scholarly journals Antagonistic interplay between pH and food resources affects copepod traits and performance in a year-round upwelling system

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Victor M. Aguilera ◽  
Cristian A. Vargas ◽  
Hans G. Dam
Keyword(s):  
Ocean Acidification ◽  
Egg Production ◽  
Egg Size ◽  
Ingestion Rate ◽  
Food Resources ◽  
Low Ph ◽  
Phenotypic Traits ◽  
Upwelling System ◽  
And Performance ◽  
The Impact

AbstractLinking pH/pCO2 natural variation to phenotypic traits and performance of foundational species provides essential information for assessing and predicting the impact of ocean acidification (OA) on marine ecosystems. Yet, evidence of such linkage for copepods, the most abundant metazoans in the oceans, remains scarce, particularly for naturally corrosive Eastern Boundary Upwelling systems (EBUs). This study assessed the relationship between pH levels and traits (body and egg size) and performance (ingestion rate (IR) and egg reproduction rate (EPR)) of the numerically dominant neritic copepod Acartia tonsa, in a year-round upwelling system of the northern (23° S) Humboldt EBUs. The study revealed decreases in chlorophyll (Chl) ingestion rate, egg production rate and egg size with decreasing pH as well as egg production efficiency, but the opposite for copepod body size. Further, ingestion rate increased hyperbolically with Chl, and saturated at ~1 µg Chl. L−1. Food resources categorized as high (H, >1 µg L−1) and low (L, <1 µg L−1) levels, and pH-values categorized as equivalent to present day (≤400 µatm pCO2, pH > 7.89) and future (>400 µatm pCO2, pH < 7.89) were used to compare our observations to values globally employed to experimentally test copepod sensitivity to OA. A comparison (PERMANOVA) test with Chl/pH (2*2) design showed that partially overlapping OA levels expected for the year 2100 in other ocean regions, low-pH conditions in this system negatively impacted traits and performance associated with copepod fitness. However, interacting antagonistically with pH, food resource (Chl) maintained copepod production in spite of low pH levels. Thus, the deleterious effects of ocean acidification are modulated by resource availability in this system.

scholarly journals Variation in brachiopod microstructure and isotope geochemistry under low pH–ocean acidification–conditions

2018 ◽  
Author(s):  
Facheng Ye ◽  
Hana Jurikova ◽  
Lucia Angiolini ◽  
Uwe Brand ◽  
Gaia Crippa ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Ocean Acidification ◽  
Isotope Geochemistry ◽  
Shell Growth ◽  
Low Ph ◽  
Secondary Layer ◽  
Ph Conditions ◽  
One Year ◽  
The Impact ◽  
Δ13c And Δ18o

Abstract. Throughout the last few decades and in the near future CO2–induced ocean acidification is potentially a big threat to marine calcite-shelled animals (e.g., brachiopods, bivalves, corals and gastropods). Despite the great number of studies focusing on the effects of acidification on shell growth, metabolism, shell dissolution and shell repair, the consequences on biomineral formation remain poorly understood, and only few studies addressed contemporarily the impact of acidification on shell microstructure and geochemistry. In this study, a detailed microstructure and stable isotope geochemistry investigation was performed on nine adult brachiopod specimens of Magellania venosa (Dixon, 1789), grown in the natural environment as well as in controlled culturing experiments at different pH conditions (ranging 7.35 to 8.15 ± 0.05) over different time intervals (214 to 335 days). Details of shell microstructural features, such as thickness of the primary layer, density and size of endopunctae and morphology of the basic structural unit of the secondary layer were analysed using scanning electron microscopy (SEM). Stable isotope compositions (δ13C and δ18O) were tested from the secondary shell layer along shell ontogenetic increments in both dorsal and ventral valves. Based on our comprehensive dataset, we observed that, under low pH conditions, M. venosa produced a more organic-rich shell with higher density of and larger endopunctae, and smaller secondary layer fibres, when subjected to about one year of culturing. Also, increasingly negative δ13C and δ18O values are recorded by the shell produced during culturing and are related to the CO2–source in the culture setup. Both the microstructural changes and the stable isotope results are similar to observations on brachiopods from the fossil record and strongly support the value of brachiopods as robust archives of proxies for studying ocean acidification events in the geologic past.

scholarly journals Effects of low pH and raised temperature on egg production, hatching and metabolic rates of a Mediterranean copepod species (Acartia clausi) under oligotrophic conditions

2013 ◽  
Vol 15 (1) ◽  
pp. 74 ◽  
Author(s):  
S. ZERVOUDAKI ◽  
C. FRANGOULIS ◽  
L. GIANNOUDI ◽  
E. KRASAKOPOULOU
Keyword(s):  
Ocean Acidification ◽  
Egg Production ◽  
Multiple Stressors ◽  
Low Ph ◽  
Combined Effect ◽  
Vital Rates ◽  
Coastal Station ◽  
Acartia Clausi ◽  
Negative Effect ◽  
Egg Production Rate

This study includes the first information on the combined effect of low pH and raised temperature on egg production rate (EP), hatching success (HS), excretion and respiration of the Mediterranean copepod Acartia clausi. Adult individuals of A. clausi and fresh surface seawater were collected at a coastal station in Saronikos Gulf during April 2012. Four different conditions were applied: two different pH levels (present: 8.09 and future: 7.83) at two temperature values (present: 16°C and present+4 °C= 20°C). EP and HS success decreased significantly over the duration of exposure at future pH at both temperature conditions. However, the analysis of the combined effect of pH, T, chlorophyll α and the duration of the experiments on EP and HS revealed that ocean acidification had no discernible effect, whereas warming; food and the duration of exposure were more significant for the reproductive output of A. clausi. Temperature appeared to have a positive effect on respiration and excretion. Acidification had no clear effect on respiration, but a negative effect on the A. clausi excretion was observed. Acidification and warming resulted in the increase of the excretion rate and the increase was higher than that observed by warming only. Our findings showed that a direct effect of ocean acidification on copepod’s vital rates was not obvious, except maybe in the case of excretion. Therefore, the combination of acidification with the ambient oligotrophic conditions and the warming could result in species being less able to allocate resources for coping with multiple stressors.

scholarly journals Food Resources Biodiversity: The Case of Local Cattle in Slovakia

2021 ◽  
Vol 13 (3) ◽  
pp. 1296
Author(s):  
Radovan Kasarda ◽  
Luboš Vostrý ◽  
Hana Vostrá-Vydrová ◽  
Kristína Candráková ◽  
Nina Moravčíková
Keyword(s):  
Food Resources ◽  
Significant Loss ◽  
Phenotypic Traits ◽  
Production Traits ◽  
Effective Population ◽  
Production Type ◽  
Genome Wide Data ◽  
Differentiation Degree ◽  
Genomic Inbreeding ◽  
The Impact

This study aimed to assess the level of biodiversity in selected local cattle populations as important food resources in Slovakia. The biodiversity level was derived from the genome-wide data collected for dairy (Jersey), dual-purpose (Slovak Pinzgau, Slovak Spotted), and beef breeds (Charolais, Limousine). The commonly used indices, genomic inbreeding (FROH, FGRM, FHOM, FUNI) and effective population size (NeLD), were used to quantify the impact of relatives mating on the genome of analysed populations. Even if the low NeLD estimates signalise significant loss of genetic variability within populations, the genomic inbreeding under 1% (except Jersey) showed that the intensity of diversity loss is not so rapid and can be managed by the re-arrangement of long-term breeding strategies. The analysis of genetic differentiation degree across populations assumed that the specialisation of breeds during their grading-up led to the specific nucleotide changes, especially in genes responsible for preferred phenotypic traits. The breed-specific differences observed mainly in the genome of Charolais (carcass traits) and Jersey (milk production traits) populations resulted from the polymorphisms in CAPN1 (μ-calpain) and CSN1S2 (casein alpha s2) genes, respectively. Obtained results confirmed that the specific haplotypes are strongly associated with the genetic nature of breed depending on production type.

scholarly journals Variation in brachiopod microstructure and isotope geochemistry under low-pH–ocean acidification conditions

2019 ◽  
Vol 16 (2) ◽  
pp. 617-642 ◽  
Author(s):  
Facheng Ye ◽  
Hana Jurikova ◽  
Lucia Angiolini ◽  
Uwe Brand ◽  
Gaia Crippa ◽  
...  
Keyword(s):  
Stable Isotope ◽  
Ocean Acidification ◽  
Isotope Geochemistry ◽  
Shell Growth ◽  
Low Ph ◽  
Secondary Layer ◽  
Ph Conditions ◽  
Set Up ◽  
The Impact ◽  
Δ13c And Δ18o

Abstract. In the last few decades and in the near future CO2-induced ocean acidification is potentially a big threat to marine calcite-shelled animals (e.g. brachiopods, bivalves, corals and gastropods). Despite the great number of studies focusing on the effects of acidification on shell growth, metabolism, shell dissolution and shell repair, the consequences for biomineral formation remain poorly understood. Only a few studies have addressed the impact of ocean acidification on shell microstructure and geochemistry. In this study, a detailed microstructure and stable isotope geochemistry investigation was performed on nine adult brachiopod specimens of Magellania venosa (Dixon, 1789). These were grown in the natural environment as well as in controlled culturing experiments under different pH conditions (ranging from 7.35 to 8.15±0.05) over different time intervals (214 to 335 days). Details of shell microstructural features, such as thickness of the primary layer, density and size of endopunctae and morphology of the basic structural unit of the secondary layer were analysed using scanning electron microscopy. Stable isotope compositions (δ13C and δ18O) were tested from the secondary shell layer along shell ontogenetic increments in both dorsal and ventral valves. Based on our comprehensive dataset, we observed that, under low-pH conditions, M. venosa produced a more organic-rich shell with higher density of and larger endopunctae, and smaller secondary layer fibres. Also, increasingly negative δ13C and δ18O values are recorded by the shell produced during culturing and are related to the CO2 source in the culture set-up. Both the microstructural changes and the stable isotope results are similar to observations on brachiopods from the fossil record and strongly support the value of brachiopods as robust archives of proxies for studying ocean acidification events in the geologic past.

Fructose-maltodextrin ratio in a carbohydrate-electrolyte solution differentially affects exogenous carbohydrate oxidation rate, gut comfort, and performance

2011 ◽  
Vol 300 (1) ◽  
pp. G181-G189 ◽  
Author(s):  
Wendy J. O'Brien ◽  
David S. Rowlands
Keyword(s):  
Oxidation Rate ◽  
Peak Power ◽  
Ingestion Rate ◽  
Carbohydrate Oxidation ◽  
Confidence Limits ◽  
Carbohydrate Ingestion ◽  
Oxidation Rates ◽  
Enhanced Absorption ◽  
And Performance ◽  
The Impact

Solutions containing multiple carbohydrates utilizing different intestinal transporters (glucose and fructose) show enhanced absorption, oxidation, and performance compared with single-carbohydrate solutions, but the impact of the ratio of these carbohydrates on outcomes is unknown. In a randomized double-blind crossover, 10 cyclists rode 150 min at 50% peak power, then performed an incremental test to exhaustion, while ingesting artificially sweetened water or one of three carbohydrate-salt solutions comprising fructose and maltodextrin in the respective following concentrations: 4.5 and 9% (0.5-Ratio), 6 and 7.5% (0.8-Ratio), and 7.5 and 6% (1.25-Ratio). The carbohydrates were ingested at 1.8 g/min and naturally 13C-enriched to permit evaluation of oxidation rate by mass spectrometry and indirect calorimetry. Mean exogenous carbohydrate oxidation rates were 1.04, 1.14, and 1.05 g/min (coefficient of variation 20%) in 0.5-, 0.8-, and 1.25-Ratios, respectively, representing likely small increases in 0.8-Ratio of 11% (90% confidence limits; ±4%) and 10% (±4%) relative to 0.5- and 1.25-Ratios, respectively. Comparisons of fat and total and endogenous carbohydrate oxidation rates between solutions were unclear. Relative to 0.5-Ratio, there were moderate improvements to peak power with 0.8- (3.6%; 99% confidence limits ± 3.5%) and 1.25-Ratio (3.0%; ±3.7%) but unclear with water (0.4%; ±4.4%). Increases in stomach fullness, abdominal cramping, and nausea were lowest with the 0.8- followed by the 1.25-Ratio solution. At high carbohydrate-ingestion rate, greater benefits to endurance performance may result from ingestion of 0.8- to 1.25-Ratio fructose-maltodextrin solutions. Small perceptible improvements in gut comfort favor the 0.8-Ratio and provide a clearer suggestion of mechanism than the relationship with exogenous carbohydrate oxidation.

Can feeding the broiler breeder improve chick quality and offspring performance?

2016 ◽  
Vol 56 (8) ◽  
pp. 1254 ◽  
Author(s):  
A. Chang ◽  
J. Halley ◽  
M. Silva
Keyword(s):  
Egg Production ◽  
Egg Size ◽  
High Energy ◽  
Direct Effects ◽  
Broiler Breeders ◽  
Offspring Performance ◽  
Shell Quality ◽  
Chick Quality ◽  
The Impact ◽  
Progeny Performance

The impact of nutrition on the performance of broiler breeders in terms of bodyweight profile, egg production, egg size and shell quality, mortality, fertility and hatchability has been well documented. However, studies on the direct effects of breeder nutrition on subsequent chick quality and offspring performance are limited. The present paper reviews the nutritional factors in broiler breeders that may improve chick quality and progeny performance. Recent research has suggested that the feeding of low crude protein and medium to high energy breeder diets in both rearing and laying period will not only have a positive impact on egg production, egg size, breeder fertility, hatchability and embryonic livability, but also on offspring performance. Improvements include better chick quality, higher chick weight, lower mortality, increased immune responses, enhanced litter quality and broiler growth. Breast-meat yield in the progeny can be improved as the energy to protein ratio increases from the rearing phase to the laying phase, indicating that nutrition of pullets can also affect growth and yields. The effects of maternal diet on offspring performance may depend on the sex of the progeny, with male broilers responding more than female broilers to breeders’ dietary protein and energy concentrations. However, little work has been conducted on the effects of individual amino acids in breeder diets on the subsequent generation. There seems to be some benefits with the use of long-chain poly-unsaturated fats in breeder diets on carcass quality of offspring, but these effects appear inconsistent at this stage. There is substantial evidence that confirms the direct effects of vitamin D and E, and trace minerals, especially in organic form, such as selenium, zinc and manganese, on chick quality and progeny performance. In fact, the impact of breeder nutrition on progeny performance in the field is more likely to be greater under conditions of poor breeder-flock uniformity, low vitamin and trace mineral contents or certain types of stress in the broiler house.

The Impact of Property Characteristics on Economic Performance of Russian Industrial Enterprises

2005 ◽  
pp. 53-68 ◽  
Author(s):  
R. Kapeliushnikov ◽  
N. Demina
Keyword(s):  
Detailed Analysis ◽  
Economic Performance ◽  
Ownership Concentration ◽  
Corporate Sector ◽  
Concentrated Ownership ◽  
Industrial Enterprises ◽  
Russian Industry ◽  
Control Premium ◽  
And Performance ◽  
The Impact

The paper provides new survey evidence on effects of concentrated ownership upon investment and performance in Russian industrial enterprises. Authors trace major changes in their ownership profile, assess pace of post-privatization redistribution of shareholdings and provide evidence on ownership concentration in the Russian industry. The major econometric findings are that the first largest shareholding is negatively associated with the firm’s investment and performance but surprisingly the second largest shareholding is positively associated with them. Moreover, these relationships do not depend on identity of majority shareholders. These results are consistent with the assumption that the entrenched controlling owners are engaged in extracting "control premium" but sizable shareholdings accumulated by other blockholders may put brakes on their expropriating behavior and thus be conductive for efficiency enhancing. The most interesting topic for further more detailed analysis is formation, stability and roles of coalitions of large blockholders in the corporate sector of post-socialist countries.

The Impact of Women’s Employment on Marital Stability in Qatar Society

2019 ◽  
Vol 10 (2) ◽  
pp. 144-151
Author(s):  
Noora Ahmed Lari ◽  
Keyword(s):  
Work Motivation ◽  
Marital Stability ◽  
Female Employment ◽  
Social Constraints ◽  
Primary Data ◽  
Family Policies ◽  
Insufficient Time ◽  
And Performance ◽  
The Impact ◽  
The Relationship

The State of Qatar has implemented several family policies in order to improve the wellbeing of Qatari families and ensure fair distribution of development benefits for both men and women. However, there is a linkage between female employment outside the home and instability in the marriages of Qatari families. This paper investigates the impact of female employment on marital stability, based on the results of primary data collected in Qatar, a questionnaire that consisted of several sections such as challenges in the workplace, supervisor, family and spouse relations, work motivation and performance. Of the 824 questionnaires that were returned, 807 were completed and valid for analysis. Regression analysis and an ANOVA test have been used to test the relationship between the variables. The results of the research have produced mixed findings about how wives’ employment increases marital instability and have yielded few significant differences on mean scores of discuss on work demands, insufficient time together, housework, financial matters, communication, relatives and rearing children. The results indicates that in general Qatar working women face several challenges in relation to their marital life as part of cultural and social constraints.

The Role of Research and Innovation in the Transformation of Agri-Food Systems

2018 ◽  
Vol 12 (2) ◽  
pp. 60-63
Author(s):  
Mariana Sandu ◽  
Stefan Mantea
Keyword(s):  
Technological Progress ◽  
Food Systems ◽  
Food System ◽  
Agricultural Research ◽  
Research And Innovation ◽  
And Performance ◽  
The Impact ◽  
Determinant Factor ◽  
Rapid Transformation

Abstract Agri-food systems include branching ramifications, which connect in the upstream the input suppliers with farmers, and downstream farmers, processors, retailers and consumers. In the last decades, at the level of the regions, food systems have undergone rapid transformation as a result of technological progress. The paper analyzes the changes made to the structure, behavior and performance of the agri-food system and the impact on farmers and consumers. Also, the role of agricultural research as a determinant factor of transformation of agri-food system is analyzed. The research objective is to develop technologies that cover the entire food chain (from farm to fork) and meet the specific requirements of consumers (from fork to farm) through scientific solutions in line with the principles of sustainable agriculture and ensuring the safety and food safety of the population.

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