Fighting Behavior Research Articles

Brain sites responsible for taste-associated odor learning in the rat

Normal and lesioned rats exposed to 3 mg/kg i.p. endosulfan for 10 subsequent days showed elevated foot-shock fighting behaviour in septal and nigral brain-lesioned animals. Increased ipsilateral circling was noticed in unilateral-nigral lesioned rats. A marked decrease in locomotor activity and no seizure pattern were recorded in rats treated with chlorpromazine (CPz). Electroencephalographic recording on the tenth day of endosulfan exposure showed high-voltage slow activity (HVSA) with occasional spindles and 5–6 Hz amplitude of 200 μV. In the treated rats an increase in the concentration of dopamine (DA) and a decrease in serotonin (5-HT) were recorded in amygdaloid, septal and nigral brain-lesioned rats.

Social organization and aggression in a group of olfactory bulbectomized male mice

Olfactory bulbectomized and control male CF-1 strain mice were housed in separate, large, seminatural environments over a 30-day observation period. Control mice engaged in vigorous fighting behavior before a dominant animal emerged. The alpha mouse established the floor area as its territory and vigorously attacked all other mice that ventured from the second tier of the enclosure to the floor. Lower ranking mice had numerous body scars, were much less aggressive, and engaged in a variety of nonaggressive social interactions. In contrast, bulbectomized mice did not fight and roamed freely through all areas of the environment. These mice largely ignored one another, engaged in little or no social behavior, and had no body scars. When two anosmic mice came into physical contact, they appeared startled and moved away from one another. These results, together with those of prior studies, indicate that olfaction plays a critical role in virtually all aspects of social behavior in male mice.

Dominance in Crayfish

I am an 8th-grade student at Westland Middle School in Bethesda, Maryland. I read with interest the article “Neurobiology: Social status sculpts activity of crayfish neurons” by Marcia Barinaga (Research News, [19 Jan., p. 290][1]), which discussed the report “The effect of social experience on serotonergic modulation of the escape circuit of crayfish” by Shih-Rung Yeh et al . in the same issue ([p. 366][2]). A statement in Barinaga's article says that male crayfish display dominance behavior toward other males. My 1995 school science fair project was on the subject of fighting and dominance behavior in crayfish. I paired crayfish, videotaped their encounters, and noted the resulting dominance behavior. I carefully noted the sex of the crayfish. I discovered that not only males fight males, but females fight males and females fight other females. In general, one cannot predict which animal will finally be dominant. That is, females or males can show dominance in a mixed fight. I also observed that relative size or the absence of a claw were not predictors of dominance. [1]: /lookup/doi/10.1126/science.271.5247.290 [2]: /lookup/doi/10.1126/science.271.5247.366

Exposure to violence and victimization and fighting behavior by urban black adolescents

Purpose: We hypothesize that adolescents' exposure to violence and personal victimization will be associated with the frequency with which they engage in fighting behaviors. However, adolescents who are future-oriented and goal-directed and from more secure families are hypothesized to report less fighting behavior. Methods: A cross-sectional, anonymous survey was administered to 225 youths (males = 44%) aged 11–19 years, living in or around nine Housing and Urban Development housing projects in an urban area. The questionnaire contained multiple standardized scales. The dependent variables were the frequency of physical fights, hitting someone with whom the subject lived, and gang fighting during the last year. Results: Previous exposure to violence and victimization, school grade, and number of sexual partners accounted for 16.2% of the variation in frequency of fighting during the last year (based on multiple regression analysis). Exposure to violence and victimization and a family with an unemployed head of household accounted for 11% of the variation in domestic fighting. Exposure to violence and victimization, hopelessness, and anticipated socioeconomic status accounted for 15% of the variation in the frequency of gang fighting. Conclusions: These data support the hypothesis that exposure to, and being a victim of, violence is associated with the frequency of fighting by adolescents.

Cold water swimming stress alters NGF and low-affinity NGF receptor distribution in developing rat brain

We have previously shown that the nerve growth factor (NGF) is released into the bloodstream following intraspecific fighting behaviour and that the level released correlates with the number of fighting episodes. We subsequently reported that NGF and its messenger RNA are present in identified hypothalamic nuclei and increase following intermale fighting behaviour. This report provides data showing that in 16-day-old rats cold water swimming stress (CWSS) alters the distribution of low-affinity NGF-Receptors (p75NGFR) and NGF levels in the central nervous system. A significant increase of NGF level was observed in the cortex, while the p75NGFR immunoreactivity decreased in neurons of the septum, nucleus basalts and striatum. Choline acetyltransferase activity in forebrain tissues remained at baseline levels. Our result suggests that NGF and p75NGFR, involved in the development and differentation of the nervous system, are affected by stress.

Sex Differences and the Role of Aromatization in the Control of Sexually Dimorphic Behavior and Morphology in Gray Short-Tailed Opossums ( Monodelphis domestica)

Sex differences in the activating effects of an aromatizable (testosterone, T) and a nonaromatizable (dihydrotesterone, DHT) androgen on sexually dimorphic scent marking and aggressive behavior were examined in gonadectomized gray short-tailed opossums. When compared with males, females showed less chest, head, flank, and hip marking and more fighting behavior in tests with stimulus females and threat behavior in tests with stimulus males following receipt of subcutaneous T, DHT, or blank (B) implants. Testosterone but not DHT activated hip and head marking while both T and DHT activated flank marking. In tests with stimulus females, only males showed clicking vocalizations and T but not DHT or B stimulated clicking. Animals that received T had significantly larger suprasternal scent glands than those that received DHT or B. The significance of these findings is discussed with respect to the development of sex differences in behavior in eutherian mammals.

Behavior of ergatoid males in the ant,Cardiocondyla nuda

Ergatoid males of the ant,Cardiocondyla nuda, attack and frequently kill young males during or shortly after eclosion. Smaller colonies therefore contain typically only one adult male, which may inseminate all alate queens which are reared in the colony over a few weeks. In larger colonies, several males may be present, however, fighting among adult males was not observed. We discuss the significance of male fighting behavior in ants.

Evaluation of xanthotoxol for central nervous system activity

Xanthotoxol (XT), 8-hydroxypsoralen, exhibited dose-graded sedative activity in dogs, cats, rats, mice and hamsters. At doses of 5–20 mg/kg intraperitoneally (i.p.) in cats and 3–100 mg/kg orally (p.o.) in dogs, XT blocked predatory mouse/rat killing behavior. In mice, XT (10–300 mg/kg i.p.) exhibited a dose-dependent reduction in locomotor activity but was less potent in this regard than reference diazepam (10–100 mg/kg i.p.). XT in mice (0.1–10.0 mg/kg i.p.) and in hamsters (0.1–10.0 mg/kg p.o.) antagonized amphetamine-induced hypermobility but was less potent than diazepam. XT elevated the electrical threshold in foot-shock-induced fighting behavior in rats. XT (0.1–30.0 mg/kg p.o.) potentiated pentobarbital-induced narcosis in hamsters at otherwise subeffective doses of pentobarbital. Conditioned avoidance responses in rats were not significantly altered with 1–3 mg/kg i.p. and 30–100 mg/kg p.o. doses of XT but 300 mg/kg p.o. blocked both conditioned and unconditioned response. Doses of 100–1000 mg/kg i.p. of XT in mice were used to study 48-h acute toxicity of XT and its LD 50 was estimated to be 468 mg/kg. Doses of 10, 40 and 80 mg/kg p.o. were used to study the chronic toxicity of XT in rats for 6 months and no side effects or abnormalities in reproductive activity or endocrine integrity were noted. The F 1 generation of rats from 6-month XT-treated parents were free of teratogenic effects.

Lack of increased intermale fighting behavior in mice after low ethanol doses

The effect of ethanol on intermale fighting behavior, measured mainly as the total fighting time, was studied using Swiss-Webster mice in 5-min encounters in a neutral arena (i.e., not the home cage). Ethanol treatment compared to control treatment had no statistically significant effect on fighting behavior when given to both equal-sized members of a pair of males socially isolated for a) 5 or 10 days at a dose of 0.4 g/kg IP; b) 4 weeks at 0.8 g/kg IP; and c) 38 weeks at 0.4 g/kg IP. Moreover, no significant effect was found when ethanol was given only to the expected dominant member of a pair, that is, to: a) a male isolated for 48 weeks confronting a younger and smaller group-housed male at 0.4 g/kg PO; and b) a male that had been pair housed with a female conspecific for 5 weeks confronting a group-housed male of equal age and weight at 0.4 g/kg IP. The results suggest that under these conditions ethanol does not lead to increased fighting behavior in Swiss-Webster male mice.

Effects of alcohol dependence on shock-induced fighting: Action of muscimol and homotaurine

We have applied the electroshock-induced fighting behavior to the study of experimental alcohol dependence. Adult Wistar rats were intoxicated chronically with ethanol (10 g/kg/24 h) for 13 days. Electroshock-induced fighting behavior was studied during chronic intoxication and withdrawal in comparison with normal rats receiving a water-carbohydrate solution isocaloric to ethanol. Rats were divided into groups receiving respectively muscimol (0.25 mg/kg), a GABAA agonist; homotaurine (140 mg/kg) a GABA mimetic; and physiological saline (10 ml/kg), intraperitoneally. During chronic intoxication, rats showed an increase in defensive-fighting behavior. Withdrawal accentuated the aggressive behavior and muscimol and homotaurine inhibited it. These results confirm the relevance of the electroshock-induced defensive fighting behavior test in chronic intoxication with alcohol, but to show the involvement of GABAergic transmission in the behavioral effects of alcohol withdrawal, additional experiments with other GABA mimetics and with GABA antagonists should be considered.

Chronic stress reduces fighting behavior of rats: The effect of antidepressants

The effect of chronic stress (14 various unpredictable stressors over 16 days) on electric footshock-induced fighting behavior of pairs of male Wistar rats was studied. The influence of antidepressant drugs (imipramine, desmethylimipramine, nomifensine, clomipramine, mianserine and doxepine) administered chronically (1 h before the stressor) on the aggressive behavior was also investigated in control and in stressed rats. Moreover, the effect of chronic stress on noradrenaline (NA) utilization in the brain was estimated in control and in antidepressant-treated rats. It was demonstrated that, in rats submitted to repeated unpredictable stress, the fighting behavior was significantly reduced 48 and 72 h after the last stressor. NA utilization in the brain was decreased 72 h after the stress termination. Prolonged treatment with antidepressant drugs restored the intensity behavior in stressed rats to control value as well as normalized NA utilization in the brain. It is suggested that antidepressant drugs may counteract the affective aggression deficit induced by chronic stress.

Disruptive boys with stable and unstable high fighting behavior patterns during junior elementary school

Boys' fighting was assessed at ages six, eight, and nine. The boys (N = 69) had been selected from the 30% most disruptive children in kindergartens from low socioeconomic neighborhoods. Twenty-three percent of these disruptive boys were rated as high fighters on three assessments ("stable high fighters"), and 28% were rated as high fighters on two of the three assessments ("variable high fighters"). Forty-two percent were rated as high fighters only one out of three assessments ("occasional high fighters") and 7% were never rated as high fighters. Only high fighting in two successive years significantly increased the risk of being rated a high fighter in a following year. At age 10, stable high fighters (high fighters at ages 6, 8, 9) were perceived by teachers, peers, mothers, and the boys themselves as more disruptive and more antisocial than occasional high fighters. These results show an impressive self-other agreement in boys who have adopted a physically aggressive life style from an early age. The three groups did not differ on individual family demographic characteristics, but stable high fighters had a higher mean on an index of family socioeconomic disadvantage. Results indicate that the aggression scales which include only a few physical aggression items and many disruptive items (oppositional behavior, rejection, hyperactivity, inattention, etc.) probably aggregate two kinds of disruptive boys, the high-frequency fighters at high risk for stable disruptive, physically aggressive, and antisocial behaviors, and the disruptive low-frequency fighters who are at a lower risk of stable disruptive behavior and at a lower risk of early antisocial behavior.

大型と小型のスンクス (<I>Suncus murinus</I>) 2系統間での正逆交配の試み

We conducted mating experiments between two laboratory strains of musk shrews (Suncus murinus), the large-sized shrews (BAN strain) originating from Bangladesh and the small-sized animals (NAG strain) from Nagasaki, Japan. In the 16 mating trials between 12 BAN females (mean body weight of 87.9 g) and 11 NAG males (52.3 g), highly aggressive fighting behaviors of the BAN females toward the NAG males were observed. The BAN females stayed in nest boxes in cages, whereas the NAG males kept out during the mating trials. No pregnant females were found in the trials. Their pregnancies were diagnosed by palpation on the day about 16 days after the separation of the pairs. Contrastively, in 6 of the 11 trials between 8 NAG females (34.2 g) and 6 BAN males (145.9 g), the viable and fertile F1 hybrids of 8 females and 8 males were produced. The F1, subsequent F2 and backcross progenies appeared neither external nor behavioral abnormalities. Various types of crosses using the F1, F2, and the two parental shrews showed that mating success was in a condition that females were nearly as heavy as males, or lighter. Although body weights of musk shrews from different geographical areas were reported to vary from 43.5 to 147.3 g in males and from 26.0 to 82.0 g in females, males in respective localities were constantly about 1.7 times heavier than the corresponding females. These results therefore suggest that body-weight differences between sexes paired greatly affect mating success in the cross between the strains of induced ovulatory shrews.

Parental Care, Sibling Relationships and the Development of Aggressive Behaviour in Two Lines of Wild House Mice

Distinct behavioural strategies for dealing with environmental and social challenge are known to exist in the adults of a variety of mammalian species, but little is known about the developmental bases of these strategies. In an attempt to start to fill this gap in knowledge, the present study set out to describe and compare the development of males from two lines of wild house mice which are known to differ in their aggressive behaviour and response to challenging situations. Adult males from one line (Short Attack Latency = SAL line) are more aggressive, show less sensitivity to changes in their environment and behave in a more internally controlled, routine-like way, than do males from the other line (outbred = Control line). The parental care and development of eight litters of four male pups from each line was observed. Paternal care did not differ between the two lines, but SAL pups received higher levels of nursing and general maternal care than did Control pups, and they appeared to be weaned later. Despite these differences, SAL pups grew more slowly than Control pups, suggesting that their high levels of sucking behaviour were a reflection of high milk demand, perhaps due to a low milk supply, rather than high milk intake. SAL pups were also delayed in a number of measures of early behavioural development relative to Control pups. The apparent early retardation in certain measures of SAL pup behavioural development disappeared at the end of the parental care period. From day 32 onwards, SAL pups began to show higher levels of aggression towards each other than did Control pups, and also showed a reduced reactivity to tests involving changes to the home cage environment ; a characteristic of adult SAL males. As expected, SAL males developed into faster attackers than Control males and, in SAL litters, intra-litter variation in attack speed was strongly influenced by preceding experience of sibling aggression. The fastest attackers in each litter were more successful in fights occurring in their litter than their slowest attacking siblings. No such relationship was observed in the Control litters where levels of inter-sibling aggression were low. The results point to the potential significance of maternal care behaviour and pup fighting behaviour in the development of the fast-attacking phenotype. One hypothesis is that inadequate nutrition of young SAL pups, mediated through the mother, promotes increased competition for access to the mother's nipples and predisposes the pups to develop into more active/competitive individuals. Subsequent sibling-sibling aggression appears to influence intra-litter variation in adult attack latency.

Influence of Two Mass-Marking Techniques on Survival and Flight Behavior of Diabrotica virgifera virgifera (Coleoptera: Chrysomelidae)

Two mass-marking techniques were evaluated in the laboratory to determine effects on survival and flight behavior of Diabrotica virgifera virgifera LeConte. The marking agents were an externally applied fluorescent powder (Day-Clo) and an internal oil soluble dye (Calico oil red) incorporated into an artificial adult diet. Neither technique had a significant influence on survival of 5-10-d-old or 20-25-d-old female or male beetles up to 10 d after marking. Based on tethered-flight assays, marking with fluorescent dust generally had no effect on trivial or sustained flight performance of 5-10-d-old and 20-2S-d-old females or 15-d-old males. Beetles marked with the oil-soluble dye experienced reductions in trivial flight performance, including reductions in individual flight duration, frequency of flight, and total flight time in a 23-h period, for up to 2 d after marking. Both techniques are efficient, but in comparison with Day-Glo fluorescent powder, beetles marked with Calico oil red retain the mark for a shorter time period. Also, beetles marked with Calico oil red should be provided suitable food for at least 2 d after marking to allow recovery of normal fight behavior before they are used in studies involving flight activity.

Perceived Consequences Associated With the Use of Beer, Wine, Distilled Spirits, and Wine Coolers

Based on a national probability sample of 2,401 Americans aged 21 and over (1,069 of whom were deemed "drinkers" on the basis of having drunk at least one alcoholic beverage in the past 7 days), this study examines which of six specific problems people associate with the use of beer, distilled spirits, wine, and wine coolers. It was found that people are most likely to associate alcoholism, birth defects, drunk driving, and fighting and rowdy behavior equally with these four types of alcohol. But when beverage associations are made, distilled spirits and beer are blamed most frequently for these problems, whereas wine and wine coolers are virtually never thought of as being closely related to any of the problems under study. It was also determined that nearly 1 out of every 7 drinkers surveyed stated that birth defects are unrelated to alcohol use of any kind.

Dopamine autoreceptor agonists attenuate spontaneous motor activity but not spontaneous fighting in individually-housed mice

The present study was conducted to determine whether or not two behavioral characteristics of individually-housed mice, hyperactivity in a novel environment and intermale fighting, are attenuated by the dopamine (DA) agonists, apomorphine, (+)- and (-)-3-(3-hydroxyphenyl)-N-n-propylpiperidine (3-PPP). Autoreceptor-activating doses of these drugs which reduced spontaneous activity in a novel environment did not inhibit spontaneous fighting with conspecific olfactory bulbectomized males. Individually-housed mice were more active in a novel environment and showed a significant reduction of activity at lower doses of apomorphine, (+)- and (-)-3-PPP than group-housed mice. However, the ED50's for the inhibition of spontaneous activity in a novel environment in group- and individually-housed mice were similar: apomorphine, 0.02 vs. 0.012 mg/kg, SC; (+)-3-PPP, 0.50 vs. 0.51 mg/kg, SC; and (-)-3-PPP, 1.0 vs. 0.56 mg/kg, SC, for group- and individually-housed mice respectively. A significant proportion of individually-housed mice, but not group-housed mice, displayed catalepsy in response to high doses of (-)-3-PPP. These data suggest that DA autoreceptor agonists can modulate the hyperactivity syndrome but not spontaneous fighting behavior in individually-housed mice.

Automated method for measuring fighting behavior and locomotor activity of mice

A multiunit apparatus for automatic quantification of intermale fighting behavior and locomotor activity of mice is described. The method uses static charge sensitive beds (SCSB) to detect movement, and appropriate hard- and software for data acquisition and analysis. The data obtained with the SCSB-method correlated well with those observed from video-recordings of the same 60 aggression trials for determining both the total fighting times (r=.967) and the latencies to first fighting (r=.982). d-Amphetamine significantly increased locomotor activity counts on the SCSBs, and this increase was blocked by haloperidol. It is concluded, that the SCSB-method is an accurate and flexible technique for quantifying intermale fighting behavior and locomotor activity of mice.

Reproductive and kid performance of a newly established feral goat herd being graded up for cashmere production

Interest in farming goats for cashmere production has recently arisen, both as a means of farm diversification and, through goats grazing preferences, to utilise previously under exploited resources on hill farms.A herd of 160 feral does of Irish and Scottish origin was established at the West of Scotland College's Kirkton Unit in June 1987 to investigate the potential for cashmere production from goats on a hill sheep farm. The Irish goats are of mixed ancestry with obvious dairy crossbreds in addition to many of more feral phenotype. The Scottish feral does came as an established group but proved excitable and difficult to handle. Whenever goats were grouped together for handling or at feeding points there was considerable fighting and other agonistic behaviour. A year later the level of this has reduced.One hundred and fifty eight does were divided into four groups and oestrus synchronised (goats sponges 45 mg progesterone supplied by Intervet). These were then artificially inseminated by laparoscope in two, two day sessions a week apart (21/10, 22/10, 29/10 and 30/10).

Role of neurotransmitters in fenitrothion-induced aggressive behaviour in normal and lesioned rats

Normal and brain-lesioned (amygdala, septal and nigral regions) rats exposed to fenitrothion (10 mg/kg) for 15 subsequent days showed elevated foot-shock fighting behaviour (septal and nigral lesioned rats). Treated animals failed to perform the rotorod test and showed decreased locomotor activity followed by convulsions. The brain-lesioned rats treated with 10 mg/kg fenitrothion showed a marked decrease in the level of norepinephrine (NE) and serotonin (5-HT).