Field Observations on the Effect of a Mannan Oligosaccharide on Mortality and Intestinal Integrity of Sole (Solea senegalensis, Kaup) Infected by Photobacterium damselae subsp. piscicidaArkadios Dimitroglou1*, Roy Moate1, Thomas Janssens2, Peter Spring3, John W. Sweetman4* and Simon J. Davies1
- *Corresponding Authors:
- John W. Sweetman
Alltech Aqua, 28200 Lixouri
Tel: + 30 6944554446
E-mail: [email protected]
- Arkadios Dimitroglou
Fish Nutrition and Health Research Group
School of Biological Sciences
University of Plymouth, Plymouth, PL4 8AA, U.K
Tel: +30 6973550751
E-mail: [email protected]
Received July 12, 2011; Accepted November 14, 2011; Published November 21, 2011
Citation: Dimitroglou A, Moate R, Janssens T, Spring P, Sweetman JW, et al. (2011) Field Observations on the Effect of a Mannan Oligosaccharide on Mortality and Intestinal Integrity of Sole (Solea senegalensis, Kaup) Infected by Photobacterium damselae subsp. piscicida. J Aquac Res Development S1:013. doi: 10.4172/2155-9546.S1-013
Copyright: © 2011 Dimitroglou A, et al. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.
This study was conducted in order to investigate the effect of a mannan oligosaccharide (MOS) on the intestinal morphology of sole (Solea senegalensis, Kaup) reared under commercial conditions. The dietary inclusion rate for MOS was 0.4% and it was used either alone or in combination with a vaccination regime against bacterial diseases (Pasteurella spp. and Vibrio spp.). One week after the start of the experimental period, a natural outbreak of pasteurellosis, caused by Photobacterium damselae subsp.piscicida,occurred in all the groups of fish.A two-way ANOVA showed that only MOS supplementation reduced fish mortality by ca. 8% (P = 0.050). Additionally, light microscopy examination of the intestine revealed that MOS supplementation significantly increased the mucosal folding by 29% (P = 0.016) in the anterior intestinal region and by 33% (P = 0.002) in the posterior intestinalregion. Scanning electron microscopy demonstrated that both MOS supplementation and vaccination significantly increased microvilli density on the enterocyte surfaces in the anterior intestinal regionby 13% (P = 0.028) and 30% (P = 0.001) respectively. In the posterior intestinalregion neither MOS supplementation nor vaccination significantly affected the microvilli density (P = 0.005).The present study suggests that dietary MOS supplementation protects the intestinal morphology of infected sole and hinders the development of pathogenic infection, possibly by binding with Photobacterium damselae subsp. piscicida, resulting in reduced mortality of infected fish.