Klas Abelson - Academia.edu (original) (raw)

Papers by Klas Abelson

The present study aimed to develop a method for testing pain-related behaviour induced by formali... more The present study aimed to develop a method for testing pain-related behaviour induced by formalin in the Speke’s hingeback tortoise (Kinixys spekii). These animals retract their head and limbs into their shell when approached, making behavioural testing almost impossible. It was found that suspending the animals in the air, facing away from the observer, made the animals keep their limbs out of the shell. Subcutaneous injection of formalin induced easily identifiable and quantifiable behaviours that lasted for 20 minutes. Contrary to the biphasic effect of formalin observed in rats and mice, the response in tortoises was monophasic. The suspended formalin test may be useful for studying nociceptive mechanisms in tortoises, which in turn will be important for a further understanding of the nociceptive system in reptiles as well as in mammals.

General and comparative endocrinology, Jan 15, 2015

The physiological stress response is frequently gauged in animals, non-invasively, through measur... more The physiological stress response is frequently gauged in animals, non-invasively, through measuring glucocorticoids in excreta. A concern with this method is, however, the unknown effect of variations in diets on the measurements. With an energy dense diet, leading to reduced defecation, will low concentrations of glucocorticoids be artificially inflated? Can this effect be overcome by measuring the total output of glucocorticoids in excreta? In a controlled laboratory setting we explored the effect in mice. When standard mouse chow - high in dietary fiber - was replaced with a 17% more energy-dense diet, fecal mass was significantly reduced. As circulating levels of corticosterone and the total output of corticosterone metabolites over time remained unaffected, the result was an overestimation - more than a doubling - of the corticosterone metabolite excretion if expressed as concentrations. Similar results were obtained for testosterone metabolites. Although measuring the total o...

Laboratory animals, 2014

Facial vein (cheek blood) and caudal vein (tail blood) phlebotomy are two commonly used technique... more Facial vein (cheek blood) and caudal vein (tail blood) phlebotomy are two commonly used techniques for obtaining blood samples from laboratory mice, while automated blood sampling through a permanent catheter is a relatively new technique in mice. The present study compared physiological parameters, glucocorticoid dynamics as well as the behavior of mice sampled repeatedly for 24 h by cheek blood, tail blood or automated blood sampling from the carotid artery. Mice subjected to cheek blood sampling lost significantly more body weight, had elevated levels of plasma corticosterone, excreted more fecal corticosterone metabolites, and expressed more anxious behavior than did the mice of the other groups. Plasma corticosterone levels of mice subjected to tail blood sampling were also elevated, although less significantly. Mice subjected to automated blood sampling were less affected with regard to the parameters measured, and expressed less anxious behavior. We conclude that repeated blo...

PloS one, 2014

Male BALB/c mice single-housed for a period of three weeks were found to respond with a more mark... more Male BALB/c mice single-housed for a period of three weeks were found to respond with a more marked hypothermia to a challenge with a selective serotonergic agonist (8-OH-DPAT) than their group-housed counterparts. This effect of single housing was verified by screening a genetically heterogeneous population of male mice on a C57BL/6 background from a breeding colony. Enhanced activity of the implicated receptor (5-HT1A) leading to an amplified hypothermic effect is strongly associated with depressive states. We therefore suggest that the 8-OH-DPAT challenge can be used to demonstrate a negative emotional state brought on by e.g. long-term single housing in male laboratory mice. The study emphasizes the importance of social housing, and demonstrates that male mice deprived of social contact respond with altered serotonergic signaling activity. Male mice not only choose social contact when given the option, as has previously been shown, but will also, when it is deprived, be negative...

In vivo (Athens, Greece)

The aim of the present study was to evaluate the utility of various non-invasive parameters for t... more The aim of the present study was to evaluate the utility of various non-invasive parameters for the prediction of tumor development and animal welfare in a murine xenograft model in male C.B-17 SCID (C.B-Igh-1(b)/IcrTac-Prkdc(scid)) mice. The study showed that body weight, food and water consumption, and an animal welfare assessment (AWA) protocol revealed marked differences between control and cancer lines as the size of the tumor increased. However, only the AWA protocol was effective in predicting the tumor size and the level of fecal corticosterone metabolites (FCM). FCM levels were, however, negatively-correlated to the AWA score, and the tumor size, both when evaluated on a given day and when accumulated over the entire period. In conclusion, the present study demonstrated that body weight and food and water consumption were negatively-affected as tumor developed but only the animal welfare protocol could be used to predict tumor size.