Cortisol response of female rhesus monkeys to venipuncture in homecage versus venipuncture in restraint apparatus

Cortisol response of ten single-caged adult female rhesus monkeys during venipuncture in a restraint apparatus was compared with cortisol response of ten paired and five single-caged adult female rhesus monkeys during venipuncture in the homecage. Results demonstrated that in-homecage venipuncture offers a methodological improvement for research protocols that require blood collection of undisturbed animals.     

Working with rather than against macaques during blood collection

Training macaques to cooperate during blood collection is a practicable and safe alternative to the traditional procedure implying forced restraint. It takes a cumulative total of about 1 hr to train an adult female or adult male rhesus macaque successfully to present a leg voluntarily and accept venipuncture in the homecage. Cooperative animals do not show the significant cortisol response and defensive reactions that typically occur in animals who are forcibly restrained during this common procedure.     

Designing mate choice experiments

The important role that mate choice plays in the lives of animals is matched by the large and active research field dedicated to studying it. Researchers work on a wide range of species and behaviours, and so the experimental approaches used to measure animal mate choice are highly variable. Importantly, these differences are often not purely cosmetic; they can strongly influence the measurement of choice, for example by varying the behaviour of animals during tests, the aspects of choice actually measured, and statistical power. Consideration of these effects are important when comparing results among studies using different types of test, or when using laboratory results to predict animal behaviour in natural populations. However, these effects have been underappreciated by the mate choice literature to date. I focus on five key experimental considerations that may influence choice: (i) should mating be allowed to occur, or should a proxy behavioural measure of preference be used instead? (ii) Should subjects be given a choice of options? (iii) Should each subject be tested more than once, either with the same or different stimuli? (iv) When given a choice, how many options should the subject choose between? (v) What form should the experimental stimuli take? I discuss the practical advantages and disadvantages of common experimental approaches, and how they may influence the measurement of mate choice in systematic ways. Different approaches often influence the ability of animals to perceive and compare stimuli presented during tests, or the perceived costs and benefits of being choosy. Given that variation in the design of mate choice experiments is likely unavoidable, I emphasise that there is no single ‘correct’ approach to measuring choice across species, although ecological relevance is crucial if the aim is to understand how choice acts in natural populations. I also highlight the need for quantitative estimates of the sizes of potentially important effects, without which we cannot make informed design decisions.     

Imitative behavior. A theoretical view

This article reviews the results of experimental studies on imitative behavior reported by various investigators, and then discusses the possible brain mechanisms responsible for this behavior. It was found that human infants in their first hours of life were already capable of spontaneous imitation of simple motor acts demonstrated by an adult, without previous training or reward; these observations suggest that imitative behavior is an innate process that can be considered an unconditional reflex of imitation. It was also found that satiated animals resumed eating when they saw their companions eating. In the latter case, the imitative reflex triggered the previously acquired feeding behavior. Similar mechanisms could be responsible for the phenomenon of eating more in the presence of companions than in their absence, as well as that of preferring the food chosen by companions. When followed by a reward, the imitative act can be learned--that is, transformed into an instrumental conditional response; learning by imitation of simple motor acts was observed in animals, and that of complex motor acts was observed in children who had already achieved a certain developmental stage. In animals, learning complex motor tasks was facilitated by previous observation of a companion performing this task. In this case, the presence of the observer during the session could lead to habituation of the experimental situation and production of associations between this situation and stimuli or emotions related to the reward or punishment, and might result in more efficient learning later. The imitative behavior can be inhibited by stimuli producing responses antagonistic to the act of imitation.     

Is the yak (Poephagus grunniens L.) really a seasonal breeder?

Yaks are considered to be seasonally polyestrous and breeding occurs from July to November. Here we show that some yaks in peak non-breeding season do exhibit cyclic luteal activity without exhibiting any behavioral signs around expected estrus. A total of eight non-lactating yaks were selected from the Yak Farm belonging to National Research Centre on Yak for various sets of experiments. The animals were maintained as per semi range system of management. They were allowed to graze during daytime and fed concentrate mixture @2 kg/animal/day as per standard farm practices of the center. Blood samples were collected on alternate days for 30 days by jugular venipuncture from the yaks during peak breeding season (July to November) and from the same yaks in non-breeding season (February to March). The plasma samples were analysed for progesterone and estradiol-17beta by RIA and EIA procedures, respectively. During breeding season, the mean plasma progesterone at estrus was basal (相似文献   

Habitat‐mediated timing of migration in polar bears: an individual perspective

Migration phenology is largely determined by how animals respond to seasonal changes in environmental conditions. Our perception of the relationship between migratory behavior and environmental cues can vary depending on the spatial scale at which these interactions are measured. Understanding the behavioral mechanisms behind population‐scale movements requires knowledge of how individuals respond to local cues. We show how time‐to‐event models can be used to predict what factors are associated with the timing of an individual's migratory behavior using data from GPS collared polar bears (Ursus maritimus) that move seasonally between sea ice and terrestrial habitats. We found the concentration of sea ice that bears experience at a local level, along with the duration of exposure to these conditions, was most associated with individual migration timing. Our results corroborate studies that assume thresholds of >50% sea ice concentration are necessary for suitable polar bear habitat; however, continued periods (e.g., days to weeks) of exposure to suboptimal ice concentrations during seasonal melting were required before the proportion of bears migrating to land increased substantially. Time‐to‐event models are advantageous for examining individual movement patterns because they account for the idea that animals make decisions based on an accumulation of knowledge from the landscapes they move through and not simply the environment they are exposed to at the time of a decision. Understanding the migration behavior of polar bears moving between terrestrial and marine habitat, at multiple spatiotemporal scales, will be a major aspect of quantifying observed and potential demographic responses to climate‐induced environmental changes.     

Recommendations for improving the home office project licence abstracts

The Freedom of Information Act 2000 prompted the Government to evaluate how public understanding about the use of animals in scientific research can be improved and how animal experimentation is regulated within the UK. This resulted in the publication of anonymous project licence abstracts. Here, the abstracts published between December 2004 and October 2005 have been evaluated, by using a scoring system which takes into account their content and format, in order to assess whether they provide information that will facilitate the increased implementation of reduction, refinement and replacement strategies. The potential impact of freely-available Home Office project licence abstracts on public attitudes to animal testing and on the quality of animal-based research, is also discussed. Although some abstracts scored well, in general, the abstracts were found to be severely lacking in detail about the welfare of experimental animals. Thus, the abstracts tend to present a distorted picture of animal-based research. Many abstracts lack the details which would reveal how the licensing criteria had been met. It is concluded that, in their current form, the project abstracts are not sufficiently informative. A number of recommendations are made, which address this problem.     

Electroencephalographic effects of thiopentone and its enantiomers in the rat

Electrophysiological studies with some chiral barbiturates have shown that one enantiomer can be excitant while the other is depressant. Thiopentone, a chiral barbiturate, has both differences in potency between enantiomers and biphasic effects on the electroencephalogram (EEG). This study investigated whether a differential EEG activity between the enantiomers of thiopentone could account for the biphasic effects. Rats were administered rac-, R- or S-thiopentone to determine the nature and time course of quantitative EEG effects. Two studies using computer-controlled i.v. infusions of the three drugs were performed in groups of animals previously prepared with EEG electrodes and/or arterial blood sampling cannulae. Study 1 used several stepwise increments in plasma drug concentration over 35 min, followed by washout. Study 2 used a 4 min period of constant plasma drug concentration, followed by washout. In both studies, both enantiomers and racemate caused an initial EEG activation followed by deactivation. Quantitative enantioselectivity was found for depression. The extent of depression was significantly less for R-thiopentone (P=0.008) and racthiopentone (P=0.038) than for S-thiopentone; recovery from depression appeared to be faster for R-thiopentone than either rac- or S-thiopentone. Fatality was only found with S-thiopentone (3/7 animals in Study 2). R-thiopentone plasma concentrations were approximately 8% less than those of S-thiopentone in rats treated with racthiopentone. Although small differences in clearance between enantiomers were found that may influence recovery, they were not large enough to account for the reported differences in potency between the two enantiomers.     

Separation of and cholesterol synthesis by human lymphocytes and monocytes.

We have devised techniques for the isolation of human monocytes which do not require the adherence of the cells to a surface. In 15 consecutive experiments using density-gradient and counterflow centrifugations, a population of mononuclear cells that was 75 +/- 11% monocytes was obtained within 2 hours of venipuncture. These cells had never been pelleted and represented approximately three-fourths of the monocytes that had been present in the whole blood. In another 22 consecutive experiments using sedimentation in gelatin followed by counterflow and density-gradient centrifugations, a population of lymphocytes that was 99.5 +/- 0.5% pure and a population of monocytes that was 94 +/- 3% pure were obtained within 3 hours of venipuncture. When these freshly isolated cells were incubated in the lipoprotein-deficient fraction of serum (d > 1.21 g/ml) or in solvent-extracted serum, the monocytes incorporated 10-20 times more [2-(14)C]acetate into sterols than did the lymphocytes. Monocytes were seen to constitute between 6 and 46% of the mononuclear cells isolated from normal individuals by the usual density-gradient centrifugation of whole blood on Ficoll-Hypaque. We conclude that future studies of cholesterol metabolism utilizing human mononuclear cells must take into account this large variation in the percentage of monocytes and their disproportionately greater activity during short-term incubations in media that induce sterol synthesis.-Fogelman, A. M., J. Seager, M. Hokom, and P. A. Edwards. Separation of and cholesterol synthesis by human lymphocytes and monocytes.     

Antioxidative activity of lipids in mice during aging and administration of an antioxidant with gerontological protective action

Changes in the antioxidative activity (AOA) of the liver were studied during natural aging in noninbred and C3HA mice and during administration of the synthetic anti-oxidant 2-ethyl-6-methyl-3-hydroxypyridine hydroxypyridine hydrochloride to the animals, and the effect of the doses of this compound on the level of AOA in the liver of animals aged 2 months also was investigated. Liver AOA in mice was found to decrease during aging; the decreae in animals with tumors was found to be two or three times slower than in animals without tumors. Administration of the compound after the age of 8 months led to a considerable increase in liver AOA, and this may evidently account for the considerable lengthening of the life of the experimental animals.     

Homeostatic regulation of sleep in arrhythmic Siberian hamsters

Sleep is regulated by independent yet interacting circadian and homeostatic processes. The present study used a novel approach to study sleep homeostasis in the absence of circadian influences by exposing Siberian hamsters to a simple phase delay of the photocycle to make them arrhythmic. Because these hamsters lacked any circadian organization, their sleep homeostasis could be studied in the absence of circadian interactions. Control animals retained circadian rhythmicity after the phase shift and re-entrained to the phase-shifted photocycle. These animals displayed robust daily sleep-wake rhythms with consolidated sleep during the light phase beginning about 1 h after light onset. This marked sleep-wake pattern was circadian in that it persisted in constant darkness. The distribution of sleep in the arrhythmic hamsters over 24 h was similar to that in the light phase of rhythmic animals. Therefore, daily sleep amounts were higher in arrhythmic animals compared with rhythmic ones. During 2- and 6-h sleep deprivations (SD), it was more difficult to keep arrhythmic hamsters awake than it was for rhythmic hamsters. Because the arrhythmic animals obtained more non-rapid eye movement sleep (NREMS) during the SD, they showed a diminished compensatory response in NREMS EEG slow-wave activity during recovery sleep. When amounts of sleep during the SD were taken into account, there were no differences in sleep homeostasis between experimental and control hamsters. Thus loss of circadian control did not alter the homeostatic response to SD. This supports the view that circadian and homeostatic influences on sleep regulation are independent processes.     

Chronic central vein catheterization for intraoperative and long-term venous access in swine

Chronic venous access and repeated blood sampling for research purposes in large swine ideally should be possible without sedation, restraint or direct venipuncture of deep vessels. An operative technique of cranial vena cava catheterization and chronic catheter maintenance methods are described which were used successfully in the placement of 11 silicone rubber catheters in 10 animals. All were used for repeated blood sampling, as well as intraoperative infusion of medications and large fluid volumes. Long term patency was excellent with 10 catheters patent at the end of the study interval, up to 14 weeks after insertion. Serial blood sampling was accomplished easily without restraint. Catheter damage, infection or malfunction was rare. Proper maintenance and careful aseptic blood sampling render the cranial vena cava catheter a safe and reliable alternative to direct venipuncture in swine.     

Limited Company

ABSTRACT

This paper looks at the attitudes that scientists hold toward their use of animals, and at some implications for the welfare of laboratory animals. The framework for this analysis is recent changes in the law regulating the use of animals in British science. We note how ambivalent many scientists are about the way they perceive the animals they use, and the moral dilemmas such use poses. We argue, however, that the legislation itself cannot mediate improvements in animal welfare, as it is inevitably policed by the scientific community itself and thus dependent upon values and social relationships within science. We also argue that debates about the promotion of lab animals' welfare tend to use the distancing stance of science; they focus on scientific studies of welfare and behavior, but ignore the context. An important part of that context is the relationships between humans and animals in the lab, which should be taken into account more fully if animals are to benefit.     

Spatial inference without a cognitive map: the role of higher-order path integration

The cognitive map has been taken as the standard model for how agents infer the most efficient route to a goal location. Alternatively, path integration – maintaining a homing vector during navigation – constitutes a primitive and presumably less-flexible strategy than cognitive mapping because path integration relies primarily on vestibular stimuli and pace counting. The historical debate as to whether complex spatial navigation is ruled by associative learning or cognitive map mechanisms has been challenged by experimental difficulties in successfully neutralizing path integration. To our knowledge, there are only three studies that have succeeded in resolving this issue, all showing clear evidence of novel route taking, a behaviour outside the scope of traditional associative learning accounts. Nevertheless, there is no mechanistic explanation as to how animals perform novel route taking. We propose here a new model of spatial learning that combines path integration with higher-order associative learning, and demonstrate how it can account for novel route taking without a cognitive map, thus resolving this long-standing debate. We show how our higher-order path integration (HOPI) model can explain spatial inferences, such as novel detours and shortcuts. Our analysis suggests that a phylogenetically ancient, vector-based navigational strategy utilizing associative processes is powerful enough to support complex spatial inferences.     

THE UTILIZATION OF NATURAL PASTURES BY WILD ANIMALS IN THE RUKWA VALLEY, TANGANYIKA

The object of this paper is to elucidate the principles involved in the utilization of natural grasslands by an indigenous community of animals. The studies were carried out in the Rukwa valley during a period of fourteen years and it is suggested that the results are applicable to other similar ecological areas.
The various types of grassland and pasture which occur are described, and their ecology and seasonal development are discussed in relation to the climate and drainage in the valley. The incidence of fire is recorded and its influence is compared with the effects of grazing.
The utilization of the pastures by herbivorous animals is described, and it is explained how grazing pressure results in pasture rejuvenation which is manifest by the development of a grazing mosaic. It is shown that a sequence of animals, heavier ones followed by lighter ones, use the different pastures in rotation during the year and as a consequence alternate periods of optimum use and rest occur, and the harmful effects of over-grazing do not appear.
The species of animals which form the Rukwa valley grazing community are listed and the ecological stresses which they experience in a changeable environment are noted. Examples are quoted to support the view that dry periods favour the fauna whereas extremely wet ones are unfavourable. It is shown how the ability of the animals to establish biotic pressure on the pastures enables them to become rehabilitated even though conditions remain unfavourable.
It is opined that if the same principles are made use of in game management schemes elsewhere, successful conservation of both grasslands and animals is likely to be achieved.     

Urea production and accumulation in the green toad, Bufo viridis

The toad, Bufo viridis , can live for several months without access to free water, absorbing soil-bound water down a water-potential gradient created, mainly, by accumulating urea in its body fluids. We investigated if the retention of urine was sufficient to account for the rate of accumulation or if an increased rate of urea production was needed in order to do so. The basal rate of urea production in unfed animals in the absence of osmotic stress was estimated by two methods; first, analysis of the bathing medium and, secondly, collection and analysis of urine at two-hourly intervals. This was then repeated with animals fed a weight-maintaining diet. Generally similar results were obtained by either method in both fed and unfed animals, although higher urea production rates were found in the former. Although it had been planned to apply the short interval method to toads with free access to water, the control condition for toads transferred to soil, it proved to be impracticable. Some animals did not bathe for almost a day, during which time minute quantities of urine were obtained. Larger volumes were only produced during or after bathing. Consequently, animals which were partially immersed in water were substituted as controls. Total urea content was determined in these and in toads after a week on soil. The calculated increase was compared to that which could be expected from urine retention. It was found that urea accumulated at more than twice the predicted rate. When rates of accumulation were calculated over longer periods, urine retention alone was sufficient to account for them within three weeks on soil, the usual period required for acclimation. We concluded that B. viridis increased its rate of urea production only for a short period, until a favourable water potential gradient was achieved.     

An improved method for repeated plasmapheresis in the rat.

An improved method for plasmapheresis in the rat was designed. The rat was anesthetized with ketamine hydrochloride, and venipuncture of the iliac vein was performed with a 21-ga butterfly infusion set with 12' of flexible tubing. Six ml of blood were drawn into a heparinized syringe and centrifugated. After the plasma was separated, the rbc were reinfused through the phlebotomy apparatus. This procedure was performed on each rat weekly for 10 wk without apparent harm to the animals. There were no changes in total serum protein and albumin, and body weights in most animals remained constant. This method should prove valuable in studies in which long-term plasmapheresis is indicated.     

小型哺乳动物种群周期性波动的自我调节假说

种群调节是种群生态学的一个核心问题。文章主要阐述了小型哺乳动物种群在其低数量期自我调节的4 种可能假说和相关的实验证据。其中, 有关衰老—母体效应假说近年已受到普遍重视, 而支持多态行为假说、社会生物学假说和远交假说的证据较少, 尚需更多的实验来加以验证。衰老—母体效应假说是在应激假说的基础上发展而成的。该假说认为, 母体质量会在整个高峰期的动物中发生改变, 并能够延续到衰减期和低数量期。在低数量期, 种群内的老年个体增多, 导致它们不能维持内分泌的自稳态, 可能通过影响后代的存活和生殖而维持低数量, 进而起到调节种群周期的作用。针对国际上研究的发展趋势, 我们还对未来的研究方向提出了一些建议。     

Legal and ethical aspects of new wildlife food sources

The production of animals for new sources of food may be affected by a variety of laws relating to the keeping, trading, health, welfare and movement of animals. Other legislation, such as that applicable to wildlife and to human safety, are also relevant. Religious, cultural and ethical considerations may also influence attitudes towards a new food product. It is important that these factors are taken into account during the planning and progress of an enterprise since they may have a substantial impact on its viability.     

3R和替代方法是否进行了有效的探究（英文）

Although the publication of peer-reviewed scientific papers is the major way in which scientists communicate with one another,these papers often lack essential information about the conditions under which the animals lived and how they were treated during the experiments.Without this information it may be impossible to evaluate the studies,replicate them in another laboratory,or use them to advance the 3Rs in other animal experiments.This paper gives some advice on how the reporting of animal research can be improved.