Three types of fertility control, surgical sterilization, hormonal chemosterilization, and immunosterilization, are reviewed with regard to their potential for controlling problematic populations of carnivores. The fertility control agent and delivery protocol of choice may vary considerably according to: (i) the reason for control; (ii) the degree, urgency and duration of population reduction required; (iii) concerns about ethics and public opinion; and (iv) the status, population dynamics, social structure, mating system, size, behaviour and reproductive endocrinology of the target animals. Although they are often perceived and advocated as more preferable methods of population control than lethal approaches, it is important that wildlife managers as well as members of the public realize that the ethical acceptability of the various fertility control techniques may differ considerably - and that numerous questions regarding their effectiveness, humaneness and ecological safety remain unanswered.

The welfare of transported pigs can be compromised both by physical and psychological stresses. The animals’ responses can be assessed using records of mortality and trauma, physiological and behavioural observations and, to some degree, by measurements of meat quality since this can reflect the animals' physiological state at death. These assessments may, therefore, be used as measures of animal welfare. During transport pigs show weight loss, increased circulating concentrations of catecholamines, Cortisol and creatine phosphokinase (CPK), and an increase in heart rate and packed cell volume; sometimes there is evidence of dehydration. Increased levels of dark, firm, dry (DFD)meat after long transport reflect muscle glycogen depletion and possibly indicate some element of fatigue. There is experimental evidence that transport is aversive to pigs, which may be partially due to the fact that they become travel sick. Mortality in transport has ranged from < 0.1 to > 1.0 per cent in different European countries. Mortality is higher in more stress-susceptible breeds and at higher ambient temperatures. It is increased in pigs fed within 4h of transport, at higher stocking densities and after longer journeys at ambient temperatures greater than 10°C. Pigs may be fasted long enough before slaughter to prejudice their welfare through hunger. Long fasts may also reduce muscle glycogen levels and cause fatigue. Fighting between unfamiliar animals which have been mixed during the marketing procedure is also stressful, however, longer transport may actually reduce this problem by allowing animals to get used to one another under conditions in which it is difficult to fight.

In hedonic theories of motivation, ‘motivational affective states’ (MASs) are typically seen as adaptations which motivate certain types of behaviour, especially in situations where a flexible or learned response is more adaptive than a rigid or reflexive one. MASs can be negative (eg unpleasant feelings of hunger or pain) or positive (eg pleasant feelings associated with eating and playing). Hedonic theories often portray negative and positive MASs as opposite ends of a one-dimensional scale.

We suggest that natural selection has favoured negative and positive affect as separate processes to solve two different types of motivational problems. We propose that negative MASs (eg thirst, fear) evolved in response to ‘need situations’ where the fitness benefit of an action has increased, often because the action is needed to cope with a threat to survival or reproductive success. We propose that these negative MASs develop in response to a change in the body (eg dehydration) or the environment (eg the approach of a predator) which creates the need for action, and that negative MASs can become intense and prolonged if the threat to fitness is high and persistent. We propose that positive MASs evolved in ‘opportunity situations ‘ where an action (eg playing, exploring) has become advantageous because the fitness cost of performing it has declined. We propose that these positive MASs occur during, or as a result of, the performance of types of behaviour which are beneficial for fitness at a variety of times, not only when they are required to meet immediate needs; and that the pleasure inherent in the behaviour motivates the animal to perform it when the cost of so doing is sufficiently low. Some behaviour (eg eating) can be motivated by both positive and negative affect. Other behaviour, such as playing or fleeing from a predator, may be motivated largely by positive or negative affect alone. Our hypothesis needs to be tested, but we suggest that it corresponds well to common human experience.

The hypothesis provides a basis for predicting whether an aspect of animal management is likely to cause strong and prolonged negative affect (‘suffering’), or to prevent animals from experiencing certain types of pleasure. This distinction is important for bringing animal welfare assessment into line with ethical concerns.

The welfare of farm animals is strongly influenced by the man-made environment. Welfare problems also arise from reduced homeostatic capacities in animals. Feed additives, used to promote growth or to prevent diseases can alter the animals' self-regulating capacities thus affecting their welfare. The EU regulates the use of these additives within specified groups of Directive 70/524/EEC. Although these feed additives can be regarded as prescription-free veterinary drugs, critical remarks on their desired and adverse effects have received little attention.

A survey of the available literature shows that about one-third of licensed feed additives alter adrenal function in vitro. Reports of the adverse effects of anticoccidial additives in vivo suggest they can be classified under three headings: (i) substances with a very narrow safety margin (the difference between the permitted dose and the dose with adverse effects) and often irreversible effects on growth and feed conversion; (ii) substances with a narrow safety margin and largely reversible effects; (iii) substances with an adequate safety margin. The growth promoters (including antibiotic growth promoters) can - on the basis of their adverse effects - be classified into two groups: (i) substances with a very narrow safety margin; and (ii) substances with an adequate safety margin.

On the one hand, animal welfare considerations require use of disease-preventing additives, but on the other hand, they also demand discontinuation of current practices. Judicious use of additives can add to animal welfare. However, their unlimited use to obscure defects in husbandry is detrimental to animal welfare. A major obstacle to the judicious use of feed additives, is the lack of published, unbiased information on their efficacy and safety for farm animals.

Many of Australia's nocturnal mammals are rare or endangered in the wild. The behavioural integrity of captive populations of endangered species can be maintained through the application of environmental enrichment techniques. This study investigated the effectiveness of feeding enrichment in promoting behavioural diversity, enclosure usage and species-typical behaviours in the ghost bat (Macroderma gigas) and the yellow-bellied glider (Petaurus australis). Animals were observed for 300 min day-1 over three consecutive time periods: baseline (12 non-consecutive days); enrichment: (12 consecutive days); and post-enrichment: (12 non-consecutive days). The use of a live insect dispenser decreased grooming and increased out-of-sight and social behaviour in the ghost bat. Artificial gum trees promoted species-typical behaviours in the yellow-bellied glider. Enrichment for nocturnal mammals had variable results and different welfare implications for these animals.

This study (1978-93) was concerned with calf site selection by red deer from three contrasting areas (two deer parks and one deer farm) of north-west England. It arose from initial (1960s-70s) concern over poor recruitment and the high incidence of ‘abandoned’ calves (at one site), and increasing levels of public disturbance in Lyme Park and Tatton Park. A better understanding of calving behaviour could lead to improved management procedures during calving. Habitat selection by adult females was examined indirectly, by recording where calves (0-2 days old) were born in relation to their weight. The deer farm provided a control site, where the effects of their social traditions could be minimized.

Calves were born over a wide area of moorland in Lyme Park but confined to a deer sanctuary in Tatton Park. Areas of obvious plant cover were selected in preference to open ground in Tatton Park and in the deer farm. No marked preferences were apparent in Lyme Park, although some areas were used more frequently than others, over all years. Most calves occurred within female home ranges. In Tatton Park, the heaviest calves were found in the preferred calving sites.

Calf weights varied widely within and between study sites. On average, the smallest (lightest) calves were recorded in Lyme Park and the heaviest in the deer farm. Sex differences in calf weights occurred in Tatton Park, but not at the other two sites. In general, late-born calves were smaller than those born early in the season. Variations in birthweight were linked to differences in female growth and site conditions. In the absence of more detailed statistics, calf weights can provide a useful measure of population performance.

Collectively, these results suggest that red deer can adopt a range of calving behaviours (‘tactics’) depending on the nature of the habitat (presence or absence of cover), perceived predation ‘risks’ (levels of disturbance), established social traditions and, possibly, parental investment. Cover appeared to be a primary requirement for calving. In the absence of cover, other behaviours were adopted. In some cases, these behaviours were not in the best interests of the calf, asparent females rarely returned tofeed their calves during the day and often engaged in energetically costly diversionary activities. In deer farms, conflicts between hinds may be exaggerated by limited access to ground cover, similar social status and low variance in calf weights.

In view of thesefindings, there is a need to devise new ways of attracting captive deer to cover, perhaps by modifications to the habitat mosaic. Observations from Tafton Park show that deer readily use refuges (the sanctuary), when available, although it may be difficult to initiate new behaviours where long-established traditions occur (eg Lyme Park). Mortality amongst calves is unacceptable in deer parks, but further work under more controlled conditions, is required to establish the mechanisms of calf site selection. Effective methods of locating calves are desirable for management purposes.

This paper presents the report of a LASA workshop on developing the ethics component of the UK modular training system for laboratory animal scientists. The objectives were: (i) to define and agree the goals of ethics training; ii) to set out means of achieving these goals in terms of an appropriate syllabus, effective approaches to training, and the resources necessary; (iii) to define the audience - who should be trained and to what level; and iv) to consider the practicalities and means of assessment of prospective licensees. Although the focus was on the UK system, the issues are similar wherever ethics is taught in the laboratory animal context.

A keynote paper introduced the subjects for discussion and four course organizers then provided examples of current practice. Syndicate group sessions addressed questions in relation to the goals enumerated above. This report represents a summary of the papers, syndicate group discussions and conclusions of the workshop.