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Ondanks aIle aandacht die het onderwerp dierenwelzijn recent krijgt zowel binnen de veterinaire beroepsgroep als in het rnaatschappelijke en politieke krachtenveld, blijft de vraag wat welzijn eigenlijk is, een onderwerp van discussie.

Emotion AI Emotion and Personality Synthesis technology is a solution to the problem of displaying expressive lifelike digital characters without the time and costs involved with traditional hand animation or motion capture. In addition these characters are fully interactive, being driven procedurally using various forms of pre processed input that are modulated through a system that simulates various neural pathways, neuro chemicals and neuro transmitters and finally models output through the various nerve pathways involved in facial expression and body posture muscle contractions.

Am J Vet Res. 2009 Jul;70(7):813-9. Use of epidurally derived evoked potentials for quantification of caudal nociception in ponies. van Loon JP, Stienen PJ, Doornenbal A, Hellebrekers LJ. Department of Equine Sciences, Faculty of Veterinary Medicine, Utrecht University, 3508 TD Utrecht, The Netherlands. OBJECTIVE: To determine whether epidurally derived evoked potentials (EPs) can be used to reliably assess nociception and antinociception in ponies. ANIMALS: 7 ponies. PROCEDURES: EPs and electromyograms (EMGs) from the quadriceps femoris muscles were recorded simultaneously, following electrical stimulation applied to the distal portion of the hind limb. The effect of increasing stimulus intensity, conduction velocities of the stimulated nerves, effect of epidurally applied methadone, and effect of systemically administered propofol were evaluated. RESULTS: In the EP and EMG waveforms, 2 distinct complexes, the EP N25 and P50 and the EMG P27 and N62, respectively, were identified. On the basis of their latency and calculated conduction velocities, the EP P50 and EMG N62 were considered to be related to nociception (AD-mediated). All complexes increased significantly in amplitude with increasing stimulus intensity and decreased significantly following epidural administration of methadone or systemic administration of propofol. CONCLUSIONS AND CLINICAL RELEVANCE: Although the experimental setup allowed successful discrimination between tactile- and nociceptive-associated responses, the identified EPs, considered to reflect activity in the spinal cord, could not be definitively differentiated from activity in the lumbosacral epaxial musculature. Further research is required to refine measurement techniques to allow for discrimination between these 2 signals. Similar to other species, neurophysiologic variables such as EPs could potentially become a useful additional tool in quantifying nociception in equidae. PMID: 19566465 [PubMed - indexed for MEDLINE]

Impulsivity, a core symptomof attention-deficit hyperactivity disorder (ADHD), is tested in animal models by delay-discounting tasks. So far, mainly male subjects have been used in this paradigm at severe levels of food restriction. Here we studied the impulsive behaviour of CD-1 adult male and female mice at mild levels of food restriction. Mice maintained at 90±5% of ad libitum bodyweight, were tested in operant chambers provided with nose-poking holes. Nose poking in one hole resulted in the immediate delivery of one food pellet (small-soon, SS), whereas nose poking in the other hole delivered five food pellets after a delay (large-late, LL), whichwas increased progressively each day (0–150 s). Two subgroups emerged: individuals that shifted at short delays (“steep”) and individuals that did not shift, even at the highest delays (“flat”). Analysis showed that “steep” females shifted at shorter delays than “steep” males, while no difference existed between males and females within the “flat” sub-population. In homecage circadian activity as well as in a novelty-seeking test, females were more active than males. It can be concluded from these results that female mice are more impulsive than male mice under mild food restriction. This is in contrast with findings in earlier studies with more severe food restriction. Therefore, an alternative explanation is that females are more explorative, and that different features might be tested in delay-discounting paradigms, depending on restriction levels

The response of (laboratory) animals to anaesthetics and analgesics is known to show intraspecies variability. Apart from environmental influences, this may also be caused by genetic factors. In this thesis, rabbit and rat inbred strains were used to identify differences in response to anaesthetics and analgesics in order to provide parameters for a genetic analysis to identify candidate genes involved in this variability. The response to single dose iv bolus injections of propofol, ketamine, medetomidine and xylazine was assessed in the AX/JU and IIIVO/JU inbred rabbit strains using the time between injection and loss of righting reflex and the interval between loss and regain of righting reflex (sleep time). IIIVO/JU had a significantly longer sleep time than AX/JU when propofol and ketamine were administered. Xylazine induced severe excitation in AX/JU. Medetomidine did not induce loss of righting in all male and in six out of eight female AX/JU. The biotransformation rate of medetomidine was determined in both strains as well as the activities of the major hepatic cytochrome P450 (CYP) isoenzymes. The formation rate of hydroxymedetomidine and medetomidine carboxylic acid was significantly higher in AX/JU. Significant correlations were found between the formation rates of both metabolites and CYP2D and CYP2E like activity, as well as between these activities and the sleep time. Using amplified fragment length polymorphism markers a linkage map was constructed that was used for testing co-segregation of markers with the medetomidine metabolite formation rates in F2 intercross progeny. Significant quantitative trait loci (QTLs) were thus located on rabbit chromosomes 1 (near the albino and chloride channel locus) and 18 (near the CYP2E1 locus). When MQM (multiple-QTL model or marker-QTL-marker) mapping was used, an additional QTL (sleep time) was found on an unknown linkage group. The response of eight rat inbred strains ACI, BN, COP, F344, LEW, SHR, WAG and WKY to single doses of two analgesics (buprenorphine, nalbuphine) and three anaesthetics (propofol, medetomidine and ketamine) was determined. The analgesic response was measured using a warm water tail withdrawal procedure. The anaesthetic response was assessed in the same way as with the rabbits. ACI was hyperresponsive to buprenorphine whereas no effect was seen in F344 and WKY. None of the strains were responsive to nalbuphine. For all three anaesthetics significant strain differences in sleep time were found. F344 and BN appeared relatively resistant to medetomidine. ACI and BN appeared hypersensitive to ketamine. In all cases the sleep time of albino strains was significantly longer than pigmented strains. The behavioural response to buprenorphine was assessed in ACI and BN by the Laboratory Animal Behaviour Registration and Analysis System (LABORAS). Apart from significant strain differences in unchallenged behaviour, ACI responded to buprenorphine with a decrease in relative duration of locomotion, drinking and eating. In contrast, both strains showed increases in grooming. In conclusion this thesis describes significant rabbit and rat strain differences in response to anaesthetics and analgesics. The differences in response to medetomidine have been genetically analyzed in the rabbit and candidate genes have been identified.

Item does not contain fulltext Various protocols to induce chronic stress in rodents are being used to determine the effects and underlying mechanisms of prolonged stress experience. Recently, a novel chronic social stress (CSS) protocol has been developed for mice where social instability in adolescence and early adulthood is induced. This protocol has been shown to cause an increase in HPA-axis activity and acute avoidance behaviour in the elevated plus maze. The aim of the present study was to investigate the effect of this CSS protocol on habituation to an initially novel environment in CD1 mice, since it has been shown that initially high avoidance behaviour in mice can still be followed by rapid habituation, pointing towards an adaptive response. One group of male mice, the CSS group, was exposed to the CSS protocol for 7 weeks and we compared their behavioural and physiological responses with male mice that were housed in a stable social group, the SH group. The results reveal a decrease in body weight gain and fur condition, changes in adrenal weight and decreased GR mRNA expression in the CA1 and the dentate gyrus of the hippocampus in chronically stressed CD1 animals. Irrespective of such evidence for a significantly stressful effect of the protocol, CD 1 mice, after termination of the stress procedure, revealed habituation profiles that matched those of control animals. We conclude that the physiological and central-nervous effects caused by a CSS procedure as used in this experiment fall within the coping capacities of CD1 mice at the behavioural level.