Male Long Evans rats reared with a Fischer-344 peer during the juvenile period show deficits in social competency: a role for play

Several studies on rats and hamsters, across multiple laboratories, have shown that limiting play in the juvenile period leads to adults that have physiological and anatomical changes in the medial prefrontal cortex (mPFC) and reduced socio-cognitive skills. Peers raised with playful peers have better socio-cognitive skills than animals raised with adult partners. Using Long Evans hooded rats - a commonly used domesticated strain - this relationship has been replicated multiple times. However, when the same paradigm was used with laboratory-reared wild rats, no differences were found between rats reared with peers and ones reared with adults. It has been shown that the key play-generated experiences involved are those related to actively wrestling with a partner and turn taking (as measured by role reversals), which give both partners opportunity to gain the advantage during play fighting. In the present study, we tested the hypothesis that wild rat adults provide juveniles more such experiences than do adult Long Evans rats. The asymmetry in the play interactions in adult-juveniles pairs was compared between the two strains. As predicted, wild rat adults initiated more play with the juveniles, wrestled more and provided more opportunities for role reversals. The findings thus support the hypotheses for the observed strain differences in the effects of rearing condition on the mPFC.

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Effects of Dmo1 on obesity, dyslipidaemia and hyperglycaemia in the Otsuka Long Evans Tokushima Fatty strain

Genetics Research ◽

10.1017/s0016672301004918 ◽

2001 ◽

Vol 77 (2) ◽

pp. 183-190 ◽

Cited By ~ 8

Author(s):

SHIRO OKUNO ◽

TAKESHI K. WATANABE ◽

TOSHIHIDE ONO ◽

KEIKO OGA ◽

AYAKO MIZOGUCHI-MIYAKITA ◽

...

Keyword(s):

Therapeutic Effect ◽

Major Quantitative Trait Locus ◽

Genome Scans ◽

Fischer 344 ◽

Obesity Control ◽

Single Allele ◽

Long Evans ◽

Trait Locus ◽

F344 Rats ◽

Oletf Rat

Whole-genome scans have identified Dmo1 as a major quantitative trait locus (QTL) for obesity and dyslipidaemia in the Otsuka Long Evans Tokushima Fatty (OLETF) rat. We have produced congenic rats for the Dmo1 locus, using marker-assisted speed congenic protocols, enforced by selective removal of other QTL regions (QTL-marker-assisted counterselection), to efficiently transfer chromosomal segments from non-diabetic Fischer 344 (F344) rats into the OLETF background. In the third generation of congenic animals, we observed a substantial therapeutic effect of the Dmo1 locus on lipid metabolism, obesity control and plasma glucose homeostasis. We conclude that single-allele correction of an impaired genetic pathway can generate a substantial therapeutic effect, despite the complex polygenic nature of type II diabetic syndromes.

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Effects of lactation on sodium intake in Fischer-344 and Long-Evans rats

Developmental Psychobiology ◽

10.1002/(sici)1098-2302(199801)32:1<51::aid-dev6>3.0.co;2-s ◽

1998 ◽

Vol 32 (1) ◽

pp. 51-56 ◽

Cited By ~ 9

Author(s):

Celia L. Moore ◽

Beth A. Lux

Keyword(s):

Sodium Intake ◽

Fischer 344 ◽

Long Evans

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Rats show a preference for certain unfamiliar strains of rats

10.1101/2021.02.18.431764 ◽

2021 ◽

Author(s):

Hiroki Kogo ◽

Yasushi Kiyokawa ◽

Yukari Takeuchi

Keyword(s):

Stress Responses ◽

Wistar Rat ◽

Sprague Dawley ◽

Fischer 344 ◽

The Subject ◽

Long Evans ◽

F344 Rats ◽

Anaesthetised Rats ◽

Social Behaviours

AbstractHumans show distinct social behaviours when we recognise social similarity in opponents that are members of the same social group. However, little attention has been paid to the role of social similarity in non-human animals. In Wistar subject rats, the presence of an unfamiliar Wistar rat mitigated stress responses, suggesting the importance of social similarity in this phenomenon. We found that the presence of unfamiliar Sprague-Dawley (SD) or Long-Evans (LE) rats, but not an unfamiliar Fischer 344 (F344) rat, similarly mitigated stress in subject rats. It is therefore possible that the subject rats recognised social similarity to unfamiliar SD and LE rats. In this study, we demonstrated that Wistar subject rats were capable of categorizing unfamiliar rats based on their strain, and that Wistar subjects showed a preference for unfamiliar Wistar, SD, and LE rats over F344 rats. However, the subject rats did not show a preference among Wistar, SD, and LE rats. In addition, the results were not due to an aversion to F344 rats, and preference was not affected when anaesthetised rats were presented to subject rats. The findings suggested that rats recognise social similarity to certain unfamiliar strains of rats.

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