigs were anaesthetized twice. Xylazine (2.5 mg kg^?1), ketamine (25 mg kg^?1) and atropine (0.04 mg kg^?1) were administered by intramuscular (IM) injection, 5 minutes after either tramadol (5 mg kg^?1)) (treatment XKT) or saline (treatment XKS). Time to loss of righting reflex (TLRR), duration of antinociception, duration of recumbency (DR) and recovery times (RCT) were recorded. Quality of induction of anaesthesia including ease of endotracheal intubation was assessed using a subjective ordinal rating score of 1 (worst) to 4 (best). Heart, pulse and respiratory rates, arterial oxygen saturations and rectal temperatures were determined over 60 minutes. Antinociception was assessed by the pigs’ response to artery forceps applied at the interdigital space. Data were compared with Student's t-test, Mann–Whitney's test or analysis of variance (anova) for repeated measures as appropriate and are presented as mean ± standard deviation.ResultsThe quality of anaesthetic induction was significantly better and duration of antinociception significantly longer (p < 0.05) in treatment XKT (3.1 ± 0.7 score; 43.7 ± 15.5 minutes) than in treatment XKS (2.8 ± 0.6 score; 32.0 ± 13.3 minutes). TLRR, DR and RCT did not differ significantly (p > 0.05) between treatment XKT (2.1 ± 0.8, 65.8 ± 17.0 and 13.2 ± 6.7 minutes) and treatment XKS (2.1 ± 1.3, 58.0 ± 14.8 and 10.3 ± 5.6 minutes). Physiological measurements did not differ between the treatments.Conclusion and clinical relevanceTramadol improved the quality of anaesthetic induction and increased the duration of antinociception in xylazine–ketamine anaesthetized young pigs without increasing duration of anaesthesia, nor causing additional depression of the physiological parameters measured.     

Effects of high and low inspired fractions of oxygen on horse erythrocyte membrane properties, blood viscosity and muscle oxygenation during anaesthesia

ObjectivesTo evaluate whether a period of hyperoxia or after a period of hypoxia produced changes attributable to reactive oxygen species in anaesthetized horses.Study designProspective randomized experimental study.AnimalsSix healthy (ASA I) geldings, aged 4.5–9.5 years and weighing 510–640 kg^?1.MethodsAfter 30 minutes breathing air as carrier gas for isoflurane, horses were assigned randomly to breathe air as carrier gas (CG0.21) or oxygen as carrier gas (CG1.00) for a further 90 minutes. After an interval of 1 month each horse was re-anaesthetized with the other carrier gas for the 90 minute test period. Ventilation was controlled throughout anaesthesia. Arterial blood was sampled to measure gas tensions, lactate, cholesterol, vitamin E, 4-hydroxy-alkenals, 8-epi-PGF_2α, half haemolysis time, half erythrolysis time, and erythrocyte membrane fluidity. Muscle blood flow and oxygenation were evaluated by near infrared spectroscopy and coloured Doppler.ResultsAfter the first 30 minutes horses were hypoxemic. Subsequently the CG1.00 group became hyperoxaemic (PaO₂～240 mmHg) whereas the CG0.21 group remained hypoxaemic (PaO₂～60 mmHg) and had increased lactate concentration. No significant changes in vitamin E, 4-hydroxy-alkenals, or 8-epi-PGF_2α concentrations were detected. During the 90 minute test period the CG0.21 group had increased resistance to free-radical-mediated lysis in erythrocytes, whereas the CG1.00 group had slightly decreased resistance of whole blood to haemolysis. CG0.21 induced a progressive muscle deoxygenation whereas CG1.00 induced an increase in muscle oxygen saturation followed by progressive deoxygenation towards baseline.Conclusions and clinical relevanceDuring isoflurane anaesthesia in horses, the hyperoxia induced by changing from air to oxygen induced minimal damage from reactive oxygen species. Using air as the carrier gas decreased skeletal muscle oxygenation compared with using oxygen.     

Effects of tramadol on the minimum alveolar concentration of sevoflurane in dogs

ObjectiveTo evaluate the effect of tramadol on sevoflurane minimum alveolar concentration (MAC_SEVO) in dogs. It was hypothesized that tramadol would dose-dependently decrease MAC_SEVO.Study designRandomized crossover experimental study.AnimalsSix healthy, adult female mixed-breed dogs (24.2 ± 2.6 kg).MethodsEach dog was studied on two occasions with a 7-day washout period. Anesthesia was induced using sevoflurane delivered via a mask. Baseline MAC (MAC_B) was determined starting 45 minutes after tracheal intubation. A noxious stimulus (50 V, 50 Hz, 10 ms) was applied subcutaneously over the mid-humeral area. If purposeful movement occurred, the end-tidal sevoflurane was increased by 0.1%; otherwise, it was decreased by 0.1%, and the stimulus was re-applied after a 20-minute equilibration. After MAC_B determination, dogs randomly received a tramadol loading dose of either 1.5 mg kg^?1 followed by a continuous rate infusion (CRI) of 1.3 mg kg^?1 hour^?1 (T1) or 3 mg kg^?1 followed by a 2.6 mg kg^?1 hour^?1 CRI (T2). Post-treatment MAC determination (MAC_T) began 45 minutes after starting the CRI. Data were analyzed using a mixed model anova to determine the effect of treatment on percentage change in baseline MAC_SEVO (p < 0.05).ResultsThe MAC_B values were 1.80 ± 0.3 and 1.75 ± 0.2 for T1 and T2, respectively, and did not differ significantly. MAC_T decreased by 26 ± 8% for T1 and 36 ± 12% for T2. However, there was no statistically significant difference in the decrease between the two treatments.Conclusion and clinical relevanceTramadol significantly reduced MAC_SEVO but this was not dose dependent at the doses studied.     

Efficacy of a 5-day extended therapy program during lactation with cephapirin sodium in dairy cows chronically infected with Staphylococcus aureus

This study determined the efficacy of a 5-day extended therapy with cephapirin sodium in dairy cows chronically infected with Staphylococcus aureus. Chronically infected cows selected from 14 dairy herds in the St-Hyacinthe region, Québec were randomly allocated to a group of 31 cows treated for 5 consecutive days with 200 mg of cephapirin per quarter BID or a group of 30 untreated control cows. Bacteriological cure was determined by 3 negative bacterial cultures at 10, 24, and 31 days after treatment. The cow cure rates were 25.8% (8/31) in the treated cows and 3.3% (1/30) in the control group (P = 0.013). The quarter cure rates at first sampling post-treatment were 77.6% (38/49) and 18% (9/50) in the treated and the control groups, respectively (P < 0.0001). A 5-day extended therapy with cephapirin is effective in treating cows chronically infected with S. aureus.     

Evaluation of a Collagenase Generated Osteoarthritis Biomarker in Naturally Occurring Canine Cruciate Disease

Objective— To determine the clinical value of a novel osteoarthritis (OA) biomarker in detecting canine cruciate disease.
Study Design— Cross sectional clinical study.
Animals— Dogs (n=22) with cranial cruciate ligament (CCL) rupture and 12 control dogs.
Methods— Concentrations of collagenase-generated cleavage epitope of type II collagen (Col2-3/4C_{long mono}, or C2C) in serum, urine, and joint fluid were compared between a group of dogs with CCL rupture and a control group. Correlation of C2C concentrations to the clinical stage of stifle OA was also evaluated.
Results— There were no significant differences in C2C concentrations in serum, urine, and joint fluid between groups ( P >.05). Subjective scores of lameness, joint effusion, osteophytosis were significantly more severe in the CCL rupture group compared with the control group ( P <.05). There was no significant correlation of C2C concentrations with clinical stage of stifle OA ( P >.05).
Conclusion— This OA biomarker did not detect pathology associated with CCL rupture. Our results suggest that collagenase-specific degradation of type II collagen in articular cartilage may not be involved in the early stage of naturally occurring canine cruciate disease, and that pathology associated with naturally occurring CCL rupture is different from that of experimental OA model.
Clinical Relevance— C2C is not clinically useful in detecting CCL rupture in dogs.     

Effect of paratuberculosis on the diagnosis of bovine tuberculosis in a cattle herd with a mixed infection using interferon-gamma detection assay

Interferon-gamma (IFN-gamma) detection assay is being applied as an ancillary test to tuberculin tests in the diagnosis of bovine tuberculosis to detect the maximum number of infected animals. Among possible factors influencing the performance of tuberculosis-diagnostic tests, paratuberculosis, a widespread disease in Spain and other European countries, has been pointed out as a cause of false positive reactions. Still, its effect on the sensitivity of these tests in cattle has yet to be fully characterized. The impact of paratuberculosis in the apparent sensitivity of IFN-gamma assay was studied in a bullfighting cattle herd with a mixed tuberculosis-paratuberculosis infection, using culture of Mycobacterium bovis and Mycobacterium avium paratuberculosis as the gold standard to determine the infection status of every animal. A total of 218 animals were slaughtered and sampled for bacteriology after blood sampling. IFN-gamma assay showed a lower apparent sensitivity in animals with a mixed infection (50%) compared to all animals suffering tuberculosis (78.3%). This finding indicates that the presence of paratuberculosis in tuberculosis-infected herds could imply a serious impairment in the sensitivity of IFN-gamma detection test.     

Collection Rates and Morphology of Equine Oocytes Obtained from Immature Follicles after Treatment with Equine Pituitary Extract (EPE) and Human Chorionic Gonadotropin

This study examined the effect of treating mares with equine pituitary extract (EPE) in combination with human chorionic gonadotropin (hCG; EPE/hCG) on the recovery rate of immature oocytes by ovum pick-up (OPU) and on oocyte morphology. Ten mares were subjected to each of two treatments in a random sequence: superstimulated with EPE (25 mg, twice daily) and treated with hCG (2,500 IU) or control (no exogenous treatment). The cytoplasmic morphology of oocytes recovered was evaluated through transmission electron microscopy. Follicular fluid was collected at aspiration for progesterone analysis, which was performed by radioimmunoassay. The EPE/hCG did not increase the oocyte recovery rate from immature follicles when compared with the controls (15.5% and 16.7%, respectively). A significantly higher oocyte recovery rate per mare was observed (70% versus 50%). However, precocious granulosa cell expansion was observed with EPE/hCG treatment in contrast to the control (64.4% and 33% of follicles with expanded cumulus, respectively), and increased intrafollicular progesterone concentration was also seen (158.80 ng/mL versus 82.05 ng/mL). The ultrastructural analysis of oocytes from both groups showed morphologic features related to immaturity. Numerous vesicles containing cortical granules were found, distributed in clusters into the cytoplasm, and junctional complexes were still seen between oocyte and granulosa cells. In conclusion, EPE/hCG treatment induced some follicular modifications, but the recovery rate was not increased. All oocytes examined presented signs of immaturity.     

Chromoplast morphology and beta-carotene accumulation during postharvest ripening of Mango Cv. 'Tommy Atkins'

Accumulation of beta-carotene and trans-cis isomerization of ripening mango mesocarp were investigated as to concomitant ultrastructural changes. Proceeding postharvest ripening was shown by relevant starch degradation, tissue softening, and a rising sugar/acid ratio, resulting in a linear decrease (R (2) = 0.89) of a ripening index (RPI(KS)) with increasing ripening time. A modest accumulation of all-trans-beta-carotene and its cis isomers resulted in a slight pigmentation of the mango chromoplasts, because ambient temperatures of 18.2-19.5 degrees C provided suboptimal ripening conditions, affecting color development and beta-carotene biosynthesis. The ultrastructures of chromoplasts from mango mesocarp and carrot roots were comparatively studied by means of light and transmission electron microscopy. Irrespective of the ripening stage, mango chromoplasts showed numerous plastoglobuli varying in size and electron density. They comprised the main part of carotenoids, thus supporting the partial solubilization of the pigments in lipid droplets. However, because different pigment-carrying tubular membrane structures were also observed, mango chromoplasts were assigned to the globular and reticulotubular types, whereas the crystalline type was confirmed for carrot chromoplasts. The large portions of naturally occurring cis-beta-carotene in mango fruits contrasted with the predominance of the all-trans isomer characteristic of carrots, indicating that the nature of the structure where carotenoids are deposited and the physical state of the pigments are crucial for the stability of the all-trans configuration.     

Fourteen years of applying zero and conventional tillage,crop rotation and residue management systems and its effect on physical and chemical soil quality

Soil management systems may negatively affect the quality of the soil. Policymakers and farmers need scientific information to make appropriate land management decisions. Conventional (CT) and zero tillage (ZT) are two common soil management systems. Comparative field studies under controlled conditions are required to determine the impact of these systems on soil quality and yields. The research presented studied plant and soil physical and chemical characteristics as affected by different agricultural management practices, i.e. ZT and CT, cropped with continuous wheat or maize in monoculture (M) or in a yearly rotation (R) of these two crops, either with residue retention (+r) or without residues retention (?r), in an experimental field in the Transvolcanic Belt of Mexico after 14 years. The dominant factors defining soil quality were organic C, total N, moisture, aggregate stability, mechanical resistance, pH and EC. The principal component combining the variables organic C, total N, aggregate stability and moisture content showed the highest correlations with final yield (R = 0.85 for wheat and 0.87 for maize).After 14 years of continuous practice, ZTM + r and ZTR + r had the best soil quality and produced the highest wheat and maize yields of average 2001–2004 (6683 and 7672 kg ha^?1 and 5085 and 5667 kg ha^?1, respectively). Removing the residues, i.e. treatments ZTM ? r with maize (average 2001–2004: 1388 kg ha^?1) and ZTR ? r and CTR ? r with wheat (average 2001–2004: 3949 and 5121 kg ha^?1), gave the lowest yields and less favourable soil physical and chemical characteristics compared to the other practices. It was found that zero tillage with residue retention is a feasible management technology for farmers producing maize and wheat in the agro-ecological zone studied, resulting in a better soil quality and higher yields than with the conventional farmer practice (maize monoculture, conventional tillage and residue removal).