The presence, nature, and role of gut microflora in aquatic invertebrates: A synthesis

1993 ◽  
Vol 25 (3) ◽  
Author(s):  
JeanM. Harris

2018 ◽  
Vol 09 (01) ◽  
pp. 132-136 ◽  
Author(s):  
Harshini Manohar ◽  
Madhavapuri Pravallika ◽  
Preeti Kandasamy ◽  
Venkatesh Chandrasekaran ◽  
Ravi Philip Rajkumar

ABSTRACTBackground: Gut microflora influences neural development through complex mechanisms. Feeding practices, especially breastfeeding influence gut microbiome and thereby play a pivotal role in immune and neural development. Current understandings of the role of healthy distal gut microflora in the development of immune and neural systems provide insights into immunological mechanisms as one of the possible etiologies in autism spectrum disorder (ASD). Studies have shown that optimal breastfeeding is associated with lower odds of being at-risk for ASD and children with ASD are suboptimally breastfed. Methods: The feeding practices of children with ASD (n = 30) was compared to their typically developing siblings as matched controls (n = 30). Information regarding feeding practices was collected from mothers through a semi-structured questionnaire. Results: About 43.3% of children with ASD received exclusive breastfeeding, whereas 76.7% of their typically developing siblings were exclusively breastfed. Exclusive breastfeeding was associated with lower odds for ASD (odds ratio [OR] = 0.166; 95% confidence interval [CI] = 0.025–0.65), while early introduction of top feeds was associated with higher odds (OR = 6; 95% CI = 1.33–55.19). Difficulties in breastfeeding were attributed to child-related factors in 13.2% of the children. Conclusion: Children with ASD are suboptimally breastfed compared to their typically developing siblings. Exclusive breastfeeding may confer protection in vulnerable children. Further studies on larger prospective sample are required to establish the association.



2015 ◽  
Vol 35 (suppl_1) ◽  
Author(s):  
Daiko Wakita ◽  
Yosuke Kurashima ◽  
Yoshihiro Takasato ◽  
Youngho Lee ◽  
Kenichi Shimada ◽  
...  

Background: KD is the leading cause of acquired heart disease in the US. We have demonstrated the critical role of innate immune responses via IL-1R/MyD88 signaling in the Lactobacillus casei cell wall extract (LCWE)-induced KD mouse model. The diversity and composition of microflora (both bacterial and fungal) have been associated with the regulation and alterations of immune responses and various pathologies. However, the role of gut microbiota in immunopathology of KD has not been investigated. Objective: To evaluate the role of gut microflora in development of coronary arteritis, and vascular abnormalities in KD mouse model. Methods and Results: We investigated the role of gut microflora in the LCWE-induced KD mouse model, using Specific-Pathogen Free (SPF) and Germ Free (GF) mice (C57BL/6). GF mice showed a significant decrease of KD lesions, including coronary arteritis compared with SPF mice. The development of LCWE-induced AAA, which we recently discovered in this mouse model, was also markedly diminished in GF mice. In addition to GF mice, we also investigated the specific role of commensal bacteria and/or fungi, and determined whether altered microorganism burden in this KD mouse model contributes to disease severity. To deplete bacteria and/or fungi in the gut microflora, we exposed pregnant SPF mice and their offspring to antibiotics cocktail (Abx) or antifungal drug (fluconazole; Fluc) in their drinking water for 5 wks and induced KD. The mice treated with Abx or Fluc had significantly reduced coronary arteritis and AAA compared to controls. The Abx plus Fluc administration showed marked decrease of KD vasculitis. Conclusions: We demonstrate here that gut microflora play a critical role in the development of KD vasculitis in LCWE-induced mouse model. Our results suggest that both bacteria and fungi in the intestinal microbiota may control the induction and severity of KD vasculitis. These findings provide a new perspective on the potential role of the microbiome in KD pathogenesis and may offer new diagnostic and therapeutic strategies for KD patients.



2019 ◽  
Vol 70 (4) ◽  
pp. 554
Author(s):  
Shaojun Chen ◽  
Dong Wang

Aquatic invertebrates play an important role in plant decomposition. However, little information is available regarding the relative importance of micro-, meio- and macroinvertebrates in this process, particularly their role in the decomposition of buried organic matter. To investigate the role of these invertebrates in the decomposition of the aquatic macrophyte Vallisneria natans, leaves of V. natans were placed in litterbags with four different mesh sizes (0.025, 0.042, 0.5 and 5mm) and the bags were either incubated at the sediment–water (SW) interface or buried at a depth of 10cm (B10) for 60 days in Lake Nanhu, China, in July 2015. Increased mesh size significantly increased the loss of plant mass. The decomposition rate ranged from 0.0173 to 0.0467day–1 in the SW treatment, and from 0.0083 to 0.0280day–1 in the B10 treatment. Excluding microinvertebrates, burial significantly affected microbial respiration and invertebrate abundance. Increased mesh size increased invertebrate abundance and richness, but did not significantly affect microbial respiration in either treatment. The average contribution of micro-, meio- and macroinvertebrates and microbes to plant mass loss in the SW treatment was 23.1, 13.5, 7.0 and 56.5% respectively, compared with 19.7, 24.5, 12.3 and 43.5% respectively in the B10 treatment. The results of this study reveal the important but underestimated role of micro- and meioinvertebrates in macrophyte decomposition.



Author(s):  
P. J. Hayward ◽  
Paul H. Harvey

The spatial settlement of marine invertebrate larvae is not a random process. The distribution of the adults of a particular species is influenced by the behavioural responses of the animal to a range of environmental stimuli which, in the case of many sessile invertebrates, result in the display of clear substrate selection. The role of habitat selection in determining the distribution of aquatic invertebrates has been the subject of a review by Meadows & Campbell (1972). The selection of algal substrata by the larvae of various intertidal species of Bryozoa has been demonstrated by Ryland (1959); among these, the ctenostomatous bryozoans Alcyonidium hirsutum and A. polyoum were shown to exhibit a strong preference for fronds of the alga Fucus serratus, an experi-mental result which accorded well with the distribution of the two species on the shore (Ryland, 1962).



1993 ◽  
Vol 44 (3) ◽  
pp. 405 ◽  
Author(s):  
G Annison

It has been well established over a number of years that the apparent metabolisable energy (AME) value of wheat is highly variable. In 1983 and 1987 in Australia two surveys indicated that approximately 25% of wheats have AME values lower than 13 MJ/kg.DM (range 10.4-15.9 MJ/kg.DM). Following recent studies it has been proposed that the soluble non-starch polysaccharide cell-wall components of wheat (mainly arabinoxylan with some G-glucan) have an anti-nitritive activity when wheats are present at high levels in broiler diets and are responsible for the low-AME wheat phenomenon. The main findings supporting this hypothesis are (1) wheat AME values are negatively correlated with soluble non-starch polysaccharide levels, (2) low level addition (30g/kg) of commercially available pur non-starch polysaccharides to broiler diets depresses the AME,of the diets, (3) degradation of the cell wall polysaccharides in situ by addition of glycanases to broiler diets raises AME values, and (4) addition of purified wheat arabinoxylan to broiler diets depresses the AME in a dose-dependant manner. The AME depression is a result of the inhibition of starch, lipid and proteindigestion in the fore-gut. This paper reviews the experiments and the data from the studies and discusses further aspects of the anti-nutritive activity of cereal polysaccharides in broiler diets. The possible role of the gut microflora in the growth depression observed when diets containing high levels of rye, barley and wheat are fed to broiler chickens is also examined.



Author(s):  
A.C. Longland ◽  
W.H. Close ◽  
A.G. Low

The utilization of diets high in fibre (defined here as non-starch polysaccharide - NSP) is dependent on the extent to which the NSP is fermented by the gut microflora, and the subsequent utilization by the animal of the end-products of fermentation - the VFAs. It has frequently been assumed that fermentation of NSP in the pig occurs almost exclusively in the hind-gut. However, a number of studies using pigs fitted with ileal-cannulas have suggested that some fermentation of NSP may occur prior to the hind-gut (e.g. Graham et al., 1985). The aim of this study was to determine the relative roles of the small and large intestine in a) the digestion of feeds containing non-starch polysaccharides, and b) the subsequent utilization of energy by growing pigs. This was achieved by comparing the abilities of intact or ileo-rectomised pigs to digest and grow on cereal-based diets containing 0 or 300 g/kg sugar beet pulp.



2004 ◽  
Vol 82 (6) ◽  
pp. 835-840 ◽  
Author(s):  
Jordi Figuerola ◽  
Andy J Green ◽  
Katrina Black ◽  
Beth Okamura

Waterbirds have been proposed as important vectors for the passive dispersal of those aquatic invertebrates and plants that lack a capacity for active dispersal between isolated water bodies. We analysed the frequency of internal transport of bryozoan propagules (statoblasts) by waterbirds in Doñana, Spain, by examining their presence in the intestines and ceca of dead birds and analysing the role of different aspects of gut characteristics in explaining variation in the presence/absence and abundance of statoblasts. Of the 228 samples examined, 7.9% presented intact statoblasts of Plumatella fungosa (Pallas, 1768), Plumatella emarginata Allman, 1844, and two unidentified Plumatella species. For a given bird species, individuals with heavier gizzards and shorter ceca had a lower incidence and abundance of statoblasts in the lower gut. Grit mass and intestine length were unrelated to the presence or abundance of statoblasts. Our results suggest that waterbirds frequently transport bryozoans on a local scale, with lighter gizzards and longer ceca favouring such transport. Lighter gizzards are likely to destroy fewer propagules before they reach the lower gut. Species and individuals with longer ceca are particularly good candidates for long-distance dispersal of bryozoans, given the longer passage time of propagules that enter the ceca.



Circulation ◽  
2015 ◽  
Vol 131 (suppl_2) ◽  
Author(s):  
Daiko Wakita ◽  
Yosuke Kurashima ◽  
Yoshihiro Takasato ◽  
Youngho Lee ◽  
Kenichi Shimada ◽  
...  

Background: Kawasaki Disease (KD) is the leading cause of acquired heart disease in the US. We have demonstrated the critical role of innate immune responses via IL-1R/MyD88 signaling in the Lactobacillus casei cell wall extract (LCWE)-induced KD mouse model. The diversity and composition of microflora (both bacterial and fungal) have been associated with the regulation and alterations of immune responses and various pathologies. However, the role of gut microbiota in immunopathology of KD has not been investigated. Objective: To evaluate the role of gut microflora in development of coronary arteritis, and vascular abnormalities in KD mouse model. Methods and Results: We investigated the role of gut microflora in the LCWE-induced KD mouse model, using Specific-Pathogen Free (SPF) and Germ Free (GF) mice (C57BL/6). GF mice showed a significant decrease of KD lesions, including coronary arteritis compared with SPF mice. The development of LCWE-induced AAA, which we recently discovered in this mouse model, was also markedly diminished in GF mice. In addition to GF mice, we also investigated the specific role of commensal fungi, and determined whether altered fungal burden in this KD mouse model contributes to disease severity. To deplete fungi in the gut microflora, we exposed pregnant SPF mice and their offspring to fluconazole (antifungal) in their drinking water for 5 wks and induced KD. The fluconazole treated mice had significantly reduced coronary arteritis, and AAA compared to controls. Since Dectin-1 has emerged as a key receptor that recognizes β-1,3-glucans found in the cell wall of nearly all fungi, we next induced KD in Dectin-1 deficient mice. Dectin-1 deficient mice also had significantly reduced KD lesions such as coronary arteritis compared with WT mice. Conclusions: We demonstrate here that gut microflora play a critical role in the development of KD vasculitis in LCWE-induced mouse model. Our results suggest that fungi in the intestinal microbiota may specifically control the induction and severity of KD vasculitis, which may be mediated by Dectin-1. These findings provide a new perspective on the potential role of the microbiome in KD pathogenesis and may offer new diagnostic and therapeutic strategies for KD patients.



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