Technological Stress Prevention to Nutria (Myocastor coypus)

Animal grouping, groups restructure, changing the docks and various technological operations causes disorders to the nutria manifested by aggressive behaviour. Tranquilizers prevent the stress and lower the catecholamine’s levels. In a number of 300 individuals grouped into four groups (one control group and three experimental groups) was surveyed the effect of Promazine (20 mg/kg, experimental group I), Diazepam (15 mg/kg, experimental group II) and Nitrazepam (15 mg/kg, experimental group III) administration for preventing stress and aggression resulted from various technological operations. Grouping animals and groups restructure generates behaviour disorders manifested by acute aggression, maximum within 4-6 hours and maintained for 24-36 hours. In the three experimental groups the intensity and frequency of aggressive acts decreased near zero, with greater efficacy in experimental group II and III. Duration of cataleptic effect was 3-7 hours (experimental group I), and 8-12 hours in the other two experimental groups, covering the period in which aggression is greatest. Waking up is done in 2-3 hours, moment at which the behaviour is almost that of an old group. The negative consequences of groups restructure, transport and other technological disturbing measures can be prevented by animal’s tranquilization, and the three substances investigated had an efficient preventive effect.