Search PubMed⌕ Search

Biomedical subjects

S Eskola

Publications and source records attributed to S Eskola.

8 recordsLinked to original sources

Fighting in NIH/S male mice: consequences for behaviour in resident-intruder tests and physiological parameters.

Fighting is known to occur frequently in male mouse groups. In this study with outbred NIH/S mice, the possible impact of individual aggressiveness on fighting in groups and on the social status of animals was studied. Male mice were pre-tested in a resident-intruder (RI) test and rated as initially aggressive or non-aggressive according to their attack behaviour against an intruder. Thereafter they were randomly allocated to new social groups, with four mice per cage. Fighting in groups was increased when several initially aggressive animals were included in the group. Within the groups, animals were rated as dominants and subordinates according to their behaviour toward a strange intruder introduced into their home-cage (Group Intruder, GI) test and the occurrence of wounds. Additionally, subordinates were divided into aggressive and non-aggressive categories according to their behaviour in the second RI test, which was performed 3 weeks after grouping. The behaviour in the RI test prior to group-housing did not predict the individual social status or possibility of being wounded in the new social environment. On the other hand, the social relationships in the new group affected the behaviour in a subsequent RI test. All dominants showed aggressive behaviour during the second RI test. Those subordinates which behaved aggressively during this test received the most numerous and serious wounds, suggesting that in the new groups their interactions with the other group members were mostly aggressive. The reduced weight of epididymal adipose tissue in dominant and aggressive subordinates may indicate that they had fought continuously. Social status or levels of fighting in a group did not affect individual weight gain or the other physiological parameters measured. The wounded animals had enlarged spleens and reduced weights of epididymal adipose tissue, which were probably the results of increased activity of the immune system and reduced welfare, respectively. In conclusion, individual aggressiveness seems to be greatly affected by the demands of the social environment. Fighting in mouse groups leading to wounded animals may have effects on physiological research parameters.

Adipose Tissue↗

Aspen wood-wool is preferred as a resting place, but does not affect intracage fighting of male BALB/c and C57BL/6J mice.

Aspen wood-wool, provided as nesting material, was evaluated as a possible improvement of cage environment for 10-14-week-old inbred male mice maintained in groups of six (BALB/c n = 72 and C57BL/6J n = 36). The daily behaviour of mice was video recorded and their body weight, food consumption, weights of some organs and serum corticosterone concentrations were measured. Aggressive interactions between cage mates and against a strange intruder as well as the number of wounds on the back of the animals was monitored in order to evaluate the effect of nesting material on intermale aggression. Nesting material did not affect the daily active/passive behaviour patterns of mice, although animals clearly preferred it as a resting place. BALB/c mice given nesting material showed less weight gain and smaller brown adipose tissue weights than animals without nesting material. The other characteristics measured were not affected by the presence of nesting material in either strain. The presence of nesting material had no effect on fighting in cages. C57BL/6J mice were more aggressive than BALB/c mice according to the number of wounded animals in a cage. Wounded BALB/c mice had enlarged spleens and decreased epididymal adipose tissue weights. In conclusion, the nesting material used in this study did not adversely affect the animals. On the other hand, the material was clearly preferred to conventional bedding as a resting place. These findings suggest that nesting material may improve the cage environment of laboratory mice. Furthermore, there was an indication of strain differences in aggressive behaviour. It could be suggested that C57BL/6J mice are less tolerant towards intruders and housing six mice per cage is not suitable for this strain.

Adipose Tissue, Brown↗

Nesting material and number of females per cage: effects on mouse productivity in BALB/c, C57BL/6J, DBA/2 and NIH/S mice.

Two different materials-aspen wood-wool and paper towel-were compared as nesting material for three inbred mouse strains (BALB/c, C57BL/6J and DBA/2) housed in barrier conditions. In addition, the effect of varying the number of females per cage (one to three per cage) of these three strains and with NIH/S outbred mouse stock was studied. The number of litters, litter size and neonatal mortality were determined, as well as age, sex and weight of weanlings. The type of nesting material did not affect the characteristics monitored. In all strains, the number of weanlings per female was greatest in singly-housed females. In terms of the number of weanlings per cage, two females per cage gave the best result. In DBA/2 mice, neonatal mortality increased when several females were caged together.

Animals↗

Effect of access to a running wheel on behavior of C57BL/6J mice.

BACKGROUND AND PURPOSE: To evaluate how and when mice run on a running wheel and how ad libitum access to the wheel affect behavior, feed intake, and weight gain. METHODS: Seventeen 2-month-old C57BL/6J mice had access to the wheel, whereas 19 control mice did not. After 3 to 6.5 weeks, behavior was video-recorded over 24 h for each mouse. RESULTS: Experimental mice ran an average 2 km/24 h in 114 min. Highest running activity took place at the onset of darkness. Experimental mice spent 22 min more feeding on the cage floor than did control mice. These times were deducted from those for all other behaviors: 74 min from resting time, 39 min from climbing and feeding on the cage lid, 14 min from locomotion on the cage floor, and 10 min from grooming. In relative figures, deduction from sleeping time was only 9%, whereas climbing time was halved. CONCLUSIONS: Climbing on the cage lid has a similar circadian rhythm as does wheel running and high-energy expenditure. Because experimental mice climbed less, their weight gain and feed intake were similar to those of control mice. Thus, wheel running can substitute for other forms of energy-consuming behaviors and vice versa.

Animals↗

A comparative prospective clinical study of two single-tooth implants: a preliminary report of 102 implants.

STATEMENT OF PROBLEM: Treatment of tooth loss in the anterior maxilla can involve difficult functional, esthetic, and psychologic problems, especially in young patients with otherwise good dentition. PURPOSE: The purpose of this study was to provide a preliminary comparative evaluation of two implants (ITI and Astra) in single-tooth restorations. MATERIAL AND METHODS: This prospective study of 102 single-tooth replacements with 56 ITI and 46 Astra dental implants was performed in 82 patients at the Finnish Student Health Service Foundation. One Astra implant was lost before loading. The overall survival rate of the implants was 97.8% for Astra implants and 100% for the ITI system. After the initial healing period of at least 6 months, the remaining 101 implants (56 ITI, 45 Astra) were free of periimplant infection and revealed no detectable mobility. Radiographs did not reveal signs of periimplant radiolucencies. All 101 implants received single-tooth crowns. RESULTS: Periimplant parameters and acceptable implant function were examined and demonstrated satisfactory results with preestablished clinical parameters and radiographs at 1 year. During the observation time the mean marginal bone loss was 0.13 mm with Astra implants and 0.11 mm with ITI implants. Subjectively all patients were satisfied with their single-tooth restorations supported by either ITI or Astra dental implants. CONCLUSION: The favorable results of this short-term study support the application of the two implant systems for single-tooth restorations, especially in the anterior region of the maxilla.

Adolescent↗

[Not Available].

Explore the source record for details and available documents.

Finland↗