scholarly journals The Epidermal Microbiome Within An Aggregation of Leopard Sharks (Triakis Semifasciata) Has Taxonomic Flexibility With Gene Functional Stability Across Three Time-Points

2021 ◽  
Author(s):  
Michael Doane ◽  
Colton Johnson ◽  
Shaili Johri ◽  
Emma N. Kerr ◽  
Megan M. Morris ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Functional Characterization ◽  
Time Points ◽  
Leopard Shark ◽  
Average Similarity ◽  
Microbial Groups ◽  
Triakis Semifasciata ◽  
Leopard Sharks ◽  
Biofilm Development ◽  
Host Metabolism

Abstract Background: The epidermis of Chondrichthyan fishes consists of dermal denticles with production of minimal but protein rich mucus that influence the attachment and biofilm development of microbes, facilitating a unique epidermal microbiome. Here, we use metagenomics to provide the taxonomic and functional characterization of the epidermal microbiome of the Triakis semifasciata (leopard shark) across three time-points to identify links between microbial groups and host metabolism. Our aims include 1) describing the variation of microbiome taxa over time and identify those members which are recurrent (present across all time-points, 2) investigating the relationship between the recurrent and flexible taxa (those which are not found consistently across time-points, 3) describing the functional compositions of the microbiome which may suggest links with the host metabolism; and 4) identifying whether the metabolisms are share across microbial genera or found in specific taxa. Results: Microbial members of the microbiome showed high similarity between all individuals (average similarity: 82.74) with relative abundance of those members varying across years, suggesting flexibility of taxa in the microbiome. One hundred and eighty-eight genera were identified as recurrent, including Pseudomonas, Erythrobacter, Alcanivorax, Marinobacter and Sphingopxis being consistently abundance across time-points, while Limnobacter and Xyella exhibited switching patterns with high relative abundance in 2013, Sphingobium and Sphingomona in 2015, and Altermonas, Leeuwenhoekiella, Gramella and Maribacter in 2017. Of the 188 genera identified as recurrent, the top 19 relative abundant genera forming three recurrent groups. The microbiome also displayed high functional similarity between individuals (average similarity: 97.65) with gene function composition being consistent across time-points. Conclusion: These results show that while presence of microbial genera exhibit consistency across time-points, their abundances do fluctuate. Functions however remain stable across time points; thus, we suggest the leopard shark microbiomes exhibit functional redundancy. We hypothesize this may be the result of the host’s epidermal attributes structuring the microbiome. In addition, we show the co-existence of many microbial genera that carry genes which may enable the microbes to use the nutrients provided by the elasmobranch’s metabolism.

scholarly journals The Epidermal Microbiome Within An Aggregation of Leopard Sharks (Triakis Semifasciata) Has Taxonomic Flexibility With Gene Functional Stability Across Three Time-Points

2021 ◽  
Author(s):  
Michael Doane ◽  
Colton Johnson ◽  
Shaili Johri ◽  
Emma N. Kerr ◽  
Megan M. Morris ◽  
...  
Keyword(s):  
Relative Abundance ◽  
Functional Characterization ◽  
Time Points ◽  
Leopard Shark ◽  
Average Similarity ◽  
Microbial Groups ◽  
Triakis Semifasciata ◽  
Leopard Sharks ◽  
Biofilm Development ◽  
Host Metabolism

Abstract Background: The epidermis of Chondrichthyan fishes consists of dermal denticles with production of minimal but protein rich mucus that influence the attachment and biofilm development of microbes, facilitating a unique epidermal microbiome. Here, we use metagenomics to provide the taxonomic and functional characterization of the epidermal microbiome of the Triakis semifasciata (leopard shark) across three time-points to identify links between microbial groups and host metabolism. Our aims include 1) describing the variation of microbiome taxa over time and identify those members which are recurrent (present across all time-points, 2) investigating the relationship between the recurrent and flexible taxa (those which are not found consistently across time-points, 3) describing the functional compositions of the microbiome which may suggest links with the host metabolism; and 4) identifying whether the metabolisms are share across microbial genera or found in specific taxa. Results: Microbial members of the microbiome showed high similarity between all individuals (average similarity: 82.74) with relative abundance of those members varying across years, suggesting flexibility of taxa in the microbiome. One hundred and eighty-eight genera were identified as recurrent, including Pseudomonas, Erythrobacter, Alcanivorax, Marinobacter and Sphingopxis being consistently abundance across time-points, while Limnobacter and Xyella exhibited switching patterns with high relative abundance in 2013, Sphingobium and Sphingomona in 2015, and Altermonas, Leeuwenhoekiella, Gramella and Maribacter in 2017. Of the 188 genera identified as recurrent, the top 19 relative abundant genera forming three recurrent groups. The microbiome also displayed high functional similarity between individuals (average similarity: 97.65) with gene function composition being consistent across time-points. Conclusion: These results show that while presence of microbial genera exhibit consistency across time-points, their abundances do fluctuate. Functions however remain stable across time points; thus, we suggest the leopard shark microbiomes exhibit functional redundancy. We hypothesize this may be the result of the host’s epidermal attributes structuring the microbiome. In addition, we show the co-existence of many microbial genera that carry genes which may enable the microbes to use the nutrients provided by the elasmobranch’s metabolism.

Demography of the central california population of the Leopard Shark (Triakis semifasciata)

1992 ◽  
Vol 43 (1) ◽  
pp. 183 ◽  
Author(s):  
GM Cailliet
Keyword(s):  
Population Growth ◽  
Reproductive Rate ◽  
Shark Species ◽  
Sandbar Shark ◽  
Lemon Shark ◽  
Carcharhinus Plumbeus ◽  
Net Reproductive Rate ◽  
Leopard Shark ◽  
Triakis Semifasciata ◽  
Leopard Sharks

Demographic analyses can be quite useful for effectively managing elasmobranch fisheries. However, they require valid estimates of age-specific mortality and natality rates, in addition to information on the distribution, abundance, habits and reproduction of the population, to produce reliable estimates of population growth. Because such detailed ecological information is usually unavailable, complete demographic analyses have been completed for only four shark species: the spiny dogfish, Squalus acanthias; the soupfin shark, Galeorhinus australis; the lemon shark, Negaprion brevirostris; and most recently the sandbar shark, Carcharhinus plumbeus. In California, reliable estimates of age, growth, mortality, age at maturity, and fecundity are available only for the leopard shark, Triakis semifasciata. A demographic analysis of this species yielded a net reproductive rate (Ro) of 4.467, a generation time (G) of 22.35 years, and an estimate of the instantaneous population growth coefficient (r) of 0.067. If the mean fishing pressure over 10 years (F= 0.084) is included in the survivorship function, Ro and r are reduced considerably, especially if leopard sharks first enter the fishery at early ages. A size limit of 120 cm TL (estimated age 13 years), especially for female sharks, is tentatively proposed for the leopard shark fishery.

scholarly journals Heterocercal tail function in leopard sharks: a three-dimensional kinematic analysis of two models

1996 ◽  
Vol 199 (10) ◽  
pp. 2253-2268 ◽  
Author(s):  
L Ferry ◽  
G Lauder
Keyword(s):  
High Speed ◽  
Classical Model ◽  
Three Dimensional ◽  
Strong Support ◽  
Three Dimensions ◽  
Video Cameras ◽  
Leopard Shark ◽  
Triakis Semifasciata ◽  
Leopard Sharks ◽  
Tail Function

Two different models have been proposed to explain the function of the heterocercal tail in shark locomotion. The classical model proposes that, as a result of lift generated by the tail as it beats, the net force acting on the tail is directed dorsally and anteriorly. In contrast, Thomson's model suggests that the tail generates a net force directed through the shark's center of gravity, i.e. ventrally and anteriorly. In this study, we evaluate these two models by describing the three-dimensional kinematics of the heterocercal tail in the leopard shark Triakis semifasciata during swimming. Lateral and posterior views of the tail were examined from four individuals swimming in a flow tank at 1.2 L s-1 (where L is total length) using two high-speed video cameras filming simultaneously at 250 fields s-1. These two simultaneous views allowed eight landmarks on the tail to be followed in three dimensions through time. These landmarks allowed the tail to be divided into separate surfaces whose orientation over time was calculated. Points located anteriorly on the tail go through significantly smaller excursions and reach their maximum lateral excursion significantly earlier in the beat cycle than points on the trailing edge of the tail. Three-dimensional angle calculations show that the terminal lobe leads the ventral lobe through a beat, as predicted by the classical model. Dye-stream visualizations confirmed that this pattern of movement deflects water ventrally and posteriorly to the moving tail, providing strong support for the classical model. Additionally, our results show that a three-dimensional analysis is critical to understanding the function of the heterocercal tail.

Effects of prey size and mobility on prey-capture kinematics in leopard sharks triakis semifasciata

1998 ◽  
Vol 201 (16) ◽  
pp. 2433-2444 ◽  
Author(s):  
LA Ferry-Graham
Keyword(s):  
Prey Item ◽  
High Speed ◽  
Prey Capture ◽  
Live Prey ◽  
Leopard Shark ◽  
Suction Index ◽  
Item Size ◽  
Triakis Semifasciata ◽  
Leopard Sharks ◽  
Prey Items

Recent work on teleosts suggests that attack behaviors or kinematics may be modified by a predator on the basis of the size of the prey or the ability of the prey to sense predators and escape capture (elusivity). Sharks are generally presumed to be highly visual predators; thus, it is reasonable to expect that they might also be capable of such behavioral modulation. In this study, I investigated the effect of prey item size and type on prey-capture behavior in leopard sharks (Triakis semifasciata) that had been acclimated to feeding in the laboratory. Using high-speed video, sharks were filmed feeding on two sizes of the same prey item (thawed shrimp pieces) and two potentially more elusive prey items (live earthworms and live mud shrimp). In leopard sharks, little effect of prey elusivity was found for kinematic variables during prey capture. However, the large proportion of successful captures of the live prey suggests that they did not prove to be truly elusive prey items for the leopard shark. There were significant size effects on prey-capture kinematics, with the larger non-elusive items inducing greater head expansion during prey capture. Ram-suction index values also indicated that strikes on large, non-elusive prey had a significantly larger suction component than strikes on similar small prey items. This finding is interesting given that the two sizes of non-elusive prey item offered no differential challenge in terms of a performance consequence (reduced capture success).

scholarly journals Interaction of Salmonella with E. coli and Proteus spp. in Biofilm Formation

2021 ◽  
pp. 30-45
Author(s):  
S. U. Pathiranage ◽  
D. N. N. Madushanka ◽  
K. V. D. M. Hasintha ◽  
H. C. Nadishani ◽  
G. C. P. Fernando ◽  
...  
Keyword(s):  
Biofilm Formation ◽  
Broiler Chicken ◽  
Chicken Meat ◽  
Salmonella Spp ◽  
E Coli ◽  
Time Points ◽  
Dual Cultures ◽  
Microtitre Plate Assay ◽  
Biofilm Development ◽  
Numerous Time

Aims: Investigate the interaction of Salmonella spp. with E. coli and Proteus spp. in biofilm formation as mono and dual-species at different time durations Experimental Design: Salmonella, Proteus, and E. coli were isolated from Broiler chicken meat, and the biofilm-forming ability of these organisms were studied. Place and Duration of Study: The study was conducted at the Laboratory of Livestock Production, Faculty of Agricultural Sciences, Sabaragamuwa University of Sri Lanka, from 2019 December to 2020 May. Methodology: This study investigated the biofilm-forming ability of Salmonella as a mono species and its interaction with E. coli and Proteus in the process of biofilm formation. Microorganisms used for this study were isolated from broiler chicken meat. Biofilm was quantified using a microtitre plate assay. The interaction effects were tested at the temperature of 280C in different time durations (up to 120 hours). Results: Salmonella 1 and Proteus monocultures showed significantly higher biofilm-forming ability than Salmonella 3 isolate at all tested time points. At 120 hr, additionally to the salmonella 1 and Proteus isolates E. coli also formed significantly higher biofilms than Salmonella 3. However, Salmonella 3 was the lowest biofilm former as mono biofilm at all tested time durations. Salmonella 1 interaction with Salmonella 3 isolates formed less biofilms than Salmonella 1 mono biofilm at 48hr and 72hr correspondingly. Salmonella 1 and its interactions with Salmonella 3, Proteus, E. coli showed similar biofilm-forming abilities without significant differences at all other tested time points. Specifically, Salmonella 3 interaction with Salmonella 1 as dual biofilm showed higher biofilm-forming ability than Salmonella 3 mono biofilm at all tested time points. Tested isolates and their interaction achieved the highest biofilm formation at numerous time points. In fact, at 48hr, Salmonella 3 isolates and its interaction of Proteus, E. coli, and Salmonella 1 interaction with Proteus attained their highest biofilm formation abilities. The highest biofilm formation was achieved by Salmonella 1 isolate as mono biofilm and Salmonella 1 interaction with E. coli as dual biofilm at 72hr. Biofilm-forming trend of respective isolates and interactions showed numerous patterns at tested time durations. Specifically, E. coli rapidly enhanced its biofilm-forming ability as monoculture from 24 hr to 120 hr. Proteus, Salmonella 3 as monocultures, Salmonella 3 interaction with Proteus and E. coli as dual cultures showed progressive biofilm development from 24 hr to 48 hr. Salmonella 1 monoculture and its interaction with Salmonella 3, E. coli as dual biofilm improved their biofilm-forming ability from 24 hr to 72 hr. Similar to Salmonella 3 interaction with Proteus, Salmonella 1 interaction with Proteus also increased its biofilm-forming ability from 24 hr to 48 hr. Conclusions: This study concluded that there is a variation among isolates and their combinations in forming the biofilms, where there is an enhancement of biofilm in dual-species over the mono-species in some interaction, and there is a reduction in biofilm formation by dual-species with some combinations. Further, this concluded that Salmonella is interacting with other commonly found bacteria such as Proteus and E. coli in biofilm formation.

Tissue-specific isotope trophic discrimination factors and turnover rates in a marine elasmobranch: empirical and modeling results

2012 ◽  
Vol 69 (3) ◽  
pp. 551-564 ◽  
Author(s):  
Luis Malpica-Cruz ◽  
Sharon Z. Herzka ◽  
Oscar Sosa-Nishizaki ◽  
Juan Pablo Lazo
Keyword(s):  
Natural Populations ◽  
Nitrogen Isotope ◽  
Cartilage Tissue ◽  
Turnover Rates ◽  
Isotopic Equilibrium ◽  
Isotope Turnover ◽  
Discrimination Factors ◽  
Triakis Semifasciata ◽  
Leopard Sharks ◽  
Trophic Discrimination

There are very few studies reporting isotopic trophic discrimination factors and turnover rates for marine elasmobranchs. A controlled laboratory experiment was conducted to estimate carbon and nitrogen isotope trophic discrimination factors and isotope turnover rates for blood, liver, muscle, cartilage tissue, and fin samples of neonate to young-of-the-year leopard sharks ( Triakis semifasciata ). Trophic discrimination factors varied (0.13‰–1.98‰ for δ13C and 1.08‰–1.76‰ for δ15N). Tissues reached or were close to isotopic equilibrium to the new diet after about a threefold biomass gain and 192 days. Liver and blood exhibited faster isotope turnover than muscle, cartilage tissue, and fin samples, and carbon isotopes turned over faster than those of nitrogen. Metabolic turnover contributed substantially to isotopic turnover, which differs from most reports for young marine teleosts. We modeled the relationship between muscle turnover rates and shark size by coupling laboratory results with growth rate estimates for natural populations. Model predictions for small, medium, and large wild leopard sharks indicate the time to isotopic equilibrium is from one to several years.

scholarly journals Modulation of the gut microbiome: a systematic review of the effect of bariatric surgery

2018 ◽  
Vol 178 (1) ◽  
pp. 43-56 ◽  
Author(s):  
Yan Guo ◽  
Zhi-Ping Huang ◽  
Chao-Qian Liu ◽  
Lin Qi ◽  
Yuan Sheng ◽  
...  
Keyword(s):  
Systematic Review ◽  
Bariatric Surgery ◽  
Gut Microbiota ◽  
Strong Evidence ◽  
Gut Microbiome ◽  
Animal Experiments ◽  
Human Metabolism ◽  
Microbial Groups ◽  
Host Metabolism

Objective Bariatric surgery is recommended for patients with obesity and type 2 diabetes. Recent evidence suggested a strong connection between gut microbiota and bariatric surgery. Design Systematic review. Methods The PubMed and OVID EMBASE were used, and articles concerning bariatric surgery and gut microbiota were screened. The main outcome measures were alterations of gut microbiota after bariatric surgery and correlations between gut microbiota and host metabolism. We applied the system of evidence level to evaluate the alteration of microbiota. Modulation of short-chain fatty acid and gut genetic content was also investigated. Results Totally 12 animal experiments and 9 clinical studies were included. Based on strong evidence, 4 phyla (Bacteroidetes, Fusobacteria, Verrucomicrobia and Proteobacteria) increased after surgery; within the phylum Firmicutes, Lactobacillales and Enterococcus increased; and within the phylum Proteobacteria, Gammaproteobacteria, Enterobacteriales Enterobacteriaceae and several genera and species increased. Decreased microbial groups were Firmicutes, Clostridiales, Clostridiaceae, Blautia and Dorea. However, the change in microbial diversity is still under debate. Faecalibacterium prausnitzii, Lactobacillus and Coprococcus comes are implicated in many of the outcomes, including body composition and glucose homeostasis. Conclusions There is strong evidence to support a considerable alteration of the gut microbiome after bariatric surgery. Deeper investigations are required to confirm the mechanisms that link the gut microbiome and metabolic alterations in human metabolism.

Sign in / Sign up

Export Citation Format

Share Document