Food Limitation Research Articles

Biomass Quality Variations over Different Harvesting Regimes and Dynamics of Heavy Metal Change in Miscanthus lutarioriparius around Dongting Lake

Miscanthus lutarioriparius has a growing area of 100,000 ha and an annual biomass production of 1 Mt around Dongting Lake. However, due to serious soil pollution, there is a concern that the M. lutarioriparius biomass could have high heavy metal (HM) concentrations. This necessitates investigation of biomass quality to find the appropriate end use. Thus, this study aims to investigate the dynamics of HM elements in the M. lutarioriparius biomass and their impact on biomass quality across different growing areas and harvest times. We analyzed the HM concentrations in soil and biomass from 11 sites under different harvesting times (April, August and December). Results showed that Cd in soil samples was 9.43-fold higher than the national standards. The heavily polluted soil caused a high HM concentration in the biomass and the accumulation increased with the delayed harvest. The fresh young shoots in April met the food limitation for Cd and Cr, whereas Pb concentration was slightly higher than the threshold limit. The mature biomass from the southern part had higher Mn, Cd and Pb, but lower Cu, Zn and Cr concentrations than that from the eastern part. These results can provide guidance for guaranteeing the consistent quality of the M. lutarioriparius biomass for bio-based industry.

Distribution pattern of Pb and Zn contamination in rivers near industrial zone in Aceh, Indonesia, revealed by principal component analysis (PCA)

The research aims to evaluate the pollution of Pb and Zn in water, sediment, and Faunus ater samples collected from Krueng Balee (KB) and Kreung Reuleung (KR) Rivers, Aceh, Indonesia. The samples were collected at the upstream, midstream, and downstream of each river and analyzed using Atomic Absorption Spectrophotometry (AAS). The distribution of Pb and Zn pollution was analyzed using Principal Component Analysis (PCA). Our investigation revealed that the presence of Pb and Zn is still safe for water and sediment samples. Nevertheless, Pb and Zn contamination found in F. ater samples had exceeded the national safety limit for food. PCA analysis revealed correlations between samples suggesting the roles of physical and chemical properties of the river in the pollutant retainment. The analysis also indicated the possible antagonism between Pb and Zn accumulation in F. ater which has never been reported previously. We suggest routine monitoring of Pb and Zn concentrations. The role of the surrounding industry in the Pb and Zn pollution should be further studied.

Herbivore population dynamics in response to plant allocation strategies

When herbivores feed, plants may respond by altering the quantity of edible biomass available to future feeders through mechanisms such as compensatory regrowth of edible structures or allocation of biomass to inedible reserves. Previous work showed that some forms of compensatory regrowth can drive insect outbreaks, but this work assumed regrowth occurred without any energetic cost to the plant. While this is a useful simplifying assumption for gaining preliminary insights, plants face an inherent trade-off between allocating energy to regrowth versus storage. Therefore, we cannot truly understand the role of compensatory regrowth in driving insect outbreaks without continuing on to more realistic scenarios. In this paper, we model the interaction between insect herbivores and plants that have a trade-off between compensatory regrowth and allocation to inedible reserves in response to herbivory. We found that the plant’s allocation strategy, described in our model by parameters representing the strength of the overcompensatory response and the rates at which energy is stored and mobilized for growth, strongly affects whether herbivore outbreaks occur. Additional factors, such as the strength of food limitation and herbivore interference while feeding, influence the frequency of the outbreaks. Overall, we found a possible new role of overcompensation to promote herbivore fluctuations when it co-occurs with allocation to inedible reserves. We highlight the importance of considering trade-offs between tolerance mechanisms that plants use in response to herbivory by showing that new dynamics arise when different plant allocation strategies occur simultaneously.

Accumulation of metallic trace elements in Reynoutria japonica: a risk assessment for plant biomass valorization

Sustainable solutions aiming at limiting Reynoutria japonica invasion consist of frequent removal of its aerial biomass. The aims of this study were to measure the accumulation of metallic trace elements (MTE) in R. japonica, and to assess the eco-toxicological risk related to the valorization of the produced biomass. R. japonica fragmented rhizomes were regenerated in pots for 41 days on a control soil (CTL) or a moderately MTE-contaminated soil (POL, 3.6 mg Cd kg−1 DM). Growth traits were recorded, as well as MTE bioconcentration (BCF) and translocation factors (TF) from soil to plant organs. Whatever the MTE and plant organs, BCF remained below one (mean Cd-BCF for stem and leaf: 0.07 and 0.29 for CTL and POL, respectively), conversely to TF (until 2.2 for Cd and Ni in POL soil). When grown on the POL soil, R. japonica stem and leaf Cd content was close to the EU maximum regulatory limit for organic amendments or animal feed. Model simulations suggested that liver and kidney Cd concentrations would exceed the regulatory limit in food when adult cattle or sheep constantly ingest R. japonica grown on the POL soil over 200 to 800 days. The results of the present study will be useful to help managers in selecting efficient and safe solutions for the control of R. japonica invasion.

Effect of a High Protein, Low Glycemic Index Dietary Intervention on Metabolic Dysfunction-Associated Fatty Liver Disease: A Randomized Controlled Trial.

Background:Metabolic dysfunction-associated fatty liver disease (MAFLD) affects people at an increasingly younger age. The primary treatment for patients with MAFLD is diet-induced weight loss; however, excessive dieting is poorly effective.ObjectivesThe aim of this trial was to evaluate whether a high protein and low glycemic index (HPLG) dietary intervention would result in improvement of controlled attenuation parameter (CAP) and related metabolic markers in MAFLD.MethodsA 12-week controlled, parallel-group, randomized intervention trial was performed. A number of 63 participants with MAFLD were enrolled and randomized between the HPLG dietary group and the balanced diet control group. Both diets had the same hypocaloric level and were prescribed ad libitum within food limit lists. The primary outcome was CAP. The main secondary outcomes were weight loss and improvement of metabolism-related indexes at week 12 after the program initiation.ResultsA total of 59 participants completed the intervention and were included in the final analysis. The mean age was 39.3 ± 8.9 years and 66.1% were men. In this trial, protein and carbohydrate intakes were significantly higher and lower, respectively, in the HPLG group compared to controls (p < 0.001). At week 12, CAP was significantly reduced in both groups (p < 0.001). However, a significantly greater reduction in liver fat was observed in the HPLG group compared to the control group (p = 0.011), with mean relative reductions of 30.90 dB/m (95% CI, 21.53 to 40.26, p < 0.001) and 15.43 dB/m (95% CI, 7.57 to 23.30, p < 0.001), respectively. From baseline to week 12, a significantly greater loss in bodyweight was recorded in participants in the HPLG group (6.52 kg; 95% CI, 5.50 to 7.54, p < 0.001) compared to control subjects (2.00 kg; 95% CI, 0.89 to 3.11, p = 0.001). Moreover, body fat percentage in the HPLG group was significantly reduced compared with the control group (p = 0.002). Within-group improvements in visceral fat, blood pressure, cardiovascular risk factors, and blood glucose-related indicators were detected in patients with MAFLD assigned to the HPLG diet (p < 0.05), but not in those prescribed the control diet (p > 0.05).ConclusionUnder our experimental conditions, and compared to the traditional balanced diet, an HPLG diet led to a significant CAP remission, bodyweight or fat reduction, and improvement of metabolic markers in patients with MAFLD.Clinical Trial RegistrationClinicalTrials.gov, identifier: NCT03972631.

Response of alewife abundance to the bacterial kidney disease outbreak in the Chinook salmon population of Lake Michigan: importance of predation

Prey fish abundance can be influenced by predation (top-down) and food limitation (bottom-up) effects. I characterized temporal trends in yearling and older (YAO) alewife (Alosa pseudoharengus) biomass density, as estimated by a long-term bottom trawl survey, in Lake Michigan during 1973–2019. Special attention was given to the bacterial kidney disease (BKD) outbreak in the population of Chinook salmon (Oncorhynchus tshawytscha), the predominant predator on alewives in the lake. YAO alewife biomass density exhibited a steep and significant decline during 1973–1985, but then partially rebounded with a significant increase between the 1983–1985 and 1986–2003 (BKD years) periods, followed by a significant decrease between the 1986–2003 and 2004–2006 periods. YAO alewife biomass density showed another significant decline during 2004–2019. The BKD outbreak led to a partial relaxation of predation on the YAO alewife population, and YAO alewife biomass density responded by showing a moderate increase in 1986 and then fluctuating about this moderately higher level for more than 15 years. Overall, temporal trends in YAO alewife biomass density were primarily driven by predation.

Bridging environment, physiology and life history: stress hormones in the Edible Dormouse (Glis glis)

The performance of wild animals is impacted by diverse challenges imposed by the environment and distinct life history stages such as breeding and hibernation. Glucocorticoids (GCs) are hormonal mediators that reflect the response to these challenges, exerting their far-reaching effects on numerous processes such as energy allocation, immunity and behavior. Whereas short term elevations of GC levels are crucial for survival, by activation of the emergency life history stage, chronically increased GCs are capable of impairing various body functions and ultimately hamper survival and reproduction. The aim of this study was to disentangle the effects of reproductive activity, prolonged food limitation and hibernation on stress hormone levels in the Edible Dormouse (Glis glis) and to link them to formerly observed survival rates. We therefore measured urinary cortisol levels in wild Edible Dormice in South-western Germany during their active season (2012-2014). Results of our study revealed that reproductive activity was associated with high cortisol levels. During the mating season, particular individuals with a low body mass had high stress hormone levels. Elevated levels of cortisol were also measured during pre-hibernation fattening and were increased in females that had formerly invested in reproduction. Thus, reproduction represents a demanding, potentially stressful, event for both sexes and is linked to distinctly lowered survival rates occurring during years of high reproductive activity. Prolonged food limitation occurring during years of mast failure, did not affect stress levels and were not associated with increased mortality, demonstrating the ability of dormice to predict and cope with food restriction.

Increasing temperature and prey availability affect the growth and swimming kinematics of Atlantic herring (Clupea harengus) larvae.

Climate change will increase the magnitude and duration of warming events and the variability in the phenology and abundance of available prey to the early life stages of fish. These factors influence physiological, behavioral and ecological processes, impacting growth, development and survival. Using a fully factorial design with two prey-availability treatments (1200 prey items L−1 (high prey abundance) or 40 prey items L−1 (low prey abundance)) under three temperature regimes (8, 10 and 12°C), the swimming kinematics of 6-week old spring-spawning Atlantic herring larvae were examined using silhouette video photography. Higher temperatures combined with food limitation significantly decreased the growth and swimming kinematics of larval herring, with the most negative effect observed in larvae reared at 12°C and exposed to low food abundances. Specifically, larvae displayed reduced locomotory behaviors and reduced vertical movements. By contrast, larvae reared at high prey abundance and at 12°C displayed more active swimming and exploratory behavior, as evidenced by an increase in both locomotory behavior and vertical and horizontal turn angles, suggesting increased motivation to search for food. This research highlights the importance of determining to what degree fish larvae are sensitive to changes in temperature and how these changes might be further influenced by food availability.

Evaluation of poly(L-lactic acid) (PLLA) rapid indicator film on deterioration degree of Refined, Bleached and Deodorised Malaysian Tenera palm olein oil (RBDPO) during long-term repetitive deep-fat frying

Palm olein oil is widely used as a medium for deep-frying purposes in the domestic and commercial sectors. However, repetitive usage beyond the recommended cycle leads to significant deterioration and spoilage of the oil. Therefore, this research investigated the effect of long-term repetitive deep-fat frying on the physicochemical properties of Refined, Bleached and Deodorised Malaysian Tenera Palm Olein oil (RBDPO) as well as the suitability of poly(L-lactic acid) (PLLA) film as a potential rapid indicator to determine the spoilage level of recycled palm olein oil. The study was carried out using three different RBDPO conditions; RBDPO without potatoes (RBDPO-1), RBDPO with potatoes (RBDPO-2), and RBDPO with Afdhal Oil (AO, an oil additive chemical) and potatoes (RBDPO-3). The deep-frying process was performed for 15 mins at 180 ± 5 °C for 15 cycles. Based on the results, the oil temperature fluctuation during the frying process was insignificant for every cycle ( p > 0.05). After 15 frying cycles, all oil samples demonstrated a considerably altered and deteriorated composition, both physically and chemically. The comparison between the 1st and 15th frying cycles showed a significant difference ( p < 0.05) in the decrease of moisture content and contact angle. Furthermore, the redness colour and viscosity for RBDPO-1, RBDPO-2 and RBDPO-3 increased significantly. The RBDPO-2 recorded the highest value for moisture content, contact angle, colour and viscosity after 15 frying cycles with 30.40 ± 0.2%, 26.01 ± 0.02°, 10.77 ± 0.15 Lovibond, and 133.5 ± 0.2 cP, respectively. However, the density value was insignificant ( p > 0.05) between the 1st and 15th frying cycles for all types of oil. Besides, the peroxides value (PV) was steadily increased within the safety limit of Food Act (1983) (Laws of Malaysia: Act 281), with the aldehyde (C O) functional group was detected in all oil samples throughout the 15 frying cycles. Hence, the high correlation between the contact angle and all parameters except density showed that contact angle analysis using PLLA film was a suitable technique for rapid oil spoilage indicator model.

Crowding does not affect monarch butterflies' resistance to a protozoan parasite.

Host density is an important factor when it comes to parasite transmission and host resistance. Increased host density can increase contact rate between individuals and thus parasite transmission. Host density can also cause physiological changes in the host, which can affect host resistance. Yet, the direction in which host density affects host resistance remains unresolved. It is also unclear whether food limitation plays a role in this effect. We investigated the effect of larval density in monarch butterflies, Danaus plexippus, on the resistance to their natural protozoan parasite Ophryocystis elektroscirrha under both unlimited and limited food conditions. We exposed monarchs to various density treatments as larvae to mimic high densities observed in sedentary populations. Data on infection and parasite spore load were collected as well as development time, survival, wing size, and melanization. Disease susceptibility under either food condition or across density treatments was similar. However, we found high larval density impacted development time, adult survival, and wing morphology when food was limited. This study aids our understanding of the dynamics of environmental parasite transmission in monarch populations, which can help explain the increased prevalence of parasites in sedentary monarch populations compared to migratory populations.

Factors Influencing Stress Perception among Hemodialysis Patients: A Systematic Review

Background: Stress is a common comorbid disorders among hemodialysis patients and diverse factors contributed for stress perception among hemodialysis patients. Although, many findings have been consistent across the literature, there has been a surprising lack of consensus in which factor is most influence the stress perception. Objectives: This systematic review aimed to provide executive review on factors contribute for stress perception among hemodialysis patients Methods: Systematic review was conducted in Cumulative Index to Nursing and Allied Health Literature (CINHAL), PubMed, EBESCOhost, Google scholar, Medline and Web of Science (WOS) databases. Rigorous search narrowed to 16 observational studies (Total N=3567) on factors determine for stress perception among hemodialysis patients. Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guideline were inco-operated. Selected 16 articles were used in the qualitative synthesis. Results: Stressors were clustered as Biological, Psychological/Behavioral, or Social/Environmental factors. Effect of socio-demographic factors on stress perception was scarce and inconsistent; whilst fatigue and itching were distressing biological factors. Limitations on time and place on vacation, limitation of food and fluid, decrease in social life with substantial economic burden were enlightened as psychological and social stressors respectively. Conclusion: Multidisciplinary factors were inspired for stress perception among hemodialysis patients. Nursing care plans should addressed holistic nature of stress with appropriate nursing interventions. Although this review adopted the strict selection criteria, it remains difficult to conclude determinants due to methodological drawbacks. Thus, future research in this scope is highly appreciated with prospective longitudinal nature to produce solid clinical conclusions.

Ecological and Health Risk Assessments Based on the Total Amount and Speciation of Heavy Metals in Soils Around Mining Areas

Topsoil and supporting crop samples around a mining area were collected in Longyan City, and the total amounts and speciation of Pb, Cd, and As in the samples were determined. The ecological risk and human health risk assessment of soil heavy metals Pb, Cd, and As were carried out using the Hakanson potential ecological risk assessment method, the ecological risk classification method based on the principle of geochemical statistics, and the health risk assessment method in accordance with the characteristics of human exposure parameters in China. The results indicated that the heavy metal elements in the soil in the study area exceeded the environmental quality standards for Pb and Cd, and the heavy metal contents in cereal grains exceeded the food limit value mainly for Pb. The proportion of the four bioavailable forms except the residue state followed the order of Pb>Cd>As. The ecological risk assessment results based on the total amount of heavy metals and bioavailable forms showed that Cd was the most important ecological risk factor. The single potential ecological risk of Cd and the comprehensive ecological risk of Pb, Cd, and As in the soil based on bioavailable forms were significantly reduced compared with that based on the total amount. The proportion of medium and superior samples decreased from 100% and 50.0% to 17.2% and 7.81%, respectively, and the divided risk zone basically contained all the warning points of exceeding the standard of crops. Oral ingestion was the main carcinogenic and non-carcinogenic exposure route of heavy metals. In terms of carcinogenic risk, the risk of human carcinogenic health exposure to Cd and As was within the acceptable range, regardless of whether bioavailability was considered. Among the non-carcinogenic risks, the non-carcinogenic risk of the heavy metal Cd was negligible. When only the total amount of heavy metals was considered, the non-carcinogenic risk index of Pb and As under the three exposure pathways ranged from 0.14 to 8.65 and from 0.04 to 2.85, respectively. After considering the adjustment of bioavailability, the non-carcinogenic risk of As was greatly reduced and could be considered to no longer have non-carcinogenic risk. Although the non-carcinogenic exposure risk index of Pb was reduced by 84.7%, the maximum value still reached 1.69, which would cause non-carcinogenic harm to the population and was the key to soil remediation in mining areas.

Effects of spatial scale on assessments of suspension bivalve aquaculture for productivity and environmental impacts

Proper evaluations of productivity and environmental impacts of bivalve aquaculture are necessary to achieve sustainable operations in coastal marine systems. Estimation of organic matter budgets using completely mixed one-box models provides an easy approach to help stakeholders of environmental management and aquaculture fisheries obtain an overview of the interactions between aquaculture and the environment. However, estimations and interpretations are highly dependent on the spatial scale of assessments because the distributions of aquaculture facilities and ecosystem structures are spatially heterogeneous. The objective of the present study was to examine how the spatial scale of assessments for the budgets of particulate organic matter (POM) affects the interpretation of the site-specific food supply for suspension oyster aquaculture and impacts of oyster biodeposition on local bottom environments. Based on the actual distribution of oyster farms in a temperate bay on the northeast coast of Japan, we estimated [food supply]/[food demand] (S/D) for oysters as well as the relative contribution of oyster biodeposition to the total deposition of POM (Brel) in the bay along a gradient of spatial scales l from 0.5 m to 4000 m. Although food limitation for aquaculture oysters has been reported in the study bay, S/D was greater than 1 (ranging from 16 to 154) over the spatial scale gradient. S/D tended to be relatively high and overestimated for l < 200 m and l > 1400 m due to the nature of completely mixed one-box models, but relatively lower at intermediate scales. Brel was higher in assessments at farms or smaller scales (e.g., l < 100 m) and was relatively lower at larger scales (e.g., <0.2 at the scale of >500 m). Based on our model-based calculations, the patterns of variation in S/D along the spatial scale gradient are considered to be universal; however, the scale at which S/D values are relatively low varies depending on site-specific conditions, including primary productivity and current velocity. Our findings suggest that estimated budgets of POM need to be carefully interpreted, accounting for model assumptions as well as the influence of the spatial scale of assessments.

Detecting food limitation of bacterial growth during dilution experiments

The dilution method is typically applied to estimate the growth and mortality rates of phytoplankton, but it is also used to study bacterioplankton. The method comprises creating a gradient of dilutions to reduce the encounter rates between bacterivores and bacteria, thus allowing for estimations of bacterial growth and grazing pressure exerted on the bacteria. However, the manipulations involved in the method can lead to biased results. In this study, 12 dilution experiments performed in the coastal zone of the Baltic Sea were accompanied by additional measurements capable of detecting possible artefacts. Only six measurements performed during spring and summer (March–August) produced results that were free of artefacts and were statistically significant. During fall and winter (October–February) measurements were unsuccessful because of food limitation of bacterial growth during experimental incubation. Twice (in September and October) bacterial growth and grazing mortality rates were underestimated because grazing pressure was not successfully removed. The study demonstrated that 24-hour and five-day oxygen consumption measurements incorporated into dilution experiments permitted estimating the fraction of biodegradable organic matter used during incubation, and, thus, detecting the food limitation of bacterial growth.

Modelling the effects of food limitation and temperature on the growth and reproduction of the krill Nyctiphanes australis

The krill Nyctiphanes australis is the most abundant and ecologically important euphausiid in southern Australia and New Zealand coastal and shelf waters. The species lives in coastal environments which are currently susceptible to shifts in temperature and productivity. Due to its abundance, it sustains many inshore fisheries and, for this reason, determining the potential outcome of future changes in sea temperature and productivity for Nyctiphanes is important. The temperature- and food-dependence of growth and reproduction of Nyctiphanes species can be made through Dynamic Energy Budget models (DEB), developed here to quantify how temperature and food availability affects growth, fecundity, egg size, and the energetic content of the eggs throughout the krill life-span. The DEB model predictions are in good agreement with measured life-history traits for the species and show that krill grows slower during winter while females do not always reach sexual maturity when temperatures are below 8 °C and food levels are low. We found that higher temperatures and low food levels decrease the energetic content and diameter of the eggs by ∼20%, affecting the length and age at which N. australis commence reproduction. Under current scenarios of future ocean warming, these results indicate that populations of N. australis are likely to decline, with potential knock-on effects on coastal marine ecosystems and inshore fisheries.

Chemical composition, sensory and microbial attributes of porridges prepared from African yam bean (Sphenostylis stenocarpa) and corn (Zea mays) flour blends

Background: The dietary challenges facing type 2 diabetics have necessitated the development of high fiber indigenous diets for the management/control of blood glucose.&#x0D; Objectives: The study determined the chemical composition, sensory and microbial attributes of porridges prepared from African yam bean (AYB) and corn flour blends.&#x0D; Methods: AYB seeds roasted at 1910C for 40 min and corn oven-dried at 500C for 24 h were finely milled, evaluated for proximate composition and dietary fiber profile and formulated into 5 flour samples in the ratios of 100, 70:30, 50:50, 30:70, 100 to supply one-third (1/3) of the daily dietary fiber requirement (12.7 g) of a reference man (70 kg). The 5 samples (including 3 composites) together with the control (traditional corn flour) provided 6 samples for the study. The samples were made into porridges and evaluated for chemical composition, sensory and microbial attributes using standard procedures. Data generated were analyzed using the IBM Statistical Product for Service Solution statistics version 21. Results were presented as means and standard deviations, Analysis of variance (ANOVA) was used to compare the means and significance was accepted at p &lt; 0.05.&#x0D; Results: The proximate, minerals, vitamins and phytochemical compositions of the porridges were superior to the traditional corn porridge (control). No anti-nutrients were detected in all the porridges. Flavonoids (0.01 to 0.04 mg) and saponins (0.01 to 0.05 mg) were present in the porridges but not in the control. Viable organisms (Staphylococcus aureus, Bacillus cereus, Micrococcus spp, Enterobacter aerogenes, Pencillum spp. Rhizopus spp.) that were unnatural microfloral of AYB and corn seeds were detected in the porridges. The microbial loads (1.2 x 101 to 2.0 x 102 cfu/g) were within the acceptable International Commission on Microbiological Specification of food limits of 105 cfu/g. More coliforms and fungal growth were observed in porridges with higher proportions of corn. All porridges rated higher (5.08 - 6.67) on the acceptability scale than the traditional corn porridge (4.00).&#x0D; Conclusion: The high-fiber AYB-corn porridges had improved nutrient content, safe microbial load and consumer acceptability than the traditional corn porridge, and will add variety to diabetic meals.

Two Decades of Match-Mismatch in Northeast Arctic Cod – Feeding Conditions and Survival

The successful recruitment of Northeast Arctic (NEA) cod is thought to depend on sufficient and suitable prey for the newly hatched larvae, in particular the nauplii stages of the lipid-rich calanoid copepod species Calanus finmarchicus. The role of spatial and temporal variations in prey availability in combination with temperature and other factors in influencing growth and survival of cod larvae is, however, incompletely understood. By combining an individual based model for NEA cod larvae at the Norwegian coast with a high-resolution ocean model and a nutrient-phytoplankton-zooplankton-detritus model providing 18 years of daily environmental conditions and prey availability we assessed larval growth and survival until they settle in their feeding habitat in the Barents Sea in early fall. We find on average a two-week delay from the peak timing of first-feeding cod larvae to the peak in prey availability. In warm years, more larvae experience food limitation than in normal years. The positive effects of high temperature on growth, survival and ultimately recruitment are nonetheless larger than the negative effects of food limitation. Food limitation mainly affects larvae spawned in southern areas or late in the spawning season as these larvae experience the highest temperatures and have the highest energy requirements. Our findings highlight the spatial and temporal differences in mechanisms that regulate growth and survival of early life stages of NEA cod and suggest that spatially resolved data may be essential for understanding match-mismatch dynamics.

Medical and Veterinary Ectoparasites' Importance: An Insight on Alternative Control

Numerous ectoparasites of people and domestic cattle remain a chronic concern in the contemporary world, despite many attempts at eradication. For many years, pesticide medications such as organophosphates, organochlorides, and synthetic pyrethroids were efficient in controlling these parasites; however, widespread use of these treatments has resulted in resistance in many target species. Domestic animals play a vital role in food production, producing meat, milk, and money. The agricultural communities raze livestock’s as an insurance and investment in contradiction of risk. Animals with short generation intervals and high fertility offer economic, managerial, and biological benefits, since milk production can start five or six months after mating and the first corpse can be sold in less than a year. Livestocks are also a main source of manure, which helps to fertilize the soil, as well as skin, which is one of the most significant products that generates foreign cash for the country. However, the combined effects of sickness, inadequate food, and bad management limit animal output. Parasitic sickness is one of the most common disorders in domestic animals and human, and it has a significant economic impact. Ectoparasites of livestocks are extensively dispersed with varying degrees of incidence, and are crucial in causing considerable economic damage to the agricultural community, the tanning and leather sector even throughout the wolrd, necessitating efficient control methods. Scabies mites, head lice, and bed bugs are important medical ectoparasites that pose a considerable public health threat, hence effective management strategies are required. Alternative management approaches have been developed in a number of ways, but more study is needed before they can be utilized to effectively regulate the ectoparasitic illnesses in the forthcoming. Keywords: Human; Livestocks; Parasites; Biological control; Chemical control

Heavy metal pollution and net greenhouse gas emissions in a rice-wheat rotation system as influenced by partial organic substitution

Substituting nitrogen fertilizer with organic manure is a common fertilization practice in farmland, but its potential effect on heavy metal pollution and greenhouse gas (GHG) emissions remains unclear. A three-year field experiment was conducted in the rice-wheat rotation system, with two different substitution ratios (25% and 50%) of sewage sludge compost (SS) and pig manure compost (PM). With the substitutions of SS and PM, the heavy metals, including Cu, Zn, Cd, and Pb were accumulated in the soil, but the pollution load index was <1 (0.39–0.66), indicating that soil was not polluted. Heavy metals Ni and Cu were mainly found in rice chaff, while Zn and Cd were accumulated in rice stalk, and the accumulation of Pb occurred in the leaf. For wheat, Ni, Cu, and Pb were accumulated in chaff, while grain and stalk had the highest concentrations of Zn and Cd, respectively. Moreover, the bioconcentration factor of heavy metals was 0–0.787, and their contents were below the standard limits for foods for rice and wheat in China, implying that the grains were unpolluted. Given the 5–8 fold increase in the sequestration rate of soil organic carbon with SS and PM substitutions, the annual net GHG emissions were reduced by 115–166%. Most importantly, 50% SS substitution exhibited the lowest net GHG emissions and highest rice and wheat yields. Overall, the results suggested that 50% SS substitution would be a feasible fertilization strategy that not only is unlikely to pose a high risk of soil and grain pollution but also significantly mitigates net GHG emissions and maintains high yields.

Evaluating the effects of water and food limitation on the life history of an insect using a multiple-stressor framework.

Many environmental stressors naturally covary, and the frequency and duration of stressors such as heat waves and droughts are increasing globally with climate change. Multiple stressors may have additive or non-additive effects on fitness-related traits, such as locomotion, reproduction, and somatic growth. Despite its importance to terrestrial animals, water availability is rarely incorporated into multiple-stressor frameworks. Water limitation often occurs concurrently with food limitation (e.g., droughts can trigger famines), and the acquisition of water and food can be linked because water is necessaryfor digestion and metabolism. Thus, we investigated the independent and interactive effects of water and food limitation on life-history traits using female crickets (Gryllus firmus), which exhibit a wing dimorphism mediating a life-history trade-off between flight and fecundity. Our results indicate that traits vary in their sensitivities to environmental factors and factor-factor interactions. For example, neither environmental factor affected flight musculature, only water limitation affected survival, and food and water availability non-additively (i.e., interactively) influenced body and ovary mass. Water availability had a larger effect on traits than food availability, affected more traits than food availability, and mediated the effects of food availability. Further, life-history strategy influenced the costs of multiple stressors because females investing in flight capacity exhibited greater reductions in body and ovary mass during stress relative to females lacking flight capacity. Therefore, water is important in the multiple-stressor framework, and understanding the dynamics of covarying environmental factors and life history may be critical in the context of climate change characterized by concurrent environmental stressors.