Morphological changes and allometric growth in hatchery-reared Chinese loach Paramisgurnus dabryanus (Dabry de Thiersant, 1872)

摘要

The length-weight relationship and allometric growth patterns of hatchery-reared Chinese loach,Paramisgurnus dabryanus (Dabry de Thiersant,1872),were determined from hatching to 60 days after hatching.A best power model was estimated for the length-weight relationship during the early life stages.Positive allometric growth for the head segment,trunk length,tail length and eye diameter was also found in the early life stages,while body depth,tail depth,tail fin length,pectoral fin length and barbel length displayed a negative coefficient.During the subsequent early developmental stage,the growth coefficients showed a clear and common tendency towards isometry for all measured body ratios.The allometric growth changes in Chinese loach during the early stage are possibly the result of selective organogenesis directed towards survival priorities.