Autoregressive technique in length growth modelling of two Indian major carp, Catla catla (Hamilton) and Labeo rohita (Hamilton), reared under two holding conditions

Abstract

An autoregressive analysis was performed on data from an investigation of the velocity and acceleration of the day‐to‐day length increments of two Indian major carp, Catla catla (Hamilton) and Labeo rohita (Hamilton), hatched in artificial (Chinese‐style hatchery) and semi‐natural (improvised pits) holding conditions. The autoregressive model, which was capable of providing short‐ and long‐term predictions, was tested in parallel with a time regressive model and an instantaneous growth rate model. The estimate simulating short‐term predictions was found to describe the data more efficiently than the other estimates of the models. Product‐moment correlations comparing the two holding systems revealed no source‐specific variation of growth between the species. However, the significant length velocity correlation suggests that the artificial system has greater efficacy.