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
Clotting time Clotting time Clotting time is the time required for a sample of blood to coagulate in vitro under standard conditions. There are various methods for determining the clotting time, the most common being the capillary tube method. It is affected by calcium ion levels and many diseases. Normal value of clotting time is 8 to 15 minutes. For the measurement of clotting time by test tube method, blood is placed in a glass test tube and kept at 37° C. The required time is measured for the blood to clot. There are several other methods, including testing for those on