The conditions under which laying hens are kept remain a major animal welfare concern. It is one of the most intensive forms of animal production and the number of animals involved is very high. Widespread public debate has stimulated the call for more animal friendly, alternative systems to barren conventional cages. Directive 1999/74/EC has encouraged technical changes in current systems. Not only have traditional cages been modified (so-called 'enriched cages'), but also new alternative systems (e.g. aviaries) have been developed. There is an ongoing need to evaluate the actual welfare status of hens in these novel systems including those on commercial farms. The LayWel project, was funded via the European Commission's Sixth Framework Programme and national funding from several EU countries. Its general objective was to produce an evaluation of the welfare of laying hens in various systems, with special focus on enriched cages, and to disseminate the information in all member states of the EU and associated countries. The project took into account pathological, zootechnical, physiological and ethological aspects.A major achievement of the LayWel project was the compilation of a database collecting data from different housing systems and thus enabling data comparison. The project partners recommend that support is given to maintaining the database in the future so that data can be more reliably modelled. As the type of data collected did not often allow a formal statistical analysis the evaluation of welfare was a presentation of risk factors and advantages and disadvantages of various housing systems. Conclusions are that, with the exception of conventional cages, all systems have the potential to provide satisfactory welfare for laying hens. However this potential is not always realised in practice. Among the numerous explanations are management, climate, design, different responses by different genotypes and interacting effects. A second major achievement of the project was the development of feather scoring and integument (skin, head and feet) scoring systems together with comprehensive sets of photographs. It is recommended that the integument scoring systems are widely adopted and used in on-going research. Farms should also routinely and frequently carry out integument scoring to assist in the detection of damaging pecking, which is currently a widespread welfare problem. Within LayWel an on-farm auditing procedure was developed in the form of a manual for self-assessment. The manual first explains what is meant by welfare and outlines the relevance of welfare assessment. It also summarises risks to welfare in the main categories of housing system. The second part contains recording forms, with guidance for assessing hen welfare. These enable regular checks of a range of indicators of laying hen welfare to be carried out systematically. The indicators were chosen to be relevant to hen welfare as well as feasible and reliable to apply in practice. A series of conclusions and recommendations were made on v...

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. 1994. Validation of a heart-rate monitor for measuring a stress response in dairy cows.Can. J. Anim. Sci.,.In three experiments, a commercial non-invasive heart-rate monitor, Polar@ Sport Tester (PST), was validated for use with dairy cows. First, l0 monitors were tested using a pulse generator, which produced pulses at levels between 30 and240 bpm. PST values and generated beats were highly correlated (r : 0.97) but with varying delay (5-55 s), depending on pulse-rate level.In a second experiment, 10 dairy cows were quietly standing or exercising on a treadmill while their heart rates were recorded by direct-wire electrocardiograph (ECG) as well as the PST. Correlations between ECG and PST values during standing (0.88) and exercising (0.72) were significant and differed between cows. During standing, inter-beat interval and PST standard deviations were significantly correlated (R." : 0.76), as were their coefficients of variation (R,o : 0.89).The third experiment showed that the heart rate of 10 dairy cows increased rapidly immediately after an individual was isolated from the herd. Cows showed no obvious signs of being hampered by the equipment during the l-h trials.Change in heart rate may be a relevant parameter for studying an animal's response to a stressor. As heart-rate variability is thought to serve as an important mechanism for adaptability in humans, this aspect needs further attention in farm animals. The PST is suitable for measuring both heart rate and heart-rate variability in dairy cows.Key words: Heart rate, dairy cows, stress, treadmill

An experiment was performed in primiparous dairy cows (n = 23) to examine consistency of individual differences in reactivity to milking, and correlations between measures of behavior, physiology, and milk ejection. Responsiveness to milking was monitored during the first machine milking, on d 2 of lactation, and during milkings on d 4 and 130 of lactation. Measurements included kicking and stepping behavior, plasma cortisol and plasma oxytocin, heart rate, milk yield, milking time, milk flow rate, and residual milk obtained after administration of exogenous oxytocin. With repeated early lactation milkings, residual milk and the incidence of abnormal milk flow curves decreased. On d 130 of lactation all heifers exhibited normal milk ejection. Except for higher plasma cortisol concentrations on d 2, all measures were consistent over time between d 2 and 4 of lactation as indicated by significant rank correlations. Individual differences in the behavioral response to udder preparation were consistent over time between early lactation milkings and d 130 of lactation. Residual milk, milk yield, maximum milk flow rate, plasma oxytocin and heart rate during udder preparation were similarly interrelated on d 2 and 4 of lactation. High heart rate responses on d 2 and 4 were associated with enhanced inhibition of milk ejection. In contrast, behavior recorded during the milking process was unrelated to ease of milk removal. Our results indicate that milking at the beginning of lactation may be stressful to some heifers, to the extent that milk ejection is inhibited, but less disturbing to others. The existence of consistent behavioral and physiological responses in the present study suggests that responsiveness of dairy heifers to milking is mediated by stable animal characteristics.

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