ABSTRACT
The management of dog behavioural problems requires the expertise of professionals such as the veterinary behaviourist. Clinical assessment of behavioural disorders allows the veterinary behaviourist to formulate a diagnosis and prescribe a behavioural and/or pharmacological therapy. The objective of such therapy is to produce a stable change in the perception of a stimulus and the resulting emotion, leading to the correction of the behavioural problem. It may be crucial to evaluate the subject's pathological state in response to the observed symptoms in order to identify the functional impairment of the pivotal neurotransmitter systems involved in the disorder. This allows selecting a suitable pharmacological treatment. In order to implement behavioural therapy, the veterinary behaviourist collaborates, where necessary, with a team of qualified canine trainers.
Subject(s)
Behavior Therapy/methods , Behavior, Animal , Dog Diseases/psychology , Mental Disorders/rehabilitation , Mental Disorders/veterinary , Affective Symptoms , Animals , Dog Diseases/drug therapy , Dog Diseases/therapy , Dogs , Emotions , Mental Disorders/drug therapy , Psychotropic Drugs/therapeutic use , Veterinarians , Veterinary Medicine/ethicsABSTRACT
In mammals ghrelin has a diverse range of effects including stimulation of gut motility but although present in teleost fish its effects on motility have not been investigated. The present study used bioinformatics to search for fish paralogues of the ghrelin receptor and the closely related motilin receptor, and investigated the effects of ghrelin and motilin on gut motility in zebrafish, Danio rerio. Fish paralogues of the human ghrelin and motilin receptor genes were identified, including those from the zebrafish. In addition, a third gene was identified in three species of pufferfish (the only fish genome completely sequenced), which is distinct from the ghrelin and motilin receptors but more closely aligned to these receptors relative to other G-protein coupled receptors. Immunohistochemistry demonstrated strong ghrelin receptor-like reactivity in the muscle of the zebrafish intestine. In isolated intestinal bulb and mid/distal intestine preparations, ghrelin, motilin, and the motilin receptor agonist erythromycin all evoked contraction; these responses ranged between 9% and 51% of the contractions evoked by carbachol (10(-6) M). There were some variations in the concentrations found to be active in the different tissues, e.g., whereas motilin and rat ghrelin caused contraction of the intestinal bulb circular muscle at concentrations as low as 10(-8) M, human ghrelin (10(-8) to 10(-6) M) was without activity. Neither ghrelin (10(-7) M) nor erythromycin (10(-5) M) affected the contractions evoked by electrical field stimulation. The results suggest that both ghrelin and motilin can regulate intestinal motility in zebrafish and most likely other teleosts, and are discussed in relation to the evolution of these regulatory peptides.
