Transportation of laboratory rodents unavoidably causes stress. Nevertheless, very little is known about the effects of transportation and how long it takes for the animal to recuperate. In the present study, we investigated physiological and behavioral parameters before and after transportation in both transported and nontransported animals. We took blood samples to analyze plasma corticosterone and creatine kinase, and performed physiological measurements by means of telemetry, measuring heart rate, blood pressure, and activity. Behavior was measured by means of home cage observations. This study revealed that plasma corticosterone levels increased at least up to 16 days after transportation, blood pressure and heart rate showed a lasting decrease after transportation, grooming increased, and social interactions and locomotor activity decreased after transportation. With these data we demonstrate that there is a long-lasting effect of transportation on physiological and behavioral parameters. Our results show that the stressful impact of transportation embraces all parts of the procedure, including for example the packing of the animals. Researchers must be aware of this impact and provide a sufficient acclimatization period to allow for the (re-)stabilization of parameters. Insufficient acclimatization periods endanger not only the reliability of research results but also the welfare of the animal used.

Simple SummaryThis study in laboratory rodents shows a sex specific effect of breeder to research facility transfer on several physiological parameters, such as heart rate and blood pressure. We recommend at least 8 days of acclimatization time after transfer in male rats and at least two weeks in female rats, before using these animals in research.AbstractMost laboratory animals used in research are vendor-bred and transferred to research facilities. Transfer procedures might have considerable and unintended effects on research results. In the present study we compared physiological and behavioral parameters before and after external and internal transfer, as well as between transferred and non-transferred Wistar rats. The impact of both external and internal transfer on body weight, plasma corticosterone levels, heart rate, blood pressure, and locomotor activity was studied in both male and female Wistar rats, taking into account the sex differences in stress responsivity. External transfer was found to decrease body weight, increase plasma corticosterone, increase activity, increase heart rate in female rats, but decrease heart rate in male rats. Parameters showed differences between the sexes and light phases. This study shows that acclimatization after transfer is sex-specific and researchers should take the sex into consideration when determining the acclimatization period. It is recommended to allow for acclimatization of at least 8 days in males and two weeks in females after external transfer and timely (2 days before starting experiments) transfer the animals internally to the testing room.

Simple SummaryThis study measured effects of transfer on body temperature, stress hormone levels, body weight, behavior and water and food intake in rats. Environmental temperature strongly affected body temperature of rats and needs to be controlled. Male rats need to habituate for at least one week, females for two weeks after transfer.AbstractTransfer from the breeding facility to a research facility is a stressful event for laboratory animals. Heat stress has been reported to constitute one of the major concerns during transport of animals. This study measured ambient and body temperature, corticosterone and glucose levels, body weight, behavior and water and food intake before, during and after transfer in Wistar rats. Decreased body weight, water and food intake were observed on the day of transfer in rats. Environmental temperature strongly affected body temperature of rats and needs to be controlled. Male rats need to habituate for at least one week, females for two weeks after transfer.