Effects of solvent extractions, heat treatments and added cholesterol on Sesbania sesban toxicity in growing chicks

Abstract

The objectives were to test the hypotheses that: (1) dry heat treatment destroys the Sesbania sesban toxicant; (2) the toxicant can be inactivated by binding to cholesterol; (3) or by autoclaving with ammonia; (4) to assess the solubility of the S. sesban toxicant in cold, warm and hot water, ethanol and diethyl ether. Three groups of 4–5-day-old male Hubbard chicks were assigned to each of 16 diets for 2 weeks. Diets and water were offered ad libitum. Diets contained: 10% S. sesban (S); dry-heated S; S + 1% cholesterol; S + 2% cholesterol; maize and soya-bean meal control diet (C) + water residues; C + water extracts; C + ether residue; C + ether extract; C + ethanol residue; C + ethanol extract; S autoclaved with NH 4OH. Both the hot water extract and the residue had some limited toxic activity. Diets containing all other S. sesban extracts were not toxic. All other residues of S. sesban extracts were as injurious as the untreated material. Dry heat treatment and ammonia autoclaving improved growth by 174% and 229% relative to untreated S. sesban, respectively. Adding 1 or 2% cholesterol to 10% S. sesban diets increased growth by 264%. A saline extract of S. sesban leaves exhibited hemolytic activity equivalent to 0.71% saponins on a 100% dry matter basis.