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101.
The effects of dietary supplements of virginiamycin on the behaviour and physiology of 17 thoroughbred geldings (five cribbers, six weavers and six control horses) were compared with the effects of a placebo over a period of 16 weeks. Virginiamycin had no effect on the horses' stereotypic behaviour, but it reduced their explorative behaviour, possibly owing to a reduction in feeding motivation. Virginiamycin increased the water intake of the cribbers and decreased the water intake of the control horses, but it was not possible to eliminate possible confounding factors for this effect. Virginiamycin had no other significant effects on the behaviour or physiology of the horses, and had no effect on the digestibility of their diets.  相似文献   
102.
Objective The hypothesis was that Visual Analog Scale (VAS) scores would be lower, and mechanical wound thresholds (MWT) higher, in cats receiving tolfenamic acid compared to those receiving placebo in the postoperative period following elective ovariohysterectomy. Animals Sixty‐nine client‐owned cats. Methods A prospective, randomized, blinded and placebo‐controlled study was performed in cats which underwent ovariohysterectomy following preoperative tolfenamic acid, meloxicam, or placebo. A second dose of the same analgesic was administered 24 hours postoperatively. Assessments were made 1‐hour before induction and 1, 2, 4, 6, 22, and 25 hours postoperatively. Pain was assessed by a blinded observer using Numerical Rating (NRS) and VAS scales. The MWT were measured using a force‐measuring device. Group comparison was performed by using one‐way anova and chi‐squared test for qualitative and quantitative data, respectively, and a mixed model for repeated measurements (p < 0.05). Results Sixty‐five cats were included in the study. There were no differences between groups at baseline. There was a treatment effect on the NRS scores at 6, 22 and 25 hours. The meloxicam group was less painful than controls at 6 and 22 hours; both treatment groups were less painful than controls at 25 hours. There were no differences between groups in VAS for pain or sedation. The number of animals receiving rescue analgesia did not differ between groups. There was a treatment effect on MWT; thresholds in both treatment groups were significantly higher than that observed in controls at all time points. Conclusions Preoperative tolfenamic acid or meloxicam reduced wound sensitivity following ovariohysterectomy in the cat. Clinical relevance Tolfenamic acid and meloxicam administered preoperatively provided a similar analgesic effect in the postoperative period lasting 24 hours. Mechanical thresholds may be a better way of evaluating postoperative analgesia provided by nonsteroidal anti‐inflammatory drugs in cats.  相似文献   
103.
An indirect ELISA test was developed for the diagnosis of Brucella canis infection in dogs. A bacterial whole cell extract was used as a solid phase antigen, using B. canis isolated from an infected animal. Sera from culture-positive and healthy negative animals were used as internal reference controls. The cut-off point was determined by a mathematical formula for a statistically valid value, which defined the upper prediction limit, based on the upper tail of the t-distribution of 21 negative control sera readings, for the confidence level of 99.5%. The sensitivity and specificity of the ELISA test were 95% and 91%, respectively. The ELISA test showed a significant concordance index (K=0.84) with the agar gel immunodiffusion test. The reliability of the ELISA for the detection of infected animals was established by a double blind study testing 280 sera provided by serum banks from different diagnostic and research institutions and analyzed by ROC Curve.  相似文献   
104.
Sheep and dog blood samples were collected from nine farms in the county of Guarapuava, Paraná, Brazil. The indirect fluorescent antibody test (IFAT) was used to detect Neospora caninum and Toxoplasma gondii antibodies. Herein, serum samples from 305 sheep were evaluated, being 29 (9.5%) and 157 (51.5%) seropositives to N. caninum and T. gondii, respectively. Seven (29.1%) and five (20.8%) out of 24 dogs were seropositives to N. caninum and T. gondii, respectively. There were no differences among the sheep serology for N. caninum and reproductive problems, management and animal feeding variables, neurological problems and presence of other animals species on the farm (P>or=0.05). The simultaneous frequency of antibodies between N. caninum and T. gondii was 5.2% in the herds. Age, breed, farm size, semi-intensive activity, mineral salt supplementation, water origin, stage of the pregnancy when reproduction problems occurred, neurological problems in lambs, presence of rodents in the food room and pasture cat access were identified as associated factors for the occurrence of toxoplasmosis in sheep (P<0.05). There were no differences among the seropositivity in dogs for N. caninum and T. gondii and breed, age and sex (P>or=0.05). The present work is the first report on serum prevalence of N. caninum in sheep from the state of Paraná, Brazil.  相似文献   
105.
This work evaluated how pine plantations established on old fields and degraded lands influence soil properties in comparison with adjacent unplanted areas that undergo into secondary succession, and native forests, analysing the effects of abiotic variables and stand characteristics in the afforestation process. Thirty‐two paired sites (pine plantations versus unplanted areas) and 10 native forests were selected in the SE Spain. In total, 74 soil profiles were studied, and 222 composite soil samples were collected at three different depths. Soil organic carbon, cation exchange capacity, and C : N ratio showed significantly greater values in pine plantations in relation to the unplanted areas (0–5 cm), and the mean values of soil organic carbon, nitrogen (N), C : N ratio, and cation exchange capacity in these pine plantations were similar to those found under native forests. Only K+ concentrations were clearly higher in the native forests than in the other land uses for all depths analysed. Pine plantations in the drier and warmer areas showed lower soil quality in relation to the paired unplanted areas, as well as the younger and denser ones; it may be because under these situations, more time is needed to produce an improvement. In fact, the paired net variations increased with the stand age and/or tree size. In conclusion, pine plantations were in general more efficient in improving parameters related to soil quality, especially in locations with high soil water retention capacity, which in our study area were found at higher and cooler elevations. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   
106.
This study brings an integrated analysis about the relationship between water deterioration and its physiological consequences in live fish transport. The analysis was focused on the transport water and its deterioration, and physiological challenges imposed on the fish. Usual commercial handling procedures employed to mitigate fish stress during transport were discussed. Future topics of research for the establishment of safer fish transport protocols were proposed. Transport was classified into short (≤8 h) or long transport (>8 h). The main issue in short transports should be the prevention of water pH reduction, while in long transports it is the increase in ammonia. Plasma cortisol is the most employed marker for stress and is acutely elevated upon short episodes of transport, but remains elevated even in long‐transport events. Plasma glucose is perhaps a better marker for handling stress. Plasma lactate, pH, osmolality CO2 and ions should be more often evaluated. Plasma Na+ and Cl are very useful markers of acidosis, due to their respective exchange for H+ and , for acid–base regulation. The establishment of species‐specific transport protocols should be preceded by such combined analyses of water and physiological parameters.  相似文献   
107.
Sharks are very sensitive to stress and prone to a high mortality rate after capture. Since approximately 50 million of sharks are caught as bycatch every year, and current recommendations to reduce the impact of commercial fishing strongly support immediate release, it is imperative to better understand post-release mortality caused by the stress of capture and handling. Blood samples allow the assessment of stress levels which are valuable tools to reduce mortality in commercial, recreational and scientific fishing, being essential for the improvement in those conservation measures. Biochemical analyses are widely used for sharks as stress indicators, with secondary plasma parameters (lactate, glucose and ions) being the most often employed assays. However, it is virtually impossible to determine baseline plasma parameters in free-ranging sharks, since blood withdrawal involves animal capture and restrain, which are stressful procedures. This study aims at analyzing secondary parameters of five healthy tiger sharks captured with circular hooks and handlines in Fernando de Noronha (Northeastern Brazil) and comparing them with secondary parameters of three dead tiger sharks caught off Recife (also Northeastern Brazil). The results showed that the analysis of some plasma constituents in dead animals may be an efficient tool to assess stress and lethality. However, traditional parameters such as glucose and calcium, need to be used with caution. The results also demonstrated the extreme importance of urea and phosphorus for assessing stress response and mortality in tiger sharks, both parameters frequently neglected and of utmost importance for shark’s homeostasis.  相似文献   
108.
–  • Multivariate statistical analysis was used to define different developmental stages for stone pine (Pinus pinea L.) considering tree size and cone production, without site-specific information.  相似文献   
109.
Eucalyptus globulus wood was subjected first to HCl–catalysed delignification with 70% acetic acid under conditions realizing an incomplete 3 × 3 × 3 factorial design (HCl concentration 0, 0.025 or 0.05%; temperature 120, 140 or 160 °C; reaction time 1, 2.5 or 4 h), and then to enzymatic hydrolysis. The hydrolysis kinetics conformed to both Ghose's empirical model and a biexponential equation. The biexponential fit implies the presence of both readily and reluctantly hydrolysed cellulose fractions, and the fitted coefficients show hydrolysis yield to depend largely on the digestibility of the latter. Multiple regression of performance variables on pulping conditions showed that neither the rate nor the extent of hydrolysis is greatest for pulps with minimum lignin or xylose contents; we attribute this circumstance to the condensation and precipitation of lignin under severe pulping conditions, which protects the cellulose of the pulp from enzymatic attack. Received 20 June 1998  相似文献   
110.
ABSTRACT:   Ensis arcuatus and Ensis siliqua are the most economically important species of razor clams in the European Union. Due to similarities between their shell morphology, and the differing retail value, these species are often misidentified. Therefore, it is necessary to develop an appropriate protocol to allow accurate differentiation between these species of razor clam in order to protect consumer rights, avoid commercial fraud (whether intentional or unintentional), and to enforce labeling and safety regulations. With the aim of developing a rapid and reliable method of differentiation, individuals of E. arcuatus and of E. siliqua were examined by polymerase chain reaction restriction fragment polymorphism (PCR–RFLP) using the internal transcribed spacer region 1 (ITS1). A species-specific restriction endonuclease pattern was found with the enzyme Ksp I for both species, allowing their exact identification. Thus, this work provides a simple, reliable and rapid protocol for accurate discrimination between E. arcuatus and E. siliqua , which proves useful for traceability and enabling the enforcement of labeling regulations.  相似文献   
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