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11.
为探究猪骨骼肌发育过程中免疫相关基因的表达模式以及相关生物学功能,本研究根据蓝塘猪和长白猪骨骼肌10个发育时期的转录组数据,对各时期免疫相关基因的表达数目和表达量进行分析,鉴定了相邻发育时期之间以及同一时期品种间差异表达的免疫相关基因,并对后者进行功能注释分析。结果表明:在蓝塘猪与长白猪骨骼肌发育过程中存在1 129个表达的免疫相关基因;胚胎期35 d和49 d、胚胎期91 d和生后期2d这2组相邻时期之间的差异表达免疫相关基因数目最多;品种间差异表达免疫相关基因数目则在胚胎期49d以及生后期180d最多,且趋向于在蓝塘猪上调表达,并富集在NIK/NF-κB信号传导、细胞凋亡的负调控等生物学过程中。本研究表明免疫相关基因在猪骨骼肌发育过程中存在表达,长白猪与蓝塘猪骨骼肌生长发育差异可能与NF-κB介导的细胞凋亡有关。  相似文献   
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Zinc (Zn) and copper (Cu) are strong inhibitors of bacterial biofilms in aqueous solutions, but are known toxins of crustaceans. A new metal application method; cold‐sprayed metal embedment, known to modulate metal release, was tested for its applications in crustacean larval culture systems. Cold‐spray technology allows metal particles to bond to plastics, while modulating metal ion release and biocide activity to the substrate boundary. In this study, Eastern spiny lobster (Sagmariasus verreauxi) larvae (phyllosoma) were cultured in the presence of cold‐sprayed Zn and Cu metal surfaces. Metal loss was monitored gravimetrically on embedded surfaces, assessment of water ion concentrations and analysis of phyllosoma body content were undertaken. Phyllosoma moulting, deformity and mortality patterns were monitored. Cold‐sprayed Zn‐ and Cu‐embedded surfaces were depleted with losses of 0.69% and 31.2% noted respectively. Culture water concentrations of these metals were elevated and accumulation by phyllosoma occurred. Water Zn concentrations of 18.5 μg L?1 were associated with chronic eyestalk moult deformities; the first report of Zn causing a non‐lethal moult deformity in crustacean larvae. The Cu surface lost a third of its metal mass with a water concentration of 40 μg L?1 causing acute toxicity and localization of composite granules in the midgut gland. Cu associated mortality was noted by Day 2 of culture with a LD 50 experienced by Day 9. Future work on the use of bioactive metals in aquaculture systems will focus on a range of different metal alloys, and improved modulation of ion release mechanisms through increased particle embedment depth and separation.  相似文献   
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A single screw technique is described as a temporary transphyseal bridge for the treatment of fetlock varus angular limb deformity in foals. This has been compared to tension band wiring with regards to rate of correction, cosmetic result and incidence of complications. The single screw was found to be an effective technique resulting in more rapid improvement of deviations in foals aged up to 5 months. Complications were minimal following both techniques and the final cosmetic result was better following single screw surgery.  相似文献   
15.
The aim of this study was to determine the prevalence of equine polysaccharide storage myopathy (EPSM) in two populations of horses in the UK. Biopsy specimens from 94 horses presented to an abattoir (population 1), and 46 horses with neuromuscular disorders presented to a university referral hospital (population 2) were obtained over a period of 4 years. Histological sections were examined by a veterinary pathologist for lesions including abnormal polysaccharide inclusions in myofibres.In population 1, a diagnosis of EPSM was made in 8% and non-specific myopathy in 33% of horses. In population 2, a diagnosis of EPSM was made in 22%, equine motor neurone disease (EMND) in 15% and non-specific myopathy in 37%. Within each population there was no difference in age, sex or breed distribution and muscle disease diagnosis. However, populations differed from each other in age and breed distributions and muscle disease diagnosis. EPSM was found in draft, Warmblood and related breeds and was diagnosed for the first time in cob-types. EMND was reported in 7/46 horses presented for neuromuscular disease and weakness, representing an important diagnosis in the UK. This study showed a high prevalence of EPSM and other myopathies in typical breeds of horses in the UK.  相似文献   
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Different levels of pressure were investigated to see if it was possible to induce triploidy at a lower pressure than previously used (600 bar) for Atlantic cod (Gadus morhua). Newly fertilized eggs were exposed to different levels of pressure: 400, 500, and 600 bar, and one control group (no pressure). Induction of triploidy occurred at each pressure level used in this experiment. Mean weight and length at the termination of the trial period was significantly lower, in the 400 bar group, compared to the other treatment groups. Microsatellite loci analysis revealed over 90% triploid outcome in each experimental group. Lower incidence of deformities was seen in the 400 bar group compared to the 500 and 600 bar groups. Overall this study demonstrated successful triploid induction at both low (400 bar) and medium (500 bar) pressures.  相似文献   
17.
Land-based aquaculture facilities often utilize additional bicarbonate sources such as commercial sea salts that are designed to boost alkalinity in order to buffer seawater against reductions in pH. Despite these preventative measures, many facilities are likely to face occasional reductions in pH and corresponding reductions in carbonate saturation states due to the accumulation of metabolic waste products. We investigated the impact of reduced carbonate saturation states (ΩCa, ΩAr) on embryonic developmental rates, larval developmental rates, and echinoplutei skeletal morphometrics in the common edible sea urchin Lytechinus variegatus under high alkalinity conditions. Commercial artificial seawater was bubbled with a mixture of air and CO2 gas to reduce the carbonate saturation state. Rates of embryonic and larval development were significantly delayed in both the low and extreme low carbonate saturation state groups relative to the control at a given time. Although symmetry of overall skeletal body lengths was not affected, allometric relationships were significantly different between treatment groups. Larvae reared under ambient conditions had significantly greater postoral arm and overall body lengths relative to body lengths than larvae grown under extreme low carbonate saturation state conditions, indicating that extreme changes in the carbonate system affected not only developmental rates but also larval skeletal shape. Reduced rates of embryonic development and delayed and altered larval skeletal growth are likely to negatively impact larval culturing of L. variegatus in land-based, intensive culture situations where calcite and aragonite saturation states are lowered by the accumulation of metabolic waste products.  相似文献   
18.
Urban trees are frequently exposed to unsuitable soil conditions that can hamper root system development, potentially affecting both tree health and stability. Engineered soil designs have been developed to increase soil volume for trees planted in confined spaces, and past research has shown that these designs improve growing conditions. However, tree stability in these engineered soils has received limited attention from researchers. In this study, we evaluated the stability of two tree species of contrasting soil quality tolerance (Prunus serrulata and Ulmus parvifolia) after 3 years growth in two skeletal soil mixes, in a suspended pavement design (uncompacted soil), and in a conventionally prepared soil pit. Tree stability was evaluated by measuring trunk resistance to a lateral deflecting force applied with a rope winch system under both ambient and near-saturated soil conditions. Although heavily irrigating the experimental soils had no effect on tree stability, species-specific responses to soil mixes were observed. P. serrulata grown in the gravel-based skeletal soil showed greater trunk deflection resistance than trees grown in the other soil treatments, yet the stability of U. parvifolia was unaffected by soil type. These species-specific responses were consistent with earlier observations of root development in which P. serrulata grew up to 60 times greater root length in gravel-based skeletal soil whereas U. parvifolia root growth was similar in all soil treatments. This research provides evidence that certain tree species planted in conventional tree pits may be more prone to uprooting due to poor root development and that root anchorage might be improved for these species by utilizing a skeletal soil mix.  相似文献   
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The extensive nature of this topic warrants this review paper to be divided into two parts: ‘Basic trimming in foals’ and ‘Therapeutic farriery in foals’. Management of the feet and limbs during this juvenile period will often dictate the success of the foal as a sales yearling or mature sound athlete. Overall hoof care in the foal is often a joint venture between the veterinarian and the farrier. The orthopaedic disorders discussed in this paper that require input from the two professions are flexural limb deformities (FLD) and angular limb deformities (ALD). The concept of protecting the foot from the deleterious effects of mal-loading created by many FLDs and ALDs is just as important as using the symptomatology as an instrument to correct the deformity. This paper presents a review of the current information regarding the farriery for these two limb deformities while dispelling some of the anecdotal methodology, such as the use of toe extensions to treat flexural deformities, that presently exists. Considering the deficiency of information in the literature, segments of this text will be based on the author's extensive clinical practice, comprehensive clinical records and comparisons of case outcomes.  相似文献   
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