MAINTENANCE OF ASCARIS LUMBRICOIDES IN VITRO: A BIOCHEMICAL AND STATISTICAL APPROACH

Abstract

The anaerobic carbon dioxide production of minced ascaris muscle decreases markedly when worms are kept in vitro for 3 days. Using this gas production as an index, and a factorial design, the effects of nitrogen, oxygen, carbon dioxide, antibiotics, vitamins, amino acids, glucose, potassium, and ammonium ions were investigated. For this study the worms were kept in media which were changed every 3 hours and the gaseous phases were maintained by bubbling gas continuously through the media. Under these conditions 20% oxygen was extremely toxic but carbon dioxide (5%) provided some relief from this effect. Even 5% oxygen caused more decrease in the index than did nitrogen alone, but this was not true when a mixture of amino acids and glucose was present. Ammonium ions had a beneficial effect in nitrogen but a detrimental effect in the presence of 20% oxygen. A high potassium ion concentration (24 mM) was detrimental in the absence of carbon dioxide but appeared to enhance the beneficial effects of carbon dioxide.