A specific composition of 1-Monoglycerides of Short and Medium Chain Fatty Acids (from C3:0 to C12:0), available on the market under the commercial name SILOhealth 108, proved to exert a selective antibacterial action in vitro against pathogenic bacteria like Y. ruckery, F. psycrophilum, V. Alginolyticus, V. harveyi and T. maritimum independently from the environmental pH. In the in vitro trials the Minimum Inhibitory Concentration of SILOhealth 108 against these bacteria ranged in fact from 0.01% to 0.1% at both pH values: 4 or 7, which indicates that the composition is antibacterial also in the environmental conditions of the organs of aquatic species like gut and liver. Beneficial Lactobacillus was not inhibited by SILOhealth 108. Since 1-Monoglycerides possess emulsifying properties, they are dispersed in the liquid medium of the digestive apparatus and are expected to reach in vivo the deeper tracts of the GIT and to permeate biological districts like liver and hepatopancreas. Furthermore, some 1-Monoglycerides contained in SILOhealth 108 proved to perform a positive angiogenic effects on the body internal tissues (Dobson et al.,1990). As consequence, the formation of new blood vessels on microvillus is stimulated, the nutrient transport in bloodstream is increased, the tight junctions expression and the reparation of lesions caused by bacteria or dietary intolerances is enhanced in GIT.
1-Monoglycerides contained in SILOhealth 108 significantly enhanced the feed efficiency in see bream in experimental conditions. In field, in presence of severe bacterial challenge, SILOhealth 108 strongly decreased the mortality and enhanced the fish growth. 1-Monoglycerides can be considered as a promising approach to reduce the antibiotics usage: direct and selective antibacterial action, positive impact on gut integrity, stimulation of microvillus vascularisation and increase of nutrient absorption.