Bacillus mycoides Improves Health of Gastrointestinal Tract in Marron (Cherax cainii, Austin 2002)

Abstract

The present study examined the health status of the gastrointestinal tract (GIT) in marron after a two-month feeding trial with a diet supplemented with host origin, Bacillus mycoides. Two groups of marron were fed with either a basal diet or probiotic added at 108cfu/g of feed. Microbial density, microvilli length and number, intestinal epidermis layer morphology and hepatopancreas indices of weight and moisture content were evaluated. Supplementation with B. mycoides in marron feed significantly improved intestinal bacterial density (4,007±121 million cfu/g of GIT) compared to basal diet fed marron (723.7±45.2 million cfu/g of GIT). Microvilli density (per 100 µm2) was also significantly higher (10.50±0.25 µm) compared to 5.71±0.24 in basal diet fed marron. Significantly higher villous length (4.93±0.11 µm) was observed in probiotic fed compared to basal diet fed marron (3.91±0.18 µm). The intestinal epidermis layer of probiotic fed marron showed increased folding and thickness compared to basal diet fed marron. Higher hepatosomatic indices (Hiw) and low moisture content (HM%) in probiotic fed marron indicated efficient functioning of the healthy gut. The present study suggests that supplementing host origin customised probiotic in feed improves gut health as measured by microbial density, microvilli length and number, intestinal epidermis layer and hepatosomatic indices.