Axenic Ovarial Explants from the Marine Nematode Deontostoma californicum on Culture Media.

The gonads of Deontostoma californicum were isolated from the organismal environment by dissection. In an attempt to approximate the in vivo condition and to maintain in vitro architecture and function ten media recommended for the culture of insect cells or organs were tested. The media were prepared in two series: one according to published recommendations and the second substituting filtered seawater for the inorganic salts and distilled water. Media were prepared as both liquid and gel (agar) with and without antibiotics. Whole animals and eggs were placed on the same culture media series as the ovarial explants. Ovarial explant reaction was divided into those which supported the entire gonad and those which supported the ovary or ova-containing oviduct. Seawater preparations of Samia and Grace culture media were outstanding for support of the entire explant. Eggs underwent their greatest development in seawater without antibiotics. Prolonged survival of whole animals took place only in those media (A-l, C-G, 26c, 199, Mosquito, and Media B) in which the inorganic salts and distilled water were replaced by filtered seawater. The results demonstrated that those conditions suitable for adults on culture media are not necessarily suitable for eggs, larvae, or tissue explants.