bluuebunny/crossref_metadata_2025 huggingface dataset:
Viscoelastic effective rheologies for modelling wave propagation in porous media
Authors: Carcione José M.
Published: October 2010

Biot's poroelastic differential equations are modified for including matrix–fluid interaction mechanisms. The description is phenomenological and assumes a solid–fluid relaxation function coupling coefficient. The model satisfies basic physical properties such as, for instance, that P‐wave velocities at low frequencies are lower than those predicted by Biot's theory. In many cases, the results obtained with the Biot (two‐phase) modelling are equal to those obtained with single‐phase elastic modelling, mainly at seismic frequencies. However, a correct equivalence is obtained with a viscoelastic rheology, which requires one relaxation peak for each Biot (P and S) mechanism. The standard viscoelastic model, which generalizes compressibility and shear modulus to relaxation functions, is not appropriate for modelling the Biot complex moduli, since Biot's attenuation is of a kinetic nature (i.e. it is not related to bulk deformations). The problem is solved by associating relaxation functions with each wave modulus. The equivalence between the two modelling approaches is investigated for a homogeneous water‐filled sandstone and a periodically layered poroelastic medium, alternately filled with gas and water. The simulations indicate that, in the homogeneous case, particle velocities in the solid skeleton, caused by a source applied to the matrix, are equivalent to viscoelastic particle velocities. In a finely layered medium, viscoelastic modelling is not, in principle, equivalent to porous modelling, due to substantial mode conversion from fast wave to slow static mode. However, this effect, caused by local fluid‐flow motion, can be simulated by including an additional relaxation mechanism similar to the squirt‐flow.
Measurement of electrical properties of contaminated soil1
Authors: Darayan S. , Liu C. , Shen L.C. , Shattuck D.
Published: October 2010

We present the measured dielectric constant and conductivity of soil samples contaminated by diesel oil. Measurements of the electrical properties of contaminated soil were carried out using a guarded‐electrode sample holder and a parallel‐plate sample holder in the frequency range 2–250 MHz. Two different soil samples were measured. Both the dielectric constant and the conductivity of the contaminated soils and uncontaminated soils are compared. The measurement results show that the change in the dielectric constant of soils before and after diesel oil contamination is small but significant. These results provide a basis for using ground‐penetrating radar or other high‐frequency electromagnetic sensors in the detection of soil contamination.
Wavelet analysis for the regional‐residual and local separation of potential field anomalies
Authors: Fedi Maurizio , Quarta Tatiana
Published: October 2010

A method based on the discrete wavelet transform was applied to the regional‐residual separation of potential fields and to the filtering of local anomalies. A specific space‐scale wavelet analysis, called multiresolution analysis, allowed decomposition of the signal with respect to a vast range of scales. Different analysing wavelets were applied to anomalies in both synthetic and real cases, but the more appropriate basis needed to be chosen by requiring the maximum compactness for the multiresolution analysis. Moreover, since such analysis was found not to be shift‐invariant, the same criterion was applied to choosing the best signal shift. Application of the technique to both synthetic and real cases produced an optimal space‐scale representation of the fields and a consistent regional‐residual separation. Furthermore, the space localization allowed a variety of filtered signals to be obtained, each one with a specific scale and local area content. Fourier and wavelet analyses were both applied to the filtering out of the intense Etna anomaly from the aeromagnetic field of Sicily. The wavelet method was more powerful, suppressing only the Etna volcano anomaly and leaving the rest of the map practically unchanged.
Wavelet power spectrum analysis of heterogeneities from sonic velocity logs
Authors: Li Xiao‐Ping
Published: October 2010

The continuous wavelet transform (CWT) is used to evaluate local variations in the power‐law exponents of sonic log data. The resulting wavelet spectrum can be compared with the corresponding global estimates obtained by conventional Fourier transform methods. In Fourier analysis, the fundamental tool used to characterize a fluctuating velocity distribution is the power spectrum. It represents the energy contained in each wavenumber and thus provides information regarding the importance of each scale of heterogeneity. However, important spatial information regarding the location of events becomes implicit in the phase angle of the Fourier transform. In this paper, it is shown how the square of the amplitude of the wavelet transform is related to the Fourier spectrum and how spatial information can be expressed in an explicit manner. Using the conservation of energy, it is shown that the average wavelet power spectrum over the total depth range is equal to the global power spectrum. A Gaussian wavelet is chosen to realize the wavelet transform. Two synthetic sonic logs with exponential and von Karman correlation functions are used to demonstrate the potential of the suggested analysis. Furthermore, the wavelet transform is applied to the KTB (Continental Deep Drilling Program) sonic log data. The wide range of applications of the CWT shows that this transform is a natural tool for characterizing the structural properties of underground heterogeneities. It offers the possibility of separating the multiscale components of heterogeneities.
Consortium approach for nurse practitioner education
Authors: Van Soeren Mary H. , Andrusyszyn Mary‐Anne , Spence Laschinger Heather K. , Goldenberg Dolly , DiCenso Alba ,   and all other members of the Nurse Practitioner Evaluation Group: S. Sidani RNPhD, D. Irvine RNPhD, A. Gafni DSc, B. Hutchison MDMSc, G. Guyatt MD MSc, S. Walter PhD, V. Bhatia RN MHSc and S. Caty RN MSc
Published: October 2010

Consortium approach for nurse practitioner education

In 1995, a 10‐university consortium approach to deliver a post‐baccalaureate primary care nurse practitioner programme funded by the Ontario Ministry of Health was launched throughout Ontario, Canada. A combination of traditional and distance teaching methods, in English and French, were used. A 5‐year research project was initiated to evaluate the entire programme, the effect of nurse practitioners on patient and health‐care system outcomes and examine practice patterns. Participants included deans and directors (n=10), regional co‐ordinators (n=5) and course developers, some of whom were also course professors (n=8). This article is a report of the evaluation of the consortium programme after the first year from the perspective of groups involved in implementation and delivery. Results of qualitative analyses of participant perceptions from researcher‐led focus groups and asynchronous electronic interviews provided the framework for the evaluation, and revealed the rationale for the consortium method, strengths, limitations and recommendations. Sharing ideas, resources and delivery and increased student access in remote areas were perceived as positive outcomes. Limitations included the short time period to develop programme content, identify and plan for distance education resources, and too little communication between universities and students. Researchers concluded that the consortium approach was effective for nurse practitioner education. Key factors identified for programme planning were communication, resources, curriculum and workload. Included among the recommendations was to allow sufficient time for role and course development before beginning a similar programme.
Women with learning disabilities: risk behaviours and experiences of the cervical smear test
Authors: Broughton Sallyanne , Thomson Karen
Published: October 2010

Women with learning disabilities: risk behaviours and experiences of the cervical smear test

This paper reports the findings of a study on the views and experiences of women with learning disabilities regarding the cervical smear test. The experience and opinions of the carers were also taken into account. The study was carried out between 1997 and 1999 in Cambridgeshire. The factors that influenced whether women with a learning disability had a smear test included: sexual activity; number of sexual partners; pregnancy; and a past history of smoking. Women with a learning disability who had a cervical smear test most often experienced pain and difficulty with the procedure. Factors that enable women with a learning disability to undergo a cervical smear test, according to their experiences, will be discussed in this paper. These include: the importance of prolonged preparation; issues surrounding communication; the giving of information; and support from the carers. The implications of these findings for collaborative working between learning disability nurses and primary healthcare professionals in clinical practice are highlighted.
Efficacy and safety of prone positioning for patients with acute respiratory distress syndrome
Authors: Breiburg Anna N. , Aitken Leanne , Reaby Linda , Clancy Richard L. , Pierce Janet D.
Published: October 2010

Efficacy and safety of prone positioning for patients with acute respiratory distress syndrome

This article presents an overview of a literature review on how prone positioning can alleviate pathophysiological changes in ARDS and improve ventilation and perfusion. Improvement of gas exchange, efficiency of oxygenation and lung function are emphasized. Literature on the pathophysiology of ARDS, and the physiological effects of prone positioning on haemodynamics and lung function is examined. There are both advantages and disadvantages in turning a patient from the supine to the prone position. There are also contraindications in rotating between the supine and prone positions. Nevertheless, by rotating patients with ARDS, it is possible to achieve a significant improvement in A‐aDO2, decrease shunting, and therefore improve oxygenation without use of expensive, invasive and experimental procedures. Placing patients with ARDS in the prone position can reduce inspiratory oxygen concentrations and peak inspiratory pressures, which minimizes the chance for barotrauma and the iatrogenic effects of hyperventilation oxygen toxicity.
Death, dying and emotional labour: problematic dimensions of the bone marrow transplant nursing role?
Authors: Kelly Daniel , Ross Sharon , Gray Benjamin , Smith Pam
Published: October 2010

Death, dying and emotional labour: problematic dimensions of the bone marrow transplant nursing role?

Bone marrow transplantation (BMT) is an established intervention for a range of conditions including those of a serious, life‐threatening nature such as leukaemias. The experience of those who fail to respond to such aggressive treatment, however, or those who die as a result of treatment‐induced complications, is currently under‐researched. In this paper the authors suggest that despite the relatively high mortality associated with BMT, cultural, biological and professional factors have contributed to a lack of attention on issues of death and dying and emotional labour within BMT care settings. Current technological, biomedical and quality of life discourses which characterize much of the BMT literature are problematic and, we suggest, may serve to disadvantage those who will not survive such procedures. In addition, the provision of effective palliative care in BMT settings remains open to review through further research and development. As a first step, the authors argue that the role of nursing needs to be reconceptualized within BMT to allow key humane concerns such as suffering and the emotional labour of care to be explored and better understood.
Backstage in the theatre
Authors: Tanner Judith , Timmons Stephen
Published: October 2010

Backstage in the theatre

Observations undertaken in the operating theatre suggested that the social environment, and certain forms of staff behaviour could be explained using the space analysis developed by Erving Goffman (1969) in The Presentation of Self in Everyday Life. In the study reported in this paper the theatre department was found to be a strongly ‘backstage’ area. However, it was also found that there were limits to this analysis, and these are explained within this article. Some practical suggestions as to how this analysis might be helpful in the management of health care institutions and the education of health care professionals are made.
Multicentre research and the WISECARE experience
Authors: Kearney Nora , Miller Morven , Sermeus Walter , Hoy Derek , Vanhaecht Kris
Published: October 2010

Multicentre research and the WISECARE experience

The benefits of collaborative research are becoming recognized increasingly within the profession of nursing due to the associated increased likelihood of funding, variety of practice settings and increased access to resources that collaboration brings. While such benefits have made collaborative research one of the most desirable strategies for achieving the goals of research, the potential problems of language and communication, culturally sensitive instruments, access to subjects, availability of technology and lack of research resources have complicated collaborative international research initiatives. Review of the literature, although encouraging such initiatives, does little to provide information regarding the processes involved in multinational collaboration or the associated advantages and disadvantages to guide those embarking on such large scale, multinational, cross‐cultural studies. The diverse meanings of collaboration within research initiatives further hamper this understanding. Positive definitions focus on aspects such as sharing expertise, making a valuable contribution to the research and ultimately shared ownership of the accomplishments of the research. One such research project led by nurses was the WISECARE project. WISECARE (Workflow Information Systems for European Nursing Care) was funded by the European Commission and aimed to improve cancer nursing practice and ultimately patient outcomes through the integration and utilization of state of the art information technology. Such a project was developed as a result of nursing's apparent invisibility within health care delivery and the problems experienced by nurses in articulating their worth within an increasingly cost‐conscious health care system. Oncology care was selected as the domain for the project not only because this speciality of nursing already has an established network of nurses throughout Europe in the European Oncology Nursing Society (EONS) but also because the practice of cancer nursing encompasses all aspects of nursing care. This paper will address the advantages and disadvantages associated with collaboration, using the WISECARE project as an example.
Research guidelines for the Delphi survey technique
Authors: Hasson Felicity , Keeney Sinead , McKenna Hugh
Published: October 2010

Research guidelines for the Delphi survey technique

Consensus methods such as the Delphi survey technique are being employed to help enhance effective decision‐making in health and social care. The Delphi survey is a group facilitation technique, which is an iterative multistage process, designed to transform opinion into group consensus. It is a flexible approach, that is used commonly within the health and social sciences, yet little guidance exists to help researchers undertake this method of data collection. This paper aims to provide an understanding of the preparation, action steps and difficulties that are inherent within the Delphi. Used systematically and rigorously, the Delphi can contribute significantly to broadening knowledge within the nursing profession. However, careful thought must be given before using the method; there are key issues surrounding problem identification, researcher skills and data presentation that must be addressed. The paper does not claim to be definitive; it purports to act as a guide for those researchers who wish to exploit the Delphi methodology.
The effects of ceftiofur sodium (Naxcel) on bovine oocyte and preimplantation embryonic development assessed by in vitro embryo production techniques
Authors: Holyoak G.R. , Wang S. , Liu G. , Bunch T.J. , Evans R.C. , Bunch T.D.
Published: October 2010

Ceftiofur sodium is a third‐generation cephalosporin antibiotic with broad spectrum bactericidal activity against Gram‐positive and Gram‐negative bacteria including the beta‐lactamase producing strains. In this study, we use in vitro techniques to examine the effects of low and high levels of ceftiofur sodium on the development of bovine oocytes/embryos during oocyte maturation, oocyte fertilization and embryo culture. A total of 8590 oocytes was used in six independent experiments, each in a randomized complete block design. Each replication within each experiment consisted of oocytes from the same abattoir collection of ovaries. There was no difference in embryo development when oocytes were exposed to ceftiofur sodium during oocyte maturation or fertilization at low (10 and 50 μg/mL) or high (100 and 200 μg/mL) concentrations. However, when fertilized oocytes were exposed to concentrations 50 μg/mL during culture, ceftiofur sodium significantly retarded embryo development (e.g. the numbers of ova developing to the morula and blastocyst stages were reduced, and a large proportion of embryos were blocked at the 8‐cell stage). We conclude that ceftiofur sodium does not appear to have detrimental effects on oocyte maturation and fertilization. However, long term exposure to high dosages of ceftiofur sodium during post‐fertilization culture adversely affects embryo development in vitro.
Bioavailability of spiramycin and lincomycin after oral administration to fed and fasted pigs
Authors: Nielsen P. , Gyrd‐Hansen N.
Published: October 2010

The disposition of spiramycin and lincomycin was measured after intravenous (i.v.) and oral (p.o.) administration to pigs. Twelve healthy pigs (six for each compound) weighing 16–43 kg received a dose of 10 mg/kg intravenously, and 55 mg/kg (spiramycin) or 33 mg/kg (lincomycin) orally in both a fasted and a fed condition in a three‐way cross‐over design. Spiramycin was detectable in plasma up to 30 h after intravenous and oral administration to both fasted and fed pigs, whereas lincomycin was detected for only 12 h after intravenous administration and up to 15 h after oral administration. The volume of distribution was 5.6 ± 1.5 and 1.1 ± 0.2 L/kg body weight for spiramycin and lincomycin, respectively. For both compounds the bioavailability was strongly dependent on the presence of food in the gastrointestinal tract. For spiramycin the bioavailability was determined to be 60% and 24% in fasted and fed pigs, respectively, whereas the corresponding figures for lincomycin were 73% and 41%. The maximum plasma concentration of spiramycin (Cmax) was estimated to be 5 μg/mL in fasted pigs and 1 μg/mL only in fed pigs. It is concluded that an oral dose of 55 mg/kg body weight is not enough to give a therapeutically effective plasma concentration of spiramycin against species ofMycoplasma,Streptoccocus,StaphylococcusandPasteurella multocida. The maximum plasma concentration of lincomycin was estimated to be 8 μg/mL in fasted pigs and 5 μg/mL in fed pigs, but as the minimum inhibitory concentration for lincomycin againstActinobacillus pleuropneumoniaeandP.multocidais higher than 32 μg/mL a therapeutically effective plasma concentration could not be obtained following oral administration of the drug. ForMycoplasmathe MIC90is below 1 μg/mL and a therapeutically effective plasma concentration of lincomycin was thus obtained after oral administration to both fed and fasted pigs.
Antibiotic effects on cytochromes P450 content and mixed‐function oxygenase (MFO) activities in the American alligator,Alligator mississippiensis
Authors: Mayeaux M. H. , Winston G. W.
Published: October 2010

There are no Food and Drug Administration (FDA)‐approved antimicrobial agents for use in cultured American alligators (Alligator mississippiensis) destined for human consumption yet some producers administer antibiotics for prophylaxis. The cytochromes P450‐dependent mixed‐function oxygenases (MFO) catalyze the oxidation of xenobiotic compounds such as drugs, pesticides and polycyclic aromatic hydrocarbons. Herein, we describe the effects of oxytetracycline, ceftazidime and enrofloxacin on the MFO system of the American alligator,Alligator mississippiensis. Juvenile alligators (4 animals/treatment) were administered these antibiotics intraperitoneally in an effort to induce hepatic microsomal cytochromes P450. Alligators treated with enrofloxacin exhibited emesis and convulsive spasms within 5 min of the initial injection. Total hepatic cytochromes P450 contents were significantly decreased in oxytetracycline‐and enrofloxacin‐pretreated alligators.In vitrohepatic microsomal benzyloxyresorufinO‐dealkylase (BROD) activity was significantly decreased by enrofloxacin pretreatment. Western blots of proteins from antibiotic‐pretreated alligator hepatic microsomes incubated with several mammalian and fish cytochromes P450 (CYP) antibodies exhibited little or no induction of CYP1A1, 2B, 2C and 2E1.In vitroincubation with enrofloxacin and oxytetracycline caused a concentration‐dependent decrease in alkyl‐substituted phenoxazone dealkylase activities catalyzed by phenobarbital‐ and 3‐methylcholanthrene‐induced alligator hepatic microsomes.
The Two‐Signal Model and ‘Self’‐Reactivity: Are They Really Compatible? A Reply to Faro & Carneiro
Authors: COHN M.
Published: October 2010

Given that the associative recognition of antigen (two signal) model permits a certain level of ‘autoreactivity’, Faro & Carneiro argue that this unavoidable ‘autoreactivity’ is required as part of the regulation of thegeneral physiology of the animal. This paper gives the author’s reply pointing out two facets of the functioning of the immune system. (1) Under an associative recognition of antigen model, the scenarios of B‐cell activation postulated by them areruled out. (2) There is no way to use a destructive ridding effector function to regulate the self/non‐self discrimination because autoimmune reactivity would accompany any postulated regulatory mechanism.
Ig‐Isotype Patterns of Primary and Secondary B Cell Responses to Plasmodium Chabaudi Chabaudi Correlate with IFN‐γ and IL‐4 Cytokine Production and with CD45RB Expression by CD4+ Spleen Cells
Authors: D'Império Lima M. R. , Alvarez J. M. , Furtado G. C. , Kipnis T. L. , Coutinho A. , Minóprio P.
Published: October 2010

In this work, the authors analysed T and B lymphocyte subsets and cytokine production in the spleen of BALB/c mice during polyclonal lymphocyte activation (primary infection) and parasite‐specific response to Plasmodium chabaudi chabaudi (secondary infection). The secondary response was evaluated in fully immunoprotected animals, 60 days after a chloroquine‐cured infection. The authors observed that in polyclonal lymphocyte activation antibody‐secreting cells of all isotypes increased, with predominance of IgG2a and IgG3 classes. At that time, IFN‐γ was largely produced, but IL‐4/IL‐5 were just slightly enhanced. In mice re‐infected after 60 days, the Ig‐isotype pattern was restricted to IgG1 and only IL–4/IL‐5 were produced. In both responses, however, the levels of IL‐2 were greatly reduced, while those of IL‐10 were enhanced to similar levels. The different involvement of Th1 and Th2 cells in both responses was confirmed through analysis of CD45RB expression by CD4+ cells. The authors observed that CD45RBhigh cells were the major CD4+ subpopulation in primary infected mice, while CD45RBlow cells predominated in 60 days re‐infected animals. Moreover, the great majority of activated (large) CD4+ cells in the primary infection belonged to the CD45RBhigh subset, while after re‐infection most of the CD4+ large had a CD45RBlow phenotype.
Activation of Human Neutrophils Induced by Immune Complexes Prepared with Cationic and Anionic Fractions of Normal IgG Antibodies
Authors: TREVANI A. S. , ANDONEGUI G. , KEMPFER C. , MALCHIODI E. , GEFFNER J. R.
Published: October 2010

The authors have recently shown that the ability of immune complexes (IC) to trigger FcγR‐dependent cell responses can be dramatically enhanced when the isoelectric point (pI) of normal IgG antibodies is increased from 5.8–8.5 to 8.5–9.8 by treatment with 1‐ethyl‐3‐2(3‐dimethylaminopropyl) carbodiimide HC1 and ethylene diamine. In the current work the authors analyse whether differences in the charge of normal IgG antibodies may also affect IC activity. Soluble IC (sIC) were prepared with (a) rabbit IgG antibodies to human IgG and anionic or cationic fractions of human IgG; and (b) bovine serum albumin (BSA) and anionic or cationic fractions of rabbit IgG anti‐BSA antibodies. Similar abilities to bind to neutrophil surface were observed for sIC prepared with both anionic (anIC) and cationic fractions of IgG (catIC). Moreover, no differences were found when neutrophil shape change, chemiluminescence (CL) emission and elastase release were induced by either anIC or catIC. As in the case of sIC, particulate IC prepared with erythrocytes (E) and anionic or cationic fractions of specific IgG antibodies (IgG‐E) showed no differences in their abilities to trigger either CL emission or ADCC. Taken together, these results suggest that the pI of normal IgG antibodies do not affect the ability of IC to trigger neutrophil responses mediated by receptors for the Fc portion of IgG antibodies (FcγR).
Docosahexaenoic and Eicosapentaenoic Acids Inhibit Human Lymphoproliferative Responses In Vitro but not the Expression of T Cell Surface Activation Markers
Authors: KHALFOUN B. , THIBAULT G. , LACORD M. , GRUEL Y. , BARDOS P. , LEBRANCHU Y.
Published: October 2010

The effects of polyunsaturated fatty acids (PUFAs: docosahexaenoic (DHA) and eicosapentaenoic (EPA) acids) on induced lymphocyte proliferation and expression of CD25α chain of interleukin‐2 receptor, CD71 and HLA‐DR were investigated. PUFAs had no effect on phytohaemagglutinin (PHA)‐induced lymphocyte agglutination, but they strongly inhibited the lymphoproliferative response to PHA. This inhibitory effect is PUFA dose‐dependent and seems to be more potent with DHA than EPA. Pre‐incubation experiments showed that lymphocytes cultured with PUFAs for 6 h, then washed and exposed to PHA, still inhibited lymphocyte proliferation. The authors also showed that this inhibitory activity was time dependent but became non‐significant when PUFAs were added after 48 h lymphocyte culture. The addition of excess exogenous human recombinant rIL‐2 partly restored PHA‐lymphocyte proliferation inhibited by EPA but not by DHA. On the other hand, the authors showed that PUFAs did not inhibit IL‐2 stimulated lymphocyte proliferation. The addition of PUFAs to cell culture medium had no inhibitory action on the PHA‐induced lymphocyte expression of CD25, CD71 and HLA‐DR. Furthermore, this effect appeared independent of eicosanoid synthesis or peroxide formation. Indeed, the inclusion of aspirin and vitamin E in the culture medium did not prevent the inhibitory effects of PUFAs on lymphocyte proliferation. Regardless of the mechanism of action, the inhibitory effect of PUFAs on activated lymphocytes may explain why some clinical trials of fish oil supplemented diets containing high amounts of DHA and EPA have been successful in improving the health status of patients suffering from inflammatory and autoimmune disorders.
TNF Production from Peripheral Blood Mononuclear Cells in Diabetic Patients after Stimulation with Alginate and Lipopolysaccharide
Authors: KULSENG B. , SKJÅK‐BRÆK G. , FØLLING I. , ESPEVIK T.
Published: October 2010

Microencapsulated pancreatic Langerhan's islets in calcium alginate gels have been used as an implantable bio‐artificial pancreas in the treatment of diabetes mellitus, but with limited success due to overgrowth of the capsule with fibroblasts and phagocytes. The authors earlier demonstrated that alginates enriched in mannuronic acid stimulate human monocytes to produce high levels of cytokines such as tumour necrosis factor (TNF), IL‐1, IL‐6. In this study the authors have measured the TNF production from peripheral blood mononuclear cells (PBMC) in different groups of insulin‐dependent diabetes mellitus (IDDM) patients after stimulation with different alginates and lipopolysaccharide (LPS). It was found that high G‐alginate did not induce TNF production in any of the groups. High‐M alginate and LPS induced a dose‐dependent TNF production in all groups and the production was significantly different from unstimulated cells. The highest TNF response was found in newly diagnosed IDDM patients and the lowest was in the controls.
Standardization of a Flow Cytometric Assay for Phagocyte Respiratory Burst Activity
Authors: VUORTE J. , JANSSON S.‐E. , REPO H.
Published: October 2010

The authors optimized the flow cytometric dichlorofluorescin (DCFH)‐oxidation assay for buffy coat neutrophil and monocyte respiratory burst activity. Sample handlings were minimized, monocytes identified with a CD14 antibody, and viability evaluated with propidium iodide. Sodium citrate was a better anticoagulant than heparin, with a more intense Yersinia enterocolitica (YER)‐induced dichlorofluorescein (DCF)‐fluorescence intensity and a higher proportion of DCF‐positive cells. EDTA was unsuitable as an anticoagulant with reduced cell viability and poor DCF response. Exposure of cells to YER, phorbol myristate acetate (PMA) or N‐formyl‐methionyl‐leucyl‐phenylalanine (FMLP) elicited two neutrophil subpopulations, one with low and the other with high forward light scattering properties. FMLP induced only a marginal DCF response, but after YER or PMA, virtually all neutrophils responded with an increased DCF production. During optimal conditions, the resulting DCF‐fluorescence histogram was two‐peaked, and the subset of cells with increased forward light scattering properties corresponded to the cells with intense DCF‐fluorescence. A similar heterogeneity was frequently but not always observed amongst monocytes. The results indicate that in the peripheral blood there are at least two neutrophil and monocyte populations. One is an effective responder to stimuli, the other exhibiting a moderate response only. Properly optimized, the DCFH‐oxidation assay may be used for evaluating neutrophil and monocyte subsets in a clinical setting.
The Predator Deterrence Function of Primate Alarm Calls
Authors: Zuberbühler Klaus , Jenny David , Bshary Redouan
Published: October 2010

It is generally assumed that alarm calls function in intraspecific communication, for example to warn close relatives about the presence of a predator. However, an alternative hypothesis suggests that, in some cases, signallers may also gain fitness benefits in directly communicating to the predator, for example by advertising perception and unprofitability to predators that depend on unprepared prey. In this study, we show that six monkey species in Taï forest, Ivory Coast, produce significantly more alarm calls to leopards than to chimpanzees, although both are notorious monkey predators. The conspicuously high vocalization rates to leopards had adaptive consequences for the monkeys. By following a radio‐collared leopard, we found that after detection and high alarm call rates the leopard gave up its hiding location and left the group significantly faster than would be expected by chance. We discuss these data with respect to the various functional hypothesis of alarm call behaviour and conclude that the high alarm call rates to leopards are part of an anti‐predator strategy in primates that may have evolved to deter predators that depend on surprise.
Accuracy of body weight prediction in Alpine ibex (Capra ibex, L. 1758) using morphometry
Authors: Bassano B. , Bergero D. , Peracino A.
Published: October 2010

The relationship between weight and body measurements of 227 Alpine ibex Capra ibex (162 males and 65 females, age range: 2–16 years) were analysed by linear and multiple regression. The animals were live‐captured across all seasons of the year, in the Western Italian Alps, 1986–1994. The relationship between weight and body measurements changed with sex and season. In male ibex, the best annual estimation of the body weight was obtained using as predictor variables the squared value of the chest girth and age. In females, the best predictive variables were age, total body length and withers height. Age was always selected as a predictor variable, when considered in the prediction models. The use of chest girth and the squared value of the chest girth as predictive variables in the regression equation, being the most highly correlated linear measurements with total weight, did not result in an accurate prediction of ibex body weight. The best prediction was obtained using age and different linear measurements in stepwise multiple regression, nevertheless the standard error of the estimate and the magnitude of the 95% prediction interval were great. The use of linear measurements cannot be considered accurate nor precise predictors of body weight in Alpine ibex.
Effects of different feeding and housing conditions on dry matter content and consistency of faeces in sows
Authors: Tabeling R. , Schwier S. , Kamphues J.
Published: October 2010

Summary In a study with sows at various stages of the reproductive cycle, the effects of parturition, feed quantity and composition (content and type of crude fibre), exercise and access to water on dry matter content, and consistency of faeces were estimated. Parturition caused an increase in the dry matter content and reduced the defaecation frequency. The restriction of feed amounts in the last days of gestation and the change to lactation feed with reduced crude fibre content (6–3% in feed) intensified the physiologically occurring increase of the dry matter content. Moving activity and the amount of water ingested had only a small insignificant effect on the moisture of the faeces. The faeces became markedly softer when large amounts of fermentable fibre were used in the diet. The risk for constipation in periparturient sows increases when feed amounts and fibre content in the diet are strongly reduced. Therefore, it is recommended to offer sows daily minimum amounts of a diet (<2 kg) containing >7–8% crude fibre (including a highly fermentable fibre to improve faeces consistency) especially on the days near parturition.
Hand rearing of pet birds – feeds, techniques and recommendations
Authors: Wolf P. , Kamphues J.
Published: October 2010

The comparison of the contents of nutrients determined in commercial hand rearing diets with the nutrient requirements of growing budgerigars and lovebirds estimated by the factorial method revealed satisfactory protein, lysine and arginine concentrations. Regarding sulphur amino acids, a number of products showed marginal methionine and cystine contents. Mineral contents generally met all requirements and were even excessive in some cases. Ultimately, the results gained in this study demonstrate that nestlings’ substantial requirements for sulphur amino acids for plumage development are often underestimated, while their calcium requirements in connection with bone mineralization are frequently overestimated. The primary obstacle to successful hand rearing, however, probably lies not so much in energy and nutrient contents, but rather – as revealed by first results of feeding trials with lovebirds – in the passage of the suspended diet through the gastrointestinal tract (e.g. crop disorders) and/or errors regarding feed quantities and feeding frequency.
Investigations on feathering, feather growth and potential influences of nutrient supply on feathers’ regrowth in small pet birds (canaries, budgerigars and lovebirds)
Authors: Wolf P. , Rabehl N. , Kamphues J.
Published: October 2010

The aim of this study was to quantitate feathering in several companion birds. Besides the ratio of feathers to whole body mass, feather length as well as feather weight were of interest. Furthermore, data on feather loss and growth rates were estimated. In general, it could be observed that the proportion of feathers relative to body mass varied between 14 (canaries) and 7.4% (lovebirds). Feather losses (outside the moult period) amounted to an average of 6.65 (canaries), 8.98 (budgerigars), and 8.43 (lovebirds) mg/bird/day respectively or 37 (canaries), 20 (budgerigars), and 17 (lovebirds) mg/100 g body weight/day (values of interest in calculating of protein requirements for maintenance). In canaries, the average growth rate of the developing feathers amounted to 2 mm/day. In contrast to the onset of feather regeneration, the growth rate of new feathers leaving the follicle was not influenced by the supplements used here. The regeneration period (first measurable feather growth) of a plucked pinion can be used as an indicator and objective parameter to test potential nutritional influences. Parallel to the improvement of nutrient supply the rates of feather losses and also replacement increased, whereas the rates decreased when seed mixtures without any addition of minerals, sulphurous amino acids, and vitamins were fed.
Dioxin residues in the edible tissue of broiler chicken*
Authors: Iben C. , Böhm J. , Tausch H. , Leibetseder J. , Luf W.
Published: October 2010

The aim of this study was to determine the contamination of broiler chicken with polychlorinated dibenzodioxins and dibenzofurans (PCDD/Fs) after feeding either uncontaminated feed or feed contaminated with 1, 2 or 4 ng/kg toxic equivalents (TEQ). The feed was mixed with pure substances of PCDD/Fs to get the intended contamination. Ten groups of seven 1‐day‐old chickens each were housed in special cages for broiler fattening. The fattening period lasted for 6 weeks. The contaminated feed was given for either 2, 4, or 6 weeks, one group received uncontaminated feed (control group). After slaughtering the edible parts of the chickens breast and leg including the skin were homogenized. Body weight gain and feed conversion (kg feed/kg body weight gain) were in the normal range (final weight 1.98 ± 0.07 kg; feed conversion 1.74 ± 0.03). One kilogram edible tissue contained an average of 21.2 ± 4.1% of the total TEQ‐intake in all groups. The PCDD/Fs residues in the edible tissues significantly correlated with the amount of PCDD/Fs‐intake (r = 0.99; Pearson correlation). There was no decrease in dioxin residues (% of total PCDD/Fs intake) after a 2 or 4 weeks withdrawal period. The results of this trial predict that a threshold value of 2 pg/g chicken fat can be met if the PCDD/Fs content in chicken feed is not higher than 0.4 ng/kg.
The course of some bone remodelling plasma metabolites in healthy horses and in horses offered a calcium‐deficient diet
Authors: De Behr V. , Daron D. , Gabriel A. , Remy B. , Dufrasne I. , Serteyn D. , Istasse L.
Published: October 2010

An inquiry was carried out to assess the concentrations of plasma metabolites related to bone remodelling in 21 saddle horses of Warmblood breed aged 4–26 years, five draught horses of Ardennes breed aged 4–10 years, and 10 Ardennes foals aged 9–11 months. They were fed according to normal feeding practice in Belgium. The changes in some bone remodelling plasma metabolite concentrations were studied when an unbalanced diet was offered and later corrected for four Warmblood horses. Bone formation was evaluated by bone alkaline phosphatase (BALP), total alkaline phosphatase (TALP) and osteocalcin (bone gla‐protein, OC). Bone resorption was assessed by hydroxyproline (HYP). Total calcium, ionized calcium, phosphorus (P) and 25‐hydroxyvitamin D3 [25‐(OH)D] concentrations were more or less constant. The comparison of four bone remodelling factors between the Ardennes and Warmblood horses showed higher concentrations in the Ardennes breed. Bone marker concentrations decreased according to age. The correction of the unbalanced Ca : P diet induced inconsistent effects at plasma level. The interpretation of the different bone parameters appeared to be difficult if not associated with other parameters such as a complete anamnesis and clinical examination of the animal in addition to dietary evaluation.
Studies on feed digestibilities in captive Asian elephants (Elephas maximus)
Authors: Clauss M. , Loehlein W. , Kienzle E. , Wiesner H.
Published: October 2010

In order to test the suitability of the horse as a nutritional model for elephants, digestibility studies were performed with six captive Asian elephants on six different dietary regimes, using the double marker method with acid detergent lignin as an internal and chromium oxide as an external digestibility marker. Elephants resembled horses in the way dietary supplements and dietary crude fibre content influenced digestibility, in calcium absorption parameters and in faecal volatile fatty acid composition. However, the absolute digestibility coefficients achieved for all nutrients are distinctively lower in elephants. This is because of much faster ingesta passage rates reported for elephants. No answer is given to why elephants do not make use of their high digestive potential theoretically provided by their immense body weight. Differences in volatile fatty acid concentrations between these captive elephants and those reported from elephants from the wild are in accord with a reported high dependence of free‐ranging elephants on browse forage.
Serum β‐carotene and α‐tocopherol in horses fed β‐carotene via grass‐meal or a synthetic beadlet preparation with and without added dietary fat
Authors: Kienzle E. , Kaden C. , Hoppe P. P. , Opitz B.
Published: October 2010

The serum response of β‐carotene as an indicator of bioavailability was compared after feeding β‐carotene (0.8 mg/kg body weight) either from grass meal or a synthetic beadlet preparation (LucarotinTM). Both were each given without or with added dietary vegetable fat (2–2.5% vs. 6.6% fat in dry matter) in a Latin square design with four horses. The nutritionally complete diet was supplemented with α‐tocopherol (4 mg/kg body weight). Each treatment period (4 weeks, two serum samples) was followed by a washout period of 4 weeks with low intakes of β‐carotene (traces) and α‐tocopherol (0.5 mg/kg body weight). Within 4 weeks of supplementation, serum β‐carotene increased about 10‐fold, from a mean initial concentration of 0.05–0.53 μmol/l. There was no effect of β‐carotene source and of fat addition, respectively. Faecal excretion of β‐carotene ranged from 55 to 81% of intake. No β‐carotene was detected in any urine sample. Serum α‐tocopherol (across all time points and animals, n = 64) was 14.5 μmol/l. During supplementation, the values were significantly higher than during washout‐periods. Additional dietary fat did not affect the serum response. Faecal excretion of α‐tocopherol ranged from 69 to 121% of intake. Fat addition resulted in a significant decrease of serum cholesterol. In conclusion, the natural and the synthetic source of β‐carotene showed significant and identical bioavailability independent of additional fat.
Influences of stage of lactation, teat position and sequential milk sampling on the composition of domestic cat milk (Felis catus)
Authors: Jacobsen K. L. , DePeters E. J. , Rogers Q. R. , Taylor S. J.
Published: October 2010

Milk from 11 domestic shorthair cats (Felis catus;n = 7 fed dry low‐fat diet,n = 4 fed dry high‐fat diet) was collected weekly for 6 weeks following parturition, and analysed for total solids (TS), crude protein (CP), fat, lactose and ash. Samples were collected in 1‐ml sequential fractions to determine whether within‐sampling changes in composition existed. Samples of extracted milk fat were also analysed for fatty acid content. Two commercial kitten milk replacers were analysed according to the same procedures utilized for milk samples. In statistical analyses individual cat, diet, stage of lactation, litter size, and teat position influenced concentrations of milk components; parity and sequential sampling had no effect. Averaged cat milk was 27.9% TS, and 8.7% CP, 12.7% fat, 4.2% lactose and 1.3% ash (on a wet basis). Milk protein percentage increased over lactation for both diet groups, but fat percentage increased only for queens fed the high‐fat diet. Milk replacers were lower in fat and protein content than milk from queens, and had considerably lower levels of arachidonic acid. Data from this study contribute to the limited information available regarding the composition of domestic cat milk, and give possible reasons for poor growth occasionally observed in kittens fed unsupplemented commercial milk replacers.
The effect of dietary oxidized fats on the antioxidant status of erythrocytes and their susceptibility to haemolysis in rats and guinea pigs
Authors: Keller U. , Brandsch C. , Eder K.
Published: October 2010

Three experiments were carried out with rats (experiments 1 and 2) and guinea pigs (experiment 3) to study the effect of oxidized fats, in interaction with dietary concentrations of vitamins E and C, on the antioxidant status of erythrocytes and the rate of haemolysis. In experiment 1, diets with fresh or thermoxidized fats, containing either 25 or 250 mgα‐tocopherol equivalents/kg were used; experiment 2 included diets with fresh or thermoxidized fats, containing 25 mgα‐tocopherol equivalents/kg; in experiment 3, besides a control diet with a fresh fat, diets containing thermoxidized fats with various concentrations of Vitamin E (35 vs. 175 mgα‐tocopherol equivalent/kg) and Vitamin C (300 vs. 1000 mg/kg) were used. Rats and guinea pigs fed diets with oxidized fats had reduced concentrations of glutathione in erythrocytes as compared with animals fed the fresh fat diets. In rats fed oxidized fats, the activity of catalase and in guinea pigs fed oxidized fats, the activity of glutathione peroxidase plus the concentration ofα‐tocopherol was reduced in erythrocytes as compared with animals fed the equivalent fresh fat diets. The concentrations ofα‐tocopherol in erythrocytes were increased by both, Vitamin E and Vitamin C while the concentrations of glutathione were independent of the concentrations of those vitamins in the diets. Erythrocytes of guinea pigs fed oxidized fats also showed an increased susceptibility to haemolysis during incubation in hypotonic salt solutions; this effect could be improved by increasing the concentrations of both, Vitamin E and Vitamin C. Parameters ofin vivohaemolysis (activities of lactate dehydrogenase and acidic phosphatase and concentrations of potassium and free haemoglobin in plasma) were not adversely affected in rats and guinea pigs fed the oxidized fats as compared with animals fed the fresh fats. The study shows that dietary oxidized fats reduce the antioxidant status of erythrocytes and increase their susceptibility against haemolysis but do not increase the rate of haemolysisin vivo.