Effects of dietary supplementation with encapsulation form of Enterococcus faecium on growth performance, feed utilization, intestinal microbiota and related health criteria for rainbow trout (Oncorhynchus mykiss Walbaum, 1792)

Abedian Amiri, Armin; Azari Takami, Ghobad; Afsharnasab, Mohammad; Razavilar, Vadood

Effects of dietary supplementation with encapsulation form of Enterococcus faecium on growth performance, feed utilization, intestinal microbiota and related health criteria for rainbow trout (Oncorhynchus mykiss Walbaum, 1792)

Document Type : Original Article

Authors

Armin Abedian Amiri

Ghobad Azari Takami

Mohammad Afsharnasab

Vadood Razavilar

Department of Aquatic Animal Health and Diseases, Faculty of Specialized Veterinary Sciences, Science and Research branch, Islamic Azad University, Tehran, Iran.

Abstract

This study examined the effects during 56 days of feeding of three dietary probiotics on growth performance and feed utilization, intestinal colonization and related health criteria in Oncorhynchus mykiss (rainbow trout). This study included 3 groups: a control group of fish, and fish fed with a basal commercial diet supplemented with 2.5 × 10⁸ CFU g^–1 Enterococcus faecium strain IR5 (group 1) (was micro-encapsulated with sodium alginate) and 1 × 10⁹ CFU g^–1 Enterococcus faecium strain IR5 (group 2) (was micro-encapsulated with sodium alginate)singularly in triplicate. 270 rainbow trout with an average weight of 35.6 ± 3.8 g (mean±SD) were obtained. Fish were acclimatized for 20 days. The probiotics groups showed improvement with respect to weight gain (WG), body weight index fish (BWI) (%), total length (TL), specific growth rate (SGR), feed conversion ratio (FCR), protein efficiency ratio (PER), lactic acid bacteria (LAB) (%) in intestinal, intestinal colonization (log CFU g–¹) and survival (%). At 28 days, group 2 showed improvement with respect to growth performance and feed utilization, intestinal colonization and related health criteria were higher than other groups. At 56 days, the WG and PER in the group 1 were significantly higher than in 2 and control groups (P<0.05). The LAB (%) in intestinal was higher in group 2 than in 1 and it was higher in group 1 than in the control groups after 8 weeks feeding (P<0.05).

Keywords

rainbow trout

Enterococcus faecium

micro-encapsulation

Growth and health performance

feed utilization