Welfare indicators in laying hens in relation to nest exclusion.

Consumer concerns about the welfare of laying hens are increasing, leading to increased interest in identifying reliable ways to assess welfare. The present study evaluated invasive and non-invasive welfare indicators in relation to a stressful challenge. The study included 126 Lohmann Selected Leghorn hens housed in furnished cages. Welfare indicators were measured between 61 and 70 wk of age in birds excluded from their nests for 5 consecutive d and control birds that had continuous access to nests. Baseline recordings were carried out in both groups prior to and post exclusion period. The assessed indicators were: corticosterone metabolites in droppings (FCM), corticosterone concentration in yolk, corticosterone concentration in plasma, irregularities of eggshells, heterophil to lymphocyte (H:L) ratio, tonic immobility duration, and feather cover. Behavioral observations showed that the birds had a clear preference for using the secluded nest sites, confirming that they were likely to perceive nest exclusion as an undesirable experience. Further, elevated levels of FCM in droppings, yolk corticosterone concentrations, H:L ratios and irregular eggshells were detected in both nest deprived and control birds during the exclusion. This suggests that these indicators were able to detect an increased stress response arising from nest deprivation, and it is hypothesized that the stress spread to birds in adjacent cages with access to nests. There was a positive and consistent correlation between FCM in droppings and eggshell irregularities, also supporting the use of eggshell irregularities as a potential non-invasive welfare indicator. However, the pattern of the stress response varied between indicators and correlations were generally few and inconsistent, highlighting the complexity of the relationship among welfare indicators.

Welfare and performance in layers following temporary exclusion from the litter area on introduction to the layer facility.

When introduced to the laying facility, pullets are sometimes temporarily excluded from the litter area in order to help them locate food and water, and to prevent floor-laid eggs. This procedure is not permitted in Sweden, because it involves denying access to both litter and space, which may have a negative effect on bird welfare. The present study investigated how the welfare and performance of layers were affected by this temporary exclusion on introduction of hens to the laying facility. The study included 600 floor-reared Dekalb White layers obtained at 16 wk age and housed in 6 groups of 100 in a conventional single-tier floor-laying system. Birds were either given full access to the litter area during the whole study or were excluded from the litter area during the first 2 wk after transfer to the laying facility. From 18 to 72 wk age, birds in both treatments had full access to the litter area. Excluding birds from the litter area for 2 wk resulted in better feather cover and reduced fearfulness, according to novel object and tonic immobility tests. Furthermore, birds initially excluded from the litter area produced eggs with a lower proportion of shell irregularities than birds with full access to the litter area throughout. No difference was found in corticosterone metabolites in droppings rate of lay, mortality, or proportion of floor-laid eggs. In conclusion, none of the parameters studied indicated that the welfare of laying hens was compromised by temporary exclusion from the litter area on introduction to the laying facility. In fact, some of the data suggested that bird welfare had improved.

Enriched cages for groups of laboratory male rats and their effects on behaviour, weight gain and adrenal glands.

We investigated if there were any negative effects on the behaviour and physiology of rats housed in groups of five in two types of enriched cages and compared them with paired-housed rats housed in traditional cages. Eighty-four male Wistar and Sprague-Dawley rats were housed in an enriched rat cage (ERC), a rebuilt rabbit cage (RRC) or a Makrolon III cage (MC) system from 5-16 weeks of age with access to different enrichments. Recordings of behaviour and cage use (3 × 24 h video recording), weekly weighing, measuring food consumption four days/week and water consumption two days/week, were carried out. The rats' muscle strength was assessed using the 'inclined plane' at the end of the study, and after euthanasia the adrenal glands were removed and weighed. Being in the shelter was the most common behaviour in the ERC and RRC groups. In the MC group, which lacked a shelter, rats performed the highest percentage of lying, grooming, rearing, play fighting and manipulating paper shreds. Rats in the RRC had the highest percentage of standing and manipulating gnawing sticks. Water consumption was higher in MC than in ERC and RRC rats. Rats from the RRC managed to remain at a steeper angle on the 'inclined plane' than rats from the MC. There were no significant effects of cage type on weight gain, food consumption or relative weights of adrenal glands. In conclusion, male rats kept in groups of five in larger enriched cages benefited from the enrichments, and no negative effects were found in the larger groups.

Influence of crate height during slaughter transport on the welfare of male turkeys.

1. Poultry are usually transported in crates which provide the birds with very limited space. Slaughter transport of male turkeys is often carried out using crates that are 40 cm or less in height where it is not possible for them to stand up. There is little information on how this physical restriction over many hours affects the birds. 2. The aim of the study was to compare the welfare of male turkeys transported in crates 40 cm and 55 cm in height. Observations on the birds' behaviour during lairage, carcass damage and meat quality were carried out after four commercial slaughter transport journeys. 3. Birds in 40 cm crates panted more and lay down more than birds in 55 cm crates during lairage. A large percentage of the carcasses had some damage. Significantly more birds from the 55 cm crates had scratches on their backs than birds from the 40 cm crates. There was no significant difference in meat quality between birds transported in the two crate heights. 4. Both positive and negative effects of increased crate height were established and there is no evidence from this study that merely increasing crate height improves turkey welfare. Other solutions should therefore be sought in order to improve the welfare of birds during transport.

Visual lateralization and development of spatial and social spacing behaviour of chicks (Gallus gallus domesticus).

We investigated whether the development of spatial behaviour of the domestic chicken is influenced by light exposure of the embryo, as is known to be the case for some other lateralized visual functions. Ninety-six chicks were incubated in the dark or exposed to light during the final days of incubation. Half of the chicks in each group had the experience of moving behind opaque screens from 10 to 12 days of age. The other half were given transparent screens as a control. Chicks were tested in a detour test and a rotated floor test and their dispersal in groups was observed in larger pens. In the rotated floor test, chicks that had had experience with opaque screens used distal cues significantly more often than chicks that had experience with transparent screens (P=0.042), regardless of whether they had been exposed to light before hatching or incubated in the dark. There were no significant differences between treatments in the detour test or in the dispersal behaviour. Hence, visual lateralization has no influence on the development of the spatial behaviour that we tested, whereas the occlusion experience is quite specific and results in shifted attention to distal spatial cues.

The effect of lexical, pragmatic, and morphological violations on reading time and deviance ratings of English and German sentences.

Effects on reading time and deviance ratings of word-choice violations were studied at the surface code, propositional textbase, and situation model levels of representation in German and English sentences. Lexical violations (propositional textbase level) such as The housewife massaged the bread dough were rated as more deviant from normal language than were pragmatic violations (situation model level) such as The police officer shot the parking violator, although the pragmatic violations took longer to comprehend. The addition of a morphological (surface code) violation through the wrong form of an article (e.g., a ugly car) decreased reading time but only in cases where that material was deeply processed and where the morphology carried substantial syntactic information (e.g., in German, the definite article carries case, gender, and number information). The results thus confirmed the operation of comprehension strategies at multiple levels of representation and identified some cross-linguistic generality in comprehension and some language differences.

Research involving persons with cognitive impairments: results of a survey of Alzheimer disease research centers in the United States.

Research involving persons with cognitive impairments presents ethical and practical challenges, including how to obtain valid informed consent. We asked the directors of the 29 U.S. research centers funded by the National Institute on Aging as "Alzheimer Disease Centers" to provide us with policies or guidelines used in their centers or associated institutions with regard to research involving cognitively impaired subjects. Twenty-four of the 29 centers (83%) responded. Five institutions (21%) had authored their own institutional policies, seven (29%) used guidelines issued by the Department of Health and Human Service's Office for Protection from Research Risks, and 12 (50%) had no policy or guidelines. The five institutional policies addressed a variety of issues, including obtaining consent from cognitively impaired subjects or their authorized representatives, subjects' assent to research participation, and guidance concerning determination of subjects' intellectual capacity. A well-written policy on the protection of cognitively impaired research subjects is one way a research institution demonstrates that it gives serious attention to the rights and welfare of these vulnerable persons. We recommend that all institutions conducting such research author written policies articulating appropriate safeguards for these vulnerable subjects. To promote the protection of cognitively impaired subjects, federal agencies and other funding groups may want to consider requiring written institutional policies as one condition of receiving funds to conduct such research.

The impact of disease severity on the informed consent process in clinical research.

PURPOSE: To assess the efficacy of informed consent in subjects differing in disease severity, ranging from those with immediately life-threatening disease to healthy volunteers. SUBJECTS AND METHODS: A total of 127 subjects, enrolled in four types of clinical research protocols, were tested. Subjects completed questionnaires before entry into the protocol, within 24 hours of signing the primary protocol's consent document, and 4 to 6 weeks after entry. RESULTS: Healthy volunteers retained the most information about risks and side effects, and severely ill Phase I subjects retained the least (P <0.0001). Phase I and II subjects had the best long-term retention of information about procedures, whereas Phase III subjects and healthy volunteers retained the least (P <0.001). Information about the scientific purpose and confidentiality of data were retained best by symptom-free, Phase III subjects (P <0.05). Phase I subjects entered the study primarily for treatment purposes, and the consent document was rated less useful by subjects with more advanced disease (P <0.05). CONCLUSIONS: Subjects with differing disease processes and illness severities focused on and retained different aspects of experimental protocols for dissimilar reasons. During the informed consent process, research staff should inquire of potential subjects' personal goals for participating in experimental protocols and develop means for ensuring subjects' understanding of the inherent risks and alternative interventions available.

Bioethics at the National Institutes of Health.

The National Institutes of Health is the largest biomedical research institution in the world. It has become one of the world's most highly respected research centers in part because of its efforts over the years to provide the research community with leadership in both the ethical and scientific parameters of research involving humans. As its 113th birthday approaches at the turn of the century, its great legacy is providing an environment to stimulate and nourish the diversity and creativity of ideas, and thereby enable science to progress. This research must continue to be guided and tempered by consistent and critical federally-supported ethical analyses.

Long-term administration of 3'-azido-2',3'-dideoxythymidine to patients with AIDS-related neurological disease.

3'-Azido-2',3'-dideoxythymidine (AZT) has been administered to 7 patients with human immunodeficiency virus-associated neurological disease: 3 with dementia, 2 with peripheral neuropathy, 1 with dementia and peripheral neuropathy, and 1 with T-10 paraplegia. Six of the patients showed improvement in their neurological dysfunction on being administered AZT, as assessed by clinical evaluation, neuropsychological testing, nerve conduction studies, and/or positron emission tomographic scans. Three of these 6 patients showed sustained improvement 5 to 18 months after the initiation of AZT therapy. These results suggest that certain human immunodeficiency virus-associated neurological abnormalities are at least partially reversible following the administration of antiretroviral therapy and provide a rationale for further studies using antiretroviral chemotherapy.

Response of human-immunodeficiency-virus-associated neurological disease to 3'-azido-3'-deoxythymidine.

Four patients with human-immuno-deficiency-virus-associated neurological disease were treated with 3'-azido-3'-deoxythymidine (AZT). Three (two with chronic dementia, and one with chronic dementia and peripheral neuropathy) improved as assessed by clinical examination, psychometric tests, nerve conduction studies, and/or positron emission tomography; there was no improvement in the fourth patient who presented with paraplegia. These results support the hypothesis that certain AIDS-virus-associated neurological abnormalities are reversible by antiretroviral chemotherapy.