Fetal bovine serum and virus, endotoxin, haemoglobin, IgG and total protein assays. Ethical questions have been raised regarding the blood collection process due to the potential suffering caused to the fetus. Although anoxia or active slaughter could be used to induce unconsciousness or death prior to serum harvesting, exposure of live unborn calves to oxygen can cause them to gain awareness before being killed, resulting in active debate about the ethics of harvesting serum. Fetal bovine serum is commercially available from many manufacturers, and because cells grown in vitro are highly sensitive, customers usually test specific batches to check for suitability for their
Blood, toil, tears, and sweat are "It [poetry] is forged slowly and painfully, link by link, with blood and sweat and tears" (Lord Alfred Douglas, 1919), "Blood, sweat, and tear-wrung millions" (Lord Byron, 1823), and "...mollifie/ It with thy teares, or sweat, or blood" (John Donne, 1611). In Latin, Cicero and Livy had used the phrase "sweat and blood". "We are in the preliminary stage of one of the greatest battles in history... That we are in action at many points—in Norway and in Holland—, that we have to be prepared in the Mediterranean. That the air battle is continuous, and that many preparations have