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Quantitative scores for 4 behavioural patterns, especially those of an antagonistic nature, were recorded from wild individual of Mus musculus mutsculus Linnaeus, 1758 living in semi-confinement in an outdoor enclosure divided into four pens. The enclosure was "permeable", in that mice were able to move between pens and between the enclosure and the outside. The population was monitored by the capture-mark­-recapture method. In the spring of 1988 and 1989 the behaviour of mice trapped in the enclosure was studied in unisexual encounters in a neutral arena. There were no significant differences in scores for behaviour in relation to the degree of spatial separation of the places of capture of individuals paired together (except in the number of attempts to escape noted for females in 1989 and the total activity noted for males in 1988). Males and females did not differ significantly in scores for aggressive behaviour, but mice were more aggressive and more active in 1989 when the popu­lation in the enclosure was smaller, than in 1988, when it was larger.
An unique observation was made when an adult yellow-necked mouse Apodemus flavicollis (Melchior, 1834) attacked a dead bank vole Clethrionomys glareolus (Schreber, 1780).
We investigated the effect of injections of four biogenic amines (serotonin, dopamine, octopamine and tyramine) on behavior patterns displayed by workers of the red wood ant Formica polyctena during dyadic confrontations with four types of opponents: a nestmate, an alien conspecific, an allospecific ant (Formica fusca), and a potential prey, a nymph of the house cricket (Acheta domesticus). Significant effects of biogenic amine administration were observed almost exclusively in the case of confrontations with allospecific opponents. Serotonin treatment exerted stimulatory effects on behavior patterns involving physical aggression (biting accompanied by gaster flexing, dragging and formic acid spraying), but these effects were relatively weak and/or documented by indirect evidence. Dopamine administration exerted a stimulatory effect on open-mandible threats directed by F. polyctena to F. fusca and to cricket nymphs, and on biting behavior directed to cricket nymphs. Surprisingly, octopamine treatment did not exert significant effects on aggressive behavior of the tested ants. Tyramine administration exerted a suppressing effect on threatening behavior directed to F. fusca, but led to shortening of the latencies to the first open-mandible threat during the tests with cricket nymphs. Biogenic amine administration also influenced non-aggressive behavior of the tested ants. Our findings confirmed the role of serotonin and dopamine in the mediation of ant aggressive behavior and documented for the first time significant effects of tyramine treatment on ant aggressive behavior. We also demonstrated that not only specific patterns of ant aggressive behavior, but also behavioral effects of biogenic amine treatments are as a rule strongly context-dependent.
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Aggressive behaviors in domestic cats (Felis catus)

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Aggressive behaviors in domestic cats (Felis catus) Behavioral issues of cats include: furniture scratching, aggression, anxiety, over-stimulation, exaggerated vocalizations and excreting outside the litter box. Among these, aggression - both passive and active – is the most commonly encountered problem. Aggressive behavior is a complex phenomenon, dependent on both genetic and environmental factors. Among the factors leading to agonistic behavior two categories are distinguished: psychobiological factors (which include biochemical and physiological processes, disposition and mood, emotional reactions, motor actions and vegetative reactions) and environmental factors (such as incorrect socialization, unfriendly surroundings or irresponsible animal owners) . The most widespread type of aggression in cats reared in groups is linked to the desire to gain and maintain their territory. Another type of agonistic behavior is one born out of fear, exhibited by cats in a crisis situation once there is no escape route, and the animal is certain it has to fight to survive. This behavior differs from others in that aggression is here the last resort and not the first response to a disturbing situation. Another source of aggression may be anxiety caused by a sudden change in the environment, the presence of people and other animals. An interesting type of aggression linked to the natural hunting sequence of cats is aggression during play, which especially affects cats during adolescence. While working with an aggressive animal, a caregiver has a range of different mitigating and calming measures at hand, but their proper selection requires experience and cooperation with a veterinarian and a behaviorist).
We conducted an experimental study to test the hypothesis that, at low female availability, males show intrasexual aggressive behaviour and home range owners are more aggressive than home range intruders. Using field dyadic arena test, we carried out 35 male–male trials in four 0.25 ha enclosures, two male-biased (experimental enclosures) and two unbiased (control enclosures). Dyadic encounters were conducted between unrelated and sexually mature males of similar weight and age which established home ranges in the same enclosure at the same trapping session. Each inter-male encounter was performed in the home range of one of the opponents between the home range owner and a home range intruder. When sex ratios were male-biased, inter-male amicable behaviour was absent and we found significant rates of inter-male aggressiveness, being home range owners much more aggressive than intruders. In the unbiased enclosures, inter-male encounters resulted mainly in noninteractive or amicable interactions. We found that inter-male aggression varied in relation to female availability being more evident in home range owners.
In this mini-review we were interested in describing the main genetic, biological and mechanistic aspects of the aggressive behaviour in human patients and animal models. It seems that violent behaviour and impulsive traits present a multifactorial substrate, which is determined by genetic and non-genetic factors. Thus, aggressivity is regulated by brain regions such as the amygdala, which controls neural circuits for triggering defensive, aggressive or avoidant behaviour. Moreover, other brain structures such as the anterior cingulate cortex and prefrontal cortex regionscould modulate circuits involved in aggression. Regarding the genetic aspects, we could mention the mutations in the monoamine oxidase or the polymorphisms of the genes involved in the metabolism of serotonin, such as tryptophan hydroxylase. Also, besides the low levels of serotonin metabolites, which seem to be associated with impulsive and aggressive traits, there are good evidences that deficiencies in glutamate transmission, as well as testosterone, vasopressin, hypochloesterolemia or oxytocin modifications could be related to the aggressive behaviour. Regarding oxytocin we present here in the last chapter the controversial results from the current literature regarding the various effects exhibited by oxytocin administration on the aggressive behavior, considering the increased interest in understanding the role of oxytocin on the main neuropsychiatric disorders.
Studies were carried out on one of the largest European red foxVulpes vulpes (Linnaeus, 1758) farms in Śniaty and Batorówka (Poland). A test created by Nowicki and Przysiecki (NP) was used to describe behaviour of the animals. The results of the NP behaviour test showed 4 types of behaviour in foxes: aggressive, curious, indifferent and apprehensive. While analyzing a fragment of exon 1 in the androgen receptor gene in 184 individuals, four alleles were found, ie 10, 10T, 12 and 13. The most frequent allele was allele 10, both in males and females (65.85 and 57.39%, respectively). The next in order of frequency were allele 10T (24.39 and 31.25%), 13 (7.32 and 9.09%) and 12 (2.44 and 2.27%, respectively). On the basis of further analysis an association was shown between behaviour of the red fox and its genotype. In aggressive females allele 10 was found significantly more frequently (76%) than in curious females (57%). While analyzing the genotypes of aggressive females it was shown that there were 15 individuals with genotype 10/10 (15.56%), 11 heterozygotes (9.87%) and only 1 individual with genotype 10T/10T (1.56%). In curious females the distribution of these genotypes was 15 (13.71%), 18 (20.57%) and 9 (7.71%), respectively. Although the result of Pearson Χ2 analysis was not significant (Χ2,p=0.0793), the Armitage’s chi-squared test for trend showed a significant difference Χ2,p=0.0305). This results may suggest that the androgen receptor gene may be suitable in studies on psychological traits.
The paper is devoted to enslavement of adult Formica cinerea cinerea Mayr workers by Formica sanguinea Latr., a phenomenon hitherto unknown under natural conditions. Suc enslavement follows periodic invasions and temporary occupation of nests of slave species by F. sanguinea. During the occupation of their nest, some F. cinerea workers join the occupants colony. The studies were made m Poland and in Finland between 1994 and 1996.
The density and behavior of the Mistle Thrush in Niepołomice Forest (southern Poland) and adjacent open areas were studied during winter (December-February) in 1996/97, 1998/99 and 2000/01. Mistle Thrush densities differed significantly from winter to winter, and the abundance of thrushes decreased as the season progressed. Bird density and mistletoe clump density were correlated positively. Birds held territories or congregated in flocks. The latter were sighted in the forest only during winter 1996/97, when the largest density of birds was noted. Flock size decreased progressively during that winter, but at the same time, the number of territorial birds remained stable. This suggests that by the end of the winter 1996/97 some birds from the flocks had begun to hold territories. Flocks were also seen in open areas, and displayed a preference for foraging on pastureland. Each individual territory in the forest consisted of several clumps of mistletoe on a few adjacent trees, which were defended against both conspecifics and other species such as Pyrrhula pyrrhula, Turdus merula and Dendrocopos major. The aggressive encounter rate was correlated positively with bird density but negatively with the progress of winter (the latter was correlated negatively with the berry supply). Surprisingly, it was not correlated with mistletoe clump density or temperature. During abundant berry years, the density of birds may have been so large that defending the fruit against numerous neighbors would have been energetically less profitable than communal foraging.
Evidence for direct interspecific competition in wildfowl and between hybrids and their parent species is scarce. This study examined threat displays and agonistic encounters (n = 324) in a goose flock of 140 Swan Geese and 13 hybrids with Greylag Goose living in Heidelberg, SW Germany. In general, agonistic behaviour made up less than 1% of the time budget throughout the year as measured by focal animal sampling. Most encounters (84%) were won by the initiator, both in Swan Geese and in hybrids. No difference was found between Swan Geese and hybrids in the outcome of an encounter, suggesting equal competitive quality. There were differences with respect to threat postures with hybrids performing diagonal neck threats more often and intentional movements less often. This seems to be related to their hybrid origin, since Greylag Geese most often show diagonal neck and forward threat displays. There was no direct evidence for hybrid superiority or inferiority.
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