Aggression In Cats Research Articles

Non-recognition Aggression in Cats

When a cat is taken out of their home and then taken back, for example to the veterinarian, they can experience "non-recognition aggression." Even cats who previously had a strong affiliative relationship can fail to recognize each other under certain circumstances, and show aggressive behaviors as a result. This article summarizes a small citizen science project looking at what cat guardians have tried to prevent and address non-recognition aggression in the cats in their household.

Effect of Exposure to Lead Acetate on Neurobehavior and Learning in the Kitten

Objective: Elevated aggression and poor intelligence scores occur in children with BLLs (Blood Lead Levels) lower than 10 μg/dL while Pb-exposed cats show increased aggressive behavior with BLLs of 10 μg/dL. This increased aggression in cats may be associated with the development of hyper-spiny neurons observed in the motor cortex, hippocampus and cerebellum of kittens with BLLs<1.2 μg/dL. These results suggest that lead ingestion by kittens might result in learning and behavioral deficits similar to those observed in lead-burdened children. Methods: To test this, kittens were treated (20 mg/kg/day, lead acetate or distil water via esophageal intubation) from Postnatal Day (PND) 1 to 7. At 8 and 10 weeks of age, the kittens were tested in a reversal T-maze, an open-field, and a free-fall test. Results: 8 weeks old Pb-treated kittens showed a delay in learning as demonstrated by a significant higher number of Incorrect Arm Choices (IACs) in the T-maze that returned to control levels in 10 weeks old kittens. No differences occurred between the two groups at 8 and 10 weeks of age in the open-field or free-fall tests. Conclusion: The impairment in the reversal T-maze suggests a Pb-induced delay in learning, which compares favourably with current understanding of delayed learning in Pb-poisoned children.

Neural mechanisms of predatory aggression in rats—Implications for abnormal intraspecific aggression

Our recent studies showed that brain areas that are activated in a model of escalated aggression overlap with those that promote predatory aggression in cats. This finding raised the interesting possibility that the brain mechanisms that control certain types of abnormal aggression include those involved in predation. However, the mechanisms of predatory aggression are poorly known in rats, a species that is in many respects different from cats. To get more insights into such mechanisms, here we studied the brain activation patterns associated with spontaneous muricide in rats. Subjects not exposed to mice, and those which did not show muricide were used as controls. We found that muricide increased the activation of the central and basolateral amygdala, and lateral hypothalamus as compared to both controls; in addition, a ventral shift in periaqueductal gray activation was observed. Interestingly, these are the brain regions from where predatory aggression can be elicited, or enhanced by electrical stimulation in cats. The analysis of more than 10 other brain regions showed that brain areas that inhibited (or were neutral to) cat predatory aggression were not affected by muricide. Brain activation patterns partly overlapped with those seen earlier in the cockroach hunting model of rat predatory aggression, and were highly similar with those observed in the glucocorticoid dysfunction model of escalated aggression. These findings show that the brain mechanisms underlying predation are evolutionarily conservative, and indirectly support our earlier assumption regarding the involvement of predation-related brain mechanisms in certain forms of escalated social aggression in rats.

Evaluation of inciting causes, alternative targets, and risk factors associated with redirected aggression in cats

To identify inciting causes, alternative targets, and risk factors associated with redirected aggression in cats. Case-control study. 19 cats with a history of redirected aggression and 64 cats with no such history. Medical records were reviewed to identify cats evaluated for problems with redirected aggression (case cats), in which the primary inciting stimulus and alternative target of aggression were clearly identifiable. Data obtained from the records and from follow-up interviews included details about the cats and incidents of redirected aggression. Owners of control cats were interviewed via telephone to obtain similar information on their cats. 22 incidents of redirected aggression were reported for the 19 case cats. In 95% of those incidents, loud noises or interactions with other cats were identified as the inciting stimuli. Case cats most commonly redirected their aggression toward the owner, followed by another cat living in the same household. Compared with control cats, case cats were more likely to have a sound phobia but were less likely to be outdoor cats. In addition, case cats were more likely to be from small households (<or= 2 people) than were control cats. In most situations, case cats had adopted a defensive body posture immediately before the incident of redirected aggression, which suggested that the underlying motivation was fear. Fear was likely the most common motivation for redirected aggression in the cats of this report. To reduce the risk of redirected aggression, veterinarians should encourage owners to socialize kittens and habituate them to novel objects and sounds.

Language and the Modulation of Impulsive Aggression

Language and the Modulation of Impulsive Aggression

Differential diagnosis and management of human-directed aggression in cats

In veterinary behavioral medicine and in veterinary neurology, there is an effort to collaborate with different consultants, as seen both in human psychiatry and in human neurology. This cooperation can lead to a complete assessment of any case, to a more holistic collection of information regarding the development of the case, and to a synergetic vision regarding the therapy. In other words, it is essential to understand how behavioral medicine and neurology are linked together to improve diagnosis and therapy process. This review emphasizes the bond between neurology and behavior starting with the neuroanatomic basis of anomalies in veterinary behavioral medicine such as: limbic system, temporal and frontal lobe, pituitary gland, spinal cord, meninges and peripheral nerves. After that, the review deals with some disorders which overlap between neurology and behavioral medicine, and it will conclude by analyzing the differential diagnoses of the neurological diseases and their relationship with behavioral signs.

Brain structures and neurotansmitters regulating aggression in cats: implications for human aggression

1. Violence and aggression are major public health problems. 2. The authors have used techniques of electrical brain stimulation, anatomical-immunohistochemical techniques, and behavioral pharmacology to investigate the neural systems and circuits underlying aggressive behavior in the cat. 3. The medial hypothalamus and midbrain periaqueductal gray are the most important structures mediating defensive rage behavior, and the perifornical lateral hypothalamus clearly mediates predatory attack behavior. The hippocampus, amygdala, bed nucleus of the stria terminalis, septal area, cingulate gyrus, and prefrontal cortex project to these structures directly or indirectly and thus can modulate the intensity of attack and rage. 4. Evidence suggests that several neurotransmitters facilitate defensive rage within the PAG and medial hypothalamus, including glutamate, Substance P, and cholecystokinin, and that opioid peptides suppress it; these effects usually depend on the subtype of receptor that is activated. 5. A key recent discovery was a GABAergic projection that may underlie the often-observed reciprocally inhibitory relationship between these two forms of aggression. 6. Recently, Substance P has come under scrutiny as a possible key neurotransmitter involved in defensive rage, and the mechanism by which it plays a role in aggression and rage is under investigation. 7. It is hoped that this line of research will provide a better understanding of the neural mechanisms and substrates regulating aggression and rage and thus establish a rational basis for treatment of disorders associated with these forms of aggression.

Friendliness to humans and defensive aggression in cats: The influence of handling and paternity

This study was undertaken to examine and reduce the stress and aggressiveness associated with fear of handling in laboratory cats ( Felis sylvestris catus). Thirteen litters of kittens from a specific pathogen-free breeding colony were divided into three treatment groups: two were early weaned, removed from the colony and caged individually with or without handling up to 8 weeks of age, and the third served as a control group, removed from the colony just before testing. Behavior tests measuring degree of friendliness to humans and response to physical restraint were performed at ages 8, 12, 16, and 20 weeks. Serum cortisol concentrations were measured after each test. Results indicate that litter and sire influenced tractability but that handling or individual caging of kittens did not. Posttest serum cortisol concentrations were below normal adult levels in most kittens, including those reacting fearfully during testing and aggressively during restraint, and, therefore, are not a reliable indicator of stress in juvenile cats.

6-Hydroxydopamine-induced aggression in cats: effects of various drugs.

The effects of intracerebroventricular injections (ICV) in the unanesthetized cat of antimuscarinic drugs, ganglionic blocking agents, alpha and beta adrenergic blocking substances, dopamine and 5-hydroxytryptamine (5-HT) antagonists, and an antihistamine on aggressive behavior produced by 6-hydroxydopamine injected similarly was investigated. It was found that atropine, hyoscine, hexamethonium, mecamylamine, yohimbine, phenoxybenzamine, propranolol, practolol, chlorpromazine, haloperidol, antazoline and methysergide exerted virtually no effect on the pattern of aggressive responses evoked by ICV 6-hydroxydopamine. It is thus concluded that the aggressive behavior induced by 6-hydroxydopamine is not related to the release of acetylcholine, norepinephrine, dopamine, histamine or 5-hydroxytryptamine from endogenous storage sites in the brain.

A guide to the literature on aggressive behavior

A guide to the literature on aggressive behavior

6-Hydroxydopamine and Aggression in Cats

The effect of 6-hydroxydopamine (6-OHDA) injected into the cerebral ventricles on behaviour of singly- and group-housed cats was investigated. 6-OHDA in doses of 0.5, 1 and 2 mg was administered every morning for 5 to 8 days. In small doses 6-OHDA in singly- and group-housed cats evoked motor phenomena such as tremor, ataxia, rigidity, weakness and sometimes clonic-tonic convulsions. Occasionally restlessness, irritability and rage were observed. Large doses of 6-OHDA in group-housed cats, after a short latent period (2-3 days) produced aggression which intensified on subsequent injections, and thereafter, on repeated administrations, no longer occurred. The aggression consisted of restlessness, irritability, anger, rage, apprehension, threat, attack, fighting, flight and crying. Of autonomic phenomena mydriasis, dyspnea and sometimes piloerection were observed. The aggression was initiated by the most restless cat, or by disturbing the animals, such as by moving the cage. When 6-OHDA no longer produced aggressive behaviour, motor changes such as tremor, ataxia, rigidity, walking on broad base, weakness with adynamia and clonic-tonic convulsions developed. These latter symptoms were produced by large doses of 6-OHDA in singly-housed cats. In these animals spontaneous signs of aggressive behaviour usually were not observed, although if handled they showed rage, snarling and hissing. When singly-housed cats were kept in the same cage with group-housed animals, the singly-housed cats usually became aggressive. It appears that hyperactivity induced aggression in 6-OHDA-treated cats.

Lithium in the treatment of aggression.

Lithium has become a widely accepted treatment for manic-depressive psychosis. It is dramatically effective for many cases of mania and is useful in the prevention of manic and depressive episodes. Hyperaggressiveness and hypersexuality are frequent components of manic-depressive illness and abate under the influence of lithium. A brief review is presented of the behavioral and biochemical pharmacology of lithium. This documents the inhibitory role which lithium can play in several examples of animal aggressive behavior including pain-elicited aggression, mouse killing in rats, isolation-induced aggression in mice, p-chlorophenylalanine-induced aggression in rats, and hypothalamically induced aggression in cats. The use of lithium to control human aggressive behavior has resulted in controversial findings. In epileptic conditions, improvement has been reported in interseizure aggressivity, but other reports indicate the possibility of increased seizures. Improvement in aggressive behavior in childhood has occasionally been reported as well as in emotionally unstable character disorders in young female patients. Te was a single blind study and the other a large but uncontrolled study. Both studies reported an improvement in aggressiveness as indicated by fewer recorded reports (tickets) for fighting. The final study reported is a study of 12 male delinquents age 16 to 23. They received lithium or placebo for 4 months inside an institution and then a trial of lithium for 1 to 12 months on an outpatient basis. Analysis of results in terms of the number of aggressive antisocial acts showed fewer serious aggressive episodes when the lithium level was between 0.6 and 1 meq/liter than when it was between 0.0 and 0.6 meq/liter. These results must be viewed with caution and are only suggestive since the study was not double blind.

MOTIVATIONAL PROPERTIES OF HYPOTHALAMIC AGGRESSION IN CATS.

MOTIVATIONAL PROPERTIES OF HYPOTHALAMIC AGGRESSION IN CATS.