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1.
H. Titmarsh A.G. Gow S. Kilpatrick J. Sinclair T. Hill E. Milne A. Philbey J. Berry I. Handel R.J. Mellanby 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2015,29(6):1473-1478
Background
Dogs with a chronic enteropathy (CE) have a lower vitamin D status, than do healthy dogs. Vitamin D status has been associated with a negative clinical outcome in humans with inflammatory bowel disease.Objectives
To examine the relationship between serum 25 hydroxyvitamin D (25(OH)D) concentrations at diagnosis and clinical outcome in dogs with a CE.Animals
Forty‐one dogs diagnosed with CE admitted to the Royal Dick School of Veterinary Studies, Hospital for Small Animals between 2007 and 2013.Methods
Retrospective review. Serum 25(OH)D concentrations were compared between dogs which were alive at follow up or had died because of non‐CE‐related reasons (survivors) and dogs which died or were euthanized due to their CE (non‐survivors). A binary logistic regression analysis was performed to determine significant predictors of death in dogs with CE.Results
Serum concentrations of 25(OH)D at the time a CE was diagnosed were significantly lower in nonsurvivors (n = 15) (median nonsurvivors 4.36 ng/mL, interquartile range 1.6–17.0 ng/mL), median survivors (n = 26) (24.9 ng/mL interquartile range 15.63–39.45 ng/mL, P < .001). Serum 25(OH)D concentration was a significant predictor of death in dogs with CE (odds ratio 1.08 [95% CI 1.02–1.18)]).Conclusions
Serum 25(OH)D concentrations at diagnosis are predictive of outcome in dogs with CE. The role of vitamin D in the initiation and outcome of chronic enteropathies in dogs is deserving of further study. 相似文献2.
Agreement of high definition oscillometry with direct arterial blood pressure measurement at different blood pressure ranges in horses under general anaesthesia 下载免费PDF全文
ObjectiveTo determine the agreement of high definition oscillometry (HDO) with direct arterial blood pressure measurements in normotensive, hypotensive and hypertensive horses during general anaesthesia.Study designExperimental study.AnimalsSeven healthy warmblood horses, aged 3–11 years, weighing 470–565 kg.MethodsMeasurements from a HDO device with the cuff placed around the base of the tail were compared with pressures measured invasively from the facial artery. High blood pressures were induced by intravenous (IV) administration of dobutamine (5 μg kg−1 minute−1) over ten minutes followed by norepinephrine (0.1 mg kg−1 IV) and low pressures by increasing the inspired fraction of isoflurane and administration of nitroglycerine (0.05 mg kg−1 IV). For analysis three pressure levels were determined: high (MAP>110 mmHg), normal (60 mmHg
3.
4.
The study investigated diversity and frequency of occurrence of glomale (Arbuscular- or Vesicular Arbuscular-) mycorrhizal
fungi on three farming systems in a drought prone and nitrogen deficiency site in southern Malawi. The farming systems comprised
of two agroforestry systems of Sesbania sesban (L) Merr intercropped with maize and Sesbania macrantha E Phillips & Hutch. intercropped with maize and a maize monocrop systems without fertilizer, with nitrogen, phosphorus and
a combination of nitrogen and phosphorus. Species diversity and species frequency of occurrence were examined in soil samples
obtained in the dry and wet seasons. Twelve glomale mycorrhizal species were recorded, four species being in the genus Acaulospora, four in Glomus, two in Gigaspora and two in Scutellospora. Species diversity in the two agroforestry systems were not significantly (p ≤ 0.05) different but had lower species diversity than maize monocrop with only Sesbania macrantha intercropped with maize significantly (p ≤ 0.05) lower. Species diversity was significantly increased by the inorganic nitrogen fertilizer. Inorganic phosphorus fertilizer
had no effect. The study shows that the occurrence and persistence of glomale species are influenced by agroforestry combinations,
and that the spores of most species are tolerant to dry conditions. Only four species responded to fertilizer application
with the occurrence of spores of some species high and some low. Management practices have great implication in the persistence
of spore propagules of glomale species.
The order Glomale was revised in 2001 and upgraded to a phylum Glomeromycota. 相似文献
5.
FLORES, the Forest Land Oriented Resource Envisioning System, is a framework to facilitate quantitative modelling of ecological,
economic and social issues at the landscape scale. This issue ofSmall-scale Forest Economics, Management and Policy describes the evolution of FLORES from a concept to a series of models calibrated for diverse locations, and documents the
lessons learned.
The idea to construct and use landscape-scale models of the forest frontier, based on simulating household decisions and land
use at a spatial scale close to the field level, arose from a desire to add rigour to land-use policy research at CIFOR, the
Center for International Forestry Research (Vanclay 1995). This simulation modelling approach to addressing interdisciplinary
issues, where people are strongly interacting with forest resources, became known as FLORES, the Forest Land Oriented Resource
Envisioning System (Vanclay 1998). Muetzelfeldtet al. (1998) constructed a simple prototype of a FLORES model to illustrate the concept and demonstrate the ability of a system-dynamics
modelling environment to animate such a model (Muetzelfeldt and Taylor 1997, 2001, Muetzelfeldt and Massheder 2003). In 1999,
FLORES became a reality, when 50 scientists from diverse disciplines met in Bukittinggi, Indonesia to construct the first
FLORES model styled on this prototype (CIFOR 1999, Vanclayet al. 2003).
The research reported in this special issue was made possible by generous financial support from the Department for International
Development (UK), the European Community, the Asian Development Bank (under RETA 5812) and the Center for International Forestry
Research. The views expressed herein are those of the authors alone. We would like to thank the following people who have
assisted in the production of this special issue by acting as anonymous referees for these and other papers: Andy Warner,
Brendan Moran, Bruno Verbist, Chris Dake, Chris Legg, Doug Sheil, Euan Mason, Francois Bousquet, Frank Vanclay, Geoff Slaughter,
James Gambiza, John Herbohn, John Poulsen, Jungho Suh, Mike Spilsbury, Paul Phillips, Paul van Gardingen, Phil Norman, Philip
Nyhus, Roger Wheate, Ross Sigley, Steve Harrison and Tom Evans. Thanks also to the editorial staff, especially Steve Harrison,
John Herbohn and Jungho Suh, for making this special issue possible. 相似文献
6.
7.
Norton E. Atkins Claire Cianchi S. M. Rutter Sarah J. Williams Carrie Gauld Gemma L. Charlton Liam A. Sinclair 《Grass and Forage Science》2020,75(2):181-191
The effects of a limited grazing period on the performance, behaviour and milk composition of high-yielding dairy cows were examined. A total of 56 Holstein cows yielding 44.7 ± 0.42 kg/day were allocated to one of four treatments in one of two, 4-week periods. Treatments were as follows: control (C)—cows housed and offered TMR ad libitum; early grazing (EG)—cows grazed for 6 hr after morning milking then housed; delayed grazing (DG)—cows returned to housing for 1 hr after morning milking followed by grazing for 6 hr, then housed; restricted TMR (RT)—cows grazed for 6 hr after morning milking, then housed and fed TMR at 75% of ad libitum. Intake of TMR was highest in cows receiving C, intermediate in EG and DG, and lowest in RT at 26.9, 23.6, 24.7 and 20.3 kg DM/day respectively. Pasture intake was similar in cows receiving EG or DG, but was higher in RT at 2.4, 2.0 and 3.5 kg DM/day respectively. Milk yield was similar between cows receiving C, EG or DG, but lowest in RT at 45.7, 44.2, 44.9 and 41.7 kg/cow, respectively, while milk fat content of C18:3 n-3 was increased by grazing. Cows in C spent more than 55 min/day longer lying and had three additional lying bouts/day, while lying bouts were shorter than for cows receiving EG, RT or DG. It is concluded that high-yielding cows can be grazed for 6 hr/day with little impact on performance, provided TMR is available ad libitum when housed. 相似文献
8.
Katja Kehlenbeck Roeland Kindt Fergus L. Sinclair Anthony J. Simons Ramni Jamnadass 《Agroforestry Systems》2011,83(2):133-147
Agroforestry systems are potentially suitable for conservation of tree genetic resources. Farmers around Mt. Kenya usually
integrate trees into their farm. Large parts of these trees seem to be of exotic origin, whereas indigenous species have priority
for conservation. This study aimed at determining on-farm richness, composition and frequency of indigenous and exotic woody
species around Mount Kenya to assess the suitability of farms for the conservation of indigenous tree species. 265 on-farm
plots of 0.5 ha size each were selected in 18 different agro-ecological zones by using a stratified sampling scheme. All woody
species within the plot were recorded with their local and scientific names. Total species richness was 424 (including 306
indigenous ones), mean richness per plot 16.5 species (including 8.8 indigenous ones). Eight out of the 10 most frequent species
were exotic ones with Grevillea robusta from Australia ranking first (found on almost 76% of the surveyed farms). The proportion of indigenous species increased
with increasing aridity and temperature. Dominance of exotic species was found at farms of humid mid- and highlands. Ordination
analysis revealed that mostly exotic species contributed to separation of farms in the highlands and upper midlands, whereas
indigenous species in the lower midlands and lowlands. As the frequencies of most indigenous trees were low, only parts of
the surveyed farms can contribute to conservation of tree genetic resources, particularly the less intensively managed farms
of the more arid lands. Farmers’ access to knowledge on valuable indigenous tree species and to quality seedlings of these
trees need to be improved to increase indigenous species’ frequencies on farms and possibly to replace some of the exotic
species in the future. 相似文献
9.
Uptake of veterinary medicines from soils into plants 总被引:17,自引:0,他引:17
Boxall AB Johnson P Smith EJ Sinclair CJ Stutt E Levy LS 《Journal of agricultural and food chemistry》2006,54(6):2288-2297
Medicines play an important role in the treatment and prevention of disease. Whereas the side effects on human and animal health resulting directly from treatment have been widely documented, only recently have the occurrence and fate of medicines in the environment and the potential consequences for human health been recognized as an issue warranting consideration. Medicines have been shown to be released to soils and to persist in the environment. This study was performed to investigate the potential for a range of veterinary medicines to be taken up from soil by plants used for human consumption and to assess the potential significance of this exposure route in terms of human health. Soil analyses indicated that, for selected substances, measurable residues of these are likely to occur in soils for at least 5 months following application of manure containing these compounds. Experimental studies on the uptake of veterinary medicines into carrot roots (tubers) and lettuce leaves showed that only florfenicol, levamisole, and trimethoprim were taken up by lettuces, whereas diazinon, enrofloxacin, florfenicol, and trimethoprim were detected in carrot roots. Measured concentrations in plant material were used to model potential adult human exposure to these compounds. Although exposure concentrations were appreciable in a few instances, accounting for approximately 10% of the acceptable daily intake values (ADI), all were lower than the ADI values, indicating that, at least for compounds with properties similar to those considered here, there is little evidence of an appreciable risk. This exposure route may, however, be important when veterinary medicines have a very low ADI, at which they elicit subtle effects over prolonged periods, or when exposure is occurring via a number of routes at once. Although degradation products (produced in the soil or the plant) were not measured, it is possible for some substances that these could increase the risks to consumers. 相似文献
10.
The lipid content and fatty acid composition in the edible meat of twenty-nine species of wild and cultured freshwater and marine fish and shrimps were investigated. Both the lipid content and fatty acid composition of the species were specified due to their unique food habits and trophic levels. Most of the marine fish demonstrated higher lipid content than the freshwater fish, whereas shrimps had the lowest lipid content. All the marine fish and shrimps had much higher total n-3 PUFA than n-6 PUFA, while most of the freshwater fish and shrimps demonstrated much lower total n-3 PUFA than n-6 PUFA. This may be the biggest difference in fatty acid composition between marine and freshwater species. The cultured freshwater fish demonstrated higher percentages of total PUFA, total n-3 PUFA, and EPA + DHA than the wild freshwater fish. Two freshwater fish, including bighead carp and silver carp, are comparable to the marine fish as sources of n-3 PUFA. 相似文献