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, Sweat & Tears 4 band's cohesion seemed to be disintegrating. Although the album scraped the Top Ten briefly and went gold, it marked the end of BS&T's period of wide commercial success on records." Music critic Robert Christgau's only comments were "Aww-shuck! heck." Additional musicians Album - Billboard (United States) Singles - Billboard (United States) Blood, Sweat & Tears 4 Blood, Sweat & Tears 4 is the fourth album by the band Blood, Sweat & Tears, released in 1971. It peaked at number 10 on the Billboard Pop albums chart. The band invited former member Al Kooper to contribute the song "John the Baptist