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SUMMARY Three groups of 15 to 17 adult fallow does with some additional yearling does in 2 of the groups were treated to synchronise oestrous cycles, and mated. All does were scanned by ultrasound at 4 weeks of gestation and at weekly intervals from week 7 to week 14 of gestation. Growth rates of 13 foetal and uterine characters, which have been used for ageing foetuses of red deer, were similar for adult and yearling does and among the 3 groups. Transrectal ultrasound scanning was a reliable and accurate means of detecting pregnancy and of ageing foetuses of fallow deer during weeks 7 to 17 of pregnancy.  相似文献   
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Forestry variables are usually calculated at a forest managementunit scale. However, a region's forestry sector is affectedby various other factors that interact over space and time,many of which are not directly associated to silvicultural activitiesbut nonetheless play an important part in its development froma socio-economic or environmental point of view. To understanda region's forestry dynamics, and especially to predict itsfuture tendencies, we must include all the necessary variablesin a single database, calculated for spatial units that arestable over time and adequate for planning purposes. In ourstudy, we developed a Forest Geographic Information System forGalicia called ‘SIFGa’. We used it to examine 310variables describing the environment, population tendencies,land tenure and forest management in the Spanish autonomousregion of Galicia, at both council and parish levels. Resultsreveal the connections between our variables, which reflectthe changes the regional forestry sector has experienced inthe past, and explain its current situation. They also confirmthe heterogeneity of forestry in the area and the need to adaptforest-planning strategies to each study unit, as well as tothe entire region.  相似文献   
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Leptospirosis is a zoonosis, found worldwide, affecting many species of animals. We conducted a cross-sectional study to estimate the prevalence of Leptospira borgpetersenii sv Hardjo and Leptospira interrogans sv Pomona in cattle in dairy herds in South-Western Victoria, Australia. Fifty-three herds were enrolled in the study. Urine samples were collected from 15 late-lactation cows in each herd. A questionnaire was provided to herd managers at the time of each herd visit, asking them to describe the methods they used for controlling leptospirosis, including vaccination. Urine samples were pooled at the herd level and tested for leptospira spp. using real time PCR. Urine samples from individual cows within the positive pooled samples were then tested for Leptospira Hardjo and Leptospira Pomona using qPCR. Four of the 53 herds showed positive leptospirosis results giving an apparent prevalence of 8 (95% CI 2–18) leptospira-positive herds per 100 herds at risk. Based on the 53 completed questionnaires, leptospirosis vaccination programs were not compliant with label directions in 36 of the 52 vaccinated herds: 69 (95% CI 55–81) of 100 herd managers that routinely vaccinated for leptospirosis did not comply with label directions. One herd was completely unvaccinated. Based on our findings, we estimate that approximately 10% of dairy farms in South-Western Victoria are likely to be infected with leptospirosis. While most herds are vaccinating for leptospirosis, most are not doing so according to label directions. We conclude that herd managers need to be better educated regarding leptospirosis vaccination programs.  相似文献   
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Ephemeral fever remains a viral disease of considerable importance to many countries including Australia. The virus has been only partly characterised and still awaits final classification. Although BEF virus was first thought to contain 6 structural proteins there is increasing evidence to suggest that it contains the 5 proteins characteristic of the Rhabdoviridae. Although BEF is thought to be arthropod borne, the vector has yet to be identified but it is clear from the distribution of BEF that more than one vector is capable of transmitting the disease. Despite rigorous investigation of the clinical signs and the pathology of ephemeral fever, little progress has been made on the pathogenesis of the disease. This has been partly due to the difficulty of propagating BEF virus in vitro and the inability to define the site of replication. However, there is mounting evidence to suggest that BEF is immunopathologic in nature and that the clinical expression of the disease is influenced by the release of one or more mediators of inflammation. The disease is characterised by a number of haematological and biochemical changes and early and prolonged treatment with phenylbutazone is capable of reversing a number of these changes. The intravenous administration of calcium can now be considered a justifiable addition to the treatment regimen together with prolonged phenylbutazone therapy. The vaccines currently available are prepared from either live attenuated or killed virus and may be less than reliable. There appears to be a need for a reliable, inexpensive, cold-chain independent alternative vaccine.  相似文献   
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The pharmacokinetics of flunixin meglumine in the sheep   总被引:4,自引:0,他引:4  
Flunixin meglumine was administered intravenously and intramuscularly in sheep and the pharmacokinetics of the drug studied. Plasma concentrations of flunixin were measured by high performance liquid chromatography. The decline in plasma- flunixin concentration with time was best fitted by a triexponential equation. The pharmacokinetics following intravenous administration of 1.0 mg/kg indicate that flunixin has a rapid distribution half-life (t½π= 2.3 min), a slow body clearance rate (Clb= 0.6 ml/kg/min) and an elimination half-life of 229 min. Similarly, at 2.0 mg/kg, flunixin is rapidly distributed from the plasma, t½π= 2.7 min, has a slow body clearance rate (C/b = 0.7 mk/lg/min) and an elimination half-life of 205 min.
Following intramuscular injection flunixin is rapidly and well absorbed from the injection site. It had a mean maximum concentration ( C max) of ≫5.9 μg/ml when administered at a dose rate of 1.1 mg/kg, and a relative bioavailability of 70%. Plasma concentrations increase proportionally to dose over the range 1.1 mg/kg-2.2 mg/kg when administered by the intramuscular route.  相似文献   
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