In common with the practice at many other institutions, the animal facility at Great Eastern University did not include neonatal mice in the census count until they were weaned. It was also common for investigators to euthanize transgenic mice that did not have the needed genotype for a particular research project. These two practices in combination provided an opportunity for some researchers to avoid paying per diem charges on their superfluous transgenic mice by euthanizing them before they were weaned. Of course, because the animals were never counted on the census, they also were never subtracted from the number of animals approved by the IACUC for that study. This chain of events never raised any eyebrows at Great Eastern until the Committee's unaffiliated member nonchalantly asked about the need to count the tadpoles that were part of another study.
“I was wondering,” said Pat Waite, “if we're supposed to count tadpoles as 'animals' or if we're supposed to wait until they pretty much change into frogs?”
“That's a good question” replied Larry Cristofini, the IACUC Chairman. “Since tadpoles are, in the IACUC's opinion, self-sustaining animals, we have always counted them as soon as they are capable of feeding themselves. In other words, similar to what we do for zebrafish fry.”
“Okay,” said Waite, “but that leads me to another question. If we count tadpoles as soon as they are capable of feeding themselves, how come we don't count mouse pups, including transgenic pups, as soon as they are born? They're perfectly capable of nursing their dams at that time. Not only that, but I've been told many times that pups start eating solid food by themselves before they are weaned. Don't we have two standards? Shouldn't we really put mouse pups on the census as soon as they're born?”
“Don't worry about it, Pat” said Cristofini. “We've always done it this way and we've never had any complaints from OLAW [Office of Laboratory Animal Welfare], nor have I ever seen anything that OLAW has written to contradict what we do. Not only that, but when we have our AAALAC [Association for Assessment and Accreditation of Laboratory Animal Care International] site visits, nobody has ever questioned us. I think we can take that to mean that we're in compliance with federal regulations.”
Is Great Eastern in compliance with their method of accounting for neonatal mice, or are OLAW and AAALAC just not making an issue of a common practice?
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Silverman, J. Should you count your mice before they're weaned?. Lab Anim 35, 15 (2006). https://doi.org/10.1038/laban0106-15a
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DOI: https://doi.org/10.1038/laban0106-15a
