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21.
Objective To report the rapid transmission of bovine ephemeral fever ( BEF) virus from north-western New South Wales south to the Victorian border in January 2008 and to present data that suggests an uncommon meteorological event caused this rapid southward dispersal of vectors. Procedure The locations of reported clinical cases, data from sentinel herds and results from a survey of cattle in the southern affected area were examined to delineate the distribution of virus transmission. Synoptic weather charts for January 2008 were examined for meteorological conditions that may have favoured movement of vectors in a southerly direction. Results Cases of BEF and exposure to BEF virus in NSW were confirmed west of the Great Dividing Range, extending from the Queensland border to Finley, on the far North Coast and around the Hunter Valley. A low-pressure system moved south across the state on 18–19 January 2008, preceding the first cases of BEF in the south of NSW by 1–2 days. Conclusion Heavy rainfall in December 2007 provided a suitable environment for vector breeding, resulting in the initiation of and support for continuing BEF virus transmission in north-western NSW. The movement of a low-pressure system south across central western NSW in mid-January 2008 after the commencement of BEF virus transmission in the north-west of the state provided a vehicle for rapid southward movement of infected vectors.  相似文献   
22.
SUMMARY The need for dietary management of renal senescence and the beginning of chronic renal failure should be evaluated in all middle-aged dogs. One survey found that 35% were overweight and 10% underweight; another that 25% were mildly azotaemic, with 5% showing slight clinical signs of chronic renal failure. Dogs in prime condition or overweight are candidates for a diet low in energy (for example 3.0–3.3 kcal/g dry matter, DM), but thin dogs need a higher caloric density (such as 4.0–4.5 kcal/g DM). Healthy older dogs need higher dietary protein than the minimum for maintenance (about 20% on a metabolisable energy basis, ME) of young mature dogs. Thin older dogs showing signs of renal insufficiency may benefit from moderate protein and near-minimal phosphorus in the diet. In dogs with chronic renal failure, clinical, haematological and biochemical responses to the combination of low protein (13–16% ME) and low phosphorus (0.4% DM) were positive in one clinical trial but not in three others. Only beneficial responses, such as less proteinuria, less renal impairment and lower mortality, have been reported for diets containing low phosphorus and moderate protein (20–31% ME). Individual dietary goals for energy, protein and phosphorus should be chosen for each middle-aged or older dog; these goals may be met by a single product or mixtures of products.  相似文献   
23.
The formation of a Bose-Einstein condensate of a dilute atomic gas has been studied in situ with a nondestructive, time-resolved imaging technique. Sodium atoms were evaporatively cooled close to the onset of Bose-Einstein condensation and then suddenly quenched to below the transition temperature. The subsequent equilibration and condensate formation showed a slow onset distinctly different from simple relaxation. This behavior provided evidence for the process of bosonic stimulation, or coherent matter-wave amplification, crucial to the concept of an atom laser.  相似文献   
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The main objective of the present work was to study the effect of cryopreservation of European eel sperm both on the sperm viability and the spermatozoa head morphology. Spermatozoa morphology was evaluated with computer-assisted morphology analysis after collection in fresh samples, after adding the freezing medium containing dimethyl sulfoxide as cryoprotectant and, finally, after the cryopreservation process and thawing. Cell viability was assessed, in both fresh and thawed samples, by Hoechst 33258 staining. Computer-assisted sperm analysis (CASA) was used to determine the percentage of motile cells and to measure motility parameters in sperm samples. A significant decrease of head perimeter (12.56%) and area (17.90%) was detected from spermatozoa in fresh to thawed samples, indicating that cells do not recover the original size after the cryopreservation process. CASA was used to measure the percentage of motile cells (51.9%) and spermatozoa motility parameters such as curvilinear, straight line and angular path velocities, as well as beating cross frequency. This technique was employed in the fresh sperm samples but proteins present at the freezing medium (L-alpha-phosphatidylcholine) made impossible to use this last technique in thawed samples. When sperm viability was assessed by Hoechst staining, a significant decrease of approximately 15% (73.10 vs 58.26%) of alive spermatozoa was registered from fresh to thawed samples. The percentage of motile cells measured by CASA in fresh samples (51.9%) was lower than the percentage of alive cells determined by Hoechst stainning, suggesting the existence of different batches of spermatozoa in different stages of development, even during the eight to tenth weeks of treatment, when the highest sperm quality was found.  相似文献   
26.
A feeding trial using various levels of dry pods of ghaf (Prosopis cineraria) was carried out with 28 Omani native male sheep. Individual feed intake and body weight were determined for 50 days to allow assessment of the effects of the feeds on growth, feed intake, feed conversion and carcase measurements. The ripened ghaf pods contained 91% dry matter (DM), 13.5% crude protein (CP), 14.3% crude fibre (CF), 1.3% ether extract (EE) and 5.2% ash (on DM basis). Four levels of ghaf (0, 15%, 30% and 45%) were used with corresponding decreasing proportions of Rhodes grass (RGH) hay. Animals fed rations containing RGH as the sole source of roughage and no ghaf grew faster (135 g/day) and had better feed conversion than those fed various levels of ghaf. Sheep fed 15% ghaf gained reasonably well (90 g/day) and had carcase attributes similar to those fed no ghaf. Sheep fed 30% ghaf still gained weight but those fed 45% ghaf lost weight. Negative effects on growth appeared to occur after 6 weeks of feeding ghaf.  相似文献   
27.
The precise determination of the embryonic chronology is very important in reproductive biotechnologies, especially in estimating embryonic age. Thus, there is a need for greater knowledge and standardization for determining the chronology of embryonic development and functional morphology. We describe aspects of embryonic development in two domestic carnivores to add knowledge about organ peculiarities and for application in veterinary practice, in prenatal development and in the biotechnology fields. We found that the development of differential characteristics of embryonic organs occurs in the first trimester of pregnancy for both species. Thus, using the combination of the crown‐rump length, macroscopic analysis and optical microscopy, it is possible to predict gestational age more precisely in animals that lack a defined breed and establish an embryonic pattern.  相似文献   
28.
Parthenote embryos are being considered as an alternative source of embryonic stem cells. However, as there is still a dearth of knowledge of this kind of embryos, a better understanding of their biology is needed for their application. In this work, we studied the differences and similarities between parthenotes and normal embryos at the blastocyst stage in vivo developed. We analysed the expression of factor OCT‐4, vascular endothelial growth factor (VEGF), insulin‐like growth factor I (IGF‐I) and uteroglobin (UG) by real‐time PCR. To do so, oocytes were recovered and after activation procedure were transferred by ventral middle laparoscopy to receptive does to undergo completely in vivo development. Does were slaughtered 6 days post‐ovulation induction, and parthenote and normal embryos were recovered for mRNA expression analysis. Our results reported that parthenotes and normal embryos showed similar mRNA expression for OCT‐4 and VEGF. However, IGF‐I and UG showed to be over‐expressed in parthenote embryos. Thus, our study highlights that despite the in vivo development of parthenotes, they still seem to have an altered expression and, therefore, to be different to normal embryos. The altered expression pattern of parthenote embryos suggests that these embryos should be studied carefully before future application.  相似文献   
29.
This study was carried out to evaluate the effect of platelet-rich plasma (PRP) on the treatment of tendinopathy induced in the superficial digital flexor tendon (TFDS) of horses, by using histologic evaluation. Six healthy crossbred geldings aged 8 to 15 years (12 ± 3) were used. The TFDS tendinopathy was provoked in both forelimbs, by intratendinous administration of 2.5 mg collagenase (2.5 mg/mL), and this procedure was considered as the beginning of the experimental phase. At 12 days after induction of the tendinopathy, the animals were subjected to the following treatments: (1) in the lesion caused in the right superficial digital flexor tendon (PRP-treated group), 2.5 mL PRP activated with calcium chloride at 0.0125 mol/L at concentrations from 320,000 to 500,000 platelets/μL, were injected; (2) in the tendinopathy of the left SDFT (control group), 2.5 mL 0.9% saline solution was administrated. Thirty-six days after the treatments, a biopsy of the injured area was performed for histologic evaluation. In both groups, the histologic analysis showed an increase in the fibroblastic density, as well as the presence of neovascularization, lymphocytes, and plasmocytes infiltrate and tissue organization at variable intensity. In the PRP-treated group, the SDFT was more organized, with the collagen fibers and fibroblasts being better arranged on the tendon matrix. The numbers of the fibroblasts and blood vessels did not differ between the groups. Histologic evaluation 36 days after tendinopathy showed that injuries under a single PRP treatment present a more uniform and organized tissue repair when compared with the control group.  相似文献   
30.
Lack of a 19th-century baseline temperature against which 20th-century warming can be referenced constitutes a deficiency in understanding recent climate change. Combination of borehole temperature profiles, which contain a memory of surface temperature changes in previous centuries, with the meteorological archive of surface air temperatures can provide a 19th-century baseline temperature tied to the current observational record. A test case in Utah, where boreholes are interspersed with meteorological stations belonging to the Historical Climatological Network, yields a noise reduction in estimates of 20th-century warming and a baseline temperature that is 0.6° ± 0.1°C below the 1951 to 1970 mean temperature for the region.  相似文献   
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