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A 12-week-old female alpaca cria weighing 10 kg presented with a 2-month history of left hindlimb lameness associated with osteomyelitis and sequestration of the shaft and wing of the left ilium. The affected segment of the ilium was surgically removed. Bacteriological culture revealed a small number of mixed aerobic and anaerobic bacteria. The cria recovered well, was discharged from the hospital 8 days after surgery and was paddock sound without complications 8 months later. Osteomyelitis and sequestration of long bones has been reported in alpacas, but further investigation is necessary to define the prevalence and pathogenesis and to develop specific recommendations for prevention and treatment.  相似文献   
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AIM: To compare the rectal and I/V administration of tramadol in dogs, to assess both its pharmacokinetic properties and absolute bioavailability.

METHODS: After rectal administration via suppositories and I/V injection of tramadol (4 mg/kg), the concentration of tramadol and its main metabolites, O-desmethyl-tramadol (M1), N-desmethyl-tramadol (M2) and N,O-didesmethyl-tramadol (M5), were determined in plasma, using high-performance liquid chromatography (HPLC). A balanced cross-over study was used, involving six male Beagle dogs.

RESULTS: Plasma concentrations after rectal and I/V administration were fitted on the basis of mono- and bi-compartmental models, respectively. Following rectal administration tramadol was detected from 5 minutes up to 10 hours, in lesser amounts than M5 and M2, while M1 was detected in negligible amounts. Following I/V administration tramadol was detected up to 10 hours, M2 and M5 were detected at similar concentrations, and M1 was present at low concentrations. The area under the curve (AUC) of the three metabolites did not differ significantly after either route of administration of tramadol. The absolute bioavailability of tramadol via rectal administration was 10 (SD 4)%.

CONCLUSIONS: After rectal administration of tramadol suppositories, absorption of the active ingredient was rapid, but its metabolism quickly transformed the parent drug to high levels of M2 and M5.

CLINICAL RELEVANCE: In the dog, rectal pharmaceutical formulation of tramadol would have a different pharmacokinetic behaviour than in humans.  相似文献   
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Abstract

AIM: To identify weather variables associated with the development of eggs of Teladorsagia (=Ostertagia) circumcincta, Trichostrongylus colubriformis and Haemonchus contortus to third-stage infective larvae (L3) under a range of climatic conditions on pasture in the North Island of New Zealand.

METHODS: Sheep faeces containing known numbers of eggs of all three nematode species were deposited on, or buried in, pasture plots at three sites, viz coastal Manawatu, Upper Hutt Valley, and East Cape hill country. Development was measured by recovering L3 from faeces, herbage and soil 28–31 days after deposition, on 13–18 occasions between January 2005 until July 2006. Weather data were recorded at each site, and the association between weather variables and number of L3 recovered was analysed using subsets regression to select best-fitting models from several candidate variables, after adjustment for efficiency of recovery of L3. A multiple linear regression model was then developed for each species, to select weather variables that had both significant and substantive effects on the number of L3 recovered.

RESULTS: For all species, mean daily temperature was the bestpredictor of the number of L3 recovered (p=0.001). For T.circumcincta the final model included mean daily temperature and soil temperature (R2=51%), and for T. colubriformis the model only included mean daily temperature (R2=55%). For development of H. contortus, mean daily temperature was the most significant variable, but moisture in the form of rainfall entropy, i.e. the temporal distribution of rainfall, overthe first 14 days was also significant in the final model (R2=34%).

CONCLUSIONS: Temperature was the most important determinant of developmental success of free-living nematodes on pasture at the study sites, and probably also for other parts ofNew Zealand with similar climates. Moisture was not significant in the development of T. circumcincta or T.colubriformis, implying that under the generally moist temperate climate in New Zealand, moisture is seldom limiting for development of these species. Haemonchus contortusappeared to be sensitive to moisture availability and precipitation in the first 14 days after deposition of faeces. The results of this study will be further developed as part of species-specific climate-driven models of parasite development in New Zealand.  相似文献   
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The current study examined the protective effects of l ‐glutamine and cytochalasin B during vitrification of immature bovine oocytes. Oocyte vitrification solution (PBS supplemented with 10% FCS, 25% EG, 25% DMSO and 0.5 m trehalose) was the vitrification control. Treatments were the addition of 7 μg/ml cytochalasin B, 80 mm glutamine or both cytochalasin and glutaminine for 30 s. After warming, oocytes were matured in vitro for 24 h, fixed and stained with Hoechst (33342) for nuclear maturation evaluation. l ‐glutamine improved the vitrified/warmed immature bovine oocytes viability (32.8%), increasing the nuclear maturation rates compared to other treatments and the no treatment vitrified control (17.4%). There was, however, no effect of cytochalasin B on in vitro maturation (14.4%).  相似文献   
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