Preliminary Experiments with a Defined Culture Medium for LarvalFasciola hepatica

Abstract

A defined medium is described as a basis forin vitroculture work with larvalFasciola hepatica. This medium, termed BCM, can be quickly made up by using a system of stock solutions. BCM contains inorganic salts, glucose, amino acids, vitamins and antibiotics, but no lipid or proteins. Rediae can be dissected from infected snails for culture, but many appear to be contaminated with bacteria. Large rediae cannot survive in BCM but free immature cercariae can complete their final maturationin vitro. This final maturation, from the 30th to the 35th day after miracidial penetration of donor snails, includes tail growth and appearance of body pigmentation. Cercariae maturedin vitroencyst successfully when transferred from BCM to water. Small rediae survive in BCM for 5 days, but show no growth or development measured as dry weight and total nitrogen.