Sustainable plant-based diets promote rainbow trout gut microbiota richness and do not alter resistance to bacterial infection

Abstract Background Farmed fish food with reduced fish-derived products are gaining growing interest due to the ecological impact of fish-derived protein utilization and the necessity to increase aquaculture sustainability. Although different terrestrial plant proteins could replace fishmeal proteins, their use is associated with adverse effects. Here, we investigated how diets composed of terrestrial vegetal sources supplemented with proteins originating from insect, yeast or terrestrial animal by-products affect rainbow trout (Onchorynchus mykiss) gut microbiota composition, growth performance and resistance to bacterial infection by the fish pathogen Flavobacterium psychrophilum responsible for frequent outbreaks in aquaculture settings. Results We showed that the tested regimes significantly increased gut bacterial richness compared to full vegetal or commercial-like diets, and that vegetal diet supplemented with insect and yeast proteins improves growth performance compared to full vegetal diet without altering rainbow trout susceptibility to F. psychrophilum infection. Conclusion Our results demonstrate that the use of insect and yeast protein complements to vegetal fish feeds maintain microbiota functions, growth performance and fish health, therefore identifying promising alternative diets to improve aquaculture’s sustainability.

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Choline and Bile Acids Mixture Improved Growth Performance and Intestinal Immunity via Altering Gut Microbiota and Bacterial Metabolites in the Colon of Weaned Piglets.

10.21203/rs.3.rs-32927/v1 ◽

2020 ◽

Author(s):

Yueqin Qiu ◽

Kebiao Li ◽

Shilong Liu ◽

Li Wang ◽

Kaiguo Gao ◽

...

Keyword(s):

Gut Microbiota ◽

Growth Performance ◽

Bile Acids ◽

Control Diet ◽

Choline Chloride ◽

Microbiota Composition ◽

Weaned Piglets ◽

Bacterial Metabolites ◽

G Ratio ◽

Gut Microbiota Composition

Abstract Background: Choline or bile acids has many beneficial roles in physiological function. However, little was known about growth performance, intestinal mucosal function and microbiota-host interactions of weaned piglets in response to choline or bile acids supplementation. This study aimed to investigate the effect of choline and bile acids mixtures (ChB) supplementation on growth performance, intestinal mucosal barrier function, gut microbiota and bacterial metabolites of weaned piglets. One hundred and twenty-eight crossbred (Duroc × Landrace × Large White) weaned piglets (initial body weight: approximately 8 kg; 21 d of age) were randomly allocated to four different dietary treatments(a control diet (Control) and the other three groups were control diet supplemented with 800 mg/kg choline chloride (choline), 500 mg/kg bile acids (bile acids) or 800 mg/kg choline chloride plus 500 mg/kg bile acids (ChB), respectively) and for 28-d feeding trail. Results: ChB significantly increased average daily gain (ADG) and reduced feed/gain (F/G) ratio, associated with elevation of lipase activity and total bile acids level in ileal digesta compared with control diet. Additionally, ChB altered colonic microbiota by increasing the relative abundance of Lactobacillus and Faecalibacterium , and decreasing the relative abundances of unidentified-Clostridiales , Parabacteroides and Unidentified-Ruminococcaceae , when compared with control diet. Meanwhile, ChB increased the butyrate level and decreased the production of bile acid profiles in the colonic digesta. Besides, feeding ChB improved gut immunity, as reflected by increasing the abundance of IL-10 , FXR and mucin2 transcript, while downregulated expression of TLR4 , MyD88 , NF-κBp65 and TNF-α genes in the intestinal mucosa. Quantitative proteomics of jejunal mucosa further showed that ChB regulated the proteins that were related to inflammatory response. Furthermore, the changes in the ADG and genes expression were associated with alteration of gut microbiota composition and their metabolites. Conclusions: Collectively, our findings demonstrated that choline and bile acids mixture may improve the growth performance and intestinal immune response of weaned piglets through alteration of gut microbiota composition and bacterial metabolites, which promoted gut health.

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Streptococcal infections of farmed fish

Journal of the Hellenic Veterinary Medical Society ◽

10.12681/jhvms.15174 ◽

2017 ◽

Vol 55 (2) ◽

pp. 136 ◽

Cited By ~ 2

Author(s):

F. ATHANASSOPOULOU (Φ. ΑΘΑΝΑΣΟΠΟΥΛΟΥ) ◽

R. J. ROBERTS

Keyword(s):

Rainbow Trout ◽

Marine Fish ◽

Bacterial Load ◽

Clinical Signs ◽

Wild Fish ◽

Freshwater Species ◽

Farmed Fish ◽

Fish Food ◽

Important Species ◽

Wide Range

The genus Streptococcus is large and complex, accommodating a wide range of Gram positive bacteria. Only a few biotypes have been isolated from fish and the most pathogenic are those belonging to D serogroup, otherwise known as the Enterococci. Streptococcal septicaemia was first among cultured rainbow trout (Onchorynchus mykiss) in Japan in 1958. Since then, the disease has appeared sporadically or in epizootics among cultured or wild fish both in freshwater and marine environments all over the world. Among the freshwater species infected, rainbow trout (Onchorynchus mykiss) and tilapia (Oreochromis niloticus) are the most important species. Clinical signs vary among species of affected fish. The most common symptoms are loss of appetite, erratic swimming, darkening of body colour, eye lesions, external haemorrhagic lesions and ulcerations. The standard system for identification is based on the antigenicity of the carbohydrate moiety of the cell wall, according to a scheme devised by Lancefìeld in the 1930's. The American freshwater isolates obtained by Robinson & Meyer (1966), Plumb et al. (1974), Rasheed & Plumb (1984) were all typed Lancefield's group Β serotype in contrast to almost all of the much more frequent isolates from marine fish, which are usually untypable Enter ο co ecus-like strains. The Streptococcus strains isolated from yellowtail (Seriola sp), ayu (Plecoglosus altivelis) and flounder (Rhombosolea. sp) have similar biochemical reactions to Streptococcus iniae, a species isolated from dolphins by Pier & Madin (1976), which is defined in Bergey's Manual as a separate species. Kusuda et al.(1991) have analysed numerous strains from yellowtail infections in mariculture and in eels and have concluded, on the basis of DNA/DNA hybridization studies and biochemistry that a specific condition, caused by such streptococci, exists and that these bacteria were closest to Enterococci in characteristics and that infectious coccosis of marine fish, as seen in Japan, should be called "Enterococcal infection". Enterococci released from diseased fish seem to be the main source of infection. It has been shown that these bacteria remain in seawater and particularly in the mud around farms for a long time. Higher numbers of microorganisms exist in the seawater during summer months in contrast to the winter months when the bacterial load is higher in the mud (Kitao et al. 1979). Ghittino & Prearo (1992) have shown that in freshwater fish the outbreak of the disease was related to an organic pollution of the rivers supplying fish farms, associated with high water temperature (21-22°C). Wild fish can also be infected and spread the bacteria. It is generally believed that the infection is horizontal with infection occurring from direct contact with infected fish or contaminated fish food (Robinson & Meyer, 1996). The mechanisms of enterococcal infections pathogenicity are not yet fully understood.

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The Gut Microbiota of Rats under Experimental Osteoarthritis and Administration of Chondroitin Sulfate and Probiotic

Mikrobiolohichnyi Zhurnal ◽

10.15407/microbiolj82.06.064 ◽

2020 ◽

Vol 82 (6) ◽

pp. 64-73

Author(s):

O.H. Korotkyi ◽

◽

T.V. Luhovska ◽

T.M. Serhiychuk ◽

K.O. Dvorshchenko ◽

...

Keyword(s):

Gut Microbiota ◽

Chondroitin Sulfate ◽

Joint Inflammation ◽

Degenerative Joint Disease ◽

Joint Disease ◽

Quantitative Composition ◽

Combined Administration ◽

Osteoarthritis Progression ◽

Experimental Osteoarthritis ◽

Gut Microbiota Composition

Osteoarthritis is a most widespread chronic degenerative joint disease that causes pain, cartilage deformation, and joint inflammation. Adverse alterations of intestinal microbiota like dysbiosis may lead to metabolic syndrome and inflammation, two important components of osteoarthritis progression. Aim. In this study we investigated the effect of chondroitin sulfate and probiotics on the gut microbiome in monoiodoacetate-induced osteoarthritis model in rats. Methods. The species and quantitative composition of feces were determined using diagnostic media with selective properties. Further identification of isolated microorganisms was carried out according to morphological, tinctorial, physiological and metabolic parameters. The results are presented in the form of lg CFU/g. Results. Induction of osteoarthritis caused significant increasing the number of opportunistic enterobacteria and lactose-negative Escherichia coli against the decreasing of lacto- and bifidobacteria that may indicate a dysbiotic condition. Coadministration of chondroitin sulfate and probiotic bacteria has led to improvement the quantitative composition of the gut microbiota in experimental animals, the numerous of Bifidobacterium, Lactobacillus were increasing against decreasing the quantitative composition of opportunistic microorganisms. Conclusions. Monoiodoacetate-induced osteoarthritis caused dysbiosis of gut in rat. We observed beneficial effect of combined administration of chondroitin sulfate and probiotics on gut microbiota composition in rats with experimental osteoarthritis. Thus, adding of supplements like probiotics to standard treatment of osteoarthritis may have potentials to prevent and treat this disease.

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