Regular handling early in the nursing period eliminates fear responses toward human beings in wild and domestic rabbits

The effect of early handling has been of special interest as there is accumulating evidence that the experimenter might be considered as a predator by the animals, resulting in an undesirable level of fear in experimental studies. The aims of the present study were (a) a systematic investigation of the effect of regular daily handling on the fear reaction toward human beings both in domestic and in wild type rabbits, (b) to measure the long‐term consequences of the handling, (c) to investigate whether the effective handling is linked to the nursing period, and (d) to see whether the effectivity of handling is confined to a sensitive period in the rabbit. We found that both domestic and wild rabbits are sensitive to human handling, especially when it is performed near the time of nursing. There was a sensitive period, the 1st week postpartum, in the effectiveness of handling. The animals handled in the sensitive period readily and repeatedly approached the observer, indicating the lack of fear. The effect of handling seemed long‐ lasting as handled females raised to adulthood were superior to nonhandled individuals in their breeding performance. These results indicate that reduced fear of humans can be achieved via handling and this might be a prerequisite for studying the unbiased behavior of animals via direct observation. © 2000 John Wiley & Sons, Inc. Dev Psychobiol 36: 78–87, 2000