Blood
Unlike mammals, horseshoe crabs do not have hemoglobin in their blood, but instead use hemocyanin to carry oxygen. Because of the copper present in hemocyanin, their blood is blue. Their blood contains amebocytes, which play a role similar to white blood cells for vertebrates in defending the organism against pathogens. Amebocytes from the blood of L. polyphemus are used to make Limulus amebocyte lysate, which is used for the detection of bacterial endotoxins.
Harvesting horseshoe crab blood involves collecting and bleeding the animals, and then releasing them back into the sea. Most of the animals survive the process; mortality is correlated with both the amount of blood extracted from an individual animal, and the stress experienced during handling and transportation. Estimates of mortality rates following blood harvesting vary from 3% to 15%.
Read more about this topic: Horseshoe Crab
Famous quotes containing the word blood:
“The cloud was so dark that it needed all the bright lights that could be turned upon it. But for four years there was a contagion of nobility in the land, and the best blood North and South poured itself out a libation to propitiate the deities of Truth and Justice. The great sin of slavery was washed out, but at what a cost!”
—M. E. W. Sherwood (1826–1903)
“I confess my belief in the common man.... The man who is swimming against the stream knows the strength of it.... The man who is in the melee knows what blows are being struck and what blood is being drawn.”
—Woodrow Wilson (1856–1924)
“A Spirit free, to choose for my own share,
What sort of Flesh and Blood I pleas’d to wear,
I’d be a Dog, a Monkey or a Bear,
Or any thing, but that vain Animal,
Who is so proud of being rational.”
—John Wilmot, 2d Earl Of Rochester (1647–1680)