Protective Effects of Non-Encapsulated and Microencapsulated Lactobacillus Delbrueckii Subsp. Bulgaricus in Rainbow Trout (Oncorhynchus Mykiss) Exposed to Lead (Pb) Via Diet

Abstract

The present study was designed to investigate the effects of dietary non-encapsulated and microencapsulated Lactobacillus delbrueckii subsp. bulgaricus on growth performance, intestinal enzymatic activities, antioxidant capacity and hepato-biochemical parameters of rainbow trout before or after exposure to lead via diet. Fingerling fish (16 ± 4 g) were divided into four groups: negative control (NC), positive control (PC), probiotic (PR) and encapsulated probiotic (EN-PR). During the pre-exposure period (days 0-45), fish in the NC and PC groups received the basal diet, whereas fish in the PR and EN-PR groups were fed with basal diet containing 108 CFU g−1 feed of non-encapsulated and microencapsulated probiotic, respectively. During the exposure period (days 46-66), the fish in the probiotic and PC groups were co-treated with 500 μg g−1 feed of lead nitrate. Blood, liver and gut samples were taken at days 0, 45, 52, 59 and 66. The results revealed that growth performance and intestinal enzymatic activities were significantly (p< 0.05) improved in the probiotic groups compared to the NC group (day 45). Dietary exposure to lead resulted in the highest levels of liver aspartate aminotransferase (AST), liver alkaline phosphatase (ALP) and serum malondialdehyde (MDA), and the lowest activities of serum superoxide dismutase (SOD) and catalase (CAT) in the PC group (day 66). The levels of liver ALP were significantly (p< 0.05) lower in the probiotic groups compared to the NC and PC groups prior to and after exposure to dietary lead. Serum levels of total protein, albumin, SOD, CAT and glutathione (GSH) were significantly increased in fish fed with both non-encapsulated and microencapsulated probiotics (p< 0.05). However, microencapsulated probiotic showed the greatest potential for alleviation of the disturbed activities of intestinal and hepatic enzymes, and improvement of serum biochemical and antioxidant parameters. Our findings suggest that L. delbrueckii subsp. bulgaricus, particularly in the microencapsulated form, can be used as a potential probiotic to protect rainbow trout from dietborne lead toxicity.

Single and Multi-Strain Probiotics Supplementation in Commercially Prominent Finfish Aquaculture: Review of the Current Knowledge

“…Dietary supplementation with LABs L. buchneri , L. fermentum , and the yeast S. cerevisiae together for 130 days improved innate immunity and immune genes transcription without alteration of heamato-biochemical parameters [ 91 ]. Modulation of these parameters was also observed after feeding with various strains of LAB [ 92 , 93 ]. Administration with L. plantarum , Lac.…”

Interactive effects of dietary betaine and chromium picolinate on the immunomodulation, antioxidative response and disease resistance of Nile tilapia ( Oreochromis niloticus )

“…Several multi‐sourced additives are implicated in improving fish production for the benefit of the aquaculture industry. Dietary plant proteins, lipids, prebiotics, and probiotics have been investigated to replace the more expensive fish meal wholly or partially (Mohammadian, Ghanei‐Motlagh, Jalali, et al, 2021; Mohammadian, Ghanei‐Motlagh, Molayemraftar, et al, 2021; Zahran et al, 2014). However, feed additives that improve feed, enhance the immune status, regulate antioxidant parameters and increase disease resistance are notably more critical (Ahmed et al, 2021; Alemayehu et al, 2018; Al‐Wakeel et al, 2019; Bai et al, 2015; Zahran et al, 2020).…”