Obviously. Are you really going argue that humans aren't worth more than crabs? Would you genuinely let your own family members suffer a preventable disease because you didn't want to injure a crab?
We seem to be a species that likes to destroy entire environments and extinguish other species. We can always say, "but it was for our well-being".
Where do you draw the line, then? Some people live a vegan lifestyle (I don't), some will not wear fur, or like to buy products that are tested on animals - or other products that are mass produced by wiping out entire forests for a mono crop.
To further the philosophical debate, what if you apply the same emotional attachment you have on a loved one, to the animal? Would you harvest an organ from your family dog, if it meant your brother had a 50% chance of living? What if the dog had a 50% chance of surviving the operation to remove the organ? What if those chances were greater or less?