Food Consumption and Utilization Efficiency in Samia ricini Donovan Reared on Ricinus communis, lin. Leaves Supplemented with Cyanobacteria

Abstract

Food consumption and conversion efficiency of eri silkworm Samia ricini Donovan were studied during 4 th and 5 th larval instars by feeding castor leaves fortified with 100, 200, 300, 400 and 500 ppm concentrations of aqueous extracts of cyanobacteria Anabaena variabilis. The nutritional indices viz., ingesta, digesta, approximate digestibility (%), reference ratio and efficiency parameters like ECI and ECD were recorded which were significantly high at 400 ppm concentration treated batches of 4 th instar larvae over control batches. The decline in nutritional efficiency parameters of 5 th instar treated larvae might be due to higher utilization of the digested food for metabolic activities. Significant difference of ECI to cocoon % and non-significant difference of ECD to cocoon% and shell were observed between the treatments and control. Cyanabacteria feed supplement contains antibiotic and nutritions factors which has reflective effect on the biological parameters in eri silkworm and therefore has greater application in commercial eri silkworm rearing. also (Bajpeyi et al ., 1991). Probiotics are the live microbial feed supplements which beneficially affect the host by improving the microbial balance (Yeung et al ., 2002). The microbes, Lactobacilli and Bifidobacteria, are gram + ve bacteria producing lactic acid and extensively studied to improve cocoon characters in B.mori L (Masthan et al ., 2010). Oral administration of mulberry leaf and castor leaf supplemented with single cell protein ‘spirulina’ (Blue green algae) as a feed to respective silkworms Bombyx mori L (Venkataramana et al ., 2003) and Samia cynthia ricini Boisduval (Jayaprakash et al ., 2005) was found to be effective in enhancing the larval and cocoon characters in mulberry silk worm. The antiviral protein of spirulina platensis Abstract