Are staged dyadic encounters useful for studying aggressive behaviour of arvicoline rodents?

1997 ◽  
Vol 75 (7) ◽  
pp. 1051-1058 ◽  
Author(s):  
Steven J. Harper ◽  
George O. Batzli

We investigated the aggressiveness of adult prairie voles (Microtus ochrogaster) in dyadic encounters staged in different types of arena trials to determine if responses differed (i) between neutral arena trials conducted in the laboratory and resident–intruder trials conducted in the field, (ii) between trials staged before and after 3 months of isolation from social contact, (iii) between voles reared in the laboratory and voles reared in the field, and (iv) among trials staged with the same individual over time. Though rodents are usually expected to be more aggressive on their own home range, female prairie voles tended to be more aggressive in neutral arenas. Males showed no difference in aggression between trials held in neutral arenas and trials held in arenas placed in their home ranges. Aggressiveness was not affected by 3 months of isolation for either males or females, suggesting that recent social cues may not strongly influence aggressive behaviour in this species. Voles reared in the laboratory were significantly more aggressive than those reared in enclosed field populations, which suggests that direct comparisons of field and laboratory studies of aggressive behaviour may be suspect. Individuals showed little change in aggressiveness when tested over several weeks in three trials with different opponents. We conclude that encounters staged in arenas provide standardized estimates of aggressiveness that are robust to differences in testing procedures and are repeatable over time. Therefore, their continued use seems warranted for studying aggressive behaviour of voles and lemmings.

2020 ◽  
Vol 79 (4) ◽  
pp. 478-487
Author(s):  
Martin Kellner ◽  
K. Håkan Olsén

AbstractSelective serotonin reuptake inhibitors (SSRIs) are psychotropic pharmaceuticals used as antidepressants. SSRIs are commonly found in surface waters in populated areas across the globe. They exert their effect by blocking the serotonin re-uptake transporter in the presynaptic nerve ending. The present study examined whether behavioural effects to exposure to SSRI citalopram depend on personality and sex in the stickleback (Gasterosteus aculeatus). Three aspects of stickleback behaviour are examined: feeding behaviour, aggression, and boldness. We exposed sticklebacks to 350–380 ng/l citalopram for 3 weeks. Feeding and aggressive behaviour were recorded before and after exposure, whereas scototaxis behaviour was tested after exposure. The results show treatment effects in feeding and aggressive behaviour. Feeding is suppressed only in the male group (χ2 = 20.4, P < 0.001) but not in the females (χ2 = 0.91, P = 0.339). Aggressive behaviour was significantly affected by treatment (χ2 = 161.9, P < 0.001), sex (χ2 = 86.3, P < 0.001), and baseline value (χ2 = 58.8, P < 0.001). Aggressiveness was suppressed by citalopram treatment. In addition, the fish showed no change in aggression and feeding behaviour over time regardless of sex and treatment, which indicate personality traits. Only females are affected by treatment in the scototaxis test. The exposed females spent significantly (χ2 = 5.02, P = 0.050) less time in the white zone than the female controls.


1990 ◽  
Vol 68 (2) ◽  
pp. 391-398 ◽  
Author(s):  
Betty McGuire ◽  
Theresa Pizzuto ◽  
Lowell L. Getz

Many hypotheses on the role of social behavior in population regulation of microtine rodents assume that social interactions are more frequent at high density than at low density. We evaluated this assumption by measuring potential for social contact in a population of prairie voles (Microtus ochrogaster). Our livetrapping regime monitored presence of resident and nonresident animals at the periphery of home ranges of social groups. Resident adults and young of both sexes were captured at home range boundaries. Potential for social interaction with nonresidents was greater at the periphery of home ranges than at nests. Intruders tended to be male adults from neighboring social groups. Presence of adult males in the resident group played an important role in deterring visits by nonresident males. During the spring, summer, and autumn reproductive period, number of captures of nonresident males, but not females, showed a strong positive relationship with population density. Despite relatively high densities during the winter nonreproductive period, there were few captures of residents and nonresidents at the periphery of home ranges. We conclude that the relationship between potential for social interaction and population density varied as a function of sex and season.


Author(s):  
Thomas Persson

This chapter analyzes mechanisms for policy coordination inside and outside Sweden’s Government Offices. It looks at how governments of different types have coordinated their policies, and focuses on the mechanisms used by single-party minority governments and by coalition minority and majority governments. Over time, Swedish political parties have developed methods for achieving stable, long-term cooperation, and these methods have become increasingly formalized and institutionalized. Coordination at the national level takes place both before and after elections, and tends to blur the boundary between majority and minority governments. These new patterns of cooperation pose new challenges to the government’s ability to coordinate policy.


2001 ◽  
Vol 16 (8) ◽  
pp. 459-465 ◽  
Author(s):  
N. Sjöström ◽  
D.N. Eder ◽  
U. Malm ◽  
J. Beskow

SummaryAggressive behaviour in psychiatric inpatients was assessed before and after a training course for staff members. The Social Dysfunction Aggression Scale (SDAS) was used to report and assess aggressive behaviour over time, and the Staff Observation Aggression Scale (SOAS) to report and assess single aggressive incidents. In addition, the numbers of nursing staff members who were on sick leave because of injuries in the periods before and after the course were recorded and compared. No statistically significant reduction was found in the number of aggressive patients or in the number of staff members on sick leave. One interesting finding was a lower reporting on the SOAS of perceived aggressive incidents after the training course in comparison with the SDAS reports. Directed verbal aggressiveness and violence towards things were found to be predictors of violence.


1998 ◽  
Vol 3 (4) ◽  
pp. 271-280 ◽  
Author(s):  
Hannah Steinberg ◽  
Briony R. Nicholls ◽  
Elizabeth A. Sykes ◽  
N. LeBoutillier ◽  
Nerina Ramlakhan ◽  
...  

Mood improvement immediately after a single bout of exercise is well documented, but less is known about successive and longer term effects. In a “real-life” field investigation, four kinds of exercise class (Beginners, Advanced, Body Funk and Callanetics) met once a week for up to 7 weeks. Before and after each class the members assessed how they felt by completing a questionnaire listing equal numbers of “positive” and “negative” mood words. Subjects who had attended at least five times were included in the analysis, which led to groups consisting of 18, 20, 16, and 16 subjects, respectively. All four kinds of exercise significantly increased positive and decreased negative feelings, and this result was surprisingly consistent in successive weeks. However, exercise seemed to have a much greater effect on positive than on negative moods. The favorable moods induced by each class seemed to have worn off by the following week, to be reinstated by the class itself. In the Callanetics class, positive mood also improved significantly over time. The Callanetics class involved “slower,” more demanding exercises, not always done to music. The Callanetics and Advanced classes also showed significantly greater preexercise negative moods in the first three sessions. However, these differences disappeared following exercise. Possibly, these two groups had become more “tolerant” to the mood-enhancing effects of physical exercise; this may be in part have been due to “exercise addiction.”


2013 ◽  
Author(s):  
Sandra J. Winter ◽  
Jylana L. Sheats ◽  
Lauren A. Grieco ◽  
Eric B. Hekler ◽  
Matthew P. Buman ◽  
...  

2019 ◽  
Author(s):  
Vince Polito ◽  
Amanda Barnier ◽  
Erik Woody

Building on Hilgard’s (1965) classic work, the domain of hypnosis has been conceptualised by Barnier, Dienes, and Mitchell (2008) as comprising three levels: (1) classic hypnotic items, (2) responding between and within items, and (3) state and trait. The current experiment investigates sense of agency across each of these three levels. Forty-six high hypnotisable participants completed an ideomotor (arm levitation), a challenge (arm rigidity) and a cognitive (anosmia) item either following a hypnotic induction (hypnosis condition) or without a hypnotic induction (wake condition). In a postexperimental inquiry, participants rated their feelings of control at three time points for each item: during the suggestion, test and cancellation phases. They also completed the Sense of Agency Rating Scale (Polito, Barnier, &amp; Woody, 2013) for each item. Pass rates, control ratings, and agency scores fluctuated across the different types of items and for the three phases of each item; also, control ratings and agency scores often differed across participants who passed versus failed each item. Interestingly, whereas a hypnotic induction influenced the likelihood of passing items, it had no direct effect on agentive experiences. These results suggest that altered sense of agency is not a unidimensional or static quality “switched on” by hypnotic induction, but a dynamic multidimensional construct that varies across items, over time and according to whether individuals pass or fail suggestions.


Author(s):  
P.A. Popov ◽  
◽  
D.V. Gruznov ◽  
S.V. Tokarev ◽  
◽  
...  

The article presents the results of determining the relationship between the total microbial number and microbial ATP on the surface of milking equipment before and after treatment with neutral anolyte ANK-SUPER. The possibility of using the ATP-bioluminescence method to control the quality of sanitation of milking equipment on dairy farms is shown. Laboratory studies revealed a proportional relationship between the level of bacterial ATP and the number of bacteria on the surface of milking equipment before and after sanitation.


Author(s):  
Christopher Hood ◽  
Rozana Himaz

This chapter draws on historical statistics reporting financial outcomes for spending, taxation, debt, and deficit for the UK over a century to (a) identify quantitatively and compare the main fiscal squeeze episodes (i.e. major revenue increases, spending cuts, or both) in terms of type (soft squeezes and hard squeezes, spending squeezes, and revenue squeezes), depth, and length; (b) compare these periods of austerity against measures of fiscal consolidation in terms of deficit reduction; and (c) identify economic and financial conditions before and after the various squeezes. It explores the extent to which the identification of squeeze episodes and their classification is sensitive to which thresholds are set and what data sources are used. The chapter identifies major changes over time that emerge from this analysis over the changing depth and types of squeeze.


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