Behaviour of golden hamsters (Mesocricetus auratus) - Vetsuisse ...

Procedure and MeasurementsProcedureIn week 0, at weaning, hamsters were approximately 4 weeks of age. During theexperiment they were weighed repeatedly (Fig. 1). The body length (snout to tip oftail) was measured before termination on the anaesthetized animal, which wasstretched out on a ruler. The body condition of the hamsters was calculated as bodyweight in proportion to body length (body weight in week 13/length 3 ), which is adegree of fat tissue. Hamsters were video-taped, between 15:30 and 18:30 p.m., i.e.2:30 hours after dawn (Fig. 1). In weeks 11 and 12 each hamster was stressed ontwo following days by shaking the cage, chasing, handling, habitation in a smallcardboard box for 30 minutes and loud music for three to five minutes. Additionallyon the first day of stress half of the litter was changed, while on the second day aconfrontation with another hamster was performed. Thirteen weeks after weaninghamsters were decapitated after Isoflurane-anaesthesia. Blood was collected andsent to Alomed, Analytical Laboratory Dr. W. Müller, (Germany), for analyses ofcorticosterone, cortisol and ACTH. Organs (adrenals, heart, liver, kidney and spleen)were weighed and checked for differences in the 4 cage sizes. Special attention wasgiven to the weights of adrenals as an indicator of stress. Gastric mucosa wascontrolled for ulcers. All brains were examined for hydrocephalus internus.9