Use of tricyclic antidepressant Amitriptyline in treatment of a cat with interspecies aggression against humans: clinical report

The treatment effect of Amitriptyline on the cat with aggression against humans was shown. Before the treatment the cat attacked on the members of family, bit them, demonstratively threatened, hissed. During the first weeks the cat obtained the preparation with the fodder twice a day at the dose 0.5 mg/kg with the interval 12 h. During the therapy the following was noted: 1) the effect of the overdose, when one-time dose was 2 mg/kg. The mydriasis, dyspnoea, decrease of the aggressive behavior intensity were noted. The sedative effect of amitriptyline was clearly shown; 2) the effect of the sharp cancellation of the drug. The recurrence of aggression was observed. The cat attacked on the member of family and bit him; 3) the effect of smooth cancellation of drug. The weak sedative influence of drug on the cat behavior was noted. This clinical case showed that Amitriptyline can be used in the treatment of cats with hyper-aggression against humans.

Interspecific aggression among parapatric and sympatric songbirds on a tropical elevational gradient

Interspecific competition is hypothesized to be a strong force that sets species range limits and drives parapatric distributions of closely related species on tropical mountains. Yet, experimental evidence that competition drives spatial segregation of closely related species on elevational gradients is rare. To test whether competition limits elevational ranges of tropical songbirds, we conducted reciprocal playback experiments on 2 pairs of species with adjacent but nonoverlapping (parapatric) distributions and 1 pair of sympatric species. We found asymmetric interspecific aggression in one parapatric pair (Pycnonotidae) and a complete absence of interspecific aggression in the other (Zosteropidae). We also found asymmetric interspecies aggression in a pair of sympatric flycatchers (Muscicapidae). Our results indicate that interspecific aggression may set range limits in some cases, but it is not a prerequisite for parapatry. Furthermore, the presence of interspecific aggression between co-occurring relatives suggests that while competition may play a role in limiting species distributions, interspecific aggression alone is not sufficient evidence to assert that competition is the primary driver of parapatric distributions.