Effects of alternative and natural prey on body size, locomotion and dispersal of Neoseiulus bicaudus (Acari: Phytoseiidae)

Prey are very important for the mass rearing of natural enemies and can affect the efficiency and quality of natural enemy products. Locomotion is important in dispersal of predatory mites on plants, and such activity is affected by body size and prey availability. The study evaluates the effects of prey (alternative prey: Tyrophagus putrescentiae Schrank and natural prey: Tetranychus turkestani Ugarov & Nikolskii) on the body size, locomotion and dispersal of the predatory mite Neoseiulus bicaudus Wainstein. When fed the alternative prey, the body size and locomotion of N. bicaudus were significantly lower than when fed the natural prey. However, the dispersal of N. bicaudus fed the two prey types was similar. The results suggest that long-term feeding on alternative prey could decrease the body size and locomotion of N. bicaudus. Nevertheless, the negative effects of alternative prey did not appear to affect the dispersal of N. bicaudus. The likely reason is that the type of prey does not affect the ability of the predatory mite to locate spider mites. In other words, when it fed alternative prey, N. bicaudus could still successfully disperse and locate spider mite-infested plants in the same way as when fed the natural prey.

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Re-adaptation from alternative prey to target prey increased predation of predator on target mite

Systematic and Applied Acarology ◽

10.11158/saa.24.3.10 ◽

2019 ◽

Vol 24 (3) ◽

pp. 467 ◽

Cited By ~ 2

Author(s):

Jie Su ◽

An-Di Zhu ◽

Guo-Dong Han ◽

Fang Dong ◽

Jing Chen ◽

...

Keyword(s):

Natural Enemy ◽

Spider Mite ◽

Biocontrol Agent ◽

Mass Rearing ◽

Predatory Mites ◽

Alternative Prey ◽

Tyrophagus Putrescentiae ◽

Potential Biocontrol Agent ◽

Tetranychus Turkestani

Neoseiulus bicaudus (Wainstein) is a natural enemy of spider mite and thrip and also a potential biocontrol agent for Tetranychus turkestani (Tetranychidae). Tyrophagus putrescentiae (Schrank) is an important alternative prey of N. bicaudus for mass rearing. We aimed to determine whether previous long-term feeding history, rearing on alternative prey versus target prey affected the performance of N. bicaudus. Therefore, the prey preference and functional response of predatory mites were compared between three strains: N. bicaudus fed on T. turkestani (TTS); N. bicaudus fed on T. putrescentiae (TPS); and N. bicaudus re-adapted from T. putrescentiae to T. turkestani (TPRS). When fed with the target prey, the preference rate and consumption of the TPS strain were significantly lower than the TTS strain. In addition, after 3-day-re-adaptation, the predatory mites (TPRS) increased their preference rate and consumption to target prey. The results suggested that re-adaptation before release could improve the ability of N. bicaudus to control its target prey.

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Long-Term Changes in the Diet of Gymnogobius isaza from Lake Biwa, Japan: Effects of Body Size and Environmental Prey Availability

PLoS ONE ◽

10.1371/journal.pone.0053167 ◽

2012 ◽

Vol 7 (12) ◽

pp. e53167 ◽

Cited By ~ 11

Author(s):

Jonathan Carlo Briones ◽

Cheng-Han Tsai ◽

Takefumi Nakazawa ◽

Yoichiro Sakai ◽

Rey Donne S. Papa ◽

...

Keyword(s):

Body Size ◽

Lake Biwa ◽

Prey Availability ◽

Long Term Changes

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Causes and Consequences of Broad-Scale Changes in the Distribution of Migratory Caribou (Rangifer tarandus) of Southern Hudson Bay

ARCTIC ◽

10.14430/arctic4524 ◽

2015 ◽

Vol 68 (4) ◽

pp. 472 ◽

Cited By ~ 3

Author(s):

Erica J. Newton ◽

Kenneth F. Abraham ◽

James A. Schaefer ◽

Bruce A. Pond ◽

Glen S. Brown ◽

...

Keyword(s):

Body Size ◽

Anthropogenic Disturbance ◽

Rangifer Tarandus ◽

The Body ◽

Dietary Quality ◽

Hudson Bay ◽

Substantial Change ◽

Term Data ◽

Broad Scale

Understanding the factors driving changes in species distributions is fundamental to conservation, but for wide-ranging species this is often complicated by the need for broad-scale observations across space and time. In the last three decades, the location of summer concentrations of migratory caribou (Rangifer tarandus) in southern Hudson Bay (SHB), Canada, has shifted south and east as much as 500 km. We used long-term data (1987 – 2011) to test two hypotheses that could explain the distribution shift: forage depletion and anthropogenic disturbance. Over time and space, we compared the body size of live-captured adult female caribou, dietary quality from fecal nitrogen in July, the location of VHF- and GPS-collared female caribou in July, distribution of all-terrain vehicle (ATV) tracks and caribou tracks in August, and the proximity of collared caribou to sections of the coast with higher ATV activity in spring and summer. The forage depletion hypothesis was supported by greater body size and dietary quality in caribou of the eastern portion of SHB than in western SHB animals in 2009 – 11. The anthropogenic disturbance hypothesis was supported by the negative correlation of the distributions of ATV tracks and caribou tracks on the coast in 2010 and the fact that caribou avoided areas with ATV activity by 10 – 14 km. In 1987, collared caribou were observed largely along the coast in western SHB in mid-July, while in 2009 – 11, they were inland in western SHB and along the coast in eastern SHB. While these locations demonstrate a substantial change in summer distribution over three decades, we were unable to differentiate between forage depletion and anthropogenic disturbance as a single causal factor of the distribution shift.

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Long Term Estimation for the Body Size and BMI of Korean Children & Youth Using ARIMA Model

Korean Journal of Sport Science ◽

10.24985/kjss.2016.27.3.530 ◽

2016 ◽

Vol 27 (3) ◽

pp. 530-542

Author(s):

채진석 ◽

Jongkook Song

Keyword(s):

Body Size ◽

Arima Model ◽

The Body ◽

Korean Children

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Entomopathogenic Rickia wasmannii fungal infection generated colony-level stress effects cause size decline in Myrmica ants

10.21203/rs.3.rs-289400/v1 ◽

2021 ◽

Author(s):

Sándor Csősz ◽

Zoltán Rádai ◽

András Tartally ◽

Lilla Erika Ballai ◽

Ferenc Báthori

Keyword(s):

Body Size ◽

Negative Effects ◽

Infection Level ◽

Stress Effects ◽

Myrmica Ants ◽

Body Sizes ◽

Myrmica Scabrinodis ◽

Rickia Wasmannii ◽

Colony Level

Abstract Parasitism-generated negative effects on ant societies are multifaceted, implying individual and colony-level responses. Though laboratory based evidence shows that the sublethal fungus Rickia wasmannii is responsible for physiological and behavioral responses that may negatively affect individual workers’ resilience and life expectancy in Myrmica ant workers, colony-level stress response to this parasite is largely unknown. Here, we focus on understanding of a long-term, colony-level effect of Rickia infection on Myrmica scabrinodis ant populations by tracking trait size-based changes. We collected worker specimens from infected and uninfected colonies from the same population in order to: (i) compare body size in response to parasitism, (ii) assess the extent to which possible changes in size are associated with the severity of infection, and (iii) investigate shifts in body size in response to infection over time by testing correlation of workers’ ages and sizes. We found that workers from infected colonies were significantly smaller than their healthy congeners, but neither infection level nor the age of the workers showed significant correlation with the size in infected colonies. Decreasing body sizes in infected colonies can be ascribed to workers’ mediated stress toward developing larvae, which are unable to attain the average body size before they pupate.

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Study on evolution of a predator–prey model in a polluted environment

Nonlinear Analysis Modelling and Control ◽

10.15388/namc.2021.26.24148 ◽

2021 ◽

Vol 26 (6) ◽

pp. 1052-1070

Author(s):

Bing Liu ◽

Xin Wang ◽

Le Song ◽

Jingna Liu

Keyword(s):

Body Size ◽

Function Analysis ◽

Fitness Function ◽

Rapid Evolution ◽

Evolutionary Model ◽

The Body ◽

Predator Prey ◽

Predator Prey Model ◽

Prey Model

In this paper, we investigate the effects of pollution on the body size of prey about a predator–prey evolutionary model with a continuous phenotypic trait in a pulsed pollution discharge environment. Firstly, an eco-evolutionary predator–prey model incorporating the rapid evolution is formulated to investigate the effects of rapid evolution on the population density and the body size of prey by applying the quantitative trait evolutionary theory. The results show that rapid evolution can increase the density of prey and avoid population extinction, and with the worsening of pollution, the evolutionary traits becomes smaller gradually. Next, by employing the adaptive dynamic theory, a long-term evolutionary model is formulated to evaluate the effects of long-term evolution on the population dynamics and the effects of pollution on the body size of prey. The invasion fitness function is given, which reflects whether the mutant can invade successfully or not. Considering the trade-off between the intrinsic growth rate and the evolutionary trait, the critical function analysis method is used to investigate the dynamics of such slow evolutionary system. The results of theoretical analysis and numerical simulations conclude that pollution affects the evolutionary traits and evolutionary dynamics. The worsening of the pollution leads to a smaller body size of prey due to natural selection, while the opposite is more likely to generate evolutionary branching.

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Effects of Storage Periods of an Artificial Larval Diet on the Yield and Quality of Mass-Reared West Indian Sweet Potato Weevil (Coleoptera: Curculionidae)

Journal of Economic Entomology ◽

10.1093/jee/toaa190 ◽

2020 ◽

Vol 113 (6) ◽

pp. 2613-2618

Author(s):

Kinjo Misa ◽

Chihiro Himuro ◽

Atsushi Honma ◽

Yusuke Ikegawa ◽

Tsuyoshi Ohishi

Keyword(s):

Body Size ◽

Adverse Effects ◽

Sweet Potato ◽

Artificial Diet ◽

Reproductive Potential ◽

West Indian ◽

Mass Rearing ◽

Artificial Diets ◽

Sweet Potato Weevil

Abstract Artificial diets have been employed for the mass-rearing of numerous insects because of their ease of use and standardized quality. An ability to store artificial diets under nonrefrigerated conditions over the long term could improve the efficacy of mass-rearing systems considerably. However, it remains largely unknown how long artificial diets can be stored at such temperatures without any adverse effects on the insects reared. In this study, we investigated yield, body size, and reproductive potential of West Indian sweet potato weevil, Euscepes postfasciatus (Fairmaire), which is a major sweet potato pest, under management using the sterile-insect technique in Japan and reared using artificial diets with different storage periods (14, 28, and 42 d) at nonrefrigerated temperatures (25 ± 1°C), and compared them with those of the control (0 d). Notably, E. postfasciatus yield and reproductive potential increased significantly with an increase in storage period (28 and 42 d). Conversely, male body size decreased significantly following feeding with artificial diet stored for 42 d, when compared with the control, while there were no significant differences in female body size between the control and all the treatments. We discuss the potential causes of such varying effects between yield and body size and conclude that E. postfasciatus artificial diet can be stored for at least 28 d without any adverse effects on weevil yield and weevil quality. To the best of our knowledge, this is the first report revealing the positive effects of long-term storage of the artificial diet on mass-reared insects.

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Effects of preweaning nutritional deprivation on basal metabolism and thermoregulatory thermogenesis in the rat

British Journal Of Nutrition ◽

10.1079/bjn19860142 ◽

1986 ◽

Vol 56 (3) ◽

pp. 615-623 ◽

Cited By ~ 4

Author(s):

D. V. Muralidhara ◽

P. S. Shetty

Keyword(s):

Body Size ◽

The Body ◽

Metabolic Efficiency ◽

Nutritional Rehabilitation ◽

Adequate Diet ◽

Nutritional Deprivation ◽

Short Period ◽

Body Weights ◽

Before And After

1. Nutritional deprivation was induced preweaning in Wistar rats by increasing the litter size to sixteen, while paired litters with only five pups served as controls. The nutritionally deprived pups were rehabilitated after weaning by ad lib. access to an adequate diet.2. The body-weights and body lengths were significantly lower in the nutritionally deprived group and significant differences persisted even after 9 weeks of rehabilitation.3. The body temperature of the nutritionally deprived animals was significantly lower than that of their paired controls, both before and following nutritional rehabilitation, except for a short period after weaning when the nutritionally deprived animals were initially given the diet ad lib.4. The resting oxygen consumption of the nutritionally deprived animals was comparable to that of the controls when corrected for metabolic body size, both before and after weaning. Noradrenaline-stimulated increase in 02 consumption (non-shivering thermogenesis; NST) was reduced by 50% at weaning in the nutritionally deprived animals and returned to levels comparable to those of controls within a short period of rehabilitation.5. The decrease in NST capacity seen in the nutritionally deprived animals was associated with an inability to thermoregulate when exposed to cold (5°), resulting in death. Cold-induced thermogenesis (CIT) also reappeared soon after nutritional rehabilitation.6. Reduction in metabolic rate, NST and CIT seen in the animals nutritionally deprived preweaning was short-lived and disappeared soon after nutritional rehabilitation. Rapid reversal of these physiological changes indicates that they do not confer any long-term benefit or change in metabolic efficiency and are unlike the changes in body size and growth which do not completely recover following nutritional rehabilitation.

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Demanding Activation

Journal of Social Policy ◽

10.1017/s004727941600057x ◽

2016 ◽

Vol 46 (2) ◽

pp. 349-365 ◽

Cited By ~ 26

Author(s):

TANIA RAFFASS

Keyword(s):

Labour Market ◽

Social Impact ◽

Full Employment ◽

The Body ◽

Welfare To Work ◽

Negative Effects ◽

Distinctive Character ◽

The Business Cycle ◽

Political Economic

AbstractThe distinctive character of the unemployment policies overhaul, known as the ‘activation turn’ of the 1990s, was that OECD governments intensified coercion against unemployed individuals while relaxing their commitment to ensuring full employment. By now supply-side activation policies have been tested long enough to permit conclusive evaluations, and the article surveys the body of empirical assessments to determine the achievements of the activation turn. The implementation of welfare-to-work policies has not resulted in bringing down the rates of unemployment (independently of the business cycle), combating long-term unemployment, reducing (in-work) poverty or empowering jobseekers as consumers of public services, which were all goals of the reformed ‘activating state’. Instead, activation has been working as a mechanism of entrapment at the margins of liberalised labour markets by dint of its complementarity with employer-centred flexibility. The activation turn has thus failed to achieve its direct labour market and social objectives. However, it has produced pronounced indirect negative effects in the labour market, and its social impact has been regressive and repressive, as anticipated in normative and political-economic critiques of the rising ‘workfare state’.

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