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111.
Nadine Idalan Louise F. Martin Marcus Clauss 《Journal of animal physiology and animal nutrition》2019,103(4):1015-1022
Changes in digesta dry matter (DM) and mean digesta particle size (MPS) along the gastrointestinal tract are well known in ruminants, but not in camelids. We collected digesta from the dorsal (d) and ventral (v) first forestomach compartment (C1), the second forestomach compartment (C2), three proximal segments and the subsequent glandular part of the third compartment (C3A‐D), the caecum and the faeces twelve llamas (Lama glama). DM analysis indicates the presence of digesta stratification in the C1, the presence of fluid in the C2 to facilitate the sorting function of this compartment, the fluid‐absorbing function of the proximal parts of the C3, the secretion of enzymes and digestive acids in the C3D, and the water‐resorbing function of the lower intestinal tract. These findings illustrate the functional resemblance between the gastrointestinal tract of camelids and cattle‐like ruminants (C1 equivalent to the rumen with stratified contents, C2 to the reticulum, C3A/B/C to the omasum and C3D to the abomasum). MPS analysis revealed a progressive reduction in MPS from the C1 to the distal C3. This gradual transition is different from the clear‐cut threshold in ruminants between the reticulum and the omasum and had so far only been described in dromedaries (Camelus dromedarius). These findings indicate that regardless of the convergent property of rumination and resemblance of general mechanisms involved in contents stratification and particle sorting, differences between ruminants and camelids exist that could be interpreted as a more efficient functionality of the ruminant forestomach. 相似文献
112.
C.B. Magnusson K.P. Poulsen J.A. Budde F.A. Hartmann N.A. Aulik S.M. Raabis A.S.D. Moreira B.J. Darien S.F. Peek 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2018,32(1):469-473
Background
Periodic lack of availability and high cost of commercially produced isotonic fluids for intravenous (IV) use in horses have increasingly led to use of home‐made or commercially compound fluids by veterinarians. Data regarding the quality control and safety of compounded fluids would be of benefit to equine veterinarians.Objectives
To compare electrolyte concentrations, sterility, and endotoxin contamination of commercially available fluids to 2 forms of compounded isotonic crystalloid fluids intended for IV use in horses.Methods
Prospective study. Two methods of preparing compounded crystalloids formulated to replicate commercial Plasma‐Lyte A (Abbott, Chicago, IL) were compared. One formulation was prepared by a hand‐mixed method involving chlorinated drinking water commonly employed by equine practitioners, and the other was prepared by means of ingredients obtained from a commercial compounding pharmacy. The variables for comparison were electrolyte concentrations, sterility, and presence of endotoxin contamination.Results
Electrolyte concentrations were consistent within each product but different between types of fluids (P < 0.0001). Hand‐mixed fluids had significantly more bacterial contamination compared to commercial Plasma‐Lyte A (P = 0.0014). One of the hand‐mixed fluid samples had detectable endotoxin contamination.Conclusions and Clinical Importance
Chlorinated drinking water is not an acceptable source of water to compound isotonic fluids for IV administration. Equine practitioners should be aware of this risk and obtain the informed consent of their clients. 相似文献113.
114.
115.
James N. Nutt Louise L. Southwood Yvonne A. Elce David M. Nunamaker 《Veterinary surgery : VS》2010,39(5):594-600
Objective: To compare the mechanical properties and failure modes of a standardized short oblique distal radial metaphyseal osteotomy stabilized using either a transfixation pin cast (TPC), a modular‐sidebar external skeletal fixator (ESF), or a solid‐sidebar ESF (modular‐ or solid‐ESF, respectively) using static or cyclic axial loading to failure. Study Design: In vitro study. Animals: Equine cadaver forelimbs. Methods: A 30° oblique distal radial osteotomy was created and stabilized using 1 of the 3 fixation methods: (1) TPC, (2) modular‐ESF, or (3) solid‐ESF. Limbs were tested using static (TPC, modular‐ESF, and solid‐ESF) or cyclic (TPC and solid‐ESF) axial loading to failure. The stiffness, yield load, yield displacement, failure load, and failure displacement for static loading and the cycles to failure for cyclic loading at 75% failure load were obtained. Data were analyzed using a Kruskal–Wallis test. Level of significance was P<.05. Results: The solid‐ESF had a greater stiffness, higher yield and failure load and a lower yield and failure displacement than the TPC (P=.01) and the modular‐ESF (P=.02). TPC had a higher yield load, failure load, and yield displacement than the modular‐ESF (P=.01). Mean cycles to failure for TPC was 2996±657 at a load of 16,000 N and for solid‐ESF 6560±90 cycles at a load of 25,000 N. Conclusions: The solid‐ESF was stiffer and stronger than the TPC and modular‐ESF and failed at a greater number of cycles in axial loading compared with the TPC. Clinical Relevance: This study is an initial step in evaluating the solid‐ESF. Further testing needs to be performed, but this fixation may offer a viable alternative to the traditional TPC for stabilization of long bone fractures in adult horses. 相似文献
116.
Jacob Nabe-Nielsen Willy Severiche Todd Fredericksen Louise Imer Nabe-Nielsen 《New Forests》2007,34(1):31-40
Sustainable management of selectively logged tropical forests requires that felled trees are replaced through increased recruitment
and growth. This study compares road track and roadside regeneration with regeneration in unlogged and selectively logged
humid tropical forest in north-eastern Bolivia. Some species benefited from increased light intensities on abandoned logging
roads. Others benefited from low densities of competing vegetation on roads with compacted soils. This was the case for the
small-seeded species Ficus boliviana C.C. Berg and Terminalia oblonga (Ruiz & Pav.) Steud. Some species, e.g. Hura crepitans L., displayed patchy regeneration coinciding with the presence of adult trees. Our results suggest that current management
practices could be improved by intensifying logging in some areas to improve regeneration of light demanding species. Sufficient
seed input in logged areas should be ensured by interspersing large patches of unlogged forest with logged areas. This may
also assist regeneration of species that perform poorly in disturbed areas. 相似文献
117.
Louise H. Robinson Juan Juttner Andrew Milligan Jelle Lahnstein Jason K. Eglinton David E. Evans 《Journal of Cereal Science》2007,45(3):343-352
Previous pilot brewing trials have demonstrated that in the absence of a molecular weight (MW) 12,000 (barley silica eluate (SE) protein), the beer brewed from the malt of these SE −ve varieties formed less haze after accelerated ageing than beers brewed using SE +ve malt varieties. The previously described SE protein was characterised using comparative two-dimensional (2-D) gel electrophoresis immunoblots of barley seed extracts from both SE +ve and SE −ve varieties. The SE protein spot identified was excised and its partial sequence determined, after in-gel cleavage using trypsin and separation of the resulting fragments by reversed-phase high performance liquid chromatography (HPLC). N-terminal sequence analysis of the tryptic peptides from SE +ve and SE −ve varieties identified the SE protein as the barley trypsin inhibitor-CMe precursor (BTI-CMe). The mature BTI-CMe protein is 13.3 kDa and its functional gene is located on chromosome 3H. Cloning of the BTI-CMe protein demonstrated that both SE −ve and SE +ve barley varieties contain a BTI-CMe protein family member that is similar but has a consistently different sequence, primarily in the last 30 amino acid residues of their C-termini. 相似文献
118.
The identification of a barley haze active protein that influences beer haze stability: The genetic basis of a barley malt haze active protein 总被引:2,自引:0,他引:2
Louise H. Robinson Peter Healy Doug C. Stewart Jason K. Eglinton Chris M. Ford David E. Evans 《Journal of Cereal Science》2007,45(3):335-342
In bright beers, the formation of haze is a serious quality problem, which places limitations on the storage life of the product. Sodium dodecyl sulphate polyacrylamide gel electrophoresis (SDS-PAGE) immunoblot analysis using an antiserum that was raised against a silica eluate (SE) protein fraction (obtained from silica gel, used for the colloidal stabilisation of beer), detected a range of protein bands in barley, malt, beer and haze. A polymorphism was observed in which some barley varieties contained a molecular weight (MW) 12,000 band (SE +ve) while in other varieties this band was absent (SE −ve). A survey of 219 Australian and international barley varieties, including a comprehensive selection of current and past malting varieties, identified 181 varieties as SE +ve, and 38 varieties as SE −ve. Previous pilot brewing trials demonstrated that SE −ve varieties are desirable as the beer brewed from the malt of these varieties formed less haze after accelerated ageing than beers brewed using SE +ve malt varieties. The genetic basis for the absence of the SE protein was conferred by a recessive allele at a single locus. Interval mapping analysis showed that the MW 12,000 band mapped to the short arm of chromosome 3H. 相似文献
119.
Veeriah S Hofmann T Glei M Dietrich H Will F Schreier P Knaup B Pool-Zobel BL 《Journal of agricultural and food chemistry》2007,55(8):2892-2900
Colorectal tumor risks could be reduced by polyphenol-rich diets that inhibit cell growth. Here, apple polyphenols were studied for effects on the survival of colon adenoma (LT97) and carcinoma-derived (HT29) cell lines. Three apple extracts (AEs) from harvest years 2002-2004 were isolated (AE02, AE03, and AE04) and fermented in vitro with human fecal flora. Extracts and fermentation products were analyzed for polyphenols with HPLC. The cells were treated with AEs (0-850 microg/mL) or fermented AEs (F-AEs, 0-9%), and survival was measured by DNA staining. All AEs contained high amounts of polyphenols (311-534 mg/g) and reduced cell survival (in LT97 > HT29). AE03 was most potent, possibly because it contained more quercetin compounds. Fermentation of AEs resulted in an increase of short chain fatty acids, and polyphenols were degraded. The F-AEs were approximately 3-fold less bioactive than the corresponding AEs, pointing to a loss of chemoprotective properties through fermentation. 相似文献
120.
Host-virus interactions play an important role for the clinical outcome of classical swine fever virus (CSFV) infections in pigs. Strain virulence, host characteristics and environment are all factors that markedly influence disease severity. We tested CSFV strains of varying virulence in an experimental set-up, reducing the influence of host and environmental factors. Thus, weaner pigs were inoculated with one of 4 CSFV strains in order to compare the pathogenesis for a 3-week-period after infection. CSFV strains selected were 2 new and 2 previously characterized. None of these strains had been tested in Danish outbred pigs before. Clinical observations grouped the infected pigs into two different categories reflecting either non-specific, mainly gastro-intestinal, problems, or severe disease including high fever within the first week after inoculation. Gross-pathological findings varied between strains, however, lymphoid atrophy and growth retardation represented a consistent finding for all 4 strains. Virus distribution, viral load and in particular virus persistence differed, but supported present practice that recommends lymphoid tissue, most optimal tonsil and lymph nodes, as target material to be applied for early laboratory diagnosis. The present study demonstrated constraints associated with early detection of infections with CSFV strains of low virulence. Since neither clinical symptoms nor pathological lesions observed with these strains constituted characteristic signs of CSF, the risk of neglecting a CSF suspicion is immediate. Therefore, topical information on new outbreaks and continuous enhancement of an efficient surveillance system is of great importance to prevent further spread of CSF within the pig population. 相似文献