The Foundation for Biomedical Research, an advocacy and lobbying organization for biomedical industries has been dumbing down the public discourse around the use of animals in medical research with bill-boards in several cities. ABCNews has the story http://abcnews.go.com/Health/Drugs/animal-research-billboards-pit-cute-girl-lab-rat/story?id=13371007
Now, one might say that this does not make an argument and so cannot argue fallaciously. As their spokesperson (roughly) says in the article, they are just getting people to "ask the question" and "think about why doing animal research is important." And that might be fair enough, even if it seems, perhaps, a bit disingenuous. But, it seems to me, even if we grant this, doing so should lead us to see that they expect us to infer something from our answer to this question.
Perhaps it's just:
C: Killing the rat to save the little girl would be a good thing.
But, it seems unlikely that they are merely interested in agreement to such a limited conclusion. Presumably the girl and the rat represent a general claim about the value of the lives of cute little girls and rats. And, as an advocacy group, which lobbies against further restrictions on the use of animals in biomedical research (such as considering rats "animals" under the Animal Welfare Act, I believe) and defends research that kills and causes animals to suffer for possible medical benefits, it seems likely that they want us to infer something further from this premise. Perhaps,
P1: It would be better to save the girl than the rat.
C: The use of animals in research generally is good.
But, if someone were to infer that broader claim, as I suspect, the FBR would like, they would seem to be reasoning fallaciously.
The argument might also be taken as an argument from inconsistency:
P1: You hold that the use of animals for research is morally problematic. (70% of Americans do according to FBR).
P2: You would save a girl's life rather than a rat's life.
C1: Your belief in P1 is false
or, C2: You do not have good reason to hold your belief in P1
or, C3: You are an unreliable judge of the moral issue.
This is a better argument, and takes the form of a subjunctive tu quoque, of the fallacious variety–which conclusion should be drawn is unclear, but all of them seem non sequiturs.
On our analysis of subjunctive tu quoque's, the question is whether
P3: Your judgment in P2 is more relevant for judging the moral issue than whatever grounds you have in P1.
If this premise is supplied the argument looks less logically awful (for C2 at least), but P3 is unlikely to be true, making the argument at best unsound. Further as I noted above, it seems likely that the FBR would like the viewer to draw C1, which does not follow from the premises even with P3 supplied.
There are other things to say about the logic of the implicit arguments here, and my charity is running out. One might think, at the least, that it is curious that some would want to defend scientific research with bad arguments, but perhaps that's just my out-dated enlightenment views of science surfacing.