Growth and Dietary Efficiency of Mulberry Silkworm (Bombyx mori L.) Under Various Nutritional and Environmental Stress Conditions
V.K. Rahmathulla, V.B. Mathur and R.G. Geetha Devi
Central Sericultural Research and Training Institute, Mysore, India
corresponding author:
ABSTRACT
The fifth instar larvae of bivoltine silkworm race (CSR2 x CSR4) were reared under various nutritional and environmental stress conditions to determine growth and dietary efficiency. The data were compared with a control, which was provided with standard feeding and reared under optimum temperature and humidity. Parameters like larval weight, silk gland weight, cocoon weight, shell weight and nutritional indices parameters like ingesta, digesta, approximate digestibility percentage and reference ratio were significantly higher in the control. Most of these parameters were significantly least in larvae reared under high temperature and low humidity. However, most of the feed conversion efficiency parameters and ingesta and digesta required to produce one gram of cocoon and shell were higher in treated batches. This may be due to physiological adaptation of the larvae under different stress conditions.
INTRODUCTION
The silkworm, Bombyx mori is a poikilothermic insect and it is the main source for production of silk. Environmental factors such as temperature, humidity, light, air, feed quality as well as quantity have intimate influence on its growth and development. The consumption and utilization of food in insects facilitate the understanding of the adaptability of insects to the environment. Food consumption and utilization is influenced by various conditions which influence the crop, the most important are the atmospheric temperature and humidity . . . . . .
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