Growth in three Karoo shrub species under various grazing treatments: the tracking of marked individuals over 25 years     

Helga van der Merwe  Suzanne J Milton 《African Journal of Range and Forage Science》2019,36(1):61-66

Growth studies of long-lived shrubs are uncommon. In semi-arid rangelands, livestock and wildlife grazing influence growth processes and may interact with changing climate. Tierberg-LTER, excluded from livestock since 1987, and two adjacent ranches allowed for a comparative growth study of three shrub species (Osteospermum sinuatum – palatable, Pteronia empetrifolia – moderately palatable, and P. pallens – unpalatable) across contrasting present ungulate herbivory (none in exclosures, wildlife only, or livestock and wildlife combined) and past livestock herbivory (moderate and overgrazed). Marked individuals were measured at irregular intervals over 25 years. Stem basal diameter (mm), height (m) and two canopy diameters (m) were measured at the onset of the study and in 2014. Mean basal diameter growth (mm y^?1) varied between species and treatments. Change in mean attribute values was influenced by interactions with grazing history and treatments. Some historical and grazing treatments had a negative effect on the palatable O. sinuatum and no significant effect on moderately palatable P. empetrifolia or unpalatable P. pallens. The age of the originally marked individuals are unknown but >70% of these individuals survived over the 25-year period. Our results support previous findings that dwarf shrubs in deserts are slow growing and long lived, and that grazing regime affects plant growth.  相似文献   

Comparison of the performance of the IDEXX SediVue Dx® with manual microscopy for the detection of cells and 2 crystal types in canine and feline urine     

Annalisa M. Hernandez  Graham E. A. Bilbrough  Dennis B. DeNicola  Celine Myrick  Suzanne Edwards  Jeremy M. Hammond  Alex N. Myers  Johanna C. Heseltine  Karen Russell  Marco Giraldi  Mary B. Nabity 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2019,33(1):167-177

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Homemade diets: attributes, pitfalls, and a call for action     

Remillard RL 《Topics in companion animal medicine》2008,23(3):137-142

At one time, it was estimated that the majority of dogs and cats in the United States received 90% or more of their nutrition from complete and balanced commercially prepared foods, and this estimate was reaffirmed in a 2004 survey. However, 4 years and several pet food and treat recalls later, fewer pet owners are feeding commercial pet food products exclusively and more are asking questions and looking for alternatives. As in any market-driven economy, there are many more alternative diets and food products available today from which pet owners may select. A difficult to measure but growing number of clients are feeding homemade diets that provide 100% of their pet's nutrition, while a larger number are feeding a combination of products, treats, and home prepared meals. Most practitioners can attest to this increase in their client's interest in homemade meals and to having insufficient knowledge to assist them. At a time when motivated clients are considering homemade for their pets as an alternative, veterinarians are less than adequately versed in canine and feline nutrition and dietary options. The article addresses the two most important health issues concerning pet owners and veterinarians about homemade diets: nutritional integrity and food safety.  相似文献   

Comparison of a computed tomographic pulmonary trunk to aorta diameter ratio with echocardiographic indices of pulmonary hypertension in dogs          下载免费PDF全文

James Sutherland‐Smith  Elyshia J. Hankin  Suzanne M. Cunningham  Amy F. Sato  Bruce A. Barton 《Veterinary radiology & ultrasound》2018,59(1):18-26

There are limited criteria for the detection of pulmonary hypertension in dogs undergoing computed tomography (CT) for pulmonary disease. This retrospective analytical exploratory study compared a CT pulmonary trunk to aorta ratio with echocardiographic estimates of pulmonary hypertension. Dogs having both a contrast thoracic CT and echocardiogram were selected and maximal pulmonary trunk and descending aorta diameters were measured by two observers on a single transverse CT image. Computed tomographic diameter ratios were compared with the echocardiographic parameters of tricuspid regurgitation gradient, right ventricular acceleration time‐to‐ejection time ratio, pulmonary insufficiency gradient, and pulmonary artery to aorta diameter. A total of 78 dogs were sampled, with 44 dogs having one or more finding suggestive of pulmonary hypertension. A moderate positive correlation was shown between tricuspid regurgitation gradient and CT pulmonary trunk to aorta ratio (r = 0.61, P‐value < 0.0001). Mean CT pulmonary trunk to aorta ratio of dogs with moderate (P = 0.0132) and severe (P < 0.0003) pulmonary hypertension were significantly higher than normal dogs. There was no significant difference in mean CT pulmonary trunk to aorta ratio between normal and mild pulmonary hypertension dogs (P = 0.4244). The intraclass correlation coefficient (0.72) showed good reproducibility of the ratio. Findings indicated that CT pulmonary trunk to aorta ratio is a reproducible and potentially useful method to predict moderate and severe pulmonary hypertension in dogs, but not mild pulmonary hypertension. In dogs undergoing thoracic CT for pulmonary disease, an increased ratio should prompt follow up echocardiography.  相似文献   

Correction to: Vulnerability of coffee (Coffea spp.) genetic resources in the United States     

Krishnan  Sarada  Matsumoto  Tracie  Nagai  Chifumi  Falconer  James  Shriner  Suzanne  Long  Jennifer  Medrano  Juan F.  Vega  Fernando E. 《Genetic Resources and Crop Evolution》2021,68(7):2711-2711

Genetic Resources and Crop Evolution - The correct article title is provided here, Vulnerability of coffee (Coffea spp.) genetic resources in the United States.  相似文献   

Water,salt and nutrient fluxes of tropical tidal salt flats   总被引：2，自引：0，他引：2  

Ridd  Peter  Sam  Renagi  Hollins  Suzanne  Brunskill  Gregg 《Mangroves and Salt Marshes》1997,1(4):229-238

The water budget of a tropical tidal salt flat in dry tropical Australia has been studied with particular emphasis on estimating the groundwater fluxes. Salt was used as a passive tracer to determine some of these fluxes. Groundwater salt accumulation (or loss) was less than 1 kg/m³/month. Surface water leaving the flat at a higher salt concentration than flood water causes a net outwelling of salt of between 0.4 and 1 kg/m²/month. Evaporation from the salt flat was estimated to be 70 mm/month. Using these measurements and a simple model of the groundwater flows, it is concluded that the groundwater loss is less than 40 mm/month. The accuracy of the salt budget was insufficient to rule out the possibility that the net groundwater motion was upwards. Measurements of Si and PO_{_4} fluxes indicated that the net outwelling due to surface water flows were respectively 3 mmole/m²/month and 0.014 mmole/m²/month. A net groundwater loss of 10 mm would produce a similar magnitude outwelling due to groundwater discharge. The mangrove-fringed tropical tidal salt flats are the source of large quantities of nutrients that are released to the near-shore zone.  相似文献   

Innovation Processes in Forest-related Recreation Services: The Role of Public and Private Resources in Different Institutional Backgrounds     

Gerhard Weiss  Suzanne Martin  Anne Matilainen  Birger Vennesland  Carmen Nastase  Erlend Nybakk  Laura Bouriaud 《Small-Scale Forestry》2007,6(4):423-442

This article examines innovation processes in forest recreational services on the basis of case studies in five European countries with differing institutional backgrounds of forest ownership and access rights. The analysis reveals that forest-related recreation services are developed under varying institutional conditions and on public as well as private land. Ideas for innovations in recreational services may come from within but often outside the forestry sector. Financing is provided from public and private sources. Both public and private spheres have important roles in providing natural, human and financial resources and usually a network of public and private actors are involved in innovation processes. Of particular importance are cross-sectoral interactions between forestry and tourism. Greater institutional support is needed for the development of forest-related recreation services because the field is at an early stage of development. It is concluded that support should focus on providing ideas and financial resources for product development and on facilitating cross-sectoral interaction between forestry and tourism actors. A particular need is seen for development of models for durable interaction between land owners and tourism operators on a regional scale.  相似文献   

Sorghum bran in the diet dose dependently increased the excretion of catechins and microbial-derived phenolic acids in female rats     

Gu L  House SE  Rooney L  Prior RL 《Journal of agricultural and food chemistry》2007,55(13):5326-5334

Sorghum bran is concentrated with procyanidins (predominately polymers), which may be beneficial for health in humans; however, the bioavailability of procyanidins is not well-understood. Female Sprague-Dawley rats were fed an AIN93G diet containing 0, 5, 10, 20, or 40% Hi-tannin sorghum bran (n = 5-7 for each group) for 50 days. Sorghum bran contained 23.3 mg/g of procyanidins. The urinary excretions of catechin, epicatechin, methylated catechins, and phenolic acids were analyzed using liquid chromatography-tandem mass spectrometry. Sorghum bran dose dependently increased the urinary excretion of catechin (0-2.2 nmol/day) and 3'-O-methylcatechin (0-9.5 nmol/day). Their serum concentrations also increased with dose (range of 0-14 nM for 3'-O-methylcatechin). Among the 14 phenolic acids analyzed, 3,4-dihydroxybenzoic acid, 3-methoxy-4-hydroxybenzoic acid, and 4-hydroxyphenylacetic acid dominated in the serum (1.8-8 micromol/L). In the urine, 3-methoxy-4-hydroxyphenylacetic acid, 3-hydroxyphenylacetic acid, and 3-hydroxyphenylpropionic acid dominated and their excretion increased significantly with the level of sorghum bran in the diet. The summed phenolic acid excretion was 0.8 micromol/day in the control group and increased to 23 micromol/day for 40% sorghum bran group. The hippuric acid excretion ranged from 2.2 to 16.2 micromol/day and peaked in the 10% sorghum bran group. On the basis of chromic oxide, a nonabsorbable marker, total procyanidins and polymers disappeared progressively, and significant degradation occurred in the cecum and colon. Catechins and procyanidins in sorghum were bioavailable; however, bacteria-derived phenolic acids were the predominant metabolites of procyanidins. Procyanidins degraded in the gastrointestinal tract. Depolymerization was not observed.  相似文献   

Isoflavone glycitein diminished plasma cholesterol in female golden Syrian hamsters     

Lee SO  Renouf M  Ye Z  Murphy PA  Hendrich S 《Journal of agricultural and food chemistry》2007,55(26):11063-11067

The soybean isoflavones, daidzein, genistein, and glycitein, were hypothesized to act as cholesterol-lowering components, separate from soy protein. Pure synthetic daidzein, genistein, or glycitein (0.9 mmol/kg diet) or a casein-based control diet was fed to groups of 10 female Golden Syrian hamsters for 4 weeks. Hamsters fed glycitein had significantly lower plasma total (by 15%) and non-HDL (by 24%) cholesterol compared with those fed casein (P<0.05). Daidzein and genistein's effects on these lipids did not differ from the effects of either casein or glycitein. Plasma HDL cholesterol and triglyceride concentrations were not significantly affected by dietary treatments. The percentage of urinary recovery of the ingested dose of each isoflavone was glycitein>daidzein>genistein (33.2%, 4.6%, 2.2%, respectively), with the apparent absorption of glycitein significantly greater than that of the other isoflavones. These data suggest that glycitein's greater cholesterol-lowering effect was due to its greater bioavailability, as reflected in its urinary recovery compared with that of the other isoflavones.  相似文献   

Production of a D-glycero-D-manno-heptosyltransferase mutant of Mannheimia haemolytica displaying a veterinary pathogen specific conserved LPS structure; development and functionality of antibodies to this LPS structure     

Logan SM  Chen W  Aubry A  Gidney MA  Lacelle S  St Michael F  Kuolee R  Higgins M  Neufeld S  Cox AD 《Veterinary microbiology》2006,116(1-3):175-186

Previous structural studies of the lipopolysaccharides from the veterinary pathogens Mannheimia haemolytica (Mh), Actinobacillus pleuropneumoniae (Ap) and Pasteurella multocida (Pm) had identified a conserved inner core oligosaccharide structure that was present in all strains investigated. In order to examine the potential of this inner core structure as a vaccine, a mutagenesis strategy was adopted to interrupt a D-glycero-D-manno-heptosyltransferase gene (losB) of Mh. This gene encodes the enzyme responsible for the addition of a D-glycero-D-manno-heptose residue, the first residue beyond the conserved inner core, and its inactivation exposed the conserved inner core structure as a terminal unit on the mutant LPS molecule. Subsequent analyses confirmed the targeted structure of the mutant LPS had been obtained, and complementation with losB in trans confirmed that the losB gene encodes an alpha-1,6-D-glycero-D-manno-heptosyltransferase. Monoclonal antibodies raised in mice to this LPS structure were found to recognise LPS and whole-cells of the truncated mutant and wild-type Mh. The antibodies were bactericidal against a wild-type Mh strain and were able to passively protect mice in a model of Mh disease. This illustrates that it is possible to raise functional antibodies against the conserved inner core LPS structure.  相似文献