Influence of environmental enrichment on welfare-related behavioural and physiological parameters in growing pigs

Three hundred and twenty pigs were reared from birth to slaughter at 21 weeks in either barren or enriched environments. The barren environments were defined as intensive housing (slatted floors and minimum recommended space allowances) and the enriched environments incorporated extra space including an area which contained peat and straw in a rack. Behavioural observations showed that environmental enrichment reduced time spent inactive and rime spent involved in harmful social and aggressive behaviour (P

Behavioural and physiological responses of shelter dogs to long-term confinement

In Italy, National Law (281/1991) prohibits euthanasia of shelter dogs if they are not dangerous or suffering seriously. Adoption rates in rescue shelters are often lower than entrance rates, leading inevitably to overcrowded facilities where animals are likely to spend the rest of their lives in kennels. In this situation, housing conditions (i.e. space provided, environmental, and social stimulation) may have an impact on canine welfare. In this research project, the effects of two different forms of housing (group- and pair housing) on long-term shelter dogs were compared using behavioural and physiological parameters. Observational data and saliva samples were collected from dogs exposed to both experimental settings; behaviour and cortisol concentration levels were used as welfare indicators. Pair housing offered fewer social and environmental stimuli and behavioural analysis showed a significant decrease in locomotor, exploratory, and social behaviour. Cortisol levels show that this parameter varied independently of housing conditions. Although this study found no evidence suggesting that one form of confinement reduced animal welfare more than the other (e.g. in terms of abnormal behaviour, or higher cortisol concentrations), the type of confinement did affect the expression of a variety of behaviours and these variations should not be ignored with respect to housing decisions for long-term shelter dogs.

The effect of feeding a high fibre diet on the welfare of sows housed in large dynamic groups

This study assessed the effect of increasing fibre levels in the concentrate ration on the welfare of sows housed in a large dynamic group. One hundred and twelve Large White x Landrace sows were allocated to one of two treatments over six replicates. Treatments were as follows: (i) High Fibre diet (similar to 15% CF [Crude Fibre]), and (ii) Control diet (similar to 5% CF). Treatments were applied to two separate dynamic groups each containing 33 (+/- 3) sows in a cross-over design, after three replicates the treatments were switched between the groups. Approximately nine sows were replaced in each of these groups at 3-week intervals (each replacement constituting a replicate of the study). Sows on the high fibre diet spent a greater percentage of time lying (High Fibre: 43.8, Control. 28.0, SEM 3.25%), while sows on the control diet spent more time sham chewing (High Fibre: 7.2, Control: 28.8, SEM 1.55%). Sows newly introduced to the group on the high fibre treatment spent proportionally more time in the kennel areas compared to newly introduced sows in the control treatment (High Fibre. 0.893, Control. 0 788, SEM 5 10) In general, aggression occurred at a very low frequency and overall levels did not differ between treatments (High Fibre: 0.005, Control: 0.003, SEM 0.0007 [occurrences per min)). However, sows in the control treatment performed head thrusting (High Fibre: 0.02, Control: 0.00, SEM 0.001 [occurrences per mini), and biting behaviour (High Fibre. 002, Control. 0.01, SEM 0.002 [occurrences per min]) more frequently than sows on the high fibre diet. There was no effect of treatment on physiological parameters such as plasma cortisol (High Fibre: 1.34, Control: 1.44, SEM 0.114 ng ml(-1)) or haptoglobin levels (High Fibre. 0.73, Control. 0.64, SEM 0.080 mg ml(-1)). In summary, provision of a high fibre diet had a positive effect on the welfare of group-housed dry sows Sows on the high fibre treatment spent more time resting in the kennel areas, less time performing stereotypic behaviours and showed a reduction in some aggressive behaviours relative to sows fed the control diet.

Molecular biology: the key to personalised treatment in radiation oncology?

We know considerably more about what makes cells and tissues resistant or sensitive to radiation than we did 20 years ago. Novel techniques in molecular biology have made a major contribution to our understanding at the level of signalling pathways. Before the “New Biology” era, radioresponsiveness was defined in terms of physiological parameters designated as the five Rs. These are: repair, repopulation, reassortment, reoxygenation and radiosensitivity. Of these, only the role of hypoxia proved to be a robust predictive and prognostic marker, but radiotherapy regimens were nonetheless modified in terms of dose per fraction, fraction size and overall time, in ways that persist in clinical practice today. The first molecular techniques were applied to radiobiology about two decades ago and soon revealed the existence of genes/proteins that respond to and influence the cellular outcome of irradiation. The subsequent development of screening techniques using microarray technology has since revealed that a very large number of genes fall into this category. We can now obtain an adequately robust molecular signature, predicting for a radioresponsive phenotype using gene expression and proteomic approaches. In parallel with these developments, functional magnetic resonance imaging (fMRI) and positron emission tomography (PET) can now detect specific biological molecules such as haemoglobin and glucose, so revealing a 3D map of tumour blood flow and metabolism. The key to personalised radiotherapy will be to extend this capability to the proteins of the molecular signature that determine radiosensitivity.

Impaired endothelium-dependent vasodilatation is a novel predictor of mortality in intensive care

Objective: Endothelial function may be impaired in critical illness. We hypothesized that impaired endothelium-dependent vasodilatation is a predictor of mortality in critically ill patients.
Design: Prospective observational cohort study.
Setting: Seventeen-bed adult intensive care unit in a tertiary referral university teaching hospital. Patients: Patients were recruited within 24 hrs of admission to the intensive care unit.
Interventions: The SphygmoCor Mx system was used to derive the aortic augmentation index from radial artery pulse pressure waveforms. Endothelium-dependent vasodilatation was calculated as the change in augmentation index in response to an endothelium-dependent vasodilator (salbutamol).
Measurements and Main Results: Demographics, severity of illness scores, and physiological parameters were collected. Statistically significant predictors of mortality identified using single regressor analysis were entered into a multiple logistic regression model. Receiver operator characteristic curves were generated. Ninety-four patients completed the study. There were 80 survivors and 14 nonsurvivors. The Simplified Acute Physiology Score II, the Sequential Organ Failure Assessment score, leukocyte count, and endothelium-dependent vasodilatation conferred an increased risk of mortality. In logistic regression analysis, endothelium-dependent vasodilatation was the only predictor of mortality with an adjusted odds ratio of 26.1 (95% confidence interval [CI], 4.3-159.5). An endothelium-dependent vasodilatation value of 0.5% or less predicted intensive care unit mortality with a sensitivity of 79% (CI, 59-88%) and specificity of 98% (CI, 94-99%).
Conclusions: In vivo bedside assessment of endothelium-dependent vasodilatation is an independent predictor of mortality in the critically ill. We have shown it to be superior to other validated severity of illness scores with high sensitivity and specificity.

Decisional responsibility for mechanical ventilation and weaning: an international survey

Introduction: Optimal management of mechanical ventilation and weaning requires dynamic and collaborative decision making to minimize complications and avoid delays in the transition to extubation. In the absence of collaboration, ventilation decision making may be fragmented, inconsistent, and delayed. Our objective was to describe the professional group with responsibility for key ventilation and weaning decisions and to examine organizational characteristics associated with nurse involvement.

Methods: A multi-center, cross-sectional, self-administered survey was sent to nurse managers of adult intensive care units (ICUs) in Denmark, Germany, Greece, Italy, Norway, Switzerland, Netherlands and United Kingdom (UK). We summarized data as proportions (95% confidence intervals (CIs)) and calculated odds ratios (OR) to examine ICU organizational variables associated with collaborative decision making.

Results: Response rates ranged from 39% (UK) to 92% (Switzerland), providing surveys from 586 ICUs. Interprofessional collaboration (nurses and physicians) was the most common approach to initial selection of ventilator settings (63% (95% CI 59 to 66)), determination of extubation readiness (71% (67 to 75)), weaning method (73% (69 to 76)), recognition of weaning failure (84% (81 to 87)) and weaning readiness (85% (82 to 87)), and titration of ventilator settings (88% (86 to 91)). A nurse-to-patient ratio other than 1:1 was associated with decreased interprofessional collaboration during titration of ventilator settings (OR 0.2, 95% CI 0.1 to 0.6), weaning method (0.4 (0.2 to 0.9)), determination of extubation readiness (0.5 (0.2 to 0.9)) and weaning failure (0.4 (0.1 to 1.0)). Use of a weaning protocol was associated with increased collaborative decision making for determining weaning (1.8 (1.0 to 3.3)) and extubation readiness (1.9 (1.2 to 3.0)), and weaning method (1.8 (1.1 to 3.0)). Country of ICU location influenced the profile of responsibility for all decisions. Automated weaning modes were used in 55% of ICUs.

Conclusions: Collaborative decision making for ventilation and weaning was employed in most ICUs in all countries although this was influenced by nurse-to-patient ratio, presence of a protocol, and varied across countries. Potential clinical implications of a lack of collaboration include delayed adaptation of ventilation to changing physiological parameters, and delayed recognition of weaning and extubation readiness resulting in unnecessary prolongation of ventilation.

Low-power radio telemetry: the potential for remote patient monitoring

Radio-based signalling devices will play an important role in future generations of remote patient monitoring equipment, both at home and in hospital. Ultimately, it will be possible to sample vital signs frompatients, whatever their location and without them necessarily being aware that a measurement is being taken. This paper reviews currentmethods for the transmission by radio of physiological parameters over ranges of 0.3, 3 and 30 m, and describes the radiofrequency hardware required and the carrier frequencies commonly used. Future developments, including full duplex systems and the use of more advanced modulation schemes, are described. The paper concludeswith a case studyof a humantemperature telemeter built to indicateovulation. Clinical results clearly show the advantage to be had in adopting radio biotelemetry in this instance.

The effect of hypoxia on propranolol clearance during antegrade and retrograde flow in the isolated perfused rat liver preparation

We investigated, using the single-pass isolated perfused rat liver preparation, whether the centrilobular location of hepatic oxidative drug metabolism could be a contributing factor to the marked sensitivity of drug oxidation to hypoxia. Livers (N = 7) were each perfused for 130 min with 2 micrograms/mL (+)-propranolol, a drug metabolized almost entirely by oxidation in the rat. The direction of flow was reversed after 60 min, the order of flow direction being randomized. Normal oxygenation was used during the first 30 min of antegrade and of retrograde perfusion, but in the second 30 min perfusate was equilibrated with a N2/O2 mixture designed to reduce hepatic oxygen delivery by half. During normal oxygenation there was no significant difference between antegrade and retrograde perfusion in hepatic oxygen delivery and physiological parameters such as oxygen consumption and extraction, perfusion pressure and bile flow. During hypoxia, mean oxygen delivery was slightly lower with retrograde perfusion (retrograde: mean = 2.37 mumol/min/g liver, range = 1.56-3.17; antegrade: mean = 2.90 mumol/min/g liver, range = 1.96-4.08; P = 0.04), but there was no significant difference in physiological parameters within each liver (P > 0.05). Propranolol clearance during normal oxygenation was similar to the perfusion rate (10 mL/min) and was the same for both directions of perfusion (antegrade 9.88 +/- 0.07 mL/min, retrograde 9.88 +/- 0.13 mL/min, P > 0.05). Hypoxia reduced propranolol clearance substantially, but the decrease was significantly greater with antegrade perfusion (5.65 +/- 1.89 mL/min) than with retrograde perfusion (6.76 +/- 1.95 mL/min, P = 0.014). Oxidative drug metabolism is located primarily in the centrilobular zone and sinusoidal oxygen concentration is lowest in the "downstream" zone with both antegrade and retrograde perfusion. These findings suggest that the centrilobular location of propranolol metabolism may influence the effect of hypoxia on propranolol elimination, but is not a major contributor to the marked sensitivity of propranolol elimination to hypoxia antegrade perfusion.

Physiological effects of platyhelminth FMRFamide-related peptides (FaRPs) on the motility of the monogenean Diclidophora merlangi

The actions of known platyhelminth FaRPs on the contractility of whole-worm preparations of the monogenean, Diclidophora merlangi have been examined in vitro for the first time. All of the peptides tested had excitatory effects on the motor activity of the worm. The order of potency for the peptides tested was: YIRFamide > GYIRFamide = RYIRFamide > GNFFRFamide = FLRFamide. However, although YIRFamide was more potent than GYIRFamide, the latter was the most efficacious on each of the motility parameters (tension, contraction amplitude and contraction frequency) examined at concentrations greater than or equal to 0.1 mu M. Serotonin, which stimulates contractility in the worm was used as a positive control. The excitatory activity of turbellarian and cestode neuropeptides on a monogenean indicates at least some structural similarities in the neuropeptide receptors of these classes of flatworm.

Blood: Tests used to assess the physiological and immunological properties of blood.

The properties of blood and the relative ease of access to which it can be retrieved make it an ideal source to gauge different aspects of homeostasis within an individual, form an accurate diagnosis, and formulate an appropriate treatment regime. Tests used to determine blood parameters such as the erythrocyte sedimentation rate, hemoglobin concentration, hematocrit, bleeding and clotting times, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration, mean cell volume, and determination of blood groups are routinely used clinically, and deviations outside the normal range can indicate a range of conditions such as anemia, pregnancy, dehydration, overhydration, infectious disease, cancer, thyroid disease, and autoimmune conditions, to mention a few. As these tests can be performed relatively inexpensively and do not require high levels of technical expertise, they are ideally suited for use in the teaching laboratory, enabling undergraduate students to link theory to practice. The practicals described here permit students to examine their own blood and that of their peers and compare these with clinically accepted normal ranges. At the end of the practicals, students are required to answer a number of questions about their findings and to link abnormal values to possible pathological conditions by answering a series of questions based on their findings.