I hard disagree that pilot projects and results from data with technical issues should be published. There is a real cost to write-ups (time). Pilot projects usually are done just to prove feasibility of a protocol, and data retrieved from experiments with technical issues is likely noise. This could include inaccurate measurements, cross-contamination, etc. Taking the time to write and publish all the junk is, frankly prohibitive. I do think null-results should be publishable, however.
The title is a bit of click bait also: The animals are not missing. Make a request of the relevant Institutional Review Board.
Are any of you voting my comment down actually scientists?