Hatching Fish-When Should Animal Tracking Begin?

The National Institutes of Health: Final Report to Office of Laboratory Animal Welfare (OLAW) on Euthanasia of Zebrafish (2009) established for the first time a policy for the developmental stage at which zebrafish would qualify for animal oversight by OLAW interpretation of Public Health Service policy. This policy established the time point based on a comparison with chicken/avian hatching. For zebrafish, this is 3 days postfertilization (dpf). This is in contrast to the traditional time established within the community as 7 dpf. There are significant implications for this policy not the least of which is the demand to account for all embryo and larvae at all stages. This narrative provides a situational context based on a synthesis of real experience with this policy. The hope is that it provides a starting point for a community conversation on the hatching time point as the appropriate established policy for the future.