I support Gooding's assessment that the IACUC wants to “make sure that [Rosen] is going to use the smallest number of animals that can give you scientifically acceptable results.” Let's see if we can get Rosen to see (at least a couple of) the 3Rs of our ways.

It appears from this example that Rosen would like to use two groups of rabbits for this experiment, and both groups would be subjected to the same major surgical procedure. If the only difference between the groups is that one will be used to visualize grossly the anastomoses (via endoscope) while the other will be serially euthanized for histopathological exam, then the IACUC is serving its function to identify the terrific opportunity for Rosen to both reduce his rabbit numbers and achieve the same scientific aims.

Although Rosen correctly interpreted the language in the AWA regarding the IACUC's role of not setting the standards for scientific design, his biostatistician and/or veterinarian should have raised this issue before it even went to the Committee. Using one group of animals, Rosen can do the surgery, examine the rabbits endoscopically, and then serially euthanize each animal for histology. In this repeated-measures design, he will adequately correlate the two different methods of observation for each subject. His current design will provide no correlation between those undergoing endoscopy and those viewed histologically. I think Rosen believes he can get that correlation with two groups. He just needs guidance.

The IACUC probably identified this flaw and, championing the use of fewer animals, would like a justification for using two groups. If Rosen can justify that the endoscopic procedure will somehow alter the colon histologically, he may be able to succeed in his proposal as designed, but if the colon is damaged or altered by this method, then why not seek a refinement for the rabbit? He can instead do CT or MRI scans on his rabbits. He could consider ultrasound. In this manner, he has only to anesthetize his rabbits for restraint, not for analgesia for the potential pain or discomfort that may be associated with insufflation of the colon.

Rosen has a friend in Gooding, who is really trying to get Rosen to see the light. It's a committee that decides, not one individual, and if the Committee saw an opportunity to implement any of the 3Rs (especially when the same scientific goals will be achieved), then they are justified in asking Rosen to reconsider his experimental design.