Growth in the Australian freshwater crayfish, Cherax destructor Clark, under laboratory conditions

Abstract

Small (0.08 to 6.1 g) crayfish were grown at 26ºC under three treatments: held individually and fed 3% or 10% of body weight per day, or held communally and fed the higher ration. Moult increments, expressed as length or weight increment (%), were smaller and intermoult periods were longer in the crayfish held communally or, particularly, in crayfish fed low rations; this resulted in lower growth in these treatments. Crayfish from three geographically discrete populations held individually and fed the higher ration showed relationships between log moult increment in weight and log premoult weight; further, the length of the intermoult period increased with size for these populations. Models for average growth showed that C. destructor may grow from 0.1 g to 40 g in approximately 230 days. Growth may have been suppressed in the culture system because of the size of containers, the entirely artificial diet and the variable water quality.