Male African cichlids (Oreochromis mossambicus) establish territories on the substrate upon which spawning pits are dug, thus attracting females. The substrate, therefore, plays a very significant role in its lifecycle. The effects of substrate access on behaviour and physiology in captivity were assessed. Mixed-sex, all-male and all-female groups were observed for five days, with and without substrate. Social patterns, behaviour directed towards the substrate, locomotor activity and spatial behaviour were recorded, and haematocrit, plasma cortisol and glucose levels were measured. Substrate inclusion saw a significant increase in behavioural diversity, sexual behaviour of dominant males in mixed groups, pit digging and territoriality whereas a lack of substrate was characterised by increased chafing and inactivity. Vacuum-pit digging was also observed. Frequency of aggression did not differ significantly and female behaviour was not affected by the presence of substrate. For both sexes, no differences in cortisol and glucose levels were found between the two treatments, but haematocrit increased with substrate. The key role played by substrate in territorial males is consistent with the behavioural and physiological data reported. In the absence of substrate, decreased territorial behaviour is contrasted with similar levels of aggression, cortisol and glucose; all of which are suggestive of a stress-related context. Moreover, the exhibition of vacuum activities is a signal that behavioural needs are not being met and may be some form of coping mechanism. These findings, taken in conjunction with the variations in behavioural diversity and inactivity, suggest that the welfare of male cichlids may be adversely affected by the absence of substrate.

Mammals are unique among vertebrates in experiencing a need to carry out behaviours which are not necessary for their immediate survival. This poses questions as to the nature of these behavioural needs, how they evolved and their implications for the welfare of mammals in captivity. Evidence is provided to show that mammals carry out daily programmes of activity which meet four kinds of requirement, namely, for security, appropriate environmental complexity, novelty and opportunities for achievement. Within their programmes mammals perform two kinds of activity: work, which relates to day to day survival, and leisure, in the form of curiosity or play, which provides experience which may prove to be of value in the long term.

The existence of behavioural needs is consistent with our knowledge of mammalian evolution. Even the earliest known mammals, living over 120 million years ago, differed from reptiles in having brain to body size ratios four to five times greater. The increase in brain size resulted largely from the massive expansion of a region of the cerebral cortex, known as the neopallium, which acts as a co-ordinating centre for sensory data, and creates a model of the world which determines subsequent action. During the 60 million year tertiary era, relative brain size increased in most orders of eutherian mammals, so that only the more intelligent survived.

Because mammals rely for their survival on collecting and analyzing data and acting intelligently, they need facilities to search for information to establish and monitor their concept of the real world; their psychological well-being depends on an environment which offers such facilities. There are two kinds of behavioural needs; psychological needs, which appear to be unique to mammals, and ethological needs which are experienced by all vertebrates. It is concluded that environmental quality for captive mammals should not just be assessed negatively, by the absence of abnormal behaviours, but more positively by the extent to which it meets their psychological needs.

Commercial pigs kept outdoors are often given nose-rings, to inhibit rooting and minimize pasture damage. If rooting is a ‘behavioural need’ in the pig, and ringing is effective because it renders rooting painful, nose-ringing may be a threat to welfare. Thirty gestating sows were assigned to one of three conditions: unringed controls (UR); sows ringed with three, wire ‘clip’ rings through the snout rim (CR); or sows with one, rigid ‘bull’ ring (BR). They were observed on grass for 7h day−1 at intervals over 6 months. Ringing almost totally abolished penetration of the ground by rooting during the month after ringing (UR, CR and BR sows respectively spent 5.6%, 0.1% and 0.1 % of scan observations dig-rooting during this month; P < 0.001). These differences in recorded rooting were reflected in a much greater extent of pasture damage in paddocks containing UR sows. Rooting remained largely suppressed throughout the 6 months of observations in BR sows; but substantial recovery of this function occurred in CR sows by the sixth month, although much of this may be attributed to the fact that most sows lost at least some of their rings. Ringing also partially inhibited grazing (which accounted for 26.2%, 27.1% and 21.9 % of scans over the whole project in UR, CR and BR sows respectively; P < 0.05), nosing in straw, digging out wallows and stone-chewing (18.3%, 9.5% and 9.2% respectively of all scans in UR, CR and BR sows; P < 0.001). Ringed sows spent more time standing but otherwise inactive than did controls (0.8%, 1.7% and 4.0% of all scans in UR, CR and BR sows respectively; P < 0 .001), and displayed more straw-chewing, vacuum-chewing and digging at soil with the forepaw. We conclude that nose-ringing in pigs inhibited a range of functional activities, as well as rooting, and elicited more behaviours that suggest a degree of reduced welfare. BR sows displayed more of these effects than did CR ones, although these differences may be largely, but not entirely, due to a loss of clip rings over time.

In recent years, consumer demand studies have been used to objectively quantify the value that captive animals place on environmental resources. Considerable progress has been made in the development of effective methodologies to assess what resources are valued under controlled experimental conditions, but few of the findings from these studies have been implemented in commercial husbandry systems. A major obstacle has been the need to maintain internal validity in experimental studies at the possible expense of external validity. Experimental subjects may be poor representatives of commercially kept animals, especially where there is no replication of the animal's experience of commercial physical and social environments. This paper will discuss means of increasing the external validity of consumer demand studies. Firstly, experimental animals should be of representative genotypes, reared under commercial conditions and housed in test apparatus with free access to all of the resources that are normally available under commercial husbandry conditions. As well as providing a long-term closed economy, this allows manipulation of potentially important environmental factors such as prior experience. Secondly, naturalistic tasks should, where possible, be used in preference to abstract operant tasks since they appear to be easier to train animals to associate with rewarding resources, therefore many individuals can be investigated efficiently. Furthermore, naturalistic tasks appear to be less prone to operant bias than artificial tasks and can provide robust measures of value in terms of the maximum price paid for access to resources. Finally, for group-housed species, social costs such as enduring higher stocking densities and/or competition for resources may be an effective means of investigating cost-benefit trade-offs under commercial conditions. For example, if animals work to evenly distribute themselves over available space, this social spacing priority can be used to investigate whether they will endure higher stocking densities in order to exploit particular resources.

It is commonly assumed that animals suffer if they cannot perform behaviours seen in wild conspecifics. Although comparisons with the behaviour of wild conspecifics are a popular method of assessing the welfare of captive animals, their validity has not been fully assessed. Homeostatic models of motivation suggest that many behaviours are stimulus driven rather than internally generated. Thus, it is possible that the non-performance of some wild-type behaviours does not necessarily compromise animal welfare, unless welfare is defined as being compromised by such non-performance. The flexibility of wild animal behaviour and the fact that animals free to perform the complete range of wild behaviours can suffer, must also put into the question the validity of such comparisons. Technical criticisms also arise when one considers the difficulty of constructing accurate and unbiased time budgets for wild animals. It is possible that the expressions of wild-type behaviours correlate with enhanced welfare, rather than cause enhanced welfare. Thus, if the consequences of behaviour are more important than the expression of behaviour itself, environmental enrichment does not necessarily need to rely upon the performance of wild-type behaviours for the improvement of animal welfare. Therefore, although behavioural comparisons with wild animals can be considered as potentially useful indicators of behavioural differences, they cannot always be relied upon to give an objective assessment of animal welfare. To make an assessment of welfare, behavioural comparisons with wild animals should be used in conjunction with other techniques to demonstrate that the consequences of non-performance of wild behaviours results in impoverished welfare.

This paper discusses the ethical implications of applying the concept of behavioural needs to captive animals. This is done on the basis of analysing the scientific literature on farmed mink and their possible need for swimming. In the wild, American mink (Mustela vison) are semi-aquatic predators, lending initial support to the claim that captive mink with no access to adequate swimming facilities experience a thwarted behavioural need. Scientific studies show a disparate picture. Consumer-demand experiments, where the animals have been conditioned to work for environmental resources, consistently show that mink place high value on swimming water, whereas other studies indicate the opposite, which has led scientists to question whether this preference constitutes a genuine behavioural need. In this paper, we take a methodological turn and discuss whether the oft-used concept of behavioural needs provides the best possible account of what is indispensable to an animal. Seen from a more complex understanding of behavioural needs, we suggest that lack of swimming opportunities for farmed mink constitutes a welfare problem. Further, it is argued that the decision of which paradigm to use in research on animal needs has not only ethical consequences, but is in itself a value-based choice.

Numerous studies have shown that providing straw to pigs can reduce undesirable behaviours such as aggression, tail biting and stereotypy. The measurement of various neuromodulators can be helpful in assessing the development of positive behaviours and overall animal welfare. The oxytocin release is frequently linked to positive emotions and positive welfare. It has been suggested that oxytocin modulates the serotoninergic system. This study aims to investigate the potential effect of straw provision in pigs on peripheral levels of oxytocin and serotonin. In total, 18 mini-pigs were involved in an exploratory study conducted in two parallel groups, Enriched (n=10) and Control (n=8) groups. Pigs were divided by group and housed in pens of two individuals. Straw was provided continuously only in Enriched group and renewed each day for 2 weeks. Two blood samples were drawn from each animal 5 to 10 min before providing the straw, and 15 min after providing straw, during the 1st week, to analyse peripheral changes in oxytocin and serotonin before and after straw provision, and determine the existence of a putative short-term effect. The same procedure was carried out for Control group, without straw provision. Long-term effects of straw provision were also examined using blood samples drawn at the same hour from each animal in the 2nd and 3rd weeks. During this time, animals had the permanent possibility to explore the straw in Enriched group but not in Control group. At the end of each week, one animal-keeper completed two visual analogue scales for each mini-pig regarding the difficulty/ease to work with and handle it and its trust in humans. Results showed peripheral oxytocin increases in both groups after 2 weeks (P=0.02). Results did not demonstrate any effect of providing straw to allow exploratory behaviour on peripheral serotonin. Other results were not significant. This preliminary study explored the relationship between peripheral oxytocin and serotonin and the presence of straw that allow pigs to perform exploratory behaviour, suggesting that there was no relationship between them. Some future studies may include crossing oxytocin and serotonin with other parameters, such as behavioural measures, to obtain more information about the true state of the animal and any possible relationship with pig welfare.

We review the behavioural needs, priorities and preferences of laying hens for increased space, perching, nesting, foraging and dustbathing behaviour. Hens make full use of and may work to gain access to perches, however it is not yet known how perching ranks in comparison with otherbehaviours. Laying hens appearto have an instinctive need to perform pre-laying (nest-building) behaviour and have a strong preference for a discrete, enclosed nest site, for which they will work hard to gain access as oviposition approaches. Access to a nest site is a high-ranking priority for laying hens, preferred over food at this time. Foraging is a behavioural need, with peat, sand and wood shavings preferred substrates in choice experiments. There is no reduction in time spent foraging when a cost is imposed, nor when feed is freely available. Dustbathing is currently viewed as a behavioural need, as the extent to which hens value dustbathing is not known. Bird preferences for space are complex and confounded by interactions between group size and stocking density. There is some evidence that priority for space varies during the day and increases when the total space available to a group of birds is restricted, and that greater priority is given to space than to small group size. The presence of apparently purposeless behaviour, of high levels of aggression or redirected behaviours such as feather pecking and cannibalism are indicators that the housing system is not meeting the behavioural needs of the hens and hence is not satisfactory forbird welfare.